Published March 1, 2024
With this blog post, we are continuing our series on preventing and reversing insulin resistance. As I have discussed in this blog post, there are numerous factors that can cause insulin resistance. The most important factor in most people is excess body fat mass, and specifically excess visceral and ectopic fat. Therefore, understanding the keys to a healthy body weight will be critical to helping us maintain a healthy body fat mass, or lose excess visceral and ectopic fat without immediately regaining it. So let’s start by discussing …
How to Think about Satiety, Calorie Counting, Dieting, and Weight Loss
The figure below shows a woman named Anne. Let’s assume it’s lunchtime. Anne is hungry and sits down to eat. She eats until she is comfortably full. Now, what is it about her meal that changes her state from being hungry to being comfortably full?
Anne may say that she needs a certain number of calories, let’s say 600 kcal, in her lunch to feel comfortably full, or satiated.
Now, I say that this is a fundamental misunderstanding of how our body regulates hunger and satiety. Research shows very clearly that how much we eat in a meal is only partly related to how many calories that meal contains. For example, let me create three different lunches, let’s call them lunch A, lunch B, and lunch C. I’ll tell you later what these meals may look like and what their characteristics are. For now, let’s just say we have three very different meals, and let’s say I conducted a research study and served each of these to Anne on different days, in random order. Each time, I would ask her to eat until she was comfortably full. Now, what is interesting is that she wouldn’t necessarily eat exactly 600 kcal of each meal. The data that I am going to share with you later in this blog post suggests that she may eat 500 kcal of lunch A, 800 kcal of lunch B, and 1100 kcal of lunch C. So she’d eat more than twice as many calories if she were served lunch C compared to lunch A, even though she ate to satiety each time.
Now, if Anne usually eats meals that are similar to lunch C, she will gain weight. If she wanted to lose that excess weight, she may think that the solution is to count the calories she is eating, and reduce her calorie intake by some amount. For example, she may decide to continue eating her normal lunch C, but only half of it, because her calorie counting has shown that half a portion would be a more reasonable number of calories. And for sure, in the short term, this may work, and Anne may lose a few pounds.
The problem is, this never works in the long term, because there is a reason she eats 1,100 kcal of lunch C: lunch C is not very satiating per calorie, meaning she spontaneously eats a lot more calories to feel the same level of satiety as with lunches A and B. So if she only ate half of lunch C regularly, she’d feel hungry all the time, which would make her miserable and very difficult to stay on this diet for an extended period of time.
Understanding why Anne eats such different amounts of calories depending on whether she eats lunch A, B, or C holds the key to understanding why we overeat, and also how we can lose weight and have a chance to keep it off. Anne gained weight because she ate foods that were not very satiating per calorie, so she needed to eat more calories to feel comfortably full. So, of course, the number of calories she ate matters, but the solution is not to count calories and consciously cut calories. Anne should not focus on calories at all, but instead CHANGE THE TYPES OF FOODS she eats. Because the foods she ate were the problem in the first place.
There are three key characteristics that determine how satiating a food or a meal is per calorie, and that’s what we are going to discuss in this blog post. Let’s get started …
Satiety Factor #1: High Protein Content
Remember the last blog post in which I shared that if you sit down to eat a meal, you are going to eat significantly more calories overall if that meal includes an alcoholic or sugar-sweetened beverage.
This here is the opposite of that. We know that if you sit down to eat and the meal has a high content of protein, you will require fewer calories until you stop eating because you are comfortably full. More specifically, a meal with a higher percentage of total calories as protein is more satiating.
This is nicely apparent here in this meta-analysis, meaning a study of studies. These authors combined data from 44 published feeding studies in which participants ate diets differing in the relative amounts of protein, carbohydrates, and fats. In all studies, the investigators measured total energy intake, in calories, from protein and fat, shown on the y-axis in the figure above. The x-axis shows the percent protein relative to total energy intake. Each dot is actually the average from a group of participants from one specific diet in one of these 44 studies, so this graph represents data from thousands of individual participants. What we can see nicely in the red dots is that across these studies, participants ate fairly similar amounts of calories from protein, independent of the protein content of the diet. Natural human diets tend to almost always provide 10 to 30 percent of total calories in the form of protein. And what you see is that no matter how low or how high the protein content in these test diets was, participants always ate around 400 or 500 kcal worth of protein per day. There may be a tiny increase in absolute protein intake with higher-protein diets, but considering that protein percentage is tripling here between the extremes, the difference in calorie intake from protein is negligible. Given that protein has 4 kcal per g, that means participants across these studies aimed to consume around 100 to 125 g of protein per day. And whenever the protein content in the diet was low, such as 10 or 12 percent of total calories here, participants needed to eat more food and more calories to reach this 100 – 125 g of protein intake per day, compared to when the protein content of the diet was high, say 25-30% of total energy. See these blue dots here now, these represent total calorie intake on these diets. And we can see clearly that participants tended to eat more calories overall whenever the protein percentage of the diet was low. One way to think about this is that whenever protein is ‘diluted’ by fat or carbohydrates, the overall food intake increases to keep protein intake stable, or to reach a specific protein intake target.
These data are in line with the protein leverage hypothesis by my colleagues, Drs. David Raubenheimer and Stephen Simpson, who have proposed that organisms, including humans, do not just have an appetite for calories, but also for protein. Throughout their careers, they have assembled quite a bit of data in support of their hypothesis. They were able to show that a wide variety of species ranging from fruit flies to insects to all kinds of mammals, tend to eat more calories whenever the protein content of their food is low.
