Starve, don't starve – 2

YuriDeigin, Geektimes

Quite unexpectedly, my completely toothless post about monkeys provoked a serious debate. They turned out to be quite interesting and informative, even despite a couple of comments in the spirit of "THE AUTHOR IS LYING!!". In the end, it turned out that my only "sin" is that I dared to call calorie restriction "starvation".

Well, I am really guilty of this: I consider calorie restriction to be a kind of fasting, but at the same time in the original article I repeatedly mention that in experiments on macaques, it was the 30% calorie restriction that was studied. However, the "real", from the point of view of purists, fasting is also described there: we are talking about the study of the effect on prolonging life from feeding every other day (every other day feeding) on rats, so there can be no question of any bias on my part.

In my interpretation of the term "starvation" I am far from alone. Dictionaries define it exactly the same way:

Fasting: a condition of the body that develops with the complete absence or lack of food, its incomplete composition, as well as with disorders of digestion and assimilation of nutrients (Medical Encyclopedia).

TO STARVE – TO STARVE, ay, ay; imperfect. 1. Experiencing hunger (in 2 and 3 digits). Assistance to the hungry (s.). 2. Abstain from eating or sharply limit yourself in eating. G. on fasting days. | entity. fasting, I, cf. Medical G. (Ozhegov's Explanatory Dictionary).
Starve – ness. neperekh. 1. To experience hunger 2., 3. for a long time; to eat sparsely, to be malnourished. 2. Abstain from food for any purpose (Modern explanatory dictionary of the Russian language by Efremova).

Almost immediately, the subjects reported a decrease in both physical energy and motivation. The researchers noted the strongest apathy among the subjects, interspersed with paradoxical periods of irrational irritability. "The food queue has become a source of discord," they write in Men and Hunger. They often quarreled at the table, they were annoyed by each other's voices and the increasingly strange eating habits that they had.

"They could babysit [the food] like a child, or shake it like gold. They played with her like children building cakes," one participant wrote. Over time, licking plates became commonplace, as men were looking for ways to extend the meal time and/or feel more full. They diluted potatoes with water, kept bitten pieces of food in their mouths without swallowing them for a long time, or tried to combine food on a plate, "making strange and seemingly tasteless combinations," the researchers report.
Food has become the only source of passion and motivation. Many men began compulsively collecting recipes ("I didn't sleep until 5 in the morning, studying cookbooks," wrote one). Meanwhile, all the other elements of life seemed to have disappeared in a simple background noise. Again and again, the researchers reported indifference and boredom, their sexual desire evaporated. At parties, the subjects found maintaining conversation difficult and pointless. They all preferred solo trips to the cinema, adding that although they could recognize comedy, they stopped feeling the urge to laugh. 
Finally, the fasting phase ended, and a 20-week rehabilitation period began. It was at this stage that the most unexpected discovery was made: if the physical recovery progressed at least slowly, then the psychological state of the subjects worsened. The licking of plates continued, irritability turned into aggression, and mood swings became more serious. One day, while chopping wood, Samuel Legg cut off three of his fingers. "I admit I wasn't myself at the time," Legg later explained. "I'm not ready to say that I did it on purpose. But I'm not ready to say the opposite."

To everyone's relief, the subjects' moods and social behavior stabilized three months later. But in relation to food, the men agreed that they were not "back to normal." Many ate "more or less continuously," and a subset of the subjects continued to overeat even eight months later.

Here are a couple of "malnourished" during the experiment:

It is worth mentioning that in 2003-2004, interviews were conducted with some of the participants in this study, and at that time half of them (19 out of 36) were still alive – at the age of more than 80 years. Some believe that this fact is a reflection of the benefits of fasting, since the average life expectancy of men in the United States born in the 1920s was about 75 years in 2004. However, I don't think so.

Firstly, if 100% of the participants in the experiment had survived until 2004, then one could still be surprised at this. And the fact that half of that cohort lived longer than the average value for the population does not mean anything: due to infant mortality (and, perhaps, those who died in WWII – I'm not sure if they were included in the calculation of the average life expectancy), the average life expectancy is usually lower than the median value (i.e., the age to which 50% of the cohort born in a certain period). Therefore, the median value of the pancreas for those born in 1920 is about 80 years old, I think, and is. And the median value is median because half of the population lives longer than it.

And secondly, even if these 19 people live longer than the average, do not forget that they initially had increased health – otherwise they would not have passed the primary selection of 400 volunteers.

So what is a body-starvation?

