Many people say that eating too much fat or oil makes you fat, since fat has more than twice as many calories as carbohydrates or proteins per gram. But some research shows that some people can lose weight even though they increase fat or oil in diets.
Which is true?

To make a long story short, I think both are correct. As I have mentioned so many times before in this article, there are two meanings to the phrase “gain weight,” and based on my theory, I can say that eating fat has three sides to it.

He concluded :

• Low-fat diets are ineffective for weight loss.
  
• Dietary fat intakes are not strongly linked to body weight, and some evidence links increased fat intake with lower body weight.
  
• Insulin is the key driver of fat accumulation in the body. Dietary fat does not stimulate insulin secretion directly, and therefore has limited fattening potential.”
  
• Obviously, eating nothing but fat is not to be advised, but some study open up the possibility that a fat-rich diet may actually assist our weight-loss efforts.[1]
     

I’m not a specialist or researcher. Therefore, I’d like to avoid mentioning how insulin or other hormones work in the bloodstream. But I believe I can explain why low-fat diets are ineffective for weight loss vs fat-rich diets that may help our weight-loss efforts, based on my theory.
I will explain in the next section. 

Based on my experience, I believe that people who say they gained weight by consuming fat or those who say they lost weight, are both true. However, each only highlights one aspect of the properties of fat. Focusing solely on 'calories' can obscure these different aspects. 

I can say that three different effects can be expected depending on the the subject of intake (who) and/or the way of intake (such as the amount and frequency).

People who have a higher digestive ability for dietary fat, especially those who are dedicated to dieting to keep their weight low or those aiming to shed excess fat to achieve a muscular physique, will get especially fat in a few days if they consume high-calorie foods like sweets, cakes, and deep-fried foods. The fattening effect seems especially acute when eaten with a good amount of carbohydrates or when having only two meals a day. 

　　
With these images, many people reject a revolutionary suggestion of taking fat/oil in order to get slim, and that’s what makes this theory hard to accept.
              

In any case, fat digestion is more complex than other nutrients and tends to inhibit intestinal starvation.

For example, if a thin person wants to gain weight, eating a lot of fat/oil at meals will hinder gaining weight. Have you ever wondered, “why was he/she not getting fat despite the fact that they were eating high calorie foods, such as cakes, cookies, deep-fried foods, or fatty foods?”

In fact, a low-fat, easily digestible diet is more likely to make you gain weight in terms of increasing your set-point weight itself.
       

As Dr. Briffa whom I’ve mentioned above said, I also believe that "in a low-carb diet, increased fat intake is linked to lower body weight” is in a way correct, as though this doesn’t apply to everyone. 

It is generally believed that the reason is that fat, unlike carbohydrates, does not stimulate insulin secretion, but I will avoid mentioning that for now. Other than that, here is what I would like to add and explain based on my theory.

The time it takes for fat to be completely digested can be six to eight hours, depending on the amount of food eaten and how we combine different foods. Therefore, by consuming fat/oil every four to five hours, undigested food will remain in the stomach and the large part of the intestines for most of the day, which lead to decreased feeling of hunger and, in turn, reduced absorption ability (rate and amount).

As seen in low-carb diets, by decreasing carbohydrate intake to an extent and increasing the intake of fats, proteins, nuts, and vegetables, etc., dense nutrients are delivered to the intestines, which takes even longer to digest. If you continue with this eating habit, I believe it maximizes the dieting effect. 

[Related article]
The Dilution Effect/ Pushing Out Effect of Carbohydrates
      

(1) Just because fat has nine kilo calories per gram, does not mean that dietary fat always makes people fat.

For those who have a higher digestive ability for dietary fat, especially those who normally keep their weight lower to lose weight, eating fatty food can be a cause of weight gain, but depending on the subject of intake (who) and/or how you eat it (how much, how often), fat can have a deterrent effect to further weight gain or diet effect.

(2)Fat takes longer to digest than other nutrients, so if you frequently eat fat, undigested food tends to remain in the intestines. This makes intestinal starvation less likely to occur, which tends to deter further weight gain in the sense that one’s set-point weight doesn’t change.

