Men's caloric needs peak at about age 25 and then decline over the years. If you're a 30-year-old man on the same diet that you had five years ago, you might not notice these body changes until you begin to gain weight. The U.S. Department of Agriculture reports that many American diets reflect this calorie imbalance, as evidenced by the rise in obesity. The ideal caloric intake equals your caloric output through activity. The USDA estimates this average caloric need for men 30 years of age at 2,600 calories per day.
Body Mass Index
To learn whether you are overachieving in the area of calorie consumption, calculate your body mass index, or BMI. Record your height in inches and your weight in pounds. Multiply your weight by a factor of 703. Divide the result by your height, and divide that result by your height again. This is your BMI, which is in the healthy range at 18.5 to 25, and underweight or overweight below or above those figures. The National Institutes of Health note that bodybuilders may need a medical assessment of body mass and weight.
Food label information will help you calculate your current average caloric intake. Note the calories per suggested serving of the foods that you eat in a day, and increase that amount if you typically eat more. Weight maintenance at this level of consumption means that you are meeting your personal caloric needs without any excess or shortage. Weight gain may be due to a combination of your body's decreased calorie needs and your diet's calorie surplus.
If you're gaining weight at your current caloric level, you'll need to alter your diet, your exercise plan, or both. In order to stay at a healthy weight for your height and age, you need to expend all the calories that you get from food. Sedentary men may only be able to burn 2,400 calories a day. Thirty-year-old men who play high-intensity sports may need as many as 3,000 calories per day to sustain their weight. To reach caloric balance on an average diet of 2,600 calories, the U.S. Department of Health and Human Services advises 150 minutes of moderate exercise per week in addition to normal daily activities.
Gaining a few pounds may not seem like a big deal at age 30. Failing to lose those pounds, however, and adding more to your weight through the same diet and exercise habits can shorten your life. According to the Office of the Surgeon General, men with a BMI of 25 to 30 or greater have an increased risk for potentially fatal heart disease, type 2 diabetes and prostate cancer.
- U.S. Department of Agriculture; Dietary Guidelines for Americans; December 2010
- National Institutes of Health; Body Mass Index; May 2011
- U.S. Department of Health and Human Services; Physical Activity Guidelines for Americans; 2008
- Office of the Surgeon General; Overweight Consequences; January 2007