Why are low-carb diets so popular and do they work?

More than one star has already confessed their love for low-carb ketogenic diets. But is this method really so good? Anthropology professor Hermann Ponzer has doubts. And his opinion can be trusted: the scientist has been researching the influence of nutrition on the physiology of people for several years.

The result of the professor's labors was the book “Sapiens on a Diet. World History of Weight Loss, or Anthropological View of Metabolism ", which was published in Russian by the publishing house" Bombora ". With his permission, Lifehacker publishes an excerpt from chapter six comparing different diets and their effectiveness.

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Why are low-carb ketogenic diets so popular? There are a lot of stories on social media about weight loss, waist reduction and diabetes cure - all thanks to this type of diet. Without a doubt, most of these online reviews are sincere and real. Losing weight and improving metabolic health appear to be life-changing for many people.

But while the results may seem magical, the reason low-carb diets work is simple: they decrease energy intake and create a negative energy balance. Every day, you burn more calories than you consume.

Low-carb diets can be especially effective in the short term because they force the body to burn glycogen. With an extremely low carbohydrate diet (20 g or less carbohydrates per day), the carbohydrate metabolic pathway is closed. When this happens, glycogen stores are depleted - the last passengers that are transported from the carbohydrate "metro line" to the mitochondria. Unlike fat, this compound retains water. Since the body stores it in its hydrated form, with three or four parts of water, burning it also results in water loss and rapid weight loss.

Low-carb diets are often effective in the short term - they force the body to burn glycogen.

Once glycogen stores are depleted, the body relies on the fat metabolic pathway for energy. You will start burning stored fat, but only if your daily energy expenditure exceeds your intake.

This is where the much-publicized magic of low-carb diets comes in: people claim to be losing weight but not reducing their calorie intake. As proof, they describe all the high-fat foods they eat and claim they never feel hungry. They often emphasize that they “don't count calories,” but at the same time seem confident - even categorical - that they are consuming exactly as many calories (or even more!) As before.

Success stories like these are always very rewarding, and if you find a diet that works for you, stick to it. However, there is no easy way to lose weight in which someone loses weight without consuming fewer calories than they are burning. And it doesn't matter which ones calories. These are the laws of physics.

People who are on low-carb diets may feel like they are consuming the same amount of food as before, but we are all rather imprecise in estimating the calories we eat per day. Of course, you can lose weight without paying attention to this aspect. Just like emptying a bank account without paying attention to the balance. But you can't lose weight without getting fewer calories than you burn.

Low-carb and ketogenic diets follow the same rules as other nutritional systems, and they work equally well (or poorly) compared to each other. We saw this in the study described earlier.

However, even larger trials examining a wider range of diets show the same results. In a 2005 study, Michael Dansinger and colleagues randomly assigned 160 adults living in and around Boston and translated M. L. Dansinger et al. (2005). Comparison of the Atkins, Ornish, Weight Watchers, and Zone Diets for Weight Loss and Heart Disease Risk Reduction: A Randomized Trial / JAMA each of them for a year for one of the four popular power systems: Atkins, Ornish, Weight Watchers and the Zone Diet. The Atkins diet is low-carb, the Ornish diet is low-fat, and the weight watcher and zonal diets fall somewhere in between.

Unsurprisingly, there were many differences in how well people adhered to their dietary systems, but the numbers were the same (each of these diets was easy to adjust). It is important to note that the type of diet did not affect weight loss in any way. Regardless of the diet, people lost weight. They all work if you stick to them.

Even the worst diets can lead to weight loss and improvement metabolismif reducing the number of calories consumed. The so-called monotrophic diets with one permitted food (or several foods of one groups) often lead to weight loss because people get tired of eating the same thing over and over and end up eating smaller. The potato diet is a popular example. Illusionist Penn Gillett reportedly lostS. Rinkunas. Eating Only One Food to Lose Weight Is a Terrible Idea / The Cut over 45 kg, eating only potatoes (which, it should be noted, is full of starches).

Mark Haub, a professor at Kansas State University, ate for 10 weeksM. Park. Twinkie Diet Helps Nutrition Professor Lose 27 Pounds / CNN only junk food to prove that only calories matter in weight loss. He even ran a Facebook page so anyone could watch his progress. Every 3 hours, he ate a cream-filled sponge cake instead of regular food, and his last meal was chips, sugar-coated cereals, and cookies.

