Limiting the number of times, we eat has become an attractive alternative for people who want to lose weight or simply be healthier: these are the options, according to science
Intermittent fasting is a type of diet that limits the amount of time you allow yourself to eat. The appeal of these diets is that you don't need to count calories or eat certain foods. But this method has so many variations that it is difficult to discern which is the best. Here's what the science says.
The 5: 2 diet
It is a popular variant of intermittent fasting that consists of maintaining a very low calorie diet (about 500 kilocalories) for two days a week (it can be any two days) and eating normally for the remaining five days.
Scientific studies have shown that the 5: 2 diet allows you to lose weight and that it also improves various health markers, such as lowering blood glucose and cholesterol levels. But generally, this diet is no more effective for weight loss than traditional dietary methods. This is because the 5: 2 diet reduces calorie intake to a similar extent to traditional diets.
There is evidence that running the two days on which very few calories are eaten consecutively can improve insulin sensitivity - a marker of risk of type 2 diabetes - to a greater extent than the classic diet. In addition, compared to the traditional diet, this method leads to a reduction in blood lipids (fatty substances found in the blood).
An important added benefit of the 5: 2 diet is that it allows you to consume food during the "fast" period, allowing you to take in critical nutrients. Diets often lead to loss of bone and muscle mass, as well as loss of fat, since it is difficult to maintain a balanced diet and, at the same time, reduce calorie intake. This result can derail long-term weight loss efforts, as muscle is more metabolically active (that is, burns more calories) than fat. Eating sufficient protein can help curb muscle loss during dieting, with the added benefit of reducing your appetite.
Fasting on alternate days
While the 5: 2 diet could be viewed as a "lifestyle intervention," alternate-day fasting (ADF) is used more generally for rapid weight loss. Alternate-day fasting is also known as the “morning-after diet” and requires alternating days between unrestricted eating and very few calories.
Most studies on alternate-day fasting use a criterion similar to the 5: 2 diet, allowing you to consume a small meal (usually about 500 kilocalories) on “fast” days.
Research has shown that alternate-day fasting can achieve significant weight loss over a period of 8 to 12 weeks. However, this fast poses a serious problem, and it is that following the diet tends to decline. Long-term studies have shown that, over time, calorie intake increases on “fast” days, reducing the caloric deficit achieved and slowing the rate of weight loss.
On fasting days, a small meal is usually eaten. Kyrylo Glivin / Shutterstock
Randomized controlled trials (the gold standard for clinical studies) have been conducted showing that alternate-day fasting does not achieve greater weight loss or health improvements than traditional diets when calorie intake is the lowest. same in both groups. However, fasting every other day usually results in a greater reduction in calorie intake than the traditional dietary method, which should translate into greater weight loss in the initial phase. But it is unlikely that there are many people willing to practice alternate day fasting in the long term.
The restricted feeding time (time-restricted eating or TRE) is fully fast for long periods (16 to 20 hours) and consume all periods calorie restricted, which are often called "power windows".
The most common variant of time-restricted eating uses a 16: 8 ratios between fasting and feeding (16 hours of fasting and 8 hours of feeding). Many people go through this cycle by skipping breakfast, delaying their first daily meal until noon and consuming all meals between noon and eight in the afternoon.
Studies have shown that calorie intake in a 24-hour period is reduced when people skip breakfast. But the amount of calories expended by physical activity also decreases, which will fully or partially compensate for the caloric deficit achieved by skipping breakfast. So skipping breakfast will generally not lead to significant weight loss. Skipping breakfast also reduces the effectiveness of insulin in regulating blood glucose levels after meals, indicating a negative effect on insulin sensitivity.
But there is an alternative method to time-restricted feeding that has shown promising results. A recent study concluded that fasting after two in the afternoon improved insulin sensitivity in a group of prediabetic men. This result could be due to a greater natural ability to effectively regulate blood glucose levels in the morning, due to daily variations in metabolism. Thus, limiting food intake to one feeding window in the morning and fasting in the afternoon may be a healthier variant of the restricted time eating method.
And the winner is…
As with all diets, success will be determined above all by monitoring. When you are looking to lose weight, fasting every other day is probably the one that will achieve the most immediate results, but to lose weight in a sustained way in the long term, the 5: 2 methods, which is less, may be more helpful. intense.
It has been observed that the follow-up could be greater in the restricted time feeding method, since some people may find it easier to limit their food intake completely than to restrict it severely. In this sense, some studies suggest that skipping dinner may be more beneficial to health than skipping breakfast.
It is important to note that most studies suggest that intermittent fasting is no more effective than traditional dietary methods. But intermittent fasting regimens that include long periods of fasting, such as the time-restricted feeding method with shorter feeding windows and the 5: 2 diet with two consecutive days of very low calorie intake, can have added benefits for health. A guide book available online called Alive After the Fall 2 will tell us how to survive a world war. The ebook is based on the prophecies of famous prophets in the Bible. Such prophets like Jeremiah, Isaiah and many more have big contributions to this book of survival skills. Alive After the Fall 2 has the information about the present, past, and future of our world. This includes the humanity we have and what is about to face.