A Fast Examination of Intermittent Fasting

"On The Run Tour: Beyonce And Jay-Z" - Paris, France - September 12, 2014

Beyonce is reportedly a proponent of the 5:2 fasting regimen.

Many recent studies explore the health benefits of intermittent fasting, which is not a diet, but a dieting pattern. In simple terms, you make a conscious decision to skip certain meals.

That contradicts everything you’ve been told about the importance of eating a healthy and hearty breakfast first thing in the morning. Or eating a light lunch and even lighter dinner with small snacks in between to keep your metabolism on fire. While it contravenes these healthy diet standards we’ve been fed for many years, fasting actually may be the secret for healthy weight loss—and even a method for detoxifying the body for some people.

Evidence does show that these fasting methods can be a safe weight loss strategy if done correctly, but they’re not a superior method to traditional diet and exercise approaches.

Three of the most popular fasting approaches are 24-hour Fasts, 16/8 Fasts and 5:2. The first stems from author Brad Pilon’s book Eat, Stop, Eat. The method is simple enough: don’t eat for two non-consecutive 24-hour periods each week. The second fasting protocol, 16/8, requires a shorter eating window each day, leading to a fasting period of 16 hours per day and squeezing all meals into an eight hour period. The way most people do this is by eating breakfast at noon, and halt eating around 8 or 9 p.m. each day. The third is the 5:2 diet, where you would eat normally five days a week and then only consume 500-600 calories for two nonconsecutive days.

Experts have debated the benefits of intermittent fasting versus six small meals per day, examining the optimal approach for weight loss. Both of these meal-timing trends have their benefits, and one method might not work for everyone. Fasting by nature will help you cut calories, which inevitably leads to weight loss. Experts estimate that these fasting methods can help people cut about 20-25% of overall calorie intake. Success with this dieting pattern largely depends on not binge-eating during normal days, which will cause weight gain.

Hugh Jackman (Getty Images)

Hugh Jackman is a fan of fasting for 16 hours a day. (Getty Images)

Running on empty for a period of time, no matter how big or small, can have serious effects. Many people feel sick when they skip a meal and their energy levels drop. Those who tend to experience low blood sugar when they don’t eat would probably do better with eating six small meals a day.

A 2015 study from researchers at Ohio State University found skipping meals increases blood sugar and insulin spikes. What does this do? It sets the stage for insulin resistance which leads to Type 2 Diabetes. Another 2014 review of research from the University of Illinois-Chicago showed that decreasing daily calorie intake sped fat loss among participants compared with fasting.

Nevertheless, more evidence continues to be brought forth on the potential positive effects of these fasting methods, but this time centered on aging. The University of Southern California recently released a study analyzing intermittent fasting’s effects on mice. Researchers found that periodic fasting could actually help slow aging. More specifically, they identified that cycles of a four-day low-calorie diet which mimics fasting actually reduced visceral belly fat, one of the most dangerous forms of fat on the body. This dieting pattern actually increased the number of progenitor and stem cells the mice’s organs, including the brain, boosting neural regeneration and even improving learning and memory.

When it comes to any intermittent fasting pattern, the question is how does it teach you to eat healthy long-term? Sure with discipline, the weight will come off, but will it stay off? Will you be able to maintain your goal weight once you reach it? I always tell my patients to find what works for them and focus on long-term results instead of a quick fix for weight loss. Instilling healthy habits during a diet period that teach you how to eat well (try the Mediterranean diet- a well-balanced way of eating) and incorporate daily physical activity will be far more beneficial to your overall health and life.

Dr. Samadi is the chairman of urology and chief of robotic surgery at Lenox Hill Hospital and professor of urology at Hofstra North Shore-LIJ School of Medicine. He is a medical correspondent for the Fox News Channel and the chief medical correspondent for AM970 in New York City.

A Fast Examination of Intermittent Fasting