For the last time, forget juice cleanses and detox diets. They’re fluffy nonsense words. While there’s probably nothing wrong with drinking your weight in liquid kale, it won’t flush out toxins any faster than if you were eating, you know, actual food.
The good news: There's a little-known way your body does cleanse itself, and it’s a process that you can control.
All you need to do is practice a little self-cannibalism.
Yes, you can actually train your body to eat itself—and believe it or not, you want it to.
It's a natural process called autophagy (literally “self-eating”), and it’s the body’s system of cleaning house: Your cells create membranes that hunt out scraps of dead, diseased, or worn-out cells; gobble them up; strip ’em for parts; and use the resulting molecules for energy or to make new cell parts.
“Think of it as our body’s innate recycling program,” says Colin Champ, M.D., a board-certified radiation oncologist, assistant professor at the University of Pittsburgh Medical Center, and author of Misguided Medicine. “Autophagy makes us more efficient machines to get rid of faulty parts, stop cancerous growths, and stop metabolic dysfunction like obesity and diabetes.”
There’s also evidence that the process plays a hand in controlling inflammation and immunity. When scientists engineer rats that are incapable of autophagy, they’re fatter, sleepier, and have higher cholesterol and impaired brains. Loss of autophagy in pro-opiomelanocortin neurons perturbs axon growth and causes metabolic dysregulation. Coupé B, Ishii Y, Dietrich MO. Cell metabolism, 2012, Jan.;15(2):1932-7420.
To sum it up, autophagy is key to slowing the aging process. Autophagy and aging: the importance of maintaining "clean" cells. Cuervo AM, Bergamini E, Brunk UT. Autophagy, 2005, Oct.;1(3):1554-8627. Autophagy maintains stemness by preventing senescence. García-Prat L, Martínez-Vicente M, Perdiguero E. Nature, 2016, Jan.;529(7584):1476-4687. And you can learn how to do it better.
3 Ways to Self-Destruct
"So how do I eat myself?” is a question you probably haven’t asked before, but we’re about to tell you. First of all, autophagy is a response to stress, so you’re actually going to want to put your body through stress in order to drum up a little extra auto-cannibalism. (We know this article keeps getting weirder, but trust us.)
As is often the case, short-term discomfort can bring long-term benefits. Here are three main ways to boost your autophagy.
In case the sweating, grunting, and post-workout pain didn’t tip you off, here’s a reminder: Exercise puts stress on the body. Working out actually damages your muscles, causing tiny microscopic tears that the body then rushes to heal, making the muscles stronger and more resistant to any further “damage” you might put it through.
Regular exercise is the most popular way that people unintentionally help their body to cleanse. (So there’s actually something to that fresh, renewed feeling you get after working out.)
Regular exercise is the most popular way that people unintentionally help their body to cleanse.
One study looked at autophagosomes, structures that form around the pieces of cells that the body has decided to recycle. Exercise-induced BCL2-regulated autophagy is required for muscle glucose homeostasis. He C, Bassik MC, Moresi V. Nature, 2012, Jan.;481(7382):1476-4687. After engineering mice to have glowing green autophagosomes (as one does), scientists found that the rate at which the mice were healthily demolishing their own cells drastically increased after they ran for 30 minutes on a treadmill. The rate continued increasing until they’d been running for 80 minutes. (This actually inspired the study’s lead scientist to buy a treadmill.)
What about humans? “Determining the level of exercise needed to stimulate autophagy, and the extent to which the process is upregulated, are hard questions to answer at the moment,” says Daniel Klionsky, Ph.D., a cellular biologist at the University of Michigan who specializes in autophagy. “(But) clearly exercise has many benefits, aside from the possible role of autophagy, so that is probably a good bet in general.” And if you like tough workouts, all the better: Champ recommends relatively intense exercise for maximum benefits.
Ironically for folks who "cleanse" by drinking juice, the act of eating actually works against autophagy. Skipping meals, it turns out, is another stressful act that the body may not immediately love but ultimately benefits from.
In fact, research has shown there are loads of benefits to an occasional fast, and some of them—like lower risks of diabetes and heart disease—might be attributed to autophagy. Effect of intermittent fasting and refeeding on insulin action in healthy men. Halberg N, Henriksen M, Söderhamn N. Journal of applied physiology (Bethesda, Md. : 1985), 2005, Jul.;99(6):8750-7587. Usefulness of routine periodic fasting to lower risk of coronary artery disease in patients undergoing coronary angiography. Horne BD, May HT, Anderson JL. The American journal of cardiology, 2008, Jul.;102(7):0002-9149.
It’s also pretty remarkable how much research has focused specifically on the way fasting promotes autophagy in the brain, suggesting that it could be an effective way to lower the risk of neurodegenerative diseases like Alzheimer’s and Parkinson’s. Short-term fasting induces profound neuronal autophagy. Alirezaei M, Kemball CC, Flynn CT. Autophagy, 2010, Aug.;6(6):1554-8635. Disruption of neuronal autophagy by infected microglia results in neurodegeneration. Alirezaei M, Kiosses WB, Flynn CT. PloS one, 2008, Aug.;3(8):1932-6203. Autophagic neuron death. Uchiyama Y, Koike M, Shibata M. Methods in enzymology, 2009, Apr.;453():1557-7988. Loss of autophagy in pro-opiomelanocortin neurons perturbs axon growth and causes metabolic dysregulation. Coupé B, Ishii Y, Dietrich MO. Cell metabolism, 2012, Jan.;15(2):1932-7420.