It sounds like a health disaster (and I don't recommend such a diet!), But a key piece of the puzzle were calories: Haub limited himself to 1,800 kcal per day, which is significantly lower than his daily energy costs. By the end of 10 weeks, he lost 12 kg, his body mass index dropped from overweight (28.8) to normal (24.9). In addition, his level of cholesterol and triglycerides.

It is possible that low-carbohydrate diets are beneficial for patients with type 2 diabetes, since a large a dose of carbohydrates can lead to a sharp rise in blood sugar levels in people with impaired response to insulin. (Even in people without diabetes, restricting carbohydrate intake results in lower blood glucose levels.) In fact, as early as the 18th century, low-carb diets were popular. W. Morgan, Diabetes Mellitus: Its History Chemistry, Anatomy, Pathology, Physiology, and Treatment (The Homoeopathic Publishing Company, 1877) when treating this disorder.

Virta, a health care initiative founded by Stephen Finney to explore the benefits of a ketogenic diet for diabetes, gave a number of encouraging results. Many of the men and women participating in the Virta Low Carb Program have lost weight and reduced or even eliminated S. J. Athinarayanan et al. (2019). Long-Term Effects of a Novel Continuous Remote Care Intervention Including Nutritional Ketosis for the Management of Type 2 Diabetes: A 2-year Non-Randomized Clinical Trial / Frontiers in Endocrinology the need for insulin and other medications for their disease.

We cannot say that low-carb diets have cured them because high blood sugar and drug needs would not be long in coming if they returned to the typical high-carb diet. But whatever we call it, the results are promising and the benefits are real.

However, it is still not clear why the Virta program works: because it is based on low-carb foods or because they are low in calories. The study was not designed to compare low-carb diets with others. We know that significant weight loss can prevent R. Taylor, A. Al-Mrabeh, and N. Sattar (2019). Understanding the Mechanisms of Reversal of Type 2 Diabetes / The Lancet Diabetes & Endocrinology further development of type 2 diabetes in overweight and obese adults, and it doesn't seem to matter how you achieve that.

In Dansinger's study, which randomly assigned people to low-carb, low-fat, or mixed diets, men and women who managed to adhere to their nutritional system lost weight, and indicators of inflammation, the level of "good" cholesterol (HDL) cholesterol, insulin sensitivity and indicators of the three main risk factors for cardiometabolic diseases have improved.

This progress was directly related to the degree of weight loss, rather than the type of diet. In a dietary study where groups of men and women ate low-carb or low-fat diets, all subjects experienced similar improvements in cardiometabolic health. There were 36 people in both groups with metabolic syndrome. Metabolic syndrome is a complex of metabolic disorders in which the risk of developing cardiovascular diseases and type 2 diabetes is increased . 12 months after the study, no traces of the disease remained.

Losing weight will have a positive impact on the health of people who are overweight, obese, diabetic, or other metabolic diseases.

And, apparently, it does not matter so much whether you are constantly restricting calories or skipping some meals altogether. Intermittent fasting, in which you abstain from food for most of the day, is very popular for weight loss. This method is often advertised in the same way as low-carb diets: eat what you want (when you're not starving), don't bother counting calories, that's how our ancestors ate!

But, since science has long figured out this theory, the reality is actually much simpler. Randomized studies similar to Dansinger's trial showed that people who periodically starve were not much better off I. Cioffi et al. (2018). Intermittent versus Continuous Energy Restriction on Weight Loss and Cardiometabolic Outcomes: A Systematic Review and Meta-Analysis of Randomized Controlled Trials / Journal of Translational Medicine lost weight compared to those on traditional calorie-limited diets. Both groups showed similar results: improved insulin response, decreased sugar level in the blood and an increase in the amount of "good" cholesterol.

If you are overweight, calorie restriction leads to weight loss and positive cardiometabolic results, no matter how you lose weight.

None of this is promoting any particular diet. If you can find a nutritional system that works and supports you at a healthy weight and prevents metabolic disease from developing, then stick to it.

All of these studies prove one thing (what we are missing). All diets work because they limit calories. However, adhering to a specific nutritional system can sometimes be difficult because evolved metabolism usually fights the effort to lose weight by encouraging us to eat more.

Instead of believing in the magic of low-carb diets, it's worth considering why some people on low-carb diets can lose weight without feeling like they're consuming fewer calories. After all, if you are dieting and not feeling unhappy, then this is real success and you need to hold on to it.

Sapiens on Diet is a fascinating analysis of a wide variety of factors that affect the rate of weight loss, from metabolism to the development of technology. If you want to better understand your body, you will definitely like the book by Professor Ponzer.

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