If we tend to spontaneously eat less food and fewer calories if our diet has a higher protein percentage, then we should be able to lose weight more easily on such high-protein diets. And looking at the data, I’d say we have moderate support for this idea, with several studies showing greater reductions in body weight or fat mass in participants following a high-protein diet compared to a low- or medium-protein diet. The biggest issue in some of these studies is poor compliance. In many studies, people were unable or unwilling to follow a high-protein diet for an extended period of time, and substantial weight loss was seen only in those who were able and willing to stick to the high-protein diet in the long-term. Some long-term studies found no difference in weight loss between high-protein and standard-protein diets, but a greater loss of body fat mass or a greater preservation of lean mass.
The lessons we can learn here from the scientific literature are that a protein-rich diet reduces calorie intake, and probably also is more effective at reducing body weight and fat mass in the long term than a low-protein diet IF we are able to stick with it. High-protein diets can also help with weight loss by mildly increasing energy expenditure, and there are also data to suggest that they can attenuate some of the negative effects of weight loss, such as a loss of muscle mass and constant hunger.
However, if we go back to this diagram above, pay attention to the blue dashed line. That line summarizes the average calorie intake at every level of protein intake across all of these studies. The first thing to take note of is that, on average, spontaneous calorie intake goes down when protein percentage goes up. The second point, however, is that at any given level of protein intake, there is a lot of variation in calorie intake. Right? According to these data, some people who were served diets containing 17% of energy from protein ate around 1,500 calories per day from fat and carbohydrates, while others ate about 3,500 calories per day from fat and carbohydrates. That difference is explained by other characteristics of these diets, some of which we’ll address later in this blog post, while others will be covered in the next blog post. Suffice it to say that protein is just one of many factors that explain how much we eat.
But it is an important one, so what do I concretely suggest? Well, let’s stick with this diagram above and we see that increasing protein intake is particularly important at the low end of protein percentage. Increasing the protein percentage of your diet from 10 to 15% would have a dramatic effect on calorie intake in the average person, all else being equal. So my strongest recommendation is that if you currently eat a diet that is very low in protein, which may be the case for those of you who eat a lot of ultra-processed foods or who are vegetarian or vegan, try to make sure that you incorporate at least a small serving of a protein-rich food in every meal you eat. Specifically, if you regularly eat a meal that consists mostly of ultra-processed foods, refined grains, and added sugars, such as a breakfast of toast with jam, or sugary cereal with milk, even though the milk has a bit of protein, these types of meals tend to be quite low protein. I think here you would see the greatest improvement in how satiating your diet is if you totally or at least partially replaced these types of foods with a high protein food.
In general, I think it’s reasonable to aim for at least around 20 to 25 g of protein per meal if you are a small lady, or 40 to 50 g per meal if you are a large gentleman. That would translate to a protein content of 18 to 20% of your total calorie intake. A bit more would be fine as well, but I think that getting up to that level would make your diet as a whole a lot more satiating if you are currently getting less than that. Now, what does 20 to 25 g of protein, or 40 to 50 g of protein look like?
I’ve made this little poster above that shows the amounts of different protein-rich foods you would need to eat to get 10 g of protein. Just an ounce or two of most meat or fish. A couple of eggs or three to four ounces of cottage cheese or Greek yogurt. Legumes sich as lentils, beans, or soybean products such as tofu are other great sources. Nuts are as well, but just like full-fat cheese, nuts have one characteristic that makes these less ideal for what we are discussing here, namely how to maximize satiety per calorie. We’ll get back to this later in this blog post.
I have included this sheet in the downloadable PDF file showing the satiety scores of common foods.
Satiety Factor #2: High Fiber Content
Just like what we discussed for protein, spontaneous calorie intake tends to be lower when a meal is high in fiber compared to a similar meal low in fiber. This short-term effect translates to less weight gain or even weight loss over time when people eat high-fiber diets, in most studies at least.
There is some inconsistency in the literature because most randomized controlled trials in this field used a specific fiber supplement, and some types of fiber seem to be more effective at helping reduce calorie intake and body weight than others. But in general what the data suggest is that soluble fibers and specifically viscous fibers are most effective at lowering calorie intake and body weight. Examples of foods rich in soluble fibers include vegetables, fruit, berries, legumes such as lentils and beans, and whole grains. In general, these are also the types of foods with the highest total fiber content, so I think it’s easiest to simply eat more fiber overall, from a variety of sources. That’s not to say I am strictly against using fiber supplements; they can have their place. However, I don’t think it’s a healthy approach to eat a poor diet and then try to make up for that by taking a bunch of supplements. So I recommend incorporating a variety of whole, ideally unprocessed or minimally processed whole foods rich in different kinds of fiber into our diet, ideally into every single meal.
I have again prepared a little poster (above) that shows some of the most fiber-rich foods, with information on how much of each you’d have to eat to get 5 g of total fiber. Among the most fiber-rich foods are fruit and particularly berries, non-starchy vegetables, but also – not shown here – some starchy vegetables such as carrots, squash, or beets. Then mushrooms in general, and particularly legumes such as lentils and beans, as well as whole grains. Nuts also have quite a bit of fiber, but again let me emphasize that nuts are not so great in another way, as we’ll discuss next.
Satiety Factor #3: Low Energy Density
Energy density is the number of calories per gram of a food, or a meal. So a pure oil or fat, or a pure starch or sugar, will have a lot of calories per gram. Specifically, 9 kcal per g for a fat or an oil, and 4 kcal per g for a carbohydrate such as starch or sugar, and also for a pure protein. Now, I like to express energy density as kcal per 100 g of a food, just because it’s a bit more intuitive to think about 100 g of a food than 1 g portions.
Foods can have an energy density between 0 kcal per 100 g for water and 900 kcal per 100 g for a pure oil or fat. Mostly, foods will have a high energy density if they are low in water and high in carbs, protein, and particularly fat.
