10 July 2008

Let's sit down, friends…

(End of the article "Dietetics with mythology")Most often, people go on a diet in order to lose weight, and in pursuit of beauty, many are ready to make any sacrifice.

Is it worth it? Most popular diets are harmful to health, and even the most harmless and scientifically based weight loss programs, as it turned out, generally do more harm than good – including for the waistline.

Therapeutic fasting

Any supporter of this method will explain to you that the term "fasting" is inappropriate here: it should be said in a scientific way: "unloading diet therapy". Any opponent will convincingly prove that the term "therapeutic" is inappropriate here: such a blow to the body is more likely to cripple than cure. Although fasting enthusiasts – both doctors and lovers of experiments on their own body – consider it unsafe, but a powerful treatment not only for obesity, but also for many diseases themselves.

One of the first consequences of fasting is that after about a three–day period of adaptation, when the patient's hunger is turned off, chronic poisoning with intermediate products of fat breakdown – acetone and other ketones, which primarily affect the brain, liver and kidneys, is superimposed on the general weakness. And in general, after a long hunger strike, from 2 to 6 weeks, there are no organs and systems with undisturbed functions in the body. It may be that in some diseases, in some patients, such a shake-up gives a positive result, but supporters of hunger treatment among doctors, including specialists in obesity, were in an absolute minority even during the heyday of fashion for this dubious method. Fortunately, even the most enthusiastic experimenters usually have the sense to listen to the urgent advice to engage in fasting only in a specialized medical institution, under the constant supervision of a doctor. Then, most likely, it will be possible to stop the process of "treatment" before irreversible changes begin in the heart, eyes, brain and other vital and poorly recovering organs.

And for the treatment of obesity, complete starvation is far from the most effective method. At the same time, the weight decreases, of course, faster than on any diet, but at least half of the lost kilograms are not adipose tissue, but muscles, skin, liver, kidneys and further according to the anatomical atlas. Much better results are obtained not by complete starvation, but by the so–called pronounced low-calorie diets, with specially developed mixtures containing the right amount of vitamins, minerals, fiber, proteins and even a little carbohydrates and 1-2 g of fat for a total of no more than 800 (sometimes 200!) kcal per day. Despite these calories, patients on average lose weight by the same 10-15 kg per month as with complete starvation, but the fat in the kilograms they lost is 1.5-2 times more. Such a diet, although less dangerous than fasting, is too powerful a method, and it should be used only in emergency cases – for example, when obesity does not allow for surgery, which must be performed no later than a few months.

As with more gentle diets, the most important thing here is to limit the calorie content, sweetness and fat content of the diet for the rest of your life after achieving the result. Otherwise, the body, which has reached the opportunity to eat how much and what you want, will get fat again in six months or a year.

Atkins and Co.The low–carb nutrition system is perhaps the most controversial of the unorthodox dietary theories.

Robert Atkins was far from the first to suggest using a low-carb diet both for the treatment of obesity and as a lifelong nutrition system. A sharp restriction of the consumption of any carbohydrates as a method of weight loss was first published back in 1863 by the owner of the funeral home William Bunting in the brochure "A letter about obesity addressed to the public", compiled based on the results of personal experience in the fight against obesity. His ideas were so popular that the word "banting" in English became a household word, meaning "treating obesity with a diet."

Mr. Bunting and many of his followers managed to lose weight, but official medicine did not pay attention to another fashionable book. The carbohydrate-free diet attracted the attention of scientists only in the 1920s, after the publication of the results of a health survey by ethnographer Viljalmur Stefansson, who lived with the Eskimos for several years. To the surprise of doctors, eating meat, fish and fat did not affect his body at all. After that, for several decades, one or another nutritionist offered his own system of low-carbohydrate nutrition, but such a diet gained wide popularity after the publication of the book "The Dietary Revolution of Dr. Atkins" in 1972.

The Atkins diet and its numerous analogues (for example, the "Kremlin" diet) are the dream of a fat man who wants to lose extra pounds: eat up on both cheeks and lose weight at the same time! But you can only eat proteins and fats – even salami, even fried geese, and you need to give up almost any carbohydrates – both "fast" (simply put, sweets), and "slow" recommended by orthodox nutritionists – cereals and other grain products. It is possible and even necessary to eat vegetables and fruits (if possible, not sweet), and after achieving the desired effect, you can slightly relax the strictness – add a slice of bread and even half a teaspoon of sugar to your daily diet.

The main reason for the debate about low–carb diets is disagreement on a fundamental issue: what is a normal human diet?