(3)A diet low in carbohydrates but high in protein and fat may have a dieting effect. It is generally believed that the main reason is that fat, unlike carbohydrates, does not stimulate insulin secretion.

My theory, I would add, is that ingesting fats every four to five hours will leave undigested food in the wide range of intestines, which will lead to reducing feeling of hunger and, in turn, decreased absorption ability. Continuation of this condition could have a weight-loss effect.
         

It is said that exercising and food restriction is necessary for losing weight. However, we rarely meet those who succeeded in dieting using such a method.

Japanese wrestler Bull Nakano (below) has repeatedly dieted and rebounded, but after having knee problems, it was imperative that she lose weight, so she had a gastrectomy to remove part of her stomach.
She said that “cutting the amount of foods and exercising didn’t make her thinner.”

In this article, I would like to introduce how conventional calorie-based diets are ineffective, based on two books: "Escape the Diet Trap" and "Why Do We Get Fat.”
Please note that most of these are quotations.

"Limiting the studies to those where individuals were monitored for at least two years after the start of their efforts to lose weight allows us to assess the long-term success of these approaches. Many of us will know what it is to get a short-term win from eating less and exercising more but it's the long game we're interested in here.

 "Prescribing low-calorie diets for obese and overweight patients, according to a 2007 review from Tufts University, leads, at best, to “modest weight losses” that are “transient” – that is, temporary. Typically, nine or ten pounds are lost in the first six months. After a year, much of what was lost has been regained.

Together they enrolled more than eight hundred overweight and obese subjects and then randomly assigned them to eat one of four diets. These diets were marginally different in nutrient composition (proportions of protein, fat, and carbohydrates), but all were substantially the same in that the subjects were supposed to undereat by 750 calories a day, a significant amount.

I’d like to talk about how meaningless it is to calculate the accurate caloric intake for the day, and apply it to weight control to lose weight.

It is said that the caloric values of food that we use to calculate caloric intake are based on the Atwater system(the coefficient of 4 kcal/g for protein and carbohydrate, 9 kcal/g for fat, and 7 kcal/g for alcohol), but various problems have been pointed out regarding the accuracy of these factors.

[Related article]
  Calorie Calculation: Why the Atwater Coefficient Is Not Perfect

I believe that one of the problems is that digestibility and absorption rates are based on a system of  averages, and I would like to explain that. (This article focuses on how people absorb energy differently, and I won’t mention the process after absorption such as the metabolic process or the differences in hormone secretion, etc.)
   

The Atwater coefficient is based on the average energy value that we can absorb from food, but it seems like it has not been investigated how the absorption rate varies depending on what time of day you eat, how often you eat, or how you combine other foods in a meal.

Also, since this factor is calculated from an average of the subjects, it assumes that everyone has the same digestion and absorption ability[2].

Because I was very thin, my digestibility was poor, and I often had gastrointestinal problems. I felt like I was a guinea pig. If I ate too much fatty or fibrous food, my stomach would be upset even after several hours. And if I forced myself to eat my next meal in that state, I felt that I lost even more weight.

In the Atwater coefficient, fat is said to have a caloric value of 9 kcal/g because its physical combustion heat is 9.4 kilo calories and its digestibility coefficient is set at 95% [3], but for people who have trouble digesting it, including myself, that number is meaningless. 

In the following, I will explain how our absorption rate varies for an individual based on my experience.
      

To be more specific, even if you reduce the 700 kcal lunch to 400 kcal and eat nothing until dinner, there is still breakfast in your gut, and your intestines wil be working really hard to take in nutrients out of what is left. 

Even when the body uses stored energy sources, not all of them lead to a reduction in body fat because some energy sources are used first. In addition, I believe, the more hunger continues, the higher the absorption ability after dinner is, so the body fat should not be reduced as calculated even if the reduced 300 kcal of energy each day is totaled, for instance, for a two-week period.
(The body is said to be in equilibrium with less weight loss than expected, since the basal metabolism also decreases along with weight loss.)
    

On the contrary, if you continue to force yourself to eat every three to four hours even though you are not feeling hungry, your absorption rate will decrease, relatively speaking. (Of course, it differs from person to person.)

