Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In

Become a Member

Get access to more than 30 brands, premium video, exclusive content, events, mapping, and more.

Already have an account? Sign In



How Intermittent Fasting Resets Your System – And How To Do It Right

Science shows intermittent fasting can offer health benefits big and small. It can even reset some of your body's critical systems.

Heading out the door? Read this article on the new Outside+ app available now on iOS devices for members! Download the app.

For many decades, scientists have recognized that periods of fasting appear to improve resistance to disease and enhance longevity. Intermittent fasting, when done properly, can push the reset button on your whole body.

Here’s what you need to know about this time-restricted way of eating and how to do it right.

What is intermittent fasting?

In general, intermittent fasting involves cycling between periods of eating and relatively brief periods of fasting. This practice of restricting or eliminating food in a specific pattern capitalizes on the body’s natural ability to detox. It happens via a process known as autophagy – the body’s protective housekeeping mechanism – damaged cells, proteins and debris are destroyed and recycled, restoring optimal functioning of cells and delaying the effects of aging.

Simply put, intermittent fasting resets your body’s cellular turnover, keeping every system running at its best.

What the science shows

Autophagy is just one of the well-researched perks of IF. A number of studies link intermittent fasting with everything from weight loss and immune support to disease prevention and longer lifespan. Here are some highlights of its benefits.

Improved immunity

Studies show fasting for three days creates significant shifts in the body’s process of making new white blood cells; when you stop eating, worn out and damaged immune cells are recycled as the body tries to conserve energy. When you start eating again, the immune system is triggered to produce new white blood cells. Some research suggests you can reap the same benefits with shorter periods of fasting, like the typical 16-hours used in intermittent fasting.,

Reduced body fat

Modified fasting plans can promote weight loss, improve metabolic health and preserve lean mass. In one study, overweight adults who consumed 20 percent of their normal calorie intake on alternate days lost 8 percent of their body weight over an eight-week period. In another review, intermittent fasting resulted as much as a 16 percent decrease in body fat over a three- to 12-week period; plus, intermittent fasting was more effective at retaining lean mass than daily caloric restriction.

Cognitive health

When you don’t eat for 10 to 16 hours, the body turns to its fat stores for energy. That, in turn, releases fatty acids called ketones into the bloodstream. Those ketones protect memory and learning, and slow disease processes in the brain. Research points to the neuroprotective effects of intermittent fasting on brain functions and structures, and one study suggests fasting from dawn to sunset for 30 consecutive days can benefit cognitive and neuropsychiatric diseases.

Resistance to disease

Periods of fasting reduce the release of pro-inflammatory cells called monocytes, balancing the body’s inflammatory responses and protecting against chronic inflammation, which is linked to an increased risk for degenerative diseases. Studies suggest intermittent fasting can improve resistance to cancer, heart disease, diabetes, neurological disorders and other diseases.,

Enhanced longevity

Restricting calories in a way that doesn’t compromise overall health protects against oxidative stress, enhances DNA repair and potentially increases healthy lifespan. Human trials involve short-term interventions, so long-term data is lacking. But most point to the beneficial effects of calorie restriction on aging and health, and in one study of patients who underwent cardiac catheterizations, those who fasted regularly had almost twice the rate of survival as non-fasters.

How to do intermittent fasting right

Ready to reset your body with intermittent fasting? The IF plan itself is simple, with no complex meal manipulations, food substitutions or rules; you just don’t eat for a set number of hours. You can approach the eating and fasting cycle in a variety of ways.

One of the most popular, and easiest to follow, is time-restricted eating. This limits your food intake to a set number of hours. So, for example, on the typical eight-hour plan, you’d stop eating at 8 pm and have your next meal at noon the following day. Some plans also use alternate-day fasting – eating normally for one day, then fasting the next – or two-day fasting, followed by five days of eating normally.

Intermittent fasting doesn’t dictate what kinds of foods you eat, so it’s one of the most flexible plans you’ll find. It’s able to accommodate a variety of diets. You can try IF whether you’re trying vegan, gluten-free, Keto and other diet options. But, because there are no restrictions on foods or calories, it’s tempting to binge, especially if you haven’t eaten for 16 hours or more. If you try to game the system – scarfing down cheese puffs and ice cream in your eight-hour eating window, for example – you won’t get the results you’re looking for.

The best approach for IF is to start with a shorter fasting time, like 8 pm to 8 am. Then, gradually extend the time between your last meal of the night and your first meal of the next day. You’ll also want to drink plenty of water to avoid dehydration during your fasting hours. And stick to a clean, whole-foods diet with lean protein, healthy fats and abundant vegetables to be sure you’re getting plenty of nutrients – and maximizing the benefits.

Want to learn more about intermittent fasting and its plentiful potential? Keep reading:

Show Your Liver Some Love: A Clean Eating Webinar

Join Clean Eating dietitians Tiffani Bachus and Erin Macdonald for an exclusive webinar all about liver health and wellness.