And that brings us back to nuts and seeds. I mentioned earlier that these are rich in protein and also in fiber, but that they have another characteristic that makes them less ideal for the purposes of maximizing satiety per calorie. And that characteristic is a very high energy density. Almonds, as one example, have an energy density of 587 kcal per 100 g, because they have almost no water and a lot of both fat and protein.
Imagine you wanted a little snack. You could have a few almonds or a bowl of Greek yogurt with half a pound of strawberries (see figure below). Both of these options have about 200 kcal. But have a guess what would leave you more full, for longer?
The research on this topic is more than clear. To date, there have been at least 38 randomized controlled trials investigating the impact of eating meals with a high energy density compared to meals with a low energy density. And extremely consistently, people eat a lot fewer calories without being asked to restrict their food intake whenever the meals have a low energy density. In fact, studies show that the weight of the food we eat in a meal tends to be roughly the same, so as the energy density of a meal increases, there is a linear increase in calorie intake in that meal. If we compare complex meals across all of the available studies, we can say that if one meal has an energy density that is 100 kcal per 100 g higher than the other, then on average, people will eat about 260 kcal more of that one meal. At a difference of 50 kcal per 100 g, the difference in the ad libitum calorie intake at one meal averages 155 kcal. The figure below is based on all available randomized controlled trials and shows the average differences in energy intake in a single meal when comparing the energy density of two different meals (compare to figure 6B in this paper). During a full-day of eating high-energy dense meals compared to low-energy dense meals, the differences are even larger. For example, eating meals that on average have an energy density just 25 kcal/100 g lower reduces the daily calorie intake by 400 kcal. These are huge effects, so we can assume that even a small difference in energy density will have a large impact on calorie intake and body weight in the long term. It’s therefore not surprising to find that randomized controlled trials do consistently find that people lose weight when they are randomized to a diet characterized by a low energy density.
Foods with a high-energy density include all of those that have little water and a high content of fat and/or sugar. First and foremost, this applies to most ultra-processed foods, you know all of the packaged stuff that doesn’t contain individual foods but isolated components of foods, such as high-fructose corn syrup, sugar, and added fats and oils, usually with a cocktail of artificial colors, flavors, binding agents, emulsifiers, and so forth. These include most things in packages from the middle of the grocery store, such as chips, sugary breakfast cereals, packaged doughnuts or cookies, frozen pizza, ice cream etc., Quite energy dense are also some natural or minimally processed foods such as nuts and seeds, cheese, and most processed or very fatty meats such as salami or bacon.
Foods that have low energy density are those whole foods that contain a lot of water and not all that much fat or sugar. Vegetables of all kinds, leafy greens, legumes, mushrooms, fresh fruit and berries, and all lean types of fish, seafood, and meat tend to have a fairly low energy density.
These are what I would consider the three most important factors that make a meal more satiating per calorie: a high protein content, a high fiber content, and a low energy density. Each factor by itself can make a meaningful impact on how many calories we eat in a given meal, but they are most powerful if combined together.
The Nourished by Science Satiety Score
I’ve tried to make this very simple. The satiety scores range from 0 to 100, with zero indicating very low satiety per calorie and 100 indicating high satiety per calorie. To clarify, 0 does NOT mean you will never get full from the food. It just means you will eat many more calories before you feel full than if you eat a higher satiety-score food.
For example (see figure above), let’s assume you ate either one small bowl, 100 g, of boiled potatoes. And another day, you ate a small bowl, again 100 g, of French Fries. You would probably argue that French Fries are more satiating, more filling, and you would be correct. 100 g of French fries have 323 kcal, whereas 100 g of boiled potatoes have 78 kcal. So of course, you would feel more full after eating the French fries, because that difference is huge. However, if we calculate the satiety score based on protein content, fiber content, and energy density, boiled potatoes have a satiety score of 66 while French Fries have a satiety score of 20. What this means is that the data tell us that boiled potatoes are much more satiating per calorie consumed and that if you included boiled potatos in a meal, you’d likely eat less calories overall than if your meal contained French Fries. Because, after all, to get 323 kcal, you only need 100 g of French Fries, but you could have more than 4 bowls of boiled potatos. So, in other words, foods with a high satiety score generally are expected to spontaneously lower our overall calorie intake, without us counting calories or paying any attention to calories, while foods with a low satiety score would be likely to lead to a higher calorie intake. Hope this makes sense.
Let’s review the satiety scores of a few common foods.
We find the lowest satiety scores among oils and fats, as well as sugar, syrups and other such sweeteners, including honey. These all have extremely low satiety scores between 0 and 13. It’s probably not surprising that we also find extremely low scores in foods that are rich in fat and/or sugar, such as mayonnaise, salad dressings, potato chips, French Fries, doughnuts, ice cream, and candy bars. All of these have in common that they are low in protein, low in fiber, and have a high energy density, mostly because they have little water and a lot of fat, starch, and/or sugar.
Sugary beverages do look reasonably good by comparison, with satiety scores around 30. However, as we discussed in the last blog post, sugar in the form of beverages is in a category of its own and absolutely raises calorie intake and body weight. So mentally, we should downgrade sugary beverages and also alcoholic beverages some more, simply because the evidence clearly suggests that liquid calories are less satiating than calories from solid foods.
Many of the low-satiety score foods are those that we would consider treats. And as long as we eat them only occasionally and in moderation, they are fine in the context of an overall highly satiating diet, if you are the type of person who can actually keep the consumption of these foods moderate. There are some people who just cannot resist the lure of ice cream, candy, or potato chips, and they need to cut them out entirely for some time and never buy them.
Salad dressings and condiments are probably fine in small amounts as well if they are eaten with a higher satiety score food. As an aside, I recommend home-made salad dressings rather than store-bought ultra-processed dressings that typically contain many unnecessary ingredients.
