Why Counting Calories May Work Better For Weight Loss Than Intermittent Fasting

A person's weight is intensely personal. But for all that people don't like talking about their weight, methods of weight loss seem to be a perennial hot topic. Exercise trends and fad diets regularly sweep through the public. And, in their wake, many are left wondering if these crazes were worth all the hype. 

Of course, some weight loss ideas stick around longer than others. And one idea that has been popular over the last few years is the concept of intermittent fasting. Johns Hopkins Medicine describes intermittent fasting as weight loss based less on the idea of restricting what you eat and more on the idea of when you eat. Generally this means that an intermittent faster will only eat between certain times of the day or that they will eat very little — Johns Hopkins Medicine specifies one meal — on particular days of the week. The idea behind it is that when you eat less, your body burns the energy it has stored as fat.

It makes sense on the surface. But a new study has thrown doubt on whether the idea of intermittent fasting is really any better than counting calories after all.

Calories are the way we count energy stored in food, according to the British Heart Foundation. When we eat more calories than we need — or we take in more energy than our body is using — the excess energy is stored in fat deposits. Counting calories involves anticipating your body's energy needs and then taking in calories or new energy accordingly. Many people believe that taking in fewer calories than required each day will force their bodies to burn fat, leading to weight loss. But as Harvard Health explains, everyone's body burns calories a little differently. The food the calories come from, a person's gut biome, and their metabolism all play a role in the efficacy of calorie counting.

But it turns out that calorie counting may still be more effective than intermittent fasting. A new 2023 study published in the Journal of the American Heart Association found that the size and frequency of meals, rather than when the meals were eaten, had the most effect on weight loss. It turns out that the study's participants lost the most weight over the long term if they ate fewer calories at their meals and if they ate less frequently during the day. It didn't really matter when their meals were, so long as they reduced their overall food intake.