It's funny that those who blame me for my use of the term "fasting" for themselves define it as "something that reduces insulin-like growth factor (IGF-1)". For example, the Fasting Mimicking Diet (FMD) is a diet that simulates fasting. Despite the fact that this diet itself, by definition, is not fasting (the first day is 1100 kcal, 2-5 days are 700 kcal). And with IGF-1, everything is not smooth there – after returning to a normal diet, IGF-1 also most likely returns to its original value in a few days. I know of at least one case where the IGF-1 value a few days after the completion of FMD was higher than the initial one before the diet. I also know of another case when IGF-1 decreased by 35% on a five-day "anti-diet" of lamb with wine. By the way, alcohol reduces IGF-1:

So maybe fans of his decline should think about replacing a diet simulating starvation with a diet simulating binge drinking? Kidding, kidding.

In any case, in the study referred to by supporters of FMD, the value of IGF-1 after 5-8 days after returning to a normal diet was only 15% lower than the initial value (see graph D):

However, for some reason the IGF-1 values of the entire group are summed up there, and it is the average of the group that is compared. That is, the average temperature in the hospital: the level of the entire group before the diet is taken for 100%, and then the values of IGF-1 after the 1st FMD cycle and after 5-8 days of the usual diet after (for some reason) the 3rd FMD cycle are determined as a percentage of it. It seems to me that this is a very strange approach: after all, one outlier can greatly affect the entire statistics of the group. For example, if almost everyone had an average level of 100 units, and it dropped to 90 units, and someone had 200 and fell to 90, and here we have a pattern of decline of the entire group distorted, and the volatility is masked. It seems to me that it would be more correct to look at the individual values of each participant's decline.

It is also strange that the IGF-1 level immediately after fasting was taken after the first FMD cycle, and the IGF-1 level after 5-8 days of a normal diet was taken after the third cycle (that is, 75 days after the start of the study). But even so, the average value of IGF-1 has a spread (standard error) plus or minus 6-7% after 5-8 days after resuming the diet. Well, the fact that IGF-1 after 5-8 days out of fasting is 15% lower than the initial value 3.5 months ago – this says little about anything. I think that after a few more days of the usual diet, IGF-1 will return to its original level.

By the way, the prolongation of life in mice from FMD is also not so good:

And how much these 11% of the median prolongation of the pancreas of mice can be translated in primates is another big question.

By the way, about 11% prolongation in primates. Someone saw an 11% median prolongation in females from the UW study in the first graph below, and accused me of inaccuracy when I said that "calorie restriction [in these studies] did not prolong the life of primates by more than 5%."

Personally, I can't bring myself to call what we see in these females an "11% extension". The survival curves of the groups are intertwined there, and there is no monotony on the basis of which we could talk about some guaranteed (albeit small) effect. The effect is negative, then positive, then disappears again. In any case, that 3% of the prolongation of the pancreas in males, that 11% in females, or -5%, as in other groups, are absolutely scanty indicators for me, for which it is absolutely not worth torturing your body.

But at the same time, I repeat – this does not mean that you can eat with impunity for your health as not in yourself! Not at all – overeating is very fraught with a reduction in your pancreas, and certainly a deterioration in its quality. Especially the abuse of sugar (that is, in fact, any simple carbohydrates that are broken down to glucose or fructose in a matter of minutes after entering your body). And yes, evil sugar increases the likelihood of you having diabetes and Alzheimer's – it's not for nothing that the latter is called "type 3 diabetes".

Can I have meat?

But the fact that meat is even more harmful than sugar, as some wrote to me, is not a fact at all. In a recent population study, it was shown that meat-eaters generally live a little longer than vegetarians, and only "fish vegetarians" (fish declare a silent protest against this term) live a little longer than meat-eaters (that is, their mortality risk in the Cox proportional hazards model is lower):

“there was no significant difference in all-cause mortality for vegetarians versus non-vegetarians [HR=1.16 (95% CI 0.93–1.45)]. There was also no significant difference in mortality risk between pesco-vegetarians [HR=0.79 (95% CI 0.59–1.06)] or semi-vegetarians [HR=1.12 (95% CI 0.96–1.31)] versus regular meat eaters. We found no evidence that following a vegetarian diet, semi-vegetarian diet or a pesco-vegetarian diet has an independent protective effect on all-cause mortality.”

At the same time, the statistical significance of all these conclusions is quite low, but it is quite enough to assert that there is no significant difference between the pancreas of vegetarians and meat-eaters.

In conclusion, I want to say that I am very grateful for all the criticism I have received. After all, it helps me to polish my understanding. So to all who wrote – thank you very much!

Portal "Eternal youth" http://vechnayamolodost.ru  30.05.2017