Excess carbohydratesEasily digestible carbohydrates (starches and especially sugars) are quickly broken down in the digestive tract to glucose.
In response to an increase in its concentration in the blood, the pancreas begins to synthesize insulin, which ensures the penetration of glucose into cells. In "cellular power plants" – mitochondria – glucose decomposes to carbon dioxide and water, and the energy released in this case is stored in adenosine triphosphate (ATP) molecules. Excess carbohydrates are converted into "animal starch" – glycogen. If the glucose level remains high, the mechanisms of its conversion into fats are activated, which are deposited for a rainy day in adipocytes – cells of adipose tissue. Chronic poisoning with excess glucose often leads to type 2 diabetes (decreased sensitivity of cellular receptors to insulin) and other obesity-related diseases.

Lack of carbohydrates
If the blood sugar level decreases so much that glucose is not enough to supply cells with energy, the pancreas begins to produce glucagon, an enzyme that converts glycogen stored in the liver and muscles back into glucose. But the amount of glycogen in the body is about 150 g, in terms of calories – about 250 g of white bread, and when its reserves are depleted, glucose synthesis from some glucogenic amino acids (gluconeogenesis) begins in the liver and another, energetically more beneficial process is the breakdown of fats with the formation of ketones (ketosis). Weight loss in the first stages of carb–free diets is the result of the fact that the body, having rebuilt itself to this type of metabolism, decomposes its own fats at the same time. At the same time, the fat cells themselves, as with other diets, do not go anywhere and restore reserves at the first opportunity.

Most cells of the human body can, although with difficulty, use ketones as an energy source (neurons are not capable of this – they need glucose). But, according to the generally accepted opinion, the ketogenic metabolic pathway is a backup (for example, in case of a long hunger strike), and ketone compounds are harmful to health (acetone addiction is a sure path to personal degradation and further, to the next world). Proponents of the revolutionary theory of nutrition convince the opposite – that the use of glucose as the main source of energy for a person is completely abnormal, and the state of ketosis is natural and useful. However, it has not yet been possible to confirm this opinion with clinical studies. As well as the fact that long-term observance of the "Eskimo" diet is not harmful for those whose ancestors did not observe it for tens of thousands of years (Eskimos, genetically not adapted to a diet of walrus and pickled fish, died out long ago).

In the books of Atkins and his associates, it is usually emphasized that people with kidney, liver and a number of other diseases are not shown such a diet, and even healthy people should carefully listen to the state of their body and, if necessary, increase their carbohydrate intake. But in general, supporters of low-carb diets convince that their way of eating can and should be observed for life, and with such trifles as bad breath, constipation, lack of a number of vitamins and minerals and other obvious consequences of a carb-free diet, it is easy to cope with chewing gum, olive oil at night and vitamin tablets.

Opponents accuse propagandists of low-carb diets of suppressing numerous facts about severe kidney and liver damage, decreased immunity, physical and mental performance, heart attacks and other unpleasant consequences of such diets, and even call the Atkins diet and its like a ticket to the next world.

Dr. Atkins died at the age of 72, in April 2003. On the Internet and the media, gossip immediately spread that he died either from a heart attack, or from a stroke, but undoubtedly because of atherosclerosis caused by his diet, and he weighed 180 cm tall, or 116, or 120 kg. Supporters and heirs of Atkins amicably objected that the cause of death was a head injury as a result of a fall on spring ice, that the doctor had not weighed more than 90 since he started eating according to his system at the age of 33, his heart and blood vessels and in general his health were in perfect order, and the source of the rumors, Dr. Fleming, in such a dirty way, he promotes his own, directly opposite, food system. And he himself, although he calls for vegetarianism, regularly eats meat.

Anti-Atkins

The other extreme is low–fat diets. One of the most famous and popular propagandists of "low–fat" diets, Dr. Dean Ornish, recommends consuming no more than 15-20 grams of fat per day, and exclusively vegetable - accordingly, you will have to switch to pure veganism (we talked about its health hazards in a previous article). More moderate versions of low–fat diets do not prohibit animal products, and fats are allowed to consume 20-40 g per day - 2-2.5 times less than in standard recommendations for healthy eating for people who do not suffer from excess weight, and 3-5 times less than in the usual European / American diet. Just don't think that fats are butter and vegetable oil. Forget about butter in general, and do not forget that there are even more vegetable fats in "lean". And walk around the grocery store like you're walking through a minefield: hidden fats are waiting for you everywhere! Even in lean beef, fat is 5-10%, in lean pork itself – 20-30%, not to mention sausage, sausage and confectionery products and many other products. Therefore, a low-fat diet involves a radical restructuring of eating habits. It is also recommended to limit the amount of easily digestible carbohydrates, but without fanaticism. But the consumption of fruits, vegetables, legumes, soy products, whole grain bakery products, etc. is welcome.