Generally a bit higher scores can be found among nuts and seeds. These are also very energy-dense, as we discussed, but they are also fairly rich in protein and fiber. Let me say clearly that I am not against nuts and seeds, but it is important to be clear how energy-dense they are. Personally, I love Macadamia nuts and almonds, and could easily eat 800 or 1000 kcal of these before even considering that I may have had enough.
Very high in fat and therefore with a high energy density are also many processed meats or very fatty cuts of meat, such as salami, liverwurst, ham, bacon, or many types of sausage such as bratwurst. Mostly, these have satiety scores between 15 and 30 here, which is not great.
Now, let’s take a look at the other end of the spectrum. We find the highest satiety scores among non-starchy vegetables, mushrooms, and leafy greens. Maybe you would argue that these kinds of foods are not very filling. And, of course, they are not. No one who is very hungry will be happy to be served a bowl of fennel. But relative to their extremely low calorie content, they are much more filling than most other foods. In other words, if you had a meal of, say, meat and potatoes, by themselves, you would eat a lot more calories than if you first had a salad and then served some mushrooms and broccoli with the meat and potatoes.
Also among the high-satiety foods are starchy vegetables, which have a higher satiety score if they are boiled in water as opposed to baked, simply because baking removes some of the water and makes the food more energy-dense. Still, both boiling in water and baking are both highly preferable to frying in oil. See the difference between boiled potatoes, baked potatoes, and French fries, as we discussed earlier.
Very high-satiety foods are also legumes, such as beans and lentils, and all kinds of fruit and berries. Berries, in general, have a higher satiety score because they are extremely rich in fiber and have a very low energy density. We also find high or very high satiety scores in fish and seafood and unprocessed meats. Important here is that they are not breaded and deep fried, but simply cooked or grilled. Frying in a bit of fat is certainly an option, but that would lower the satiety score, depending on how much fat is added.
Eggs and particularly egg white, as well as Greek yogurt and also cottage cheese, have very high satiety scores. The higher-fat dairy products have a lower satiety score, with full-fat cheese having mostly lower scores. As with nuts and seeds, I wouldn’t suggest that no one should ever eat cheese, but again I do think it’s important to keep in mind how energy-dense cheese is and to pair it with other, more high-satiety foods.
We find middling satiety scores among grains. Generally, the satiety scores of whole grains are a little bit higher than those of refined grains, because of their higher fiber content. And grains that are cooked by boiling in water, such as rice or quinoa, tend to have a higher satiety score than those that are baked. That’s due to a difference in water content and energy density.
I have created this, and similar posters, not so that you’ll need to first consult several posters whenever you want to eat something. These are meant as learning tools, for you to concretely understand a fundamental issue so that later you can intuitively apply it. If you would like to download a high-resolution copy of the poster, please click here.
Let’s wrap this up by going back to Anne and the example lunches A, B, and C we talked about earlier. Remember that Anne doesn’t count calories or even care about calories, she just grabs whatever lunch she can get, and eats until she is comfortably full. I claimed that depending on which foods Anne chooses to eat, she will eat vastly different amounts of calories. In this made-up example, I suggested that she may eat anywhere from 500 to 1,100 kcal in one meal. Now, what would such meals look like that trigger low vs. high-calorie intake?
Well, if we use the satiety scores to design these meals (see figure above for an example), then meal A may consist of a grilled chicken breast with some broccoli, cooked quinoa or rice, and some fresh fruit or berries for dessert. Overall, this meal has a very high satiety score of 73, and the key point to understand here is that even if Anne had access to unlimited amounts of this meal, she would have a hard time overeating calories because of the specific properties of these foods. They are very rich in protein, fiber, and have a very low overall energy density. So if she just ate until she was comfortably full, she may eat somewhere around 500 kcal.
Lunch B may consist of a lasagna with cheese, a small tomato salad, and a chocolate pudding for dessert. Now, this is still a pretty good meal, with an overall satiety score of 48, but it does contain some lower satiety-score foods, such as cheese and pudding. My educated guess is that Anne may eat quite a few calories more of this meal than of meal A, maybe around 800 kcal.
And then lunch C would be a typical fast food dish of a cheeseburger, some fries with ketchup, and a doughnut for desert. This meal includes almost only low satiety foods, and again, if Anne could eat unlimited amounts of this until she was comfortably full, I think it’s not unreasonable to think she may well eat more than 1,000 kcal of these foods. If she had a sugar-sweetened soda with this meal, as is so often the case with fast food meals, her calorie intake may go up even more. Because remember from the last blog post, liquid calories are mostly just added on top of solid food calories.
Summary & Conclusion
Taken together, one key to a healthy body weight is to maximize satiety per calorie consumed, helping us eat fewer calories while still eating until we are comfortably full.
Three key characteristics that make foods or meals or diets more satiating are a higher protein content, a higher fiber content, and a lower energy density. While each individually lowers ad libitum calorie intake and body weight in clinical studies, combining the three could have a very meaningful impact on the weight trajectory in the long term. For anyone who wants to prevent weight gain, I would suggest eating mostly foods with a satiety score of 30 or higher. In other words, to be very careful with those low satiety index foods listed on page 2 of the satiety score poster. For anyone who is overweight and wants to lose some weight, I would suggest focusing on foods with a satiety score of around 40 of even 50 and higher, and being really careful with added oils and fats, added sugars, and condiments and dressings. As long as you eat the right foods, eat until you are comfortably full, and find a way of eating you are totally happy with in the long term, I do think this is a way of eating that most people can sustain in the long term because there is no calorie counting, hunger, or constant food restrictions.