Consider this for instance, after we eat food, it digests for a few hours, and finally, when it is starting to be  absorbed, another food comes into the stomach. So, the body will perceive that, “here comes some more food... we can simply take nutrition from that.”

In the previous example of blood glucose, if you eat ice cream two hours before a meal, the rise in blood glucose levels at the meal should slow down. 

How we combine different foods in a meal also makes a difference in hunger and the absorption rate.

As an example, consider a 400 kcal of breakfast (a slice of toast, ham, fried egg). Even if the caloric intake increases, I think adding a burdock salad, cheese, beans, sautéed mushrooms, etc., to breakfast will suppress hunger at lunch and help reduce the rise in blood glucose levels.

I believe it’s partly because that by constantly eating indigestible foods that contain a lot of fiber, or foods that take a long time to digest, undigested food will remain in the gut which suppresses hunger and decreases the absorption rate. It might also be possible that the fiber itself slightly hinders absorption.

How we combine macronutrients such as carbohydrates, proteins, and fats in a meal also makes a difference.

Based on calorie theory, we are taught by nutritionists, doctors, and TV programs, that "if you eat a lot of fat, you will get fat" because fat has nine kilo calories of energy per gram.

However, studies have repeatedly shown until the 1970's that diets that reduced carbohydrates and increased protein and fat as much as one wanted, as seen in carbohydrate-restricted diets, had caused weight loss in subjects, even though their daily caloric intake increased[5].

For the same reason as the indigestible fibrous foods in section (2) above, a diet with less easily digestible refined carbohydrates and relatively more indigestible fats and meats (especially unprocessed slabs or chunks), etc. will reduce hunger, decrease absorption, and help you lose weight because the undigested food will remain in the gut for longer periods of time. More benefits should be obtained by incorporating fat into each meal or even between meals as snacks.

Of course, this effect may be less pronounced for people or ethnic groups that can digest fat and protein quickly, but for those who cannot digest fat quickly, including myself, consuming more fat will not cause weight gain.

I believe this may be related to data showing that in the U.S., the rates of obesity defined as having a body mass index of thirty or more increased dramatically from 1977 as a result of the promotion of low-fat diets (high carbohydrate) between 1976 and 1996 [7].

[Related article] Eating Fat/Oil Is a Deterrent to Gaining Weight

The explanation in section 2 above is how the absorption rate changes in an individual, but as I’ve mentioned throughout this blog, the fundamental difference between overweight and thin people can be explained by the difference in 'set-point' for body weight.

And my theory is that this higher set-point weight means a state of "absolutely higher absorption" than a person of average weight, and since I believe that all nutrients are increased, the increase in weight is related not only to body fat, but also to increased muscle mass.

At this point, I can't point out the discrepancy in the Atwater coefficient to explain how one’s set-point for body weight changes, but I would certainly like to prove that people can gain weight due to intestinal starvation.
    

<References>
[1] Jason Fung. The Obesity Code. Greystone Books, 2016, Page 67.

[2] Rob Dunn,"Science Reveals Why Calorie Counts Are All Wrong",2013.
[3] Japan Food Research Laboratories, 「The Energy Content of Food (食品のエネルギーについて)」,2003.
[4] Rob Dunn,"Science Reveals Why Calorie Counts Are All Wrong",2013.
[5] Gary Taubes. Why We Get Fat. New York: Anchor Books, 2011, P164-175.

[6] Jason Fung, The Obesity Code, P.177-179.
[7] Jason Fung, The Obesity Code, P.54-5.

(1)While it makes sense to calculate daily caloric intake as an average guide in the case of mass food preparation (school lunches, elderly homes, etc.), it does not make much sense to apply it for dieting for each individual. There are many other problems in the concept of being overweight.

      
(2)The Atwater coefficient is based on the average subject’s ability to digest food , but the process of human digestion and absorption is complex and cannot be described by a system that consist of an average value.

    
(3)In my opinion, one’s absorption rate varies with how hungry you feel and the intensity of exercise you do. Moreover, what time of the day you eat, meal intervals, and which different foods are combined in a meal also affect the outcome.

    
(4)I believe that the fundamental cause of being overweight can be explained by the higher set-point weight, and reducing caloric intake may result in temporary weight loss, but in the long run, it will not be effective.
   