Opponents of low-fat diets claim that none of the many studies have been able to show any connection between a decrease in fat intake and health or body weight, and the authors who found such a dependence did not take into account the influence of other equally important factors such as physical activity and consumption of fresh vegetables and fruits. The opinion of skeptics about the propaganda of fat phobia that has been going on for half a century has been best formulated by Richard K. Bernstein, a type 1 diabetic and a well–known diabetes researcher: "Call it a big fat lie... that Americans are obese as a result of excessive fat consumption is just a myth." It sounds convincing: back in 1997, the American Journal of Medicine published an article "Opposite trends in the spread of obesity and fat consumption: an American paradox" (Heinie A.F.; Weinsier R.L., AJM 102(3):259-64).

In particular, the following figures are given in it: from the mid-1970s to the early 90s, the total caloric content of the average American's diet decreased by 4%, from 1854 to 1785 kcal. The proportion of fat in these calories fell by 11%, from 41 to 36.6%. The number of obese people in the United States has grown by almost a third during this time, from 25.4 to 33.3% of the adult population. True, the fashion for low-carb diets that came in the early 1990s led to an increase in fat consumption and a decrease in carbohydrates, but it did not affect the dynamics of obesity in any way.

In the first version of the "Nutrition Pyramid", a visual guide to the principles of a healthy diet, it was based on grain products.

In the newly developed second version, the base of the pyramid is made up of pictograms of running men – a reminder that it is necessary first of all to spend as many calories as you get. The rest is not so important.

Montignac

His recommendations do not cause outrage among doctors – but only the actual recommendations, which in general are reduced to reducing the caloric content of the diet due to easily digestible carbohydrates and other well-known tips that the most orthodox of nutritionists will give you. But the theoretical justification of the next "revolutionary" dietetics among specialists causes at least bewilderment. What is at least the main position of Montignac worth: the calorie theory is a universal misconception! The energy contained in food does not affect the acquisition of excess weight!

To get out of this paradox, Montignac offers his own, contrary to the ABC truths, the mechanism of insulin's connection with obesity, denies the generally accepted division of carbohydrates into "fast" and "slow" (according to his unconfirmed statement, both sweet tea and whole grain porridge are digested in 20-30 minutes), and even simply distorts, stating that white bread and bread made from coarse flour do not differ in energy value (look at the packaging of both – you will find almost a twofold difference). And as a basis for the classification of carbohydrates into "bad" and "good", he takes the glycemic index – a long-known indicator reflecting the ability of foods to cause hyperglycemia (an increase in blood sugar levels). Easily digestible and high–calorie carbohydrates have a high glycemic index – glucose (100), honey (90), sugar, white bread and potatoes (75), bananas (60), etc. Low - for example, buckwheat porridge and beans (40), bread from coarse flour (35), fruit (30), vegetables and mushrooms (15). Abandoning the first in favor of the second, you can, without feeling hungry, noticeably reduce the "non-existent" caloric content of the diet.

So there was no need to talk about the perverse theory. Moreover, most readers of Montignac's books skip the boring and obscure beginning and immediately proceed to practical advice, including recommendations based on nothing on the compatibility of products, and culinary recipes.

Their name is Legion

There are a great many diets in the world – both as nutrition systems and focused only on weight loss. The vast majority of them are either based on absolutely unscientific ideas (such as diets by blood type or a fashionable "Hemocode"), or are not based on anything at all, except the urgent need to fill out a column in the next issue of a glossy magazine. There are perhaps several hundred mono-diets alone, from Orange and Pineapple to Apple and Egg. There are several dozen different alcoholic drinks (the first of them was invented by Herr Schroth, a very full German cabby – that, in general, says it all). But to enumerate and analyze at least the main trends in pseudo–dietology is a meaningless matter.

According to the authors of many, including very popular, nutrition systems, a completely different field of medicine is crying in general. Let's go straight to the end of the list (or, conversely, to the top?) – breatharianism (in English it doesn't sound so clumsy - Breatharianism). The founder of the sect, the Great Jasmukhin (by passport – Ellen Grove, by education – lawyer, place of permanent residence – Australia), was born in 1957, at the age of two became a vegetarian, in 1993 she began to eat, inhaling the energy of sunlight, and a year later she meditated until contact with some Ascended Masters. At their behest, he writes books and travels around the world, bringing the light of "pranic nutrition". At least three believers in her teachings died of exhaustion. Guru Jasmukhin is very sorry about this, but he does not refuse to propagate his ideas and continues to eat only prana herself.

