You may have heard the term “autophagy” before, maybe in the context of intermittent fasting, sleep, or exercise. But what is autophagy, really? And how do we make sure our body is performing this important process? Read on to have all your autophagy questions answered.
What is autophagy?
In terms of formal, scientific definitions, a 2019 study published in the journal Nutrients describes autophagy as “an internal process that aids in the lysosomal degradation and removal of old and unwanted cellular molecules, including proteins, ribosomes, lipid droplets, and other organelles, thereby maintaining cellular homeostasis and survival under metabolic stress.”
The short definition is that “autophagy is the housekeeping of the cells,” says Ruvini Wijetilaka, M.D.., a board-certified internal medicine physician with an interest in nutrition and wellness at Parsley Health in New York City. Basically, autophagy recycles damaged proteins and organelles, which are like the organs of our cells. Autophagy is happening naturally in our bodies all the time, but certain lifestyle factors can influence how well it’s performing.
Autophagy is important because when your cells clean house, they take a break from dividing, and that’s a good thing. “You don’t want your cells always dividing because that will create free radicals,” says Dr. Wijetilaka. And as many of us know already, too many free radicals are associated with cellular damage and a wide range of diseases. Autophagy is kind of like eating leftovers; without eating the food you’ve already made that’s sitting in your fridge, the fridge will overflow and the food will go bad.
What are the benefits of autophagy?
Autophagy is important throughout our entire life, but it’s especially critical as we age. As Dr. Wijetilaka explains, “As we get older we lose this process and proteins and debris start to build up, which can cause problems.” Studies have linked a buildup of proteins to diseases like Alzheimer’s and Parkinson’s as well as other memory and movement disorders. “Another autophagy-related issue that a lot of people have is osteoarthritis,” she adds. Indeed, the authors of a 2018 study published in Science Translational Medicine concluded that “autophagy-related genes were reduced in human chondrocytes from patients with osteoarthritis.”
Overall, Dr. Wijetilaka says autophagy functions to prevent disease and promote overall health and balance. “Everything that it does helps create a checks and balances system in your body,” she explains.
Unfortunately, autophagy isn’t always happening the way it should. “Factors like lack of sleep, lack of exercise, and an unhealthy diet can disrupt the process and put our health at risk,” says Dr. Wijetilaka.
How does chronic stress affect autophagy?
Therefore, the best way to support autophagy is to avoid the lifestyle factors that hinder it, starting with chronic stress. “A little bit of stress is okay, but if you’re constantly stressed it can prevent your body from cleaning house and taking care of those old and dead proteins in your body,” says Dr. Wijetilaka. Chronic stress isn’t just linked to autophagy, either. In fact, researchers estimate that workplace stress alone is responsible for over $190 billion dollars of U.S. healthcare costs.
To combat chronic stress, Dr. Wijetilaka commonly recommends three action steps to her patients. First, “find some sort of movement that you enjoy,” she says. It could be anything from dancing or tennis to running or gardening. Next, adopt a meditation practice, even if it’s just for 5 or 10 minutes a day. And finally, try your best to foster a sense of community. “Having good friends and a good support system around you is critical. Loneliness is an epidemic and it’s a risk factor for poor health,” says Dr. Wijetilaka.
Once you’ve tackled chronic stress, maintaining a healthy lifestyle is a great way to stimulate autophagy and thus, overall long-term health.
How to induce autophagy
When it comes to healthy autophagy, a great place to start is with sleep. As they write in a 2019 study published in Sleep Medicine, “…REM sleep maintains neuronal integrity and house-keeping functions of the brain.” According to the study, it does this by modulating noradrenaline levels, which is intricately involved in stimulating autophagy.. At Parsley Health, Dr. Wijetilaka recommends that all her patients get 7 to 8 hours of high-quality, restorative sleep a night.
Exercise, particularly HIIT workouts, can also help support autophagy as well as infrared sauna and cryotherapy. “Anything that puts your body under a type of healthy stress,” says Dr. Wijetilaka. Technically, autophagy is an evolutionary adaptation that was designed to help humans survive times of famine, intense exercise, and extreme heat and cold. These days, we live pretty comfortable lives, which means fewer opportunities to induce autophagy. That’s where healthy stress comes in; we want to create scenarios where autophagy can be supported and stimulated.
How does intermittent fasting stimulate autophagy?
A healthy diet is also key to making sure our body has the energy to repair itself. “Gluten, dairy, and processed foods can all contribute to lack of autophagy,” says Dr. Wijetilaka. Meanwhile, a healthy diet full of real, whole foods can also help stimulate autophagy — especially fat, which is why you may have seen the ketogenic diet advertised as a great way to support cellular cleanup. “It’s suspected that fat stimulates autophagy instead of protein and carbs,” she continues. (You can read more about the ketogenic diet here.)
And when it comes to autophagy, when you eat might be even more important than what you eat because intermittent fasting is another great way to stimulate this process. “If you’re constantly feeding your body, it prevents autophagy,” says Dr. Wijetilaka.
The mechanism by which this happens is as interesting as it is complicated. According to Dr. Wijetilaka, fasting stimulates a pathway called AMPK, which inhibits MTOR activity, which then stimulates autophagy. “MTOR is the pathway in the body that tells the cells to divide and grow, and it’s activated when you are well-fed,” she says. So, it makes sense that you have to actually inhibit MTOR activity in order to stimulate autophagy. As Dr. Wijetilaka explains it: “When you fast, it tells the body to stop dividing your cells and instead eat up this debris that we’ve already made.” There’s no clear cut answer on exactly how long to fast for autophagy, but many experts recommend starting with a 12-hour window between dinner and breakfast the next day and increasing from there.
Fasting may even explain why sleep is so good for autophagy. As they wrote on the Cedars Sinai Health Blog, “Autophagy happens while we’re sleeping — because that’s when we’re fasting.”
Can supplements stimulate autophagy?
On top of healthy lifestyle choices, certain supplements can help support autophagy in the body.
According to Dr. Wijetilaka, green tea and hesperiden, which is a type of orange extract, are two worth mentioning. As the authors of a 2019 study wrote, “green tea polyphenols induce autophagy, thereby revitalizing the overall health of the organism consuming it.”
As for Hesperiden, a 2014 study published in the European Journal of Cancer concluded that the orange extract simulated autophagic markers and prevented the accumulation of proteins.
Will living a healthy lifestyle guarantee healthy autophagy?
You may have noticed that sleeping well, eating well, and exercising are not just the key to healthy autophagy — they’re the key to general good overall health as well. This is not a coincidence; the two are intricately related.
In reality, autophagy isn’t something most people need to be thinking about all the time. Instead, we should be focusing on our everyday lifestyle choices like sleeping 8 hours a night, eating plenty of leafy greens, and moving our bodies. Autophagy is something that will happen naturally in the background as long as we’re taking care of ourselves. “It’s a good reminder that as long as you’re living a life that’s in balance, everything else falls into place,” says Dr. Wijetilaka.