Fasting, Autophagy and Loose Skin – How Fasting Can Promote Autophagy To Help with Loose Skin from Weight Loss

autophagy and loose skin

Autophagy and Loose Skin

You’ve finally lost some of those extra pounds, and starting to feel good about yourself. You feel good, that is until you notice that hanging loose skin around your upper arms or that extra sagging skin around your stomach that just won’t seem to go away.

That loose upper arm skin or “bat wings” are one example of loose skin left on your body from weight loss. But loose skin can be around the abdomen, thighs, buttocks, or in other areas. That stubborn loose skin can send our self-esteem spiraling downward. 

While surgery is one scientifically supported way to get rid of that loose skin, for many folks, surgery isn’t really a solution. It’s both expensive and risky.   Cheer up, because autophagy and fasting are also scientifically supported for helping with loose skin from weight loss.

Fasting and autophagy can help skin stay elastic and adapt to lower weight more quickly. While autophagy and fasting don’t literally “eat up” the loose skin, they can help prevent loose skin from forming as you lose weight  — all without surgery.

The Short Answer

Autophagy, from the Greek words “auto-” for self and “phagy” for eating, or “self-eating.” is the process by which the body begins to eat itself, destroying and recycling its own damaged cell bits and proteins, and allowing the body to build new, healthier versions. Autophagy can be induced by the absence of external food, in other words, by fasting for several hours. Anecdotal studies of people who lost 120 pounds or more in fasting clinics show that they were able to shrink their skin safely without surgery through accelerating autophagy.

Autophagy and fasting to reduce loose skin can work and are safe for most people (but always check with your doctor before starting a fasting program). There is some research on the benefits of autophagy on skin and skin elasticity, which can improve loose skin from weight loss.

The Long Answer

Research Studies on Autophagy

Scientists have been studying autophagy since the 1960s, and Belgian biochemist Christian de Duve developed the word “autophagy” then. Scientists have made considerable progress in their understanding of autophagy over the past few years, and in 2016 a Japanese biologist 

Yoshinori Ohsumi won a Nobel Prize in Physiology for his work in the field. Ohsumi, affiliated with the Tokyo Institute of Technology,  used baker’s yeast to identify genes essential for autophagy, studied, and explained the mechanisms for autophagy in yeast, and then showed how a similar mechanism is used in our human cells.

Autophagy is a relatively new field of study and, thanks to Ohsumi, is now a popular research topic. Researchers are continuing to learn more about it as time goes on.

Some experts have called autophagy cellular housekeeping or cellular quality control. Autophagy gradually reduces damage to cells and provides tissues with what they need to grow healthier cells. The more autophagy occurs, the more the body begins to heal itself, replacing damaged cells with new ones.

Although research is ongoing, autophagy has been credited with slowing down the progress of neurodegenerative diseases such as Alzheimer’s and Parkinson’s. Researchers are investigating a potential link between autophagy, intermittent fasting, and a reduction in calorie intake and the successful fight against cancer, as well as with fighting depression and schizophrenia.

Autophagy also has been linked with increased energy, a more robust immune system, and reduced inflammation and damage to joints. Studies also have shown increased autophagy to be a factor in improved digestion and weight loss.

Autophagy, more scientifically known as autophagic flux,  is a natural process and will occur to some degree without fasting. Scientists are unsure exactly how often autophagy occurs in humans, as it requires tracking the levels of tiny proteins.

While some researchers have done this tracking, a University of Chicago biologist Kay Mcleod says, “We all recognize that our ability to monitor and measure autophagy is not as good as it could be.” Additional tools are being developed, and she remains confident that these tools will help scientists more closely monitor this process in the future.

Research on Fasting, Autophagy and Loose Skin

There are several studies that looked at the effects and benefits of autophagy on loose skin.

A 2014 study that took place at Kyushu University in Fukuoka, Japan, found that aging fibroblasts, or cells in connective tissue that produce collagen and other fibers, suffer from a lack of autophagy. Over time these have slowly gotten clogged with broken parts and waste, rendering them unable to produce collagen. Collagen helps keep skin tight and healthy. Researchers concluded that the slowdown of autophagy “leads to deterioration of dermal integrity and skin fragility.”

In another autophagy and loose skin study, this one from 2018, also looked at the effects of autophagy and loose skin. This study took place at the Department of Dermatology at Incheon St Mary’s Hospital, College of Medicine.  In this study, <fn></fn> scientists examined dermal fibroblasts using transmission electron microscopy. Transmission electron microscopes (TEMs) use a particle beam of electrons to view their specimens. TEMs can magnify objects up to 2 million times.

When scientists observed the process under the TEM, they found that aging fibroblasts experienced more waste and could not keep up with that extra waste being produced because there were only about half as many autophagosomes in older fibroblasts as there were in younger fibroblasts.

What are Autophagosomes?

Autophagosomes are the critical structures in the autophagy process. The inability of the fibroblasts to keep up with and get rid of that extra waste results in skin aging, which leads to wrinkles and loose sagging skin. Autophagy can help rid fibroblasts of this cellular waste and counter these aging effects. 

