The human body can survive without food for a certain period of time before starvation causes serious damage to the body.
In fact, when done properly and under medical supervision, fasting is thought to provide people with a variety of health benefits—but new research suggests that the benefits may not be achieved with short or frequent intermittent fasting.
A new study by researchers in Europe and England found that it took more than three days for all major organs to change protein production in a way that seven days of water-only fasting could predict better health.
These changes were observed in all 12 healthy participants (five women and seven men) whose blood was drawn before, during and after fasting.
“For the first time we were able to see what was happening. The level of molecules in our body when we fast He explains Claudia Langenberg, Epidemiologist, Queen Mary University of London.
“Our results provide evidence for health benefits of fasting beyond weight loss, but these are seen after three days of total caloric restriction – later than we previously thought.”
That is a long time for the human body to lose calories, which introduces some serious risks that are not worth the desired results.
When done safely and under the supervision of a health professional, fasting can have health benefits, but the risks need to be carefully considered for each individual. Physicians General advice Children, young people, pregnant women, or people with diabetes or eating disorders do not partake in intermittent fasting.
There is a risk of dehydration during fasting, because About 20 percent Most of our normal fluid intake comes from food, so individuals should make sure they are consuming plenty of water.
Fasting for days can be dangerous, and its benefits are still unclear. That said, if more research is done, scientists may be able to replicate the benefits of fasting without requiring anyone to cut calories.
In recent years, a lot Studies they have proposed that That intermittent fasting — as opposed to extended fasting — may improve some people’s health, according to the study. These include weight loss, blood pressure reduction, improved Bone density, and appetite control. Some experiments have found evidence of short-term hunger pangs Time can. Reduce the natural aging process And Maybe it can be extended A person’s lifetime.
For all that, scientists have very limited understanding of what exactly happens to the human body as it adapts to starvation. Clinical trials on the topic are limited, which means health professionals do not have evidence-based advice to give patients.
The new study found that of the 3,000-odd proteins measured in the participants’ blood, a third showed “profound systemic changes” after seven days of eating nothing but water. However, protein changes that are thought to have significant health benefits were observed after three consecutive days of fasting.
These include protein changes associated with rheumatoid arthritis and improved cardiovascular health.
The results support it The past ExperimentsIt also suggests that fasting may take several days before it becomes more beneficial than reducing calorie intake.
Most proteins return to baseline the moment a person starts eating again, suggesting that biological changes from fasting must be sustained for a period of time to achieve long-term health benefits.
“Lack of food is the default throughout human evolution, and our bodies are the result of a selection process for high metabolic flexibility to survive without it for long periods of time.” Explain The authors of the study.
“Our results provide an opportunity to systematically identify the potential health benefits of fasting and to translate this knowledge into prospective interventions, including longer fasting programs or patients unable to simulate fasting.”
Given the extremely small sample size of the current study, the results are unlikely to be representative of the effects of fasting on different populations. The international team of scientists hopes that their results will provide a useful reference point for future research on fasting.
The study was published in Natural metabolism.