By the way, when I picked these three factors, I also considered effects other than those on calorie intake and body weight. For example, as we discussed in the blog post on avoiding blood sugar spikes, including some protein or fiber-rich vegetables in a highly glycemic meal has the potential to reduce the increase in blood sugar levels after the meal. A higher protein intake also may reduce the loss of muscle mass during weight loss. Similarly, a higher fiber diet usually requires that we eat more unprocessed foods such as vegetables, fruit and berries, legumes, nuts and seeds, and whole grains, all of which are also rich sources of micronutrients such as vitamins, minerals, and trace elements.
Now, maximizing satiety per calorie is only the first key to a healthy body weight. In the next blog post, we will discuss the second key to a healthy body weight, which is to minimize factors that trigger overeating.
How I use this Information
I can honestly say that I have never counted calories, and don’t even know how many calories I eat on a regular basis. I simply make sure that most of my meals have characteristics that make it less likely that I’ll overeat. With regard to the satiety factors discussed in this blog post, I mostly try to incorporate a little bit of protein in each meal, be it a piece of meat, some fish, some eggs, or some legumes such as lentils and beans. Most of my meals are also very rich in fiber from sources such as vegetables, leafy greens, salads, fruit, berries, or legumes. Sometimes some whole grains, but I have celiac disease and don’t eat all that many grains.
Now, you may think that as a professional nutrition researcher, I only munch on super healthy stuff all day, like a lunch of broccoli with some cauliflower and a side of kale, with a bowl of spinach for dessert. That is not true at all. I do eat well and without depriving myself. True, the high-satiety foods that are also highly nutrient-dense shown on the first page of the satiety score poster form the backbone of my diet, and most meals largely consist of some combination of foods from this page. But that gives me the freedom to also include other foods that I really enjoy. For example, I enjoy adding some cheese to an omelet or some feta cheese to a salad, and I almost always add some olive oil or butter to a vegetable dish, or nuts and seeds to a bowl of Greek yogurt or a salad. And as an occasional treat, I don’t see what’s wrong with a piece of apple pie, some dark chocolate, or a small bowl of ice cream every once in a while. I just try not to make any of these a regular habit, but enjoy them as an occasional special treat.
All of this is to say: you probably do not have to be perfect and maximize all of these factors at every meal. My philosophy here is that if we incorporate some of these factors into most of our meals, that will do wonders to our long-term weight trajectory while still leaving some room for some treats and just an uncomplicated enjoyment of the food we are eating. If then we also combine this knowledge about the satiety index of foods with what we will discuss in the next blog post and minimize known factors that trigger overeating, I think we can say goodbye to calorie counting and just eat a variety of the foods we like until we are comfortably full.
Again, if you’d like a copy of the satiety score poster, please click this link here.
Take care.
Frequently Asked Questions (FAQ)
March 8, 2024
Q: Do we have evidence that a satiety approach works better for weight loss than calorie counting? Do I discourage calorie counting?
The traditional approach to weight loss has been focussed on actively restricting calorie intake combined with food tracking (i.e., “calorie counting”). Indeed, more meticulous food tracking or calorie counting is commonly strongly associated with greater weight loss in weight loss studies.
In other words, calorie counting is indeed an evidence-based approach to weight loss. So why do I suggest in this blog post not to track calorie intake, and instead to focus on changing the types of foods eaten?
First, the scientific evidence linking food tracking and calorie counting to weight loss is, in my opinion, weak. While it is indeed based on numerous randomized controlled weight loss trials, none of these trials compared identical interventions with versus without food tracking and calorie counting. Instead, food tracking and calorie counting were associated with weight loss in secondary analyses in most of these studies. This is a much more limited approach, and concluding from these associative data that food tracking and calorie counting cause greater weight loss is not justified. It is at least as likely that better adherence to food tracking or calorie counting is a marker for greater motivation to lose weight or better adherence to the weight loss intervention as a whole. Thus, in my interpretation of the literature, the evidence supporting an effect of tracking food and calorie intake on body weight is weak.
Second, in the long term, food tracking and calorie counting place a heavy burden on an individual, both in terms of time and their relationship to food. My philosophy is that ‘health’ is not simply the freedom of physical illness, but also psychological and mental well-being. As I functioned as the Principal Investigator of a clinical study in young women with Anorexia Nervosa in the past, I have experienced firsthand the tremendous damage of a societal and scientific approach to body weight that considers calories and food as an enemy that needs to be cut out, or minimized. There are also some data linking calorie counting and food tracking to restrictive eating disorders; however, these data are mostly associative, and – again – a cause-and-effect relationship remains unclear. Still, whether or not calorie counting contributes to the development of disordered eating or eating disorders, I strongly prefer a positive approach to foods as a means of nourishing our bodies. Admittedly, let me be very clear that this point is informed to some degree by my beliefs and attitudes, rather than scientific evidence, and I absolutely accept that my position here is not the only correct one.
Third, tracking calorie intake makes sense mostly if we believe that excessive calorie intake is the root cause of weight gain. This is not my position. Of course, I am not denying that weight gain is the result of excessive calorie intake. However, I see excessive calorie intake as a mediator in this relationship, not the root cause. In other words, the important question here is WHY we overeat. As summarized in the figure below, there is ample evidence showing clearly that calorie intake is strongly related to the degree to which food is satiating per calorie, to other factors that cause us to overeat, and to numerous psychological factors. Many of these factors and their relationship to calorie intake and body weight are well understood, and we also have solid scientific evidence that addressing each of these root causes can lower calorie intake and body weight. I propose that identifying and addressing the root causes of overeating in a given individual is a more promising approach to a long-term healthy body weight than calorie counting, while also offering an opportunity to repair our often suboptimal relationship with food.
Now, all of that said, if someone practices food tracking and calorie counting and it works for them, I am certainly not against the practice per se. I am simply suggesting that it is not necessary and by itself, i.e., without addressing the root causes of overeating, probably not effective in the long term.
