Your guide to intermittent fasting

You may opt for one fad diet or another — paleo, keto, alkaline or carb cycling — but none of them takes into account an essential truth about your body: It uses calories, fat, carbs and glucose differently at different times of the day.

Studies show that eating the same amount of calories early or later in the day produces two very different results. Frontload your food intake so you get 80 percent of your calories before 1 or 2 p.m., and you can lose weight. Eat more than 20 percent of your calories in the evening, and you’ll have trouble losing weight and may even pack it on.

Your body is made to consume food while the sun is shining and to not consume food while it’s dark. That aligns with the healthy choice of having at least 12 hours between dinner and breakfast.

HOW TO SCHEDULE YOUR EATING

One option that can help you cut out your late-night snacking or dinner-then-right-to-bed syndrome is to consider intermittent-fasting. You eat so that there’s a chunk of hours in the day when you don’t consume anything but water, coffee or tea.

It can improve your nutrition, superpower your energy level, help you sleep, reduce your risk for Type 2 diabetes and promote weight loss and improved HDL and LDL cholesterol levels. (That is, if you don’t overeat on non-fasting days.)

Mark Mattson, the senior investigator for the National Institute on Aging, says, “There is considerable similarity between how cells respond to the stress of exercise and how cells respond to intermittent fasting.” True, most studies have been done on lab animals, but there’s mounting evidence that intermittent fasting is beneficial.

One study of overweight adults with asthma had participants eat 20 percent of their regular caloric intake on alternate days for eight weeks. The results: They lost 8 percent of their initial body weight, reduced levels of markers of oxidative stress and inflammation and saw asthma symptoms and quality of life improve.

Multiple studies indicate intermittent fasting may help stimulate production of adult stem cells, particularly in the intestines and skeletal muscles, which are essential to counter the decline in bodily functions associated with aging.

So what are your choices?

In “What to Eat When,” Dr. Mike Roizen’s book with Dr. Michael Crupain, the “When Way” guidelines are:

1. Fast each night with at least 12 hours between dinner and breakfast. Want more benefits? Extend that to 14 hours, and then 18. This causes your body to burn up most circulating glucose and stabilizes insulin levels. Then your body burns stored fat.

2. Breakfast and/or lunch should contain lean and plant-based protein (think whole grains, legumes, salmon) and fats (think healthy fats in salmon, or use extra-virgin olive oil with grains and veggies). Your body is naturally more insulin-resistant at night. Avoid simple carbs after mid-day. Dinner should be plant-heavy (salad and other green, leafy veggies) and calorie-light (about 400 calories).

3. The Longevity Institute at USC says you can superpower your health and boost weight loss by reducing your calorie intake to 1,000 for one day, 750 for four days. Then resume eating the When Way.

Other patterns for intermittent fasting

You may want to try eating for eight hours — say, noon to 8 p.m. daily — and fasting for 16. Or try the two-five routine, in which you restrict your intake to 500 calories a day twice a week. Then, five days you eat a healthy, full complement of calories. And then there’s the Warrior Plan: eating during four hours a day and fasting for the remaining 20.

Mehmet Oz, M.D., is host of “The Dr. Oz Show,” and Mike Roizen, M.D., is Chief Wellness Officer and Chair of Wellness Institute at Cleveland Clinic. Email questions to youdocsdaily@sharecare.com.