In summary, then the two fibroblast studies on autophagy and loose skin tell us these things: Fibroblasts make collagen, and collagen prevents loose sagging skin. Autophagy helps cells keep themselves clean and healthy. Aging fibroblasts suffer from increased waste production and less autophagy. When this happens, the fibroblasts cannot produce collagen. Lack of collagen, in turn, leads to aging, sagging skin. Increasing autophagy can help clean fibroblasts and make them able to produce collagen again. These studies then developed the autophagy and loose skin link.

Fasting to Increase Autophagy

avoid intermittent fasting mistakes
Don’t make these intermittent fasting mistakes…

Logically then, to rid yourself of excessive loose skin, you need to increase autophagy. One of the best methods to increase autophagy is fasting.

A literature review published in the November 2018 edition of Ageing Research Review <fn></fn> deemed fasting and caloric restriction to be the most potent “non-genetic autophagy stimulators,” and one that was free of the adverse side effects associated with other methods. The 2018 Incheon St Mary’s Hospital study indicated that calorie reduction could prevent the age-related slowdown of autophagy.

Studies<fn></fn> conducted with mice have shown that fasting and curtailing caloric intake by as much as 40 percent below what their body needed induced autophagy.

Because the study of autophagy is such a new field, scientists aren’t sure exactly how long you need to fast for your body to begin autophagy. Autophagy began in mice about 24 hours into the fast, but the exact timing for humans hasn’t been determined conclusively. Some experts say 16 hours, but more of them believe you should fast for 24 hours or more.  

Dr. Jason Fung, a nephrologist who specializes in research into fasting, believes the autophagy sets in at about the 24-hour point and maxes out at around 32 hours into the fast. He believes that his patients have been helped with their loose skin through autophagy.

Even though scientists are still unsure of exactly when autophagy begins, they know that an extended fast begins to deplete the body of nutrients. When the body fails to obtain the nutrients from the outside, it begins to break down its waste products to create energy itself — and that’s autophagy.

Mehmet Yildiz, an enterprise architect, has used scientific information on fasting and autophagy to make significant lifestyle changes, including now eating only one meal a day, and fasting for at least 16 hours every day. He also exercises and takes cold showers and hot saunas as other ways to stimulate autophagy. He reports that through this regime, he has been able to get rid of excess skin around his abdominal area.

So, now we have established the fasting and autophagy and loose skin link. Fasting leads to more autophagy, which, in turn, leads to tighter and healthier skin.

The connection between autophagy and loose skin is not yet entirely understood, but there are a few potential mechanisms that could explain how autophagy might help with loose skin.

How Autophagy May Help With Loose Skin

  1. Improved cellular health: Autophagy can improve overall cellular health by removing damaged or old cellular components. By doing so, it may promote healthier, more resilient skin cells that can better adapt to changes in the body, such as weight loss or aging.
  2. Collagen synthesis: Collagen is the most abundant protein in our body and plays a significant role in maintaining skin elasticity and structure. Autophagy may help regulate collagen synthesis and degradation, which could contribute to skin elasticity and reduce the appearance of loose skin.
  3. Increased skin cell turnover: Skin cell turnover is the process by which old skin cells are replaced by new ones. Autophagy may help to accelerate this process by clearing away damaged or old cells, which could encourage the growth of new, healthy skin cells that can better maintain skin elasticity.
  4. Reducing inflammation: Autophagy has been suggested to have anti-inflammatory effects. Chronic inflammation can lead to skin damage and affect skin elasticity, leading to loose skin. By reducing inflammation, autophagy could potentially help maintain skin health and elasticity.
  5. Improved nutrient availability: Autophagy can help cells make better use of available nutrients by recycling damaged or unnecessary components. This may improve overall skin health and function, which could contribute to reducing the appearance of loose skin.

A Few Cautions about Fasting and Autophagy

Most experts agree that you shouldn’t regularly fast for more than 36 hours. Healthy people should undertake fasts longer than 36 hours no more than a couple of times a year and then only after talking it over with their doctor.

In general, fasting to induce autophagy is fine and healthy; however, excessive fasting to induce autophagy could overlap with anorexia or other eating disorders. So, if you have a history of eating disorders, tread cautiously with using fasting.

Just as with all the good things of life, moderation and balance are key.  

Other Ways To Promote Autophagy

That being said, fasting is only one part of our plan to rid ourselves of that ugly sagging skin. There are other ways besides fasting to get the benefits of autophagy for decreasing the amount of loose skin.

health benefits of autophagy
Read about the health benefits of autophagy

Exercise to Boost Autophagy

Studies also have shown that exercise also promotes autophagy in peripheral tissues and the brain. Exercise fits into one of two primary types — cardio or strength training. Cardio is good, healthy training for our hearts and can help with losing weight. Strength training helps us lose weight but also enables us to build lean muscle mass.

Lifting weights or other types of resistance training will help us build muscle mass and also will stimulate autophagy.  Resistance training, in combination with intermittent fasting, can stimulate autophagy even more. If done during the weight loss program, this combination of strength training and fasting can help prevent that ugly sagging skin from ever appearing in the first place. 


While there is probably some genetic component to how loose your skin is after weight loss, there is some control that you can also have over trying to reduce the amount of loose skin. There is research on the effects of autophagy and loose skin. Fasting, diet, and exercise are key components for increasing the elasticity of your skin and reducing the amount of loose skin you develop after weight loss.

Find out some of the other health benefits of autophagy here.