Q: Is “low energy density” or “low satiety score” another way to say “low fat”? Is a high-satiety diet always low in fat and high in carbs?
For sure, foods that are very high in fat or oil will have a high energy density and a low satiety score, unless they are also rich in protein and/or fiber. However, the way I calculated the subscores for energy density, high-fat and high-sugar or high-starch foods will have similarly low satiety scores, simply because all of these foods have extremely high energy densities.
Maybe more importantly, eating a diet characterized by a high satiety score can be implemented on any type of diet. For example, on a ketogenic diet, someone could mostly choose to eat unprocessed meat, fish and shellfish, eggs, and Greek yogurt with side dishes of salads, leafy greens, and non-starchy vegetables. The animal foods in that diet all contain mostly protein and fat, yet still have high or very high satiety scores. Vice versa, a low-fat plant-based vegan may choose to eat mostly legumes, cooked whole grains, vegetables, fruit and berries, and have a similarly high satiety score. In other words: the satiety score is not necessarily linked to the macronutrient composition of the diet.
Q: If added fats and oils have a satiety score of zero, do I suggest that all meals should be prepared without added fats?
No, of course not. It is important to enjoy our food. It is possible to include some (smaller amounts) of low satiety score foods in a meal, and we should consider the satiety score of the overall meal. Choosing ingredients with high satiety scores, such as vegetables, greens, legumes, fish, seafood, or unprocessed meats provides some freedom to add oil, fat, sugar, or starch to a meal, and as long as we don’t overdo it, the satiety scores of the entire meal can still be high.
For example, preparing 10 oz (300 g) of broccoli with 1 tablespoon of olive oil (15 g) would result in a satiety score of 60 for the whole dish, which is still very high. Adding 2 tablespoons of olive oil (30 g) to 10 oz of broccoli (300 g) would lower the satiety score of the dish to 46. That’s still pretty good. However, adding 4 tablespoons of olive oil (60 g) to 10 oz of broccoli (300 g) would lower the satiety score to 32, which is no longer so great.
In my family, we almost always enjoy our cooked or roasted veggies with some butter or olive oil, and we certainly add salad dressings such as a vinaigrette to our salads. However, it can make a significant difference if we are careful not to add too much oil or fat.
Q: How is the satiety score based on protein, fiber, and energy density related to empirical satiety ratings of foods?
Great question. I was curious about that myself, so I took the Nourished by Science Satiety Scores of 20 foods and compared them with the satiety index of these 20 foods, as determined by Holt and colleagues. These investigators fed 240 kcal portions of different foods to groups of participants, and asked them to rate their own level of satiety for 120 minutes afterwards. The satiety index was calculated from the area-under-the-curve of the subjective satiety ratings, relative to that of white bread, which was set to 100.
The figure below shows the Nourished by Science satiety scores on the x-axis and the Holt et al. satiety index for the foods on the y-axis. With the exception of boiled potatoes and lentils, the score and the index correlate highly (r2=0.487).
While Holt and colleagues showed that a higher satiety index was associated with lower ad libitum calorie intake at a subsequent meal, the long-term relevance of their satiety index is unknown, as no long-term body weight data exist for people eating high versus low satiety index diets. Also, the satiety index has very limited usefulness, because it has not been determined for the vast majority of foods. By contrast, the Nourished by Science satiety scores can be calculated for any food, meal, or diet.
Q: What if I cannot tolerate a high-fiber diet?
The satiety score is based on three factors, and foods have a high satiety score if they have a high protein content, a high fiber content, and/or a low energy density. Thus, even if someone cannot consume a high-fiber diet, they could choose high-satiety foods with a high protein content and/or low energy density, including fish and seafood, unprocessed meats, eggs, Greek yogurt, or leafy greens and salads. That could be a nutrient-dense, highly-satiating diet for the long term. An alternative would be to experiment with small servings of fiber-rich foods such as different types of vegetables, nuts and seeds, whole grains, and even legumes, with the goal of gradually increasing consumption of those high-fiber foods that are tolerated well.
Q: Why is the satiety score of nuts so low? Some nutritionists suggest that nuts do not increase overall calorie intake and weight gain, partly because the fat in nuts is not fully absorbed.
It is important to be clear that a composite score such as the Nourished by Science satiety score has some limitations. The satiety score is based on three key characteristics that have been shown to reduce calorie intake in the short- and long-term and to reduce body weight and/or fat mass. Applying these factors to any given food can help us estimate the impact of that food on satiety, calorie intake, and body weight. However, for each food, there will be additional food-specific factors that can affect the impact of that food on calorie intake and body weight.
With regard to nuts, the satiety scores are relatively low because of the very high energy density of nuts. This would suggest that excessive consumption of nuts could lead to increased energy intake. This is actually consistent with the available evidence from 31 randomized controlled trials showing an increase in calorie intake in intervention diets containing nuts vs. no nuts. However, randomized controlled trials also demonstrate that nuts do not affect body weight, because body weight does generally not differ in intervention diets containing nuts as compared to no nuts. It is thought that this lack of weight gain is commonly explained by other characteristics of nuts. Specifically, nuts are hard-textured foods that require a lot of chewing, which seems to protect against the overconsumption of calories. Also, because of what we call food matrix effects, the calories from a whole food such as nuts are less bioavailable than from a processed food such as an oil or a sugar. It has been determined that the energy bioavailability of different types of nuts is 6-21% lower than their absolute content of macronutrients suggests (in other words: we do not absorb all of the fat in whole nuts).
Taken together, nuts do have characteristics, specifically a high energy density, that suggests that a diet rich in nuts may increase calorie intake. However, nuts also have characteristics such as their hard texture and the lower bioavailability of nut calories, that seem to counter any undesirable impact of nuts on body weight. The importance of these factors in the regulation of energy intake and body weight will be discussed in future videos. However, in hindsight, the inconsistency between the satiety score of nuts and the long-term body weight data should have been briefly mentioned already in this video and blog post, and I apologize for any confusion this may have caused.
