Think before you decide to skip your next meal.

People often miss meals because they get busy or are trying to lose weight. But how you skip meals, and the amount you eat at your next meal, can affect your overall health.

The scientific data on skipping meals has been confusing. In some studies, fasting has resulted in measurable metabolic（新陈代谢的） benefits for obese people, and in animal studies, intermittent（间歇的） feeding and fasting reduces the incidence of diabetes and improves certain indicators of cardiovascular health. Even so, several observational studies and short-term experiments have suggested an association between meal skipping and poor health.

In recent months, two new studies may help explain how skipping meals affects health.

The most recent study, published this month in the medical journal Metabolism, looked at what happens when people skip meals but end up eating just as much as they would in a normal day when they finally do sit down to a meal. The study, conducted by diabetes researchers at the National Institute on Aging, involved healthy, normal-weight men and women in their 40s. For two months, the study subjects ate three meals a day. For another eight-week period, they skipped two meals but ate the same number of calories in one evening meal, consumed between 4 p.m. and 8 p.m.

The researchers found that skipping meals during the day and eating one large meal in the evening resulted in potentially risky metabolic changes. The meal skippers had elevated fasting glucose levels and a delayed insulin response -- conditions that, if they persisted long term, could lead to diabetes.

The study was notable because it followed another study earlier this year that found that skipping meals every other day could actually improve a patient's health. In that study, published in March in Free Radical Biology & Medicine, overweight adults with mild asthma ate normal meals one day. This was followed by a day of severely restricted eating, when they ate less than 20 percent of their normal caloric intake, or about 400 or 500 calories a day — the equivalent of about one meal. Nine out of 10 study participants were able to stick to the eating plan.

After following the alternate-day dieting pattern for two months, the dieters lost an average of 8 percent of their body weight, and their asthma-related symptoms also improved. They had lower cholesterol and triglycerides, "striking" reductions in markers of oxidative stress（氧化应激） and increased levels of the antioxidant uric acid. Markers of inflammation were also significantly lower.

The conclusion, say the authors of the more recent meal-skipping study, is that skipping meals as part of a controlled eating plan that results in lower calorie intake can result in better health. However, skipping meals during the day and then overeating at the evening meal results in harmful metabolic changes in the body.