In the comments to my posts about calorie restriction ( 1
), a thought was sounded a couple of times, that it would be nice if I cited research data and many days of complete fasting. Well, I will try.
I will say right away that there are a lot of enthusiastic reviews on the network about how long starvation helped someone ( 1 , 2 , 3 ). Negative (or at least neutral) is many times less. I think this is not only a matter of fasting mega-usefulness, but also reporting bias - those who have become worse from starvation are not particularly eager to share experience: after all, it’s not unpleasant to talk about their failures, so there is also a risk of offending religious feelings of adepts of starvation, who will tell you that you did everything wrong, and in general lie.
The most balanced, in my opinion, scientific article on starvation was written back in 1982. In its abstract, the main points are clearly stated, some of which I noticed on myself:
Early weight loss during fasting is significant, averaging 0.9 kg per day during the first week and slowing to 0.3 kg per day by the third week; early rapid weight loss is mainly due to the negative balance of sodium. The metabolic early starvation phase is characterized by a high rate of gluconeogenesis with amino acids as primary substrates. As fasting continues, progressive ketosis develops due to the mobilization and oxidation of fatty acids. As ketones grow, they replace glucose as the primary source of energy in the central nervous system, thereby reducing the need for gluconeogenesis and reducing protein catabolism. Hormonal changes are observed, including a drop in insulin and T3 levels, and an increase in glucagon and reverse T3 levels. Most studies of starvation have used obese people, so their results may not always apply to thin or healthy people. Medical complications observed in fasting include gout and urate nephrolithiasis, postural hypotension and cardiac arrhythmias.
The laudatory song of starvation , with all its forms (full or partial, long or short), was written in 2014 by Walter Longo, the creator of the Fasting Mimicking Diet, FMD, and part-time head of the company promoting it. In his article, starvation is described exclusively in a positive way:
Fasting has been practiced for thousands of years, but only recently has research shed light on its role in adaptive cellular responses that reduce oxidative damage and inflammation, optimize energy metabolism and strengthen cellular protection. In eukaryotes, chronic hunger partially prolongs life expectancy, reprogramming the pathways of metabolic and stress resistance. In rodents, intermittent or intermittent fasting protects against diabetes, cancer, heart disease, and neurodegeneration, whereas in humans it reduces obesity, hypertension, asthma, and rheumatoid arthritis. Thus, fasting can slow down aging and help prevent and treat diseases, while minimizing the side effects caused by chronic dietary interventions.
At one time I became interested in the theme of starvation thanks to a book written by Upton Sinclair
more than a hundred years ago. It is called The Fasting Cure
, and here
it is in the public domain. Immediately make a reservation that today I am rather skeptical about her.
Also a few years ago I was intrigued by the story of the Scotsman Angus Barbieri , who was hungry for 382 days (yes, more than a year!), And lost weight from 207 to 82 kg. True, he died in 1990 at the age of 51. A clinical report on his fasting was published here - he did not starve anyhow, but was lying in hospital under the supervision of doctors.
After I had read all these interesting stories, it was almost impossible not to try this case on myself. I began to study the world of ketogenic diets, intermittent fasting, multi-day starvation, etc., etc. The intrigue was intensified by various studies showing the benefits of different calorie restriction regimes, as well as the harm from oversupply - how can you resist?
Somewhere towards the end of 2014, I decided to start with a periodic fast. Given my eternal dislike for breakfast, everything was easy. It was necessary only to hold out without food until lunch - and here they are, the cherished 12-14 hours of fasting (from 23:00 to 13:00).
The next stage was a longer-term fast. Here the stars agreed with my schedule of long-distance flights (once every 1.5–2 months) and my dislike for airplane food. Along with the scientific data, according to which food intake affects circadian rhythms, and the consequent assumption that it is better not to eat at a new place until morning at a new place, 36 hours of starvation loomed by themselves. Dined in the evening before departure, and do not eat before breakfast (or even lunch) at a new place.
After 6-7 such flights, I wanted more. The next milestone was a three-day fast. That is 3 days on the same water. It was already more difficult, but it was given. And about six months later, it was decided to take a new height - a week on the water.
But this time I wanted to see if any objective positive effect would be visible - what will be there with inflammatory markers, hormones, glucose, cholesterol. For this, I decided to donate blood before and after fasting.
