The Reason Why a Well-Balanced Breakfast Helps to Prevent Weight Gain


  1. A background of the importance of breakfast in recent years
  2. How eating breakfast affects weight management? My thoughts
     (1) A well-balanced breakfast can help prevent gaining weight
     (2) Lightening your breakfast and lunch makes you more likely to gain weight 
     (3) Skipping breakfast makes it easier to gain weight
  3. Conclusion

In the previous article, I introduced the concepts of a "biological clock," and “chrono-nutrition,” but if you have not read them yet, please read the following article first.
This time, I am going to state my own thoughts on how eating breakfast affects weight management concretely by my intestinal starvation theory. 

[Related article]  
"When to Eat" Is Important, but It Should Be Paired With "What to Eat"


1. A background of the importance of breakfast in recent years

(1) Observational evidence suggests that there is an association of breakfast eaters with lower body weight (lower BMI) compared to non-breakfast eaters.

However, there is little causal evidence to support this conjecture. Observational evidence does not preclude the possibility that breakfast eaters tend to be lower in weight due to other weight-related factors associated with breakfast intake[1].

(2) Short-term studies highlight physiological mechanisms by which breakfast may affect body weight, such as appetite, energy expenditure (metabolism), and fat oxidation. However, whether the proposed physiological mechanisms translate to a long-term effect on energy intake and body weight remains unclear[2].

(3) Some hypotheses with regard to breakfast intake and lower body weight speculate that breakfast intake is important for regulating subsequent energy intake. Some studies have shown that skipping breakfast results in higher energy intake at lunch. On the other hand, others suggest that skipping breakfast may not compensate for a need for increased energy intake later in the day, resulting in a decrease in total daily caloric intake relative to when breakfast is consumed[3].

(4) Public health authorities commonly recommend breakfast intake to reduce obesity.
A randomized controlled trial (RCT) in the U.S. in 2014 tested the effectiveness of a recommendation to eat or skip breakfast on weight loss. Approximately 300 overweight or obese adults who trying to lose weight were randomly assigned to one of three groups (control, breakfast, or no breakfast), and the effect of treatment assignment on weight loss was tested in a free-living setting for 16 weeks.

However, this trial showed no effect of a recommendation to eat or skip breakfast on weight loss[4]. In this RCT, the total daily caloric intake, which foods to combine at breakfast, and the timing of meals, etc. were considered free and not specified.

2. How eating breakfast affects weight management? My thoughts

I think the concept of “chrono-nutrition” is very important in this day and age, but there are many aspects that cannot be explained by metabolism or hormones alone. 

Based on the conventional belief that obesity is caused by "overeating and/or lack of exercise," it does not make sense that people who eat breakfast are associated with lower body weight despite consuming more calories per day than those who skip breakfast. Many researchers try to explain the long-term positive energy effects by looking at how energy expenditure changes over time when breakfast is consumed or skipped, but I think this explanation has limitations.

I believe it makes more sense to explain this with my intestinal starvation theory. Below, I would like to explain it in three different patterns.


(1) A well-balanced breakfast can help prevent gaining weight

Breakfast is the start of the day, and when you eat breakfast, your resting gastrointestinal tract becomes active.

If you eat a variety of food at that breakfast, such as dairy products, fibrous vegetables, seaweed, legumes, and protein, you can prevent intestinal starvation because undigested food will remain in your intestines for around ten hours or so (this is because our intestines are seven to eight meters long). 

Three balanced meals a day

Also, if you eat well both at lunch and dinner, you are less likely to gain weight (meaning that your base weight does not go up), since there is some undigested food remaining over a twenty-four-hour period in your gastrointestinal tract. 

Japanese breakfast

(Typical Japanese breakfast we used to have)

This is the reason why people who are originally slim or medium-sized and have this kind of lifestyle are unlikely to change their body shape throughout their lives, even if they eat without worrying about calories.

However, keep in mind that those who are already overweight will not necessarily lose weight just by eating breakfast (since their base weight is already high).

(2) Lightening your breakfast and lunch makes you more likely to gain weight

On the other hand, breakfast can be fattening (in the sense that it increases one's base weight) even if one eats it. It is a so-called inverted triangle-type diet, in which breakfast and lunch are light (one might even skip lunch) and dinner makes up for the missing nutrients and calories.

light breakfast and lunch

For example, if you just have a light breakfast (a piece of bread, coffee, mashed potatoes, and ham) in the morning, and a rice ball, hamburger, or instant noodles, etc. for lunch, it is easy to induce a intestinal starvation state before dinner, contrary to the situation described in (1) above.

When the gastrointestinal tract becomes active after breakfast, you usually go to the bathroom, and when you do, the only food left in your stomach is what was eaten at breakfast (in this case, mainly carbohydrates and easily digestible protein). 

If lunch is also a simple carbohydrate-based meal and lacks fiber and other nutrients, all the food in the intestines will be digested by dinner, which makes it easier to develop a state of intestinal starvation. 

In short, if breakfast is well-balanced with choices from the various food groups, you are less likely to gain weight, but if it is a simple and unbalanced one, there is a good chance you will gain weight over the long haul. 

Therefore, it is not only a recommendation to eat breakfast, but also eat a well-balanced one that includes fibrous vegetables, protein, and dairy products, etc.