References
- Raubenheimer and Simpson. Protein appetite as an integrator in the obesity system: the protein leverage hypothesis. Philosophical Transactions of the Royal Society B 2023; 378: 20220212.
- Magkos. The role of dietary protein in obesity. Reviews in Endocrinology and Metabolic Disorders 2020; 21: 329-40.
- Leidy et al.; The role of protein in weight loss and maintenance. American Journal of Clinical Nutrition 2015; 101: 1320S-9S.
- Jesudason et al.; Weight-loss diets in people with type 2 diabetes and renal disease: a randomized controlled trial of the effect of different dietary protein amounts. American Journal of Clinical Nutrition 2013; 98: 494-501.
- Krebs et al.; The Diabetes Weight Loss (DEWL) Trial: a randomized controlled trial of high-protein versus high-carbohydrate diets over 2 years in type 2 diabetes. Diabetologia 2012; 55: 905-14.
- Sacks et al.; Comparison of weight-loss diets with different compositions of fat, protein, and carbohydrates. New England Journal of Medicine 2009; 360: 859-73.
- Due et al.; Effect of normal-fat diets, either medium or high in protein, on body weight in overweight subjects: a randomized 1-year trial. International Journal of Obesity and Related Metabolic Disorders 2004; 28: 1283-90.
- Bray et al.; Markers of dietary protein intake are associated with successful weight loss in the POUNDS Lost trial. Clinical Obesity 2017; 7: 166-75.
- Evans et al.; Effects of protein intake and gender on body composition changes: a randomized clinical weight loss trial. Nutrition & Metabolism 2012; 9: 55.
- Tang et al.; Normal vs. high-protein weight loss diets in men: effects on body composition and indices of metabolic syndrome. Obesity 2013; 21: E204-10.
- Leidy et al.; Higher protein intake preserves lean mass and satiety with weight loss in pre-obese and obese women. Obesity 2007; 15: 421-9.
- Halton and Hu. The effects of high protein diets on thermogenesis, satiety and weight loss: a critical review. Journal of the American College of Nutrition 2004; 23: 373-85.
- Reynolds et al.; Carbohydrate quality and human health: a series of systematic reviews and meta-analyses. Lancet 2019; 393: 434-45.
- Thompson et al.; Effects of isolated soluble fiber supplementation on body weight, glycemia, and insulinemia in adults with overweight and obesity: a systematic review and meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition 2017; 106: 1514-28.
- Wanders et al.; Effects of dietary fiber on subjective appetite, energy intake and body weight: a systematic review of randomized controlled trials. Obesity Reviews 2011; 12: 724-39.
- Jovanovski et al.; Can dietary viscous fiber affect body weight independently of an energy-restrictive diet? A systematic review and meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition 2020; 111: 471-85.
- Robinson et al.; Calorie reformulation: a systematic review and meta-analysis examining the effect of manipulating food energy density on daily energy intake. International Journal of Behavioral Nutrition and Physical Activity 2022; 18: 48.
- Klos et al.; Impact of energy density on energy intake in children and adults: a systematic review and meta-analysis of randomized controlled trials. European Journal of Nutrition 2023; 62: 1059-76.
- Rolls. The relationship between dietary energy density and energy intake. Physiology and Behavior 2009; 97: 609-15.
- Burke et al.; Self-monitoring in weight loss: a systematic review of the literature. Journal of the American Dietetic Association 2011; 111: 92-102.
- Holt et al.; A satiety index of common foods. European Journal of Clinical Nutrition 1995; 49: 675-90.
- Akhlaghi et al.; Effect of nuts on energy intake, hunger, and fullness: a systematic review and meta-analysis of randomized controlled trials. Critical Reviews in Food Science and Nutrition 2020; 60: 84-93.
- Baer et al.; Nuts, energy balance, and body weight. Nutrients 2023; 15: 1162.
12 Responses
What about people who do really well by counting calories – eg me? Why is your anecdote better than my anecdote (which BTW seems to have not-just-me evidentiary backing from eg LookAHEAD).
Do you have any actual evidence that an SPC approach works better for some substantial population than calorie counting?
Are you going to publish details of your SPC index calculation? How does it differ from umm what’s-his-name’s, the DietDoctor guy?
Hi Eddy,
I wrote my response to you up in the frequently asked questions section at the end of the blog post:
https://nourishedbyscience.com/satietyscore/
In short, the evidence linking food tracking and calorie counting to weight loss is weak. Specifically, many RCTs that used food tracking or calorie counting also used several other intervention modalities and the relationship with weight loss is based only on associative secondary analyses. By contrast, the satiety scores presented here are based on >30 RCTs for each of the three factors. That said, I don’t have evidence that has tested the satiety score as a whole. Also, I certainly don’t want to convince you to give up counting calories if it works well for you and you are happy with it.
Best,
Mario
Interesting. The “Satiety Score” appears to imply that from a satiety perspective, sugar and olive oil are the same (actually, sugar is a little better).
This has not been my personal experience, presumably because the satiety score ignores the effects of hormones such as insulin and glucagon. Perhaps I am jumping ahead and this will be addressed in a future post. But as is, the Satiety Score should be used with caution.
Great overview, thank you!
I’m curious how fat content plays a role in satiety, particularly 1-3 hours after the meal. It sounds like it doesn’t play a big role in immediate satiety, since studies showed that people ate more calories from meals that were calorie-dense, but I wonder how long they might go until the next meal, or how much they might eat at the next meal. If all meals are low in energy-density, does that prevent overeating later in the day even if overall frequency and/or number of meals increases?