This time, I would like to explain the relationship between the mind and the mechanism of gaining weight.

Some people who are overweight may start dieting with the thought, " I'm definitely going to lose a few kilos this year.” According to conventional calorie theory, the strategy to do so is to "eat less and/or exercise more.” Many of them first try to avoid high-calorie foods such as oily foods, fried foods, and sweets. Also, they try to skip meals or eat just a little in order to take in fewer calories. In addition to this, some may start jogging or go to a fitness club.

On the other hand, people who are thin tend to think, “I want to gain a little more weight” or “If I skip a meal, I will get thinner.” So, they try not to skip meals and try to eat foods with more calories even though they can’t eat a lot in one sitting.

Obese people might get thinner for a while through eating less and exercising more. However, it’s a temporary thing, and over the long haul, it’s not that effective.

With the long periods of hunger caused by restricting meals as in a diet, the intestines improve their absorption ability in order to get the maximum absorption out of a small amount of food. If they don’t eat a balanced diet and their diet leans toward some digestible carbohydrates and protein, the intestinal starvation mechanism may occur. As a result, the 'set-poit' for body weight may go up unknowingly and they’ll find themselves gaining more weight than before. (The rebound effect).

In contrast, when thin people skip meals, they soon start to get thinner in the face and get tired easily since they don’t have stamina. So, they believe they have to eat something even though they don’t feel so hungry. This is a natural way of thinking for creatures to live... 

And that’s why many thin people tend to eat three meals a day and also eat high-calorie foods even if they don’t eat a lot. Also, some people snack between meals without hesitation. There are specialists and some websites that recommend they eat more calories to gain weight. 

However, this makes intestinal starvation less likely to occur because undigested food remains in the intestines throughout the day, and the function of the body to store energy will not work. In short, the ‘set-point’ for body weight has not changed. Regardless of the calories they consume, they never gain weight, so they end up saying, “It’s the way I’m made.” 

　　
Generally, genetics are used as an excuse to explain the difference between people who eat a lot but never gain weight over the course of their life, and those who tend to gain weight even though they are dieting. Of course, genetics cannot be completely ignored, but since they are theoretically doing the opposite of what they need to do, it is not surprising that both do not work.

To begin with, we need to change the stereotype that "overeating and less exercise” are the causes of weight gain, to stop the obesity epidemic and discover something new.
　　　

I’ve stated before that what increases your set-point weight is the hunger mechanism (intestinal starvation) and here, I want to talk about three(+one) factors that accelerate intestinal starvation.
【Related article】→My Definition of “Intestinal Starvation”
    

When there is only one of the situations from above, the intestinal starvation mechanism hardly occurs. However, when there are three and the +one factor which I will discuss later, the mechanism for intestinal starvation happens more often.

Some say they gained weight from eating too many carbohydrates, but others won’t seem to gain weight even if they eat a lot of carbs.
Some say they gained weight by eating junk foods late at night, but others don't gain at all, even if they eat in the same way.

These differences exist since intestinal starvation is decided by the composition of various factors.

Meals with mainly refined carbohydrates (starch) and some good protein (a small amount is enough) and less fiber intake from vegetables, make people fat most easily. It seems with less fat in the diet, intestinal starvation is more likely to be induced. It’s because dietary fat slows digestion.

*Eating speed, how many times you chew your food, or hydration during the meal, are also related to the above.
 

Eating late at night won’t automatically make you fat. If you have to eat a late dinner, you can snack (milk, chocolates, or  sandwiches, etc.) between meals in order to prevent intestinal starvation.
  　　

If there are genetic factors, the difference of digestive ability will be the first thing I will bring up as the factors. And it may vary between races as well as between families. (Of course, it may change after birth.)

I stated that an important factor other than the above three factors is “+one,” but this can be explained by a “continuity,” which is whether you had an unbalanced diet (or a light meal) for your previous meal and the meals before that.

The reason for this is that the intestines are as long as seven to eight meters, so it takes the food more than ten hours to pass through.

Intestinal starvation is determined by the entire intestinal tract (or it might be the small intestine only), so the previous meal or the meals before that also affect it.