(3) Skipping breakfast makes it easier to gain weight

People who do not eat breakfast may be associated with a nocturnal lifestyle (late night dinner or eating light meals before bed). In short, the main reason for them skipping breakfast may be a lack of appetite or a lack of time to eat.

Not everyone will gain weight if they skip breakfast, but based on my theory, if some conditions are met and overlapped, it makes one more likely to gain weight. The biggest issue is simply a matter of "what to eat at lunch and dinner" and the interval between meals.

Eating only two meals a day makes the meal intervals longer. If you finish dinner at ten p.m., you will not eat for almost fourteen hours until the next day, at noon. Skipping breakfast makes you hungry, so in Japan, people tend to eat lunch with many carbohydrates (rice or noodles) and some meat. Some of them are satisfied with just being full, and their meal may lack fiber and other nutrients. 

hearty meal at lunch

However, since they have not eaten breakfast, all they have in their gut is that meal at lunch. If they don’t eat until eight or nine p.m. in that state, they are likely to induce intestinal starvation (a state where everything is digested) little by little, and their base weight may go up over time.

Some experts also point out that skipping breakfast and eating a carbohydrate-dense meal when hungry can cause blood glucose levels to spike, leading to high insulin secretion.

This may be true, but in any case, the combination of a "prolonged feeling of hunger" and an unbalanced diet leaning towards carbohydrates and with a lack of vegetables, is likely to make people fat, even if their caloric intake is not that much.

You can prevent intestinal starvation by doing the following: if you don't have time to eat in the morning, at least drink some milk, or eat a balanced lunch with a smaller amount of carbohydrates. And if you have to eat dinner late, eat something such as milk, chocolate or nuts, even around five p.m.

3. Conclusion

I think what has confused researchers over the years is “whether or not breakfast itself is directly associated with reduced risk of obesity and chronic disease? In other words, is there a causal link there?," and my thoughts, based on the intestinal starvation theory, are as follows:

(1)First, I think it is quite possible that people who usually eat breakfast have other healthy lifestyle habits.

For example, they may eat three times a day regularly, with a well-balanced diet that includes vegetables, dairy products, and protein, etc. throughout the day. They may also exercise religiously, get good quality sleep, and live in accordance with their circadian rhythms. 

On the other hand, those who tend to skip breakfast may have a nocturnal lifestyle and poor habits in terms of drinking, smoking, sleeping, and dietary balance.

In short, there might be some confounding factors associated with breakfast.

(2)However, as explained in section [2] above, eating a well-balanced breakfast early in the morning, will prevent intestinal starvation being induced by allowing undigested food in the gastrointestinal tract to remain around ten hours or so. Other health benefits of having undigested food such as fiber and fat in the gut, would include reducing blood sugar spikes and regulating appetite. 

On the other hand, an unbalanced breakfast skewed towards easily digestible carbohydrates, proteins, and processed foods, etc. can lead to weight gain, so I do not believe that "breakfast" itself has the effect of deterring weight gain. I’m certain that it is "which foods to combine" at breakfast that matter. (In this regard, intestinal starvation may also be a confounding factor.)

I personally think that if you don't want to eat breakfast, that's fine, but isn't it important to eat lunch and dinner in a balanced manner with a moderate amount of carbohydrates to maintain good health and reduce the risk of obesity?

(3)Also, in my theory, the problem of obesity implies a higher base weight, and 
 I believe just eating breakfast does not necessarily lower the base weight of a person who is already overweight. In other words, even if a randomized intervention to "eat or skip breakfast" were conducted in obese or overweight people as in a 2014 U.S. randomized controlled trial (RCT), it may be difficult to demonstrate the benefits of breakfast. But, this does not mean that breakfast itself is meaningless.


"When to Eat" Is Important, but It Should Be Paired With "What to Eat"


  1. What is chrono-nutrition?
  2. The importance of meal timing in the recent surge in obesity
  3. My thoughts

Chrono-nutrition has become increasingly important in recent years, and I have provided a brief background on this topic. At the end of this article, I would like to explain how my intestinal starvation theory relate to “when to eat.”

1. What is chrono-nutrition?

・Living organisms on the earth synchronize their activity to a 24-hour light and dark cycle generated by the rotation of the earth. This biological rhythm is called the circadian rhythm, which means “approximately one day.” Biological clocks are organisms’ natural timing devices, regulating the cycle of circadian rhythms. Recent studies have shown that clock genes such as BMAL1, CLOCK, PERs, and CRYs play central roles in the oscillation of the circadian rhythm[1].

・The circadian clock can be divided into two parts: the master clock, located in the suprachiasmatic nucleus (SCN) of the hypothalamus, which receives light cues, and the peripheral clocks that reside in organs and tissues throughout the body.

External stimuli (time cues) such as the light-dark cycle and the timing of food intake provide daily signals for entrainment (time-setting) of the master clock, and of metabolic rhythms in peripheral tissues, respectively[2].

Peripheral clocks are highly responsive to food intake in addition to the entrainment (synchronizing action) from the master clock.

・‘Chrono-nutrition’ is the study of the interaction between biological rhythms and nutrition, and the relationship between these factors and human health. Chrono-nutrition encompasses distribution of energy, frequency and regularity of meals, duration of the eating period, and the relative importance of these factors on metabolic health and risk of chronic disease. A growing body of evidence in human studies indicates that the timing of food intake throughout the day can have a significant impact on metabolic health and general well-being[3].

