Fasting DOES have major benefits… but there’s one major caveat that will be a deal-breaker for most people

Fasting like Mark Wahlberg and Chris Hemsworth may have multiple health benefits, scientists say — but only if you do it for at least three days in a row.

A new study in Britain shows that prolonged fasting not only burns off unhealthy fat, but also gives several organs, including the brain, a ‘significant’ boost.

But researchers from Queen Mary University of London found that the benefits only occur after at least 72 hours without food.

It means Wahlberg and Hemsworth — who both aim to avoid eating between 6 p.m. and 11:55 a.m. during intermittent fasting — may not take full advantage.

Chris Hemsworth has also previously followed intermittent fasting plans. (He is seen above in 2016 in Byron Bay, Australia)

Many other celebrities have also touted the benefits of intermittent fasting, including Hugh Jackman, Halle Berry and Kourtney Kardashian.

Professor Claudia Langenberg said: ‘Fasting, when done safely, is an effective weight loss intervention. Popular diets that include fasting claim to have health benefits beyond just weight loss.

‘Our results provide evidence for the health benefits of fasting in addition to weight loss, but these were only apparent after three days of total calorie restriction – later than we previously thought.

‘For the first time we can see what happens at the molecular level throughout the body when we fast.’

The study, published in the journal Nature metabolismResearch found that protein levels in various organs change after about three days of fasting, indicating that the entire body is responding to the fasting.

These proteins, including those that provide the support structure for neurons in the brain, help organs function more effectively.

It also helps regulate gender-specific hormones in the body, improving organ function.

The body also changes the source and type of energy, switching from glucose calories coming from food to its own fat stores.

The study’s subjects, who fasted for seven days straight, lost an average of 12.5 pounds. The weight stayed off even three days after the fast ended.

The article involved 12 volunteers – five women and seven men – who were in their 20s and 30s and weighed an average of 171 pounds at the start of the study.

Scientists took blood samples every morning and evening during the seven-day fast and a week afterward and two days before.

Fat mass had dropped by 5 pounds at the end of the seven-day fast and remained at this level a week later.

Muscle mass was reduced by 7 pounds at the end of the fast, but then recovered by 5 pounds in the following week. There were also shifts in other measures, such as bone mass.

Fasting is practiced by millions of people around the world for a variety of medical and cultural purposes, including health benefits and weight loss.

This study suggests that to reap the full benefits of fasting, a person may need to go without food for 72 hours – relying solely on water instead

Historically, fasting was used to treat diseases such as epilepsy and rheumatoid arthritis. The researchers said the protein changes may explain why it had a positive effect on this and other conditions.

They hope that their findings will lead to new treatments for people who cannot fast for long periods of time.

Dr. Maik Pietzner said: ‘While fasting can be beneficial for treating certain conditions, fasting will often not be an option for patients suffering from poor health. We hope these findings can be used to develop treatments that patients can benefit from.”