And now – the bad news

It is impossible to lose weight by going on a diet! In any case, for a long time and for the vast majority of those who dream of getting rid of extra pounds and centimeters. The main reason for this is the long–known "yo-yo effect". As soon as the body begins to receive more calories than it spends, it (especially with a hereditary tendency to obesity) immediately begins to create reserves. The more often periods of fasting and excess nutrition alternate, the more actively weight gain occurs, and mainly due to visceral (surrounding abdominal organs) fat, which is more harmful to health than subcutaneous. A round abdomen (male-type obesity) and cyclic weight loss and weight gain are associated with an additional increase in the likelihood of obesity–related disorders in the immune system and diabetes, as well as hypertension and atherosclerosis - and, as a consequence, strokes and heart attacks.

Whatever school the nutritionists adhere to, they all say the same thing: after you lose weight, you need to continue to observe dietary restrictions! Doctors are well aware that not all patients follow this advice, but how "not all" became clear after the April (2007) issue of American Psychologist, the journal of the American Psychological Association. On the website dieta.ru you can read the translation of the article “Medicare's Search for Effective Obesity Treatments. Diets Are Not the Answer” by researchers at the University of California at Los Angeles led by Traci Mann, associate professor of psychology at UCLA. Analysis of 31 long–term studies of the results of weight loss using various diets, in combination with physical education and other factors and without them, on hundreds or tens of thousands of people with various degrees of obesity and simply overweight, allowed us to conclude: the long-term effect of diets on average is almost zero, and often negative! Only a few participants of weight loss programs manage to preserve the results achieved during the course of diet therapy, and most of them return all the lost kilograms in a few years and even overtake those fat people who did not go on a diet in weight.

During the first six months of participation in various programs, patients on average lost 5-10% of their original weight. However, very many (from 1/3 to 4/5, depending on many factors, including the time of observation of long–term results) quickly gained more than they lost. And it should be taken into account that these are the data of published articles ("unsuccessful" results are not printed much more often), and some of the works had to be excluded from the analysis due to particularly gross methodological violations. In reality, the picture is probably even worse.

For example, in many studies, participants themselves reported their weight by phone or by mail, and for sure many of them lost a few pounds. In all studies, the number of patients who remained under observation was very low (in eight studies – less than half), and there is no doubt that those participants who gained more kilograms refused to continue contact with doctors more often. Follow-up periods were often not long enough, and in studies where this period was only six months, the low effectiveness of diets was much worse noticeable than with observations for 2-5 years. In one study, obese patients were observed for different periods of time after the end of a hospital course of diet therapy. Among the patients who were followed for less than two years, 23% weighed more than before the start of treatment. Among those who were observed for two years or more, there were already 83% of them. The authors of several articles even came to the conclusion that dieting is a reliable indicator of weight gain in the future.

Tracy and her team analyzed a pile of literature not out of scientific curiosity, but to solve a practical question: does it make sense to spend money from the state health insurance program on nutritionists and their methods – despite the fact that the link between obesity and increased morbidity and mortality is beyond doubt. The gist of the answer: "We recommend that Medicare does not fund weight loss programs through diets. The benefits of dieting are too small and the potential harm is too great to recommend a diet as a safe and effective treatment for obesity."

Moreover, against the background of the general fight against obesity in rich countries, another problem has recently appeared: frequent cases of dystrophy up to a fatal outcome, and not only among models, but also among ladies and girls who have reached a real mental illness in an effort to lose weight – anorexia nervosa (Greek: an- – negative prefix and orexis – appetite). The French Parliament is already debating a bill on criminal liability for inciting a person to actions that led to his death from anorexia. Even if a fatal outcome was avoided, the provocateur faces two years in prison. The law does not persecute those who advise people on correct, harmless diets. His task is to punish those who force people to refuse food in order to lose too much weight, as well as those who openly promote anorexia.

A spoonful of honey

Mobile fat men are healthier than skinny sluggards, and live longer – this is also a long-known truth. It was recently confirmed by scientists at the University of South Carolina. They followed a group of 2,603 elderly people for 12 years, assessing various indicators of their lifestyle and health status – and, alas, mortality rates. The strongest influence on life expectancy was not waist circumference and body mass index, or even smoking and drinking within the personal norm, but physical activity. The old-bodied, obese, but regularly spending at least half an hour on any physical activity, from golf to gardening and just walking, had a lower mortality rate than people with normal or underweight, spending all day watching TV. And in groups with minimal and maximum physical activity, the probability of dying earlier than peers differed by 4 times, regardless of thickness.

Similar articles regularly appear in journals in various branches of medicine with conclusions that moderate fullness (not to be confused with severe obesity!) provided sufficient physical activity is not harmful to health and even useful. If you want to lose a couple (or even a dozen) extra pounds – think about whether it's worth tormenting yourself with doomed dieting?

Alexander Chubenko
Portal "Eternal youth" www.vechnayamolodost.ruThe journal version of the article was published in Popular Mechanics No. 7-2008

10.07.2008

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