In Japan, it is generally believed that in addition to "what and how much" you eat, "when and how” you eat is considered important for maintaining metabolic health.

2. The importance of meal timing in the recent surge in obesity

(1)“What and when we eat” has changed dramatically in modern society.

Mistimed food intake in connection with the day/night cycle, such as skipping breakfast or eating later in the day, can disrupt circadian rhythms, which has been hypothesized to contribute to the development of obesity and associated cardiometabolic disorders[4].

irregular life rhythms

(2) There is a 3.5-year follow-up study showing that consuming a larger proportion of energy earlier in the day or at lunch, appeared to reduce the risk of weight gain[5].
On the other hand, previous observational studies in humans, have linked late eating with a higher risk of obesity and impaired dietary weight loss success that could not be explained by differences in reported caloric intake or physical activity [6].

(3) A short-term study (randomized controlled crossover trial) published in 2022 reported that late eating increases hunger, decreases metabolism, and alters molecular pathways involved in lipid metabolism[7], but it remains unproven whether it makes people obese in the long run.

shift workers

(4) Previous observational studies suggest that meal timing itself might influence body weight, independent of changes in energy intake and activity-related energy expenditure[8].

The mechanism behind the observed increased risk of obesity and weight gain in shift workers and in populations frequently eating late at night is likely to be multifaceted, and it cannot be explained by disrupted energy intake alone[9].

3. My thoughts

While “total daily caloric intake” is still being emphasized, I think it is a step forward that people are beginning to understand the importance of "when to eat,” even if it is the same caloric intake. And it has been my own experience that incorrect meal timing disrupts my biological rhythms, and I have no doubt that the discovery of clock genes will continue to increase the importance of this field. 

In fact, my intestinal starvation theory is related to "circadian rhythms" and "chrono-nutrition.” This is because the gastrointestinal tract gets active when food is consumed. I believe my theory also explains why a well-balanced breakfast and regular eating habits can prevent weight gain, and why late night eating and irregular lifestyles lead to an increased risk of obesity.

As quoted in section 2 above, some observational studies suggest that "mistimed food intake such as eating later in the day is linked to a higher risk of obesity that cannot be explained by disruption of caloric intake alone." But as I have explained throughout this blog, I don’t believe that obesity itself is directly related to the amount of calories consumed or burned. The typical pattern of obesity risk is represented by "no breakfast or late night meals” when the diet is unbalanced. 

What and when to eat

An unbalanced diet skewed toward easily digestible carbohydrates (white bread, noodles, mashed potatoes, etc.), protein, and processed foods is more likely to cause intestinal starvation when combined with irregular meal timing, and people can gain weight even if their caloric intake is not that high.

If obesity cannot be easily treated by returning to eating at regular times during the day, it means that one's base weight is higher.

[Related article]

Three (+one) Factors to Accelerate “Intestinal Starvation”

In other words, "when to eat" is important, but "what and how to eat" is important as well, and I believe they must always be considered as a set. If we focus only on caloric intake, we may forget the importance of traditional eating styles and dietary balance. (Note: Some Japanese nutritionists often stress how important the traditional Japanese diet is in addition to "what, when, and how you eat” for maintaining good health, and I totally agree with them on that point.)

In the category of "chrono-nutrition," I'll break it down into four articles on (1) breakfast, (2) late dinners, (3) frequency of eating, and (4) irregular meals, and explain in more detail how they relate to my intestinal starvation theory.

[Related article]

The Reason Why a Well-Balanced Breakfast Helps to Prevent Weight Gain



Calorie Calculation: Why the Atwater Coefficient Is Not Perfect


  1. What is the Atwater coefficient in the first place?
  2. Digestion is an entirely different process than burning food 
  3. Perspective from my intestinal starvation theory

Many experts still believe that “one calorie is one calorie.” If we apply this idea to weight control, we have to only be concerned with the number of calories in our diet, regardless of what different foods we eat or how we eat them. Of course, the human body is not that simple, and many researchers have warned against this kind of thinking.

In explaining this, I thought I should make a distinction between reactions that occur "inside" the body (after absorption) and those that occur “outside" the body (before absorption) (Note 1).
In this article, I would like to consider the Atwater coefficient, which is the basis for calorie labels on food products, as an issue that occurs outside the body.

gut, external of the body

As many gut microbiologists recognize, the digestive organs such as the stomach and intestines are "external" to the body (e.g. bad bacteria in the gut do not directly harm the body), which is perfectly consistent with what I have been explaining in this blog-the idea that the "absorption rate is important."

(Note 1: "Diet-induced heat production" actually occurs after absorption, but it is related to digestion, so I’d like to also use it here to explain it as an external response.)

1. What is the Atwater coefficient in the first place?

In the 1800’s, chemists developed a method to measure the amount of calories in food by burning food and measuring the temperature change from its surroundings. Burning food is chemically similar to the process by which our bodies break down food to obtain energy.

In the late 1880’s, Wilbur Atwater at Wesleyan University in Connecticut was studying what proportion of different foods humans could digest. 

