Everything you need to know about the fasting diet

Everything you need to know about the fasting diet

Fasting diets are gaining in popularity as a way to lose weight and still eat whatever you want on occasion. Here’s the skinny on the latest fad diet.

How does intermittent fasting work?

There are different variations of intermittent fasting, but they all have one thing in common: dramatically reducing calorie consumption on certain days or times by skipping meals. One of the more popular intermittent fasting methods is the 5:2 diet. This plan involves eating normal (1200-1800 calories per day) five days a week, while on the remaining two days, reducing calories by 500-600 per day.

Another version of fasting is the alternate-day diet. For this plan, you fast every other day (only consuming 500-600 calories per day) and indulge in whatever you please on non-fasting days.

Will fasting make you lose more weight than a traditional counting calorie diet?

The latest research says no. A recent study published in the journal JAMA Internal Medicine compared alternate-day fasting to a diet of simply cutting daily calorie intake and found that fasting provided no greater benefits than the more traditional weight loss diet.

In the study, 100 participants were assigned to either fast on alternate days, restrict daily calories by 75 percent or follow no diet plan. At the end of the year-long study, researchers found that those in the fasting group were no thinner or healthier than participants who counted and restricted their daily calorie intake. Both groups lost approximately 7 percent of their body weight after six months.

The study also demonstrated that fasting diets may not be sustainable in the long term. Thirty-eight percent of the fasting group dropped out of the plan, compared to 29 percent of the daily calorie-cutting group.

“Any given diet is not a one-size-fits-all plan. Be realistic and consider what is practical and sustainable for your lifestyle when choosing a weight loss plan,” says Diane Gallagher, a registered dietitian and licensed nutritionist at Advocate Christ Medical Center in Oak Lawn, Ill. “Any diet that dramatically reduces calorie intake will help achieve weight loss.”

Gallagher stresses the importance of consuming a healthy balance of calories no matter what diet you choose to follow. “Vegetables, fruits, whole grains and lean protein foods contain the nutrients and energy your body needs to function properly.”

She adds that a combination of both healthy eating and regular exercise can help you achieve your weight loss goals.

Is fasting the best diet for your heart?

While fasting and daily calorie cutting diets can help you lose weight, Dr. Luay Rifai, a cardiologist with the Advocate Heart Institute at Christ Medical Center, says neither method is the winning diet plan for heart health. He says the best diet to help fight heart disease is DASH (Dietary Approaches to Stop Hypertension).

“DASH is the optimal diet to fight heart failure. Not only is it a healthy way to eat, but the diet is easy to follow and maintainable in the long term,” says Dr. Rifai. The DASH eating plan emphasizes high amounts of whole grains, fruits, veggies and protein and cuts back on red meats, saturated fats and sodium.

Currently, the DASH dietary plan is strongly recommended by the American Heart Association and American College of Cardiology for cardiovascular risk prevention.

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  1. Although this article focuses on the effects of fasting on weight loss, research in the area of fasting has shown positive effects on gene expression/epigenetics too. This is an fascinating and widening area of research and we are sure to hear more about it in the future.

    Thanks for all the articles on holistic care, Julie!

  2. “This plan involves eating normal (1200-1800 calories per day) five days a week….”

    On what planet is 1200-1800 “normal”? Just to exist a 150 pound woman burns about 2,000 calories a day! 1500 to 1800 is a reasonable dieting range, but certainly not “normal”. Anything below 1500 is starvation level. Even if a person can sustain that for long enough to lose a decent amount of weight, they’ll gain it all back with interest once they fall off the wagon because metabolism will decrease.

  3. And then there’s this: “…restrict daily calories by 75 percent….”

    What does that even mean??? If a person is consuming a relatively normal 2,000 to 2,500 calorie a day diet, restricting that by 75% would mean that they eat 500 to 650 calories a day! Are you kidding me??? Sure, they’ll lose weight that way. Until they die two months later. Sheesh!

    Please, Advocate, you are embarrassing yourselves publishing this kind of stuff, and certainly not reassuring anyone about the quality of the healthcare you provide.

  4. I fast one day a week. Usually Tuesdays. Have lost 20lbs over 6 months. It works for me, maybe it can work for you. Cravings have been reduced dramatically. AC1’s dropped like a stone. Shalom

  5. Dienne. Restricting by 75% is just alternate days. I did that a couple years ago, following the 5-2 plan. On Mondays and Thursdays I’d aim for 800 calories. It wasn’t actually that hard, egg whites for breakfast, big salad, greens and veggies for lunch, chicken breast and steamed broccoli for dinner, for example. I got the 20 pounds I needed to off just fine.

    Theyre not advocating it, just explaining what some people may be reading elsewhere. And their doctor also said it wasn’t beneficial for weight loss or heart health. You should read it again, perhaps more carefully?

  6. Advocate doesn’t believe that weight management is an important to your health. They recently eliminated all of their Weight Management programs. This article is consistent with their belief you can learn learn all you need to know watching Oprah or Dr Phil.

  7. Freda, not sure what part of Advocate you are a part of, but Advocate Health as a whole is very concerned about weight management. That’s why they offer the Healthe You program and they have a Health and Wellness Center at most hospitals. They also added the Weight Watchers discount program this year which gives associates a huge discount to attend Weight Watchers meetings at a location of their choice and follow the program to help with weight loss. My husband and I joined and are losing slowly but at a steady pace of 1-2 lbs/week. Our location also started a walking club where we walk during our lunch break about a mile a day.

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About the Author

Julie Nakis
Julie Nakis

Julie Nakis, health enews contributor, is manager of public affairs at Advocate Children's Hospital. She earned her BA in communications from the University of Iowa – Go Hawkeyes! In her free time, she enjoys spending time with friends and family, exploring the city and cheering on the Chicago Cubs and Blackhawks.