Average Increase of Weight in