Atwater set up an experiment using a “bomb calorimeter” to measure the caloric content in food. Foods with evaporated water were placed in a highly pressurised sealed container surrounded by a certain amount of water. The container was filled with pure oxygen to burn the food. The caloric content in the food was then calculated from the rise in temperature of the surrounding water. The amount of energy required to raise the temperature of one liter of water by one degree Celsius at sea level is defined as one kilo calorie[1].

However, digestion is a series of gentle chemical reactions over many hours, not like burning food in a bomb calorimeter. Therefore, we can only extract a certain percentage of calories in  food. So, it is said that Atwater fed human volunteers a variety of foods and measured the heat of combustion of the resulting fecal matter. By calculating the difference in heat of combustion between the food and the feces, he was able to approximate the number of calories absorbed by the volunteers. 

Atwater also took into account the fiber in food which we can’t digest(Note 2), and the nitrogen in our urine extracted from protein and excreted as urea. More than one-hundred-twenty years after this experiment, these "Atwater coefficient" are still the basis for caloric calculations for all foods[2].

(Note 2: It is now known that dietary fiber produces some energy through fermentation and breakdown by  the bacteria in the large intestine[3].)

Currently, the general Atwater coefficients of 4 kcal/g for carbohydrate and protein, 9 kcal/g for fat, and 7 kcal/g for alcohol are applied to all foods regardless of the type of food.
The use of specific Atwater coefficient is also allowed, which is different for each food group[4].

In Japan, since these coefficients were developed based on the average daily diet of Americans at that time, the coefficients for some major foods in Japan such as rice, soy products, animal products, etc.,were determined by studies conducted on Japanese subjects[5].

2. Digestion is an entirely different process than burning food 

We ingest food and then break down complex food molecules into simple structures such as glucose and amino acids by various digestive enzymes. After that, we get an energy source by absorbing them. Naturally, this is a completely different process compared to burning food in the laboratory. 

According to Professor Rob Dunn (North Carolina State University), every calorie count on food labels is based on estimates or approximations, and are not an accurate reflection.

Recent research has revealed that how many calories we get from a given food depends on a variety of factors, including which species we eat, how we cook food, which bacteria are in our gut, and how much energy we use to digest different foods (diet-induced heat production).[6]

(I)Digestibility varies even in vegetables

Even if it is same vegetable group, they vary in the firmness of their leaves and stems. The walls of plant cells in the stems and leaves of some species are much tougher than those of spinach, cucumbers, and other soft vegetables.

Also, even in the same plant, the durability of cell walls can differ. The older the leaves, the tougher the cell walls tend to be and the more difficult they are to digest.

Seeds such as corn and nuts, in particular, have such sturdy cell walls that they can hoard precious calories within them and pass through the body intact.

A study by Janet A. Novotny at the U.S. Department of Agriculture (2012) found that when people eat almonds, they take in just 129 kcal per serving, not the 170 kcal listed on the label. It is beginning to be proven that nuts such as peanuts, almonds, and walnuts have a more robust cellular structure than other foods with similar levels of energy sources, and that their cell walls limit digestion. It is possible that the Atwater coefficient overestimates the digestibility of nuts.[7]

(II)Calories vary depending on how we cook food

Prof. Dunn also mentions that the biggest problem with modern calorie labels is that they failed to account for how food is prepared and processed, which dramatically changes the amount of energy derived from  food.

We humans learned to cook raw food. We learned to process foods in different ways such as simmering, baking, frying, or even fermenting, to make them more palatable and tender. 
This should have dramatically increased the calories we extracted from food

Furthermore, some have pointed out that industrial food processing not only exposes food to high temperatures and pressures, but also softens food by adding air, to make it even easier to get more calories.

Corn, for instance, which is considered indigestible, is made into potage, and raw peanuts are roasted and processed into peanut butter. These processes must have dramatically increased the amount of energy available to the body. In other words, not all pork dishes are the same. The energy used for digestion and the absorption rate differ when roasting a chunk of pork versus making it into pâté.

(III)Energy required for digestion and immunity

Some research has shown that the energy required for digestion is not the same. This is called “diet-induced thermogenesis,” and it requires a great deal of energy to convert proteins into amino acids, fats into fatty acids, and carbohydrates into glucose. It is said that when proteins are broken down into amino acids, they require as much as five times more energy to digest as fats, because enzymes must unravel their tightly wound bonds[9].

According to Prof. Dunn, it also differs between whole grains and refined wheat. In a 2010 study, they found that people who ate 600-or 800-kcal portions of whole-wheat bread with sunflower seeds, kernels of grain, and cheddar cheese expended twice as much energy to digest that food as those who ate the same amount of white bread and "processed cheese products.” Consequently, those who ate whole-wheat substantially obtained ten percent fewer calories, they said[10].

raw meat

Many Japanese and Koreans traditionally love to eat raw fish or meat, if they’re fresh.

However, raw meat, for example, has been found to harbor many dangerous microbes, and our immune systems use energy to identify and deal with those pathogens[11].

It is possible that the same amount of cooked meat takes less energy to digest than steak tartare and has more usable calories .

(IV)Differences in digestive enzymes and intestinal bacteria

Most babies have lactase, an enzyme necessary to break down lactose sugar in milk, but it is said that most adults don’t produce this enzyme.

