How Often Should You Eat?
The Theory: Nutrition experts tend to recommend eating 3 balanced meals (350 to 600 calories each) and 1 to 3 snacks per day (between 150 and 200 calories each). The calories for each meal and snack depend on a variety of factors including, height, weight, age, gender and activity level. The philosophy is to make sure you don't go longer than 5 hours or so without eating. After going without food for a prolonged period of time, folks tend to become ravenous and their decision-making skills plummet. They end up choosing any food they can find, including fast food or high-calorie treats.
Pros: Having a small, healthy snack between meals (like cut veggies and hummus or half a PB&J on whole-wheat bread) can curb hunger until the next meal and enable people to make sensible food choices.
Cons: One big issue I've seen with clients is that they tend to overdose on snacks: Instead of having 150 to 200 calories, they end up munching on closer to 400 to 500. In addition, foods chosen for snacks should provide good-for-you nutrients the body deserves; higher calorie snacks (like cookies, cakes, sugary drinks) tend to be empty of nutritional value.
The Theory: The other school of thought is to eat one or two larger meals a day, which gives people less of an opportunity to graze on extra calories throughout the day.
Pros: A recent study presented at the 2013 American Diabetes Association conference found that, compared with folks who ate 6 smaller meals daily, study participants who ate 2 large meals per day (breakfast and lunch) lost more weight, even though both groups consumed the same number of calories. All of the subjects in the study had type 2 diabetes.
Cons: It should be noted that this study only had 54 participants, which is a very small sample size. In addition, experts not involved in this study have commented that skipping dinner isn't feasible since it's the one meal most folks have time for. Furthermore, skipping meals isn’t a good idea for diabetics, as the amount of glucose (aka sugar) they get from food should be evenly distributed throughout the day.
Another downside to this way of eating is that most people may not be able to take in all of their essential nutrients in one or two sittings, especially since several vitamins and minerals negate each other in the body. (For example, iron is less likely to be absorbed when high amounts of calcium are around.)
Studies have also shown negative consequences of eating larger, less frequent meals. One 2007 study published in the journal Metabolism looked at folks who ate one big meal as opposed to 3. They tended to eat as many calories in that one meal as in 3 smaller meals. And researchers found that eating one meal resulted in potentially dangerous metabolic consequences. Folks who skipped meals had higher blood sugar levels and a delayed insulin response—these are two conditions that can lead to diabetes if they continue over a long period of time.
Finally, a 2010 study published in the British Journal of Nutrition found that when subjects ate 3 meals and 3 snacks versus 3 meals per day (while eating the same amount of calories), the rate of weight loss was not greater with either type of eating pattern.
Bottom Line: Stick to eating smaller, frequent meals as opposed to eating one or two larger ones. However, that doesn’t give you free rein to eat whatever you want. Calories still need to be kept in check and food choices should be well balanced from all the food groups.
Toby Amidor, MS, RD, CDN, is a registered dietitian and consultant who specializes in food safety and culinary nutrition. See Toby's full bio »