Anecdotally, my experience is that a banana and an avocado (which you gave similar satiety scores) will have vastly different effects in terms of longer-term satiety: if I eat a banana and two eggs for breakfast, I might be hungry again in an hour, while an avocado and two eggs for breakfast will usually keep me going until lunchtime. Out of curiosity, comparing 100g servings of each (using the Nutrition Comparison Tool on myfooddata.com), a banana is about half the calories, half the protein, and about a third the fiber of an avocado — and of course, about 2% the fat content of an avocado.
Is the similar satiety score you gave them based on equivalent calorie servings, maybe? They do look much more similar in terms of protein and fiber when I change the comparison to 200cal servings instead of 100g servings. Of course, most people who aren’t weighing their food would likely eat one banana (136g, 121cal) or one avocado (201g, 322cal), so the comparisons change again in light of real-world serving scenarios.
I am sorry that this is confusing, but the satiety scores should not be seen as a measure of how satiating a food is, but of how satiating a food is relative to the calories it contains. Specifically, fat certainly is very satiating, but it also comes with a lot of calories. Given that 100g of avocado has about twice as many calories as 100g of banana, but a similar satiety score, the score would estimate that 200g of banana would be as satiating as 100g of avocado. Of course, the score can only provide an estimate, because there are other factors that affect food intake than these three factors that went into the satiety scores. And we all are different, so the level of satiety you experience to a food may be different from mine.
Hope this helps.
Cheers
Mario
Thank you for everything you do. I trust you and your honest delivery. Kathy (USA)
Thank you, Kathy.
Dear, Dr. Kratz:
As a subscriber to your YouTube channel and a reader of this blog, I sincerely appreciate your superb content. It’s obvious that you put a lot of time, effort, attention, and detail into everything you do.
Over the past 15 years, I’ve followed a variety of blogs, YouTube channels, and podcasts. Eventually, I realized that I was chasing a lot of fads and being unintentionally misled by well-meaning people who truly believed in what they were promoting, but they didn’t have the necessary education or training to understand or critique the theories they were promoting. They were fooled, too. In other cases, I now believe, some folks were simply leveraging the popularity of health fads, simply to allow them to sell their own related products and services.
It’s taken me time to realize my own biases, my many limitations, my desire to want certain things to be true, and my many attempts to believe in two or more opposing ideas at the same time, despite the empirical evidence in my own life that only one could be true. I’ve read, watched, and listened to so much information over the past 15 years, only to realize that I went from feeling like I knew very little, to feeling like I knew so much, to ending up feeling like I knew even less than when I started.
Over the past year or so, I’ve started over again. While I’ve not been able to forget everything I’ve read, watched, and heard over the years, I now hold the information more loosely and consider them simply as theories or possibilities. Thanks to scientists and educators like you, I’m finding myself less likely to get swayed by my own desire and emotion and to always look for supporting evidence. I’m also getting better at using my own experience and being more honest with myself about those results.
Now, I only look to learn from evidence-based scientists like you. As a result, I find that there really isn’t all that much conflict in what the science shows. When I followed many of the channels/sources promoting fad concepts, there seemed to be more conflicts and cognitive dissonance. Now, that’s not so surprising, since many of those fad ideas weren’t rooted in evidence or science. I feel like I’ve been able to turn down the volume of noise in my head by 85% or more.
Lastly, I’m going on a bit in this feedback for the same reason I really enjoy your content — because most things worth knowing can’t be explained in a 280 character tweet or a 90-second YouTube video. I appreciate that your content isn’t wrapped in loud or jarring music, filled with flashing graphics and jump cuts, or reduced to just telling us what to do. I appreciate longer-form content like yours that not only explains the “What” but also the “How” and “Why.” I find it easier to implement suggestions when I know why I’m doing it and what I might expect along the way.
In closing, there are many of us that greatly respect, value, and appreciate all that you’re doing for the world. You are doing fantastic work and making a real difference in the lives of people!
With admiration,
Irwin
Wow. Thank you for this thoughtful comment, Irwin. Creating content online can sometimes expose the creator to some pretty harsh critiques or even hate comments and emails, most often from someone following the more extreme diet tribes. Therefore, it is wonderful and very welcome to also receive kind and positive feedback such as yours. I certainly know I have a lot to learn in communicating science well and concisely, but it’s good to hear that my style is already resonating with some people.
Best wishes,
Mario
My pleasure, Dr. Kratz. You deserve the acknowledgement and praise. I’m sorry that you sometimes receive hateful feedback from some people. Given how people behave today, though, I’m not entirely surprised.
Luckily, not everyone is this way. For every negative remark you get, there’s probably at least several thousand people who value and appreciate your work. Many of them, however, you’ll never know about, because they don’t comment online or send e-mails. It seems human nature to only provide feedback when it’s negative. Because of this, a content creator’s perspective of their audience might get skewed.
Anyway, you’re doing great work. I hope you continue doing so for a long time, as your perspective is important and very much needed.
Kind regards,
Irwin
Hi, Mario, great content and I find a lot of value in it.
But I absolutely don’t understand, how to calculate satiety score for the mixed dishes. Do we need to take into consideration the food weight?
For example, quinoa, chicken and broccoli 100 g of each and quinoa, chicken and broccoli 200 g of each? Will this dish have the same satiety score of 73?
And example with broccoli with olive oil ( satiety scores 100 + 0), you have satiety scores 60, 46 and 32 depending on the oil, how to calculate this?
Hi Olga,
If you’d like to know more and get access to the spreadsheet to calculate satiety scores of foods and meals yourself, and see exactly how I set this up, I’d be happy to share. Would you complete the contact form on this site, so that I can send you access by email?
What I can tell you already is that the way I computed these is almost certainly not ideal, and may need to be revised at some point.
Thank you for your interest.
Cheers
Mario