It has also been found that when starches such as rice and spaghetti are left to cool after being cooked, some of these starches crystallize into structures that digestive enzymes cannot easily break down.

What’s more, some microbes are present only in specific ethnic groups. Some Japanese, for example, have a microbe in their intestines which is suitable for breaking down seaweed. It has been found that these intestinal bacterium stole the seaweed-digesting genes from a marine bacterium that lingered in raw seaweed [12].

(V)There are variations for the method of calculation

The general Atwater coefficients were calculated based on the average daily diet of Americans at the time. Digestibility for carbohydrates, fats, and proteins were assumed to be 97, 95, and 92 percent respectively, and after adjusting a little for this, protein and carbohydrates were set at 4 kcal/g, fats at 9 kcal/g, and alcohol at 7 kcal/g[13]. Although metabolizable energy values vary slightly for proteins, depending on whether they are vegetable or animal protein, and for carbohydrates, depending on whether they are sugar or starch, the coefficients were derived by a system of an average.

On the other hand, specific Atwater coefficients are also allowed, which divides food into several groups and applies that thinking to the entire group.

It is said that the U.S. Food and Drug Administration (FDA) allows a total of five variations on the theme including these, and some point out that depending on the method chosen by the food company, there may be variation on the calorie labels[14]. When such uncertainties add up, the daily caloric intake could vary widely.

<Summary of this section>

Prof. Dunn mentions as follow:

(1) It is possible to modify the Atwater system for every food group, as in the almond example. However, this would require a challenge to reexamine the amount of nutrients retained in the feces for every food. 

(2) However, even if we completely revised calorie counts, they would never be accurate because how many calories we extract from food depends on a complex interaction between food, the human body, and its many microbes. In particular, the process of digestion is so complex that it is probably impossible to derive an accurate formula for calorie calculation that will suit everyone.

(3) Instead, we should think more carefully about the energy we get from food in the context of human biology. Processed foods are easily digested in the stomach and intestines, and thus provide a lot of energy for very little work. On the other hand, vegetables, nuts, and whole grains require more sweat to digest, offer far more vitamins and nutrients than processed foods, and keep our gut bacteria happy[15].

3. Perspective from my intestinal starvation theory

I believe that researchers and nutritionists at that time, including Atwater, were committed to ensuring that people could have an adequate amount of nutrition, and the calorie counting system they created had great merit. But I suspect it has been misperceived by some and is now causing problems with those who are overweight.

The reason why the problem of obesity hasn’t been solved is that many people are so focused on the "number of calories ingested or burned" that they are likely to forget what is most important.

Let's say you eat, as in the example in the section 2-[III], 400 kcal of a meal: whole-wheat bread, nuts, and grilled chicken. Assuming that, after taking into account the energy required for digestion, you obtained ten percent fewer calories (360 kcal),
the argument that "wouldn't it be the same if you ate 360 kcal worth of white bread and chicken terrine?" is complete nonsense.

Fibers from whole-wheat bread and nuts tend to remain undigested in our intestines, which means there is a message to the body of "there is still food," but the combination of white bread and easily digestible protein, etc. is quickly digested, and if the "three factors + one" of my theory are met, the intestinal starvation message saying "there’s no food" would be sent to the brain through the small intestine.

In other words, you can gain weight despite a reduction in total daily caloric intake.

Similarly, conventional advice and actions often taken to reduce daily caloric intake, such as skipping breakfast or eating a light lunch such as a hamburger or a cup of noodles, can also cause intestinal starvation and lead to increased base weight.

I have been explaining throughout this blog that the fundamental difference between obese people and thin people can be explained by the difference in base weight value, and that a higher base weight means "higher absorption ability," which is induced by intestinal starvation.
And since one of the key factors causing intestinal starvation is how fast you digest food, both digestion and absorption ability are extremely important in my theory.

Nevertheless, if we believe that only numbers based on averages of subjects are all we have, we ignore them. As Prof. Dunn mentions, I don’t believe that the complexity of digestion and absorption for a diverse population can be described by a system using an average.

(Please read the following article for other issues in "calorie counting.")

There is No Meaning in Simply Calculating Calories You Consume


The Atwater coefficients is a measure of how much energy we can obtain from food, but I think it is inadequate to address the problem of obesity. Even if we revised the Atwater coefficients more accurately by taking into account energy required for digestion and food composition, the obesity problem will not be solved if we judge things only by the number of calories.

One idea that has been suggested is to introduce a "traffic-light" system on food labels, alerting consumers to foods that are highly processed (red dots), lightly processed (green dots) or in-between (yellow dots) [16], and I agree with this idea. It is also possible to combine satiety, the number of chews, and the indigestibility of food into this traffic-light system.

classic food

What we need now, I believe, is to take a little away from the apparent accuracy of "calorie counting," which seems more scientific, and rethink our traditional diets and eating habits.

This overlaps with what Prof. Dunn has also pointed out, but eating traditional fibrous vegetable dishes, unprocessed meat or fish, dairy products, fermented foods, and whole grain breads, etc., cannot be judged by caloric benefits alone.

Those foods contain far more vitamins and minerals than processed foods, and their fiber content keeps our gut bacteria in good condition, gives us moderate satiety, prevents rapid absorption of glucose, and provides many other health benefits. Depending on how you eat them, it should be possible to lose weight without worrying about caloric intake.

