Eating healthy in the new year just got more confusing
One bit of commonly dispensed dietary advice is to eat small, frequent meals throughout the day. Or, in other words, be a grazer not a glutton. While most of us probably did a little bit of both this December (no judgment, holidays are hell on one’s diet), does a healthier, glutton-free 2016 really mean eating small, frequent meals?
Perhaps not, according to a 2014 study published in the research journal Diabetologia, which examined patients with Type 2 diabetes. For 12 weeks, 54 participants followed both a “grazer’s” diet regimen of six small meals a day, and a “glutton” regimen of two large meals a day—each with the same amount of calories. The study results showed that the two-large-meals diet was better for health, leading to more weight loss, lower fasting blood sugar and better oral glucose insulin sensitivity.
Although small, frequent meals may benefit some, there are some logical reasons why larger, less frequent meals may be a healthy option. From a psychological perspective, eating fewer meals decreases a person’s chances of falling off the wagon and overeating during a given meal. And even when we think we’re eating less, researchers have found that when people self-report, they drastically underestimate the amount of calories they actually consume. Large, nutritious and satiating meals also keep us from getting hungry and craving a snack again in an hour or two.
Biologically, another factor to consider when weighing portion size is the thermic effect of feeding, or the calories that the body burns in order to digest and metabolize a meal. Thermic effect of feeding accounts for roughly 10 percent of a person’s total energy expenditure, although this number varies. Interestingly, the larger the meal the body has to digest, the larger the burn. A 1991 American Journal of Clinical Nutrition study even found that multiple small meals containing the same amount of calories will not create as much of a thermic effect as the same amount of calories consumed in one larger meal. And a 2004 review published in the Journal of the American College of Nutrition concluded that higher protein meals create a larger thermic effect—about 25 percent, compared to both fat and carbohydrates, which give back 5 percent and 5-15 percent respectively.
So what about the growing trend of intermittent fasting? While most diets are about what you eat, intermittent fasting is all about when you eat. Though it’s executed in many different ways, it usually involves eating little or nothing during multiple 12-plus hour periods per week. A mounting body of evidence suggests it may benefit health in several ways.
When a person eats frequently, insulin (an anabolic growth-encouraging hormone), which promotes fat storage, is more often present in the blood stream. But during fasting, the body’s hormones change in a way that increases metabolism and fat burning—especially the dreaded and dangerous belly variety of fat—and may accelerate weight loss.
A 2009 study in The American Journal of Clinical Nutrition showed that intermittent fasting may also improve cholesterol, blood pressure, and triglyceride levels, and a 2007 study in Free Radical Biology & Medicine found it may reduce inflammation and help prevent oxidative damage from free radicals. Short-term fasting has also been shown to increase autophagy, a sort of cellular waste-removal process that may have positive effects with respect to many aspects of health. And many studies, including one published in 1982 in Gerontology, show that intermittently fasted rats age much slower and live much longer than their non-fasted counterparts.
Perhaps the easiest and most popular method of fasting is known as 16/8. Followers of this diet eat only within an eight-hour period (usually skipping breakfast and eating only between, say, noon and 8 p.m.), and fasting the other 16 hours. There is also the 5:2 method, where fasters restrict their calorie intake to approximately 500 or fewer calories on two non-consecutive days per week, and then eat normally on the other five days. Another simple method is known as alternate day fasting, or ADF, and involves fasting and normal eating every other day.
Though there is some evidence that men respond better to intermittent fasting than women, and it is also not recommended for underweight individuals or those with a history of eating disorders, intermittent fasting may be an especially legitimate option to consider if you’ve tried and failed traditional calorie-restriction diets.
PLATE CHANGER A couple large nutritious meals may be healthier than small frequent meals. Oh, and fasting is good for you.