In some studies, intermittent fasting was shown to improve cognitive function, brain structure, and neuroplasticity, which may help the brain to learn more easily. Chronic intermittent fasting improves cognitive functions and brain structures in mice. Li L, Wang Z, Zuo Z. PloS one, 2013, Jun.;8(6):1932-6203. Meal size and frequency affect neuronal plasticity and vulnerability to disease: cellular and molecular mechanisms. Mattson MP, Duan W, Guo Z. Journal of neurochemistry, 2003, Feb.;84(3):0022-3042. Cardioprotective effect of intermittent fasting is associated with an elevation of adiponectin levels in rats. Wan R, Ahmet I, Brown M. The Journal of nutritional biochemistry, 2009, May.;21(5):1873-4847. Late-onset intermittent fasting dietary restriction as a potential intervention to retard age-associated brain function impairments in male rats. Singh R, Lakhanpal D, Kumar S. Age (Dordrecht, Netherlands), 2011, Aug.;34(4):1574-4647. That said, it wasn’t totally clear if autophagy was the cause; plus, those studies were done on rodents. People aren’t rodents, and we can’t always assume the benefits will be the same for us humans.
In any case, here's our quick guide to intermittent fasting. Practitioners usually forego food for anywhere from 12 to 36 hours at a time, making sure to drink plenty of water. (You might also want to limit activity to gentle yoga or stretching.)
3. Lower Your Carb Intake
While Champ fasts for 18 hours per day a couple times per week, he recognizes that for the average Joe, that can be a tough routine to follow. Simply forgoing food on the odd occasion seems to work (one study showed a lower risk of heart disease from just one fast day per month), but there’s another way to get similar benefits without giving up your favorite rib eye (though you’ll probably need to quit candy).
It’s called ketosis, and it’s an increasingly popular diet among bodybuilders and anyone seeking a longer lifespan. The idea is to reduce carbohydrates to such low levels that the body has no choice but to use fat as a fuel source instead.
Ketosis is like an autophagy hack. You get a lot of the same metabolic changes and benefits of fasting without actually fasting.
Ketosis can help people lose body fat while retaining muscle, and there’s some evidence that it helps the body fight cancerous tumors, lowers the risk of diabetes, and protects against some brain disorders, particularly epilepsy. (Research showed that more than half of children with epilepsy who go on the diet have at least a 50 percent reduction in seizures.)
“Ketosis is like an autophagy hack,” Champ says. “You get a lot of the same metabolic changes and benefits of fasting without actually fasting.”
Keto diets are super high fat: Between 60 and 70 percent of one’s overall calories should come from fat. (Lots of steak, bacon, and peanut butter shakes are a definite bonus for the keto crowd.) Protein makes up 20 to 30 percent of calories, while carbs are kept below 50 grams per day.
But if staying in ketosis sounds even harder than not eating at all, take heart. Similar benefits have been noted in people following a diet in which carbs didn’t exceed 30 percent of their overall calories, Champ says. Effect of dietary macronutrient composition on AMPK and SIRT1 expression and activity in human skeletal muscle. Draznin B, Wang C, Adochio R. Hormone and metabolic research = Hormon- und Stoffwechselforschung = Hormones et métabolisme, 2012, Jun.;44(9):1439-4286.
Is There an Easier Way?
Nah. But there’s a lot money to be made if researchers can distill the benefits of autophagy into a pill, so you can be sure they’re trying.
“Of course people are looking for ways to induce autophagy through chemicals, because it would be easier than dieting,” Klionsky says, but he cautions that we’re a long way off.
Champ notes that anti-epileptic drugs are being developed that mimic the effects of ketosis. If they become available to the broader public, there’s a chance we’ll be able to pop a pill that cranks up autophagy with practically no effort.
Still, don't get your hopes up: “There are so many metabolic changes that take place during ketosis that mimicking all of them with a pill might not be possible,” Champ says. “The bodily stress that comes with entering ketosis might be necessary for the benefits.”
Just remember: You don’t have to fast, stay in ketosis, or exercise intensely all day every day to experience these benefits—even a few hours of any of these activities can help.
There’s a pretty strong case to be made that stress and self-destruction lengthens your lifespan. “It’s our ancestral and evolutionary response to dealing with feast and famine in times of stress,” Champ says. “Since a lot of these things would kill us, like starvation and exercise, it only makes sense that after millions of years we adapted those mechanisms to make them positive.”
Klionsky notes that there’s still a lot we don’t know about the process, and it’s too early to definitively say that autophagy will cure cancer, make you a genius, and stave off aging for good.
There’s a pretty strong case to be made that stress and self-destruction lengthens your lifespan.
“One fundamental problem is that it is still difficult to monitor autophagy in a living organism, especially a human,” he says.
The bottom line: Regular exercise and occasional carbohydrate restriction carry mountains of benefits in addition to their likely impact on autophagy. The best that could happen is a stronger, leaner, and cleaner body. That’s our kind of detox.