[1][2](Giles Yeo, "Calories on food packets are wrong–it's time to change that",2021) 
[3](Japan Food Research Laboratories, “The Energy in Food(食品のエネルギーについて)”, 2003) 
[4](The Nutrition Coordinating Center (NCC),"Primary Energy Sources")
[5](Kazuko Takada(高田和子), “Absorption and Utilization of Energy in the Body(摂取したエネルギーの体内での吸収と利用)”, Physical Fitness Science(体力科学) , 2007, P56, 287-290)
[6][7][8][9][10][11][12][15](Rob Dunn, “Science Reveals Why Calorie Counts Are All Wrong”, 2013)
[13](Kazuko Takada, “Absorption and Utilization of Energy in the Body”, Physical Fitness Science ,2007, P.56, 288)
[14](Cynthia Graber, Nicola Twilley, “Why the calorie is broken”, BBC future, 2016
[16](Richard Wrangham, Rachel Carmody, Harvard University,”Why Most Calorie Counts Are Wrong”, 2015)


The Atkins Diet: What Were the Long-Term Effects of Weight Loss?


  1. What is the Atkins diet?
  2. Comparative study of various diets in weight loss
  3. What were the long-term results of the Atkins diet?
  4. Why was obesity rare among rice-eating Asians?
  5. Is the Atkins also ineffective for weight loss?
    <The bottom line>

1. What is the Atkins diet?

The Atkins diet is a type of low-carbohydrate diet proposed by cardiologist Robert Atkins that restricts the amount of carbohydrates for energy and instead uses "fat" as an energy source. It is characterized by limiting carbohydrates to twenty to twenty-five grams per day for the first two weeks and then gradually increasing.

According to Dr. Fung, the author of “The Obesity Code,” Dr. Atkins weighed nearly one-hundred kilograms in 1963, and when he began working as a cardiologist in New York City, he needed to lose weight. 

However, he couldn’t lose weight successfully on a conventional calorie-restricted diet, so he tried the low-carb diet based on the medical literature, which worked well as advertised, and he recommended it to his patients. 

In 1972, he published "Dr. Atkins' Diet Revolution," which quickly became a bestseller.

At the time, it was said that the American Medical Association still considered high fat in the diet to be a cause of heart disease and stroke, and the "low-carb diet," which allowed people to eat as much meat and fat as they wanted, was not accepted.

Despite this, the low-carb diet’s popularity, rekindled in the 1990’s, led to a trend in the Atkins diet. In 2004, twenty-six million Americans said they were on some kind of low-carb diet .

New studies started appearing around 2005, comparing the Atkins diet to other diets that were once considered the standard, and what were the results?[1]

Let's take a look. I would like to express my thoughts on this at the end of this article

2. Comparative study of various diets in weight loss

"In 2007, the Journal of the American Medical Association published a more detailed study: Four different popular weight plans were compared in a head-to-head trial.

One clear winner emerged-the Atkins diet. The other three diets (Ornish, which has very low fat; the Zone, which balances protein, carbohydrates and fat in a 30:40:20 ratio; and a standard low-fat diet) were fairly similar with regard to weight loss. 

nurse and patient

However, in comparing the Atkins to the Ornish, it became clear that not only was weight loss better, but so was the entire metabolic profile. Blood pressure, cholesterol and blood sugars all improved to a greater extent on Dr. Atkins's diet. 

In 2008, the DIRECT (Dietary Intervention Randomized Controlled Trial) study reaffirmed once again the superior short-term weight reduction of the Atkins diet. Done in Israel, it compared the Mediterranean, the low-fat and the Atkins diets. 

While the Mediterranean diet held its own against the powerful, fat-reducing Atkins diet, the low-fat AHA standard was left choking in the dust–sad, tired and unloved, except by academic physicians.[2]" 

3. What were the long-term results of the Atkins diet?

"Longer-term studies of the Atkins diet failed to confirm the much hoped-for benefits.
Dr. Gary Foster from Temple University published two-year results showing that both the low-fat and the Atkins groups had lost but then regained weight at virtually the same rate. (*snip*) 

A systematic review of all the dietary trials showed that much of the benefits of a low-carbohydrate approach evaporated after one year.


Greater compliance was supposed to be one of the main benefits of the Atkins approach, since there was no need for calorie counting.

However, following the severe food restrictions of Atkins proved no easier for dieters than conventional calorie counting.

Compliance was equally low in both groups, with upwards of 40 percent abandoning the diet within one year.

In hindsight, this outcome was somewhat predictable. The Atkins diet severely restricted highly indulgent foods such as cakes, cookies, ice cream and other desserts. 

These foods are clearly fattening, no matter what diet you believe in. We continue to eat them simply because they are indulgent. (*snip*)The Atkins diet does not allow for this simple fact, and that doomed it to failure.

The first-hand experience of many people confirmed that the Atkins diet was not a lasting one. Millions of people abandoned the Atkins approach, and the New Diet Revolution faded into just another dietary fad. (The company Dr. Atkins founded in 1989 went bankrupt.)

