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3 Reasons to Try Intermittent Fasting

Want to lose weight but don’t know if intermittent fasting is right for you? Here are three ways to tell.

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When Elsy Alvarado, age 55, stepped on a scale and saw a number that was 10 pounds heavier than her usual weight, she thought there was something wrong with the scale. Then she realized it was working just fine. “It was a reality check,” she says. She decided to take action. “I heard about intermittent fasting from a very good friend,” she goes on. “I noticed that he had clearly lost a ton of weight. I asked him, ‘What are you doing?’ and he told me—he was doing intermittent fasting.” Alvarado did a lot of research into fasting—and was intrigued. She wondered, was this right for her?

If you are tempted to try fasting, talk to your doctor first, and see if these points apply to you.

You hate conventional diets.

“Fasting diets are a viable option for people who want to lose weight, especially for people who do not want to count calories or find other diets to be fatiguing,” says Krista Varady, associate professor of nutrition in the University of Illinois/Chicago College of Applied Health Sciences, who has studied fasting and weight loss for years.

This was exactly why Alvarado was interested. “I am a terrible dieter,” she admits. “As soon as I say I am on a diet I’m hungry all the time.”

She wanted to try the type of intermittent fasting that involves not eating every day for 12 to 16 hours, starting in the evening after dinner and not eating until the following morning. Since most of the fasting time would happen while she was asleep, it seemed easy to do. For the rest of the day, eating is unrestricted, though Alvarado usually chose healthy foods.

You need to lose weight.

Are you a lot or even a little overweight? According to the CDC, obesity is still on the rise—and this means more people will suffer from related illnesses such as stroke, heart disease, diabetes and some types of cancer.

But even being overweight can have negative health effects. Alvarado weighed 109 most of her adult life, and at a petite 5-foot, 1 inch tall, this was a good weight for her. After learning she’d gained ten pounds without noticing, she feared more weight gain in the future.

In one of her studies, Varady looked at obese adults who fasted every day from 6 p.m. to 10 a.m. After 12 weeks, study participants lost about 3 percent of their weight and their blood pressure was reduced. Without even thinking about calories, they had consumed about 350 fewer per day.

Another kind of fasting involves eating one moderate meal a day on several days a week. And yet another type involves eating only between the hours of 1 p.m. and 5 p.m. or 1 p.m. and 7 p.m. All of these of fasting routines lead to weight loss, Varady found. Side effects such as headaches, are mild and temporary.

Alvarado fasted between 7 p.m. to 7 a.m., and sometimes even longer. “When I went more than 14 hours it didn’t feel right,” she says. She also increased her exercise, doing more yoga and hiking.

It worked—she lost about 18 pounds in four months.

You’re ready for healthier eating habits.

In addition to losing weight and possibly lowering blood pressure, intermittent fasting may bring other long-term health benefits, according to Johns Hopkins neuroscientist Mark Mattson, Ph.D. In reviewing animal studies, he points out that intermittent fasting can lead to better glucose regulation, increased resistance to stress, suppressing inflammation and improved brain function.

Though it may not be more effective than other weight-loss diets, intermittent fasting can be more enjoyable, which makes it easier to do. “What I love about it is eating what I like to eat,” says Alvarado. “I don’t have cravings at night and I am full of energy in the morning.”