Calorie restriction is usually associated with weight loss. But a growing body of research suggests that a low-calorie diet may bring a host of other health benefits, even for those not trying to lose pounds.
The latest study, published July 11 in The Lancet Diabetes and Endocrinology, suggests that cutting just 300 calories a day, while maintaining a healthy diet, can significantly improve cholesterol, blood pressure and blood sugar levels, reducing the risk of Having chronic diseases. Like diabetes and heart disease in the future.
Eating Low Calories
The study was small but rigorous. The researchers asked 218 healthy, non-obese adults between the ages of 21 and 50 to undergo a range of medical tests. At the start of the study, most people were eating about 2,400 calories per day, according to self-reported food records.
After baseline testing, approximately 150 participants were placed for a month on a strict diet that reduced regular calories by 25%, while the rest worked as a control group. Subjects in the diet group ate three meals per day at the study center and received dietary advice, while subjects in the control group continued their usual diet and did not receive any counseling. After the first month, the groups were asked to maintain these eating patterns on their own for two years, while having periodic health tests.
People in the calorie-restriction group didn’t follow the directions exactly—only 82% of them completed the full study and, on average, maintained a calorie reduction of about 12% over the two years, instead of 25%. But the researchers found that even this reduction, which translated to about 200-300 fewer calories per day compared to baseline, was associated with “sustained and significant” improvements in cholesterol, blood pressure, blood sugar markers and general metabolic health, all of which correlate with lower risk of chronic disease. Individuals in the control group did not see the same benefits.
Participants in the diet group also lost about the 10% of their body weight on average. But the authors write that the cardiovascular improvements observed in the study were “more and more” than would be expected from this amount of weight loss, suggesting that there is something uniquely beneficial about the modest restriction of calories.
There is a growing movement to move away from counting calories as a measure of health, and instead focus on the overall quality of the diet. One recent study showed, for example, that highly processed meals can affect the body differently than unprocessed meals with a nearly identical nutritional profile, suggesting that it is difficult to assess diet based on numbers alone. There are also likely to be mental health and lifestyle benefits associated with so-called “intuitive eating” versus strict calorie counting.
But at the same time, quite a few studies suggest that moderation in calories may be associated with health benefits beyond weight loss. A 2016 study, for example, found that reducing calories was associated with improved mood, sexual function, and general health. Studies in rhesus monkeys have found links between calorie restriction and longevity, and intermittent fasting — alternating between calorie restriction and regular eating — has been linked to improved weight loss and a reduced risk of the chronic disease.
Severe calorie restriction is dangerous, and any substantial change in diet should be discussed with an expert. But for most people, it’s relatively easy to cut 200 or 300 calories per day without drastic change, or any obsessive control.
Federal data also shows that snacks make up nearly a quarter of the calories Americans consume each day. Since snack foods tend to be processed and filled with additives like salt and sugar, eliminating or improving the quality of snacks is a good goal to modestly cut calories.