What was my surprise when I received the “before” results and saw that in the last 2 years of my experiments, my cholesterol jumped strongly, and the “bad” increased by 60% (see the table: the blue column is “before” ):
Well, okay, I decided, after fasting, he definitely should return to normal, and then we'll see the dynamics. And prepared to starve for 7 days. As is clear from the title, I only lasted 5. I was sooooo bad. Especially after the 3rd day, and each subsequent was only worse. I didn’t have the strength, I didn’t sleep well, I was terribly irritable, and I finally learned what a “brain fog” is.
At the same time, I followed all the recommendations: I drank 3-4 liters of water per day, added electrolytes (sodium, potassium, magnesium) to it, but I didn’t get better. Therefore, having passed the tests for the morning of 5 days, I decided to stop this self-torture.
But then a new surprise awaited me: the analyzes worsened. Triglycerides jumped, “good” cholesterol decreased, and “bad” grew:
To say that this was a surprise is to say nothing. The next few days, I went through the entire Internet in search of at least someone with similar experience. And in the end I found it. It turned out that we are many, and we are called “hyper-responders”:Hyper-Responder FAQ
The term, “hyper-responder” has been used for the ketogenic / low carb, high fat (keto / LCHF) community to describe ...
In short, hyper-responders are those with a cholesterol jump (50–100%) when switching to a low-carb diet. According to various estimates, such people range from 5% to 33%, and many of them have at least one allele e4 of the famous apolipoprotein E gene (APOE), which correlates with elevated blood cholesterol levels, and also has been highlighted as the main risk factor for Alzheimer's .
But why does the hyper responder have an organism that way? No one knows for sure yet, but there is a hypothesis that since the bulk of cholesterol is produced endogenously by our body (and does not come from the outside), while reducing external, dietary cholesterol, the body tries to compensate for this decrease by increasing its own production, and in hyper-responders increased endogenous cholesterol production.
But the most interesting discovery was not this. The author of the above site cholesterolcode.com, Dave Feldman, developed (and tested) a very interesting hypothesis: the level of cholesterol and triglycerides in the blood reflects only your diet for the last three days and nothing more. Moreover, it reflects in inverse dependence: the more dietary cholesterol and fat you consume during these three days, the lower will be the values in the blood.
Therefore, it is not entirely correct to draw long-term conclusions based on your individual cholesterol and triglyceride values - at least several points are necessary - and 3 days before the collection of which you didn’t leave your usual diet much. By the way, for IGF-1 this is even more true - after all, its blood level is even more labile than cholesterol or triglycerides: alcohol intake can reduce it by 15% in a matter of hours. A dense protein dinner or exercise the day before analysis - to increase.
Returning to the cholesterol hypothesis of Dave Feldman, here is a graph of the values of fat eaten (yellow, in an inverted projection) and cholesterol 3 days later (in blue) from Dave's repeated measurements. Note the high degree of correlation:
By the way, here is his full presentation (25 minutes of pure time), I highly recommend:
Dave's hypothesis is indirectly confirmed by my experience, because since I had not eaten anything for 5 days, there was simply no place for external cholesterol to take. So the increase in its level was caused endogenously. To myself, I nasteziroval it.
How could this hypothesis be tested? Very simple - a couple of weeks to eat "from the belly". What can't you do for the sake of science! Only for experimental purposes was purchased a kilogram of mascarpone and a box of oatmeal cookies. Over the next 2 weeks, my 5 kilos, lost during 5 days of fasting, were quickly replenished with daily consumption of ~ 3000 kcal. And the tests confirmed that the sufferings were not in vain. The triglycerides returned to their original value, and the “bad” cholesterol dropped by almost a quarter:
What conclusions did I draw for myself from all this? First, you need to have extra weight for fasting. If you are initially thin, then you will simply have nothing to starve (my 84 kg with 15% bodyfat are close to the minimum, especially considering my speed of dropping weight at 1 kg / day). And secondly, different people can have very different responses of their bodies to starvation. And it is desirable to test these answers to some significant hungry adventures. Suddenly, you are also a hyper responder.
As a result, I abandoned all these diets and starvation. No, I still believe that sugar is evil, and that carbohydrates, especially “fast” ones, cannot be abused. This is the surest way to shorten your life or earn Alzheimer's .
But besides adhering to these truths for myself, personally, to put it mildly, I didn’t see much benefit from starvation or diets, and so far I don’t see much harm from their absence - below are 3 more biomarker measurement points without any diets:
Yes, in the analyzes, a new unpleasant bell - high insulin - begins to manifest itself, but there is a hypothesis that this may even be a consequence of my periodic fasting in the past, and not of my current diet. In any case, I’ll deal with him separately.
That was my experience. As part of the fight against reporting bias decided to share it.