The Facts on Fasting

We’ve all heard it a thousand times: breakfast is the most important meal of the day, and that our skipping meals will wreak havoc on a person’s metabolism and cause weight gain. But does the science support these age-old beliefs?

Intermittent fasting is an eating pattern that cycles between periods of fasting and eating and it is currently one of the most popular health and fitness trends out there. There are a number of different intermittent fasting protocols, so intermittent fasting is essentially an umbrella for a number of different types of eating patterns which consist of significantly reduced intake for no longer than 24 hours.

The Science:

Short-term fasting can actually boost our metabolism, unlike the classic low-calorie diet where 75% of what people lose is fat and 25% is muscle. With alternate-day fasting, weight loss appears to be 90% fat and 10% muscle, according to a study in the January 2013 issue of Metabolism and a study in the November 2009 issue of the American Journal of Clinical Nutrition. However, longer fasts (3 days or more) can suppress metabolism.

Not all fasting diets are the same.
The 5:2 Diet lets you eat a regular Mediterranean style diet five days of the week and then fast on the remaining two days, consuming no more than 500 calories for women to 600 calories for men on fasting days.

Other protocols have you eat 500 calories to 600 calories every other day called Alternate-Day Fasting.

Another approach, called Time-Restricted Eating, requires you to fast for 16 hours of the day and eat only during an eight-hour window. For instance, you might skip breakfast, eat lunch at noon and then finish eating dinner by 8 pm.

And there’s the Eat-Stop-Eat, which involves fasting for 24 hours, once or twice a week, for example by not eating from dinner one day until dinner the next day might be the ideal intermittent fast during the holiday season.

Some people like intermittent fasting because they are relieved of the stress of figuring out what to eat yet are still engaged in the process by learning how to eat healthfully during the normal feeding days with the secret being not to overeat on those days. It works best for people who are not “snackers” but are too busy to eat or like the idea of up and down eating.

Intermittent fasting is not for everyone: Growing children and teenagers, pregnant and nursing women, people with diabetes who take insulin or oral medications and individuals with hypoglycemia (low blood sugar) should not fast.

If you decide to try intermittent fasting, do it correctly. Ensure your calorie intake is high enough to maintain a healthy weight and that the calories you are eating – on fasting and normal eating days – come from nutrient-packed lean proteins, legumes, vegetables, fruit and whole grains. It is temping to head to the snack aisle and stock up on those 100 calories bars but skip the allure and stick to your food values and grab fresh eggs, almonds and greek yogurt.