But why? What happened?
One of the founding principles of the low-carbohydrate approach is that dietary carbohydrates increase blood sugars the most. High blood sugars lead to high insulin. High insulin is the key driver of obesity. Those facts seem reasonable enough. What was wrong?[3]"

4. Why was obesity rare among rice-eating Asians?

Experts who advocate low-carbohydrate diets seem to think that carbohydrates cause weight gain because they eventually stimulate insulin secretion.

However, Dr. Fung mentioned that the carbohydrate-insulin hypothesis is incomplete. Various problems are cited, but he raised the "paradox of the Asian rice eater" and the "diet of Kitava Island, in Papua New Guinea" as notable examples.  

Most Asians have been eating a diet based on refined rice as their staple food for at least the last five decades; a study conducted in the late 1990’s found that carbohydrate intake in China and Japan was similar to or rather, higher than in the U.K. and the U.S. 

rice-eating Asians

Nevertheless, until recently, obesity was not a significant problem in both countries.

Also, according to a study conducted by Dr. Staffan Lindeberg in 1989 on the diet of the Kitava islanders,  even though they were getting sixty-nine percent of their calories from carbohydrates such as yams, sweet potatoes and cassava, etc., their insulin levels were low and few people were obese [4].

Since Dr. Fung just mentioned the paradox of the Asian rice eater, I would like to mention this.

I am Japanese and was born in 1970, and I think that I should know how our diet has changed in the last five decades, and as a result, how obesity has increased in our society. 
(This is explained in more detail in the following blog.)

[Related article]  Why Does the Body Perceive That It Is More Starved than in the Past?

In short, I believe that carbohydrates are a contributing cause, but not the quantity itself.
Japan was basically an agrarian society, and rice cultivation has always been important. Until at least 40-50 years ago, I believe most Japanese people had eaten a lot of rice as it is called the staple food, but at the same time, they also ate a lot of fibrous vegetable dishes using roots or stems of plants, fermented soybean product called “natto,” and fish and meat dishes. Rice cakes called “mochi” and Japanese sweets as well.

At least in my family, my father was strict about family members eating meals three times a day at a regular time, every day.

I think the recent increase in the obesity rate in Japan can be explained due to a combination of many factors, including easily digestible carbohydrates such as bread and noodles, unbalanced diets with few vegetables, eating out, instant foods, and irregular life rhythms such as skipping breakfast or late dinners. 

What I have seen in my experience is that many young women who go on a diet and then come off, some of them further increase their maximum weight.

irregular life rhythms

(Irregular lifestyle)

I believe that the "three factors plus one" of my intestinal starvation theory can explain how the various factors intertwine, and how weight gain occurs. It's not just the amount of carbs eaten that matter.

5. Is the Atkins also ineffective for weight loss?

The "Do calories make people fat, or carbs?" concept is said to be a debate that has been going on since the 1800’s [5], and I think both are true in some ways, but neither is perfect.

If you reduce the amount of any energy source beyond what your body needs, it’s obvious that you will lose weight in the short term. However, if you go back to your original diet, in the long run, you will also regain the weight you had lost, as various studies have confirmed, and as most people who have been on a diet have probably realized.

The reason for this is that the human body, I believe, basically works to maintain the status quo. I introduced "base weight" to describe the body weight based on that. So, the point is that in order to avoid rebounding, you must lower your base weight itself. 

(For more information on how to do this, please see the following article.)

[Related article]  There Are Two Steps to Lose Weight the Right Way

In terms of this rebound in the Atkins diet in section three, I don't think it necessarily means that low-carb diets, including Atkins, are ineffective. I’m positive that it’s the one of the correct ways to lose weight.

However, if we focus too much on blood sugar and insulin levels, we lose sight of another important point.

What I mean is that, the point of a low-carb diet, I believe, is not only the reduced carbohydrate amount, but also "how we increase the amount of other indigestible foods including meat, fat, fibrous vegetables, dairy products, etc." By sending plenty of indigestible foods to the gastrointestinal tract, we should feel less hunger and, in turn, the absorption rate should decrease. In particular, fats and oils in the diet should not be reduced, but rather should be consumed at every meal and even when having snacks.

From that point of view, I think that dieticians did not need to ban sweets such as chocolate, candy, ice cream, etc. so strictly. What is important is to be able to have them occasionally and not be too hard on yourself.


[1] Dr. Jason Fung, The Obesity Code, 2016, Pages 96-99.
[2][3] Pages 100-103.
[4] Pages 103-105.
[5] Gary Taubes, Why We Get Fat, 2011, Pages 148-162.

The bottom line

(1) In the early 2000’s, the Atkins diet became a huge trend in the U.S., inspired by the low-carb diet that was rekindled in the 1990’s. In the short term, the Atkins method not only helped people lose weight, but it also significantly improved blood pressure, cholesterol, and blood glucose levels.

(2) However, in long-term studies, the subjects rebounded, as seen with low-fat diets. After one year from the end of the study, all the benefits of Atkins diets were gone.

Dr. Fung considered the "carbohydrate-insulin hypothesis" an incomplete theory. Carbohydrate intake itself was not the problem.

(3) My thoughts. If there is no change in your base weight, rebound can occur if you eat as you used to. In order to lose weight correctly, your base weight itself needs to be lowered.

(4) The point of a low-carbohydrate diet is not just  the amount of insulin secreted. I believe that it’s rather important
to "take in more indigestible foods other than carbohydrates, and not feel hungry." 



Why Are Sumo Wrestlers So Fat?; Six Reasons They’ve Adapted to the Gut Starvation Mechanism


  1. The same mechanism as people who rebound after dieting
  2. The six reasons that I believe it is a starvation mechanism
    The bottom line


Have you ever seen a sumo wrestler right in front of you? When I was working as a waiter at a hotel several years ago, there was a pep rally for sumo wrestlers, and I was able to see them up close.

Also, at the 2017 Osaka tournament in Japan, I observed the morning practice of a team and was allowed to sample their breakfast called "chanko."

meal called chanko

I had a sample of "chanko."

sumo wrestler

I got the impression that they are big-boned, with steel-like muscles, and a lot of body fat on top of that.  

Their average body fat percentage is said to be around thirty percent or more, but there are some wrestlers in the twenty percent range, not that different from the average person. They are like a mass of muscles. 

It is generally believed in Japan that wrestlers will gain weight because they eat a lot and sleep well including taking naps, but I can explain that they have successfully adopted the mechanism of intestinal starvation.

1. The same mechanism as people who rebound after dieting

In Japan, the image of sumo wrestlers in particular may lead to the image that "eating more makes you fat," but I would like to explain that this is the same mechanism as "those who end up rebounding after dieting and gain more weight than before" or "those who gradually gain weight by skipping breakfast or having a late dinner.”

First of all, I'm going to illustrate how both of them gain weight in the figure below. 

■The concept of a person who gains more weight than before after dieting


(1) You will lose a little weight through caloric restriction or exercising, etc.

(2) When you eat less (especially with an unbalanced diet), and you feel hungry for an extended period of time, you tend to starve your gut, and your base weight may go up without you realizing it. 

(3) Later, when you start eating as you did before dieting, your weight will be higher than before.

■The concept of sumo wrestlers gaining weight


(1)First, by their traditional unique diet and hard practice, intestinal starvation can be induced. Their base weight goes up. 

(2)Then, they eat a lot and thire actual weight increases (weight gain).

If you are a dieter, there is a time lag, but in the case of wrestlers, they eat good amounts of food every day, so it happens almost simultaneously.

Although they appear to eat a lot and are gaining weight, if intestinal starvation is not induced, their weight should not increase as much as expected.

2. The six reasons that I believe it is a starvation mechanism

When you see big eaters in a food eating competition, some may ask, "Why don't they get fat even though they eat so much?” But, from my theory, it is not at all surprising.

It’s not that they have a special "non-fattening constitution," but that anyone who eats like that from morning to night is less likely to gain weight (although I wonder why they can eat so much food at once).

Please understand that the way of eating of a sumo wrestler is a far cry from that of an eating competitor.

■An explanation of why the way of eating and exercising of sumo wrestlers can easily induce intestinal starvation. (1) - (6) 

(1)A wrestler must weigh at least sixty-seven kilograms to be admitted. People who are overweight or muscular from the beginning tend to have stronger stomachs, and are thought to have a relatively high digestive rate. Such people are more likely to induce gut starvation than thin people.

a chanko dish

(2) The basic diet for sumo wrestlers is called "chanko," which consists of easily digestible proteins such as chicken, fish, tofu, etc., and vegetables, slowly simmered in soy sauce. It is relatively low in fat and easy to digest. 

(3) Sumo wrestlers generally eat a good amount of rice. By eating a lot of rice and soup, the stomach expands (the balloon effect), which leads to creating the dilution effect and push-out effect of food in the stomach.

[Related article]

The Dilution Effect/ Pushing Out Effect of Carbohydrates

(4)They traditionally eat two meals a day: the first meal is around eleven a.m. after morning practice, and dinner is around six p.m.
Since they practice from the early morning without breakfast, if dinner is finished at seven p.m., it means that they do not eat for about fifteen to sixteen hours until the next meal. It make sense to do intense morning training on an empty stomach to gain weight.

Of course, there are some wrestlers who try to eat snacks or supplements late at night in order to take in more calories, but my idea is that it makes easier to gain weight when they don't eat.

morning practice of sumo wrestler

(5)Strength training is a force for gaining strength, and it ultimately works in the direction of weight gain. Eating two meals a day and exercising intensely will make sumo wrestlers gain more weight.

(6)Most of the food in the pot is eaten first by the top-ranked wrestlers. The lower-ranked wrestlers eat next, and lastly the new trainees. 

The last people have to eat a big ball of rice and leftovers, which consists of only a little meat and most of the soup.
it is said that this kind of meal tends to make sumo wrestlers gain more weight.

The bottom line

(1)Sumo wrestlers are famous for being big and fat, but they do not gain weight because their daily caloric intake exceeds their daily caloric expenditure.
Their traditional diet and exercise makes sense in terms of weight gain in that it facilitates the creation of intestinal starvation.

(2)Intestinal starvation is more likely to be induced when a person who has a big body from the start eats relatively easily digestible foods with lots of carbohydrates (rice) and two meals a day.

(3)The mechanism by which wrestlers gain weight is the same as that of "people who diet and gain more weight than before due to the rebound effect.”
In the case of sumo wrestlers, since they eat a lot every day, this happens almost simultaneously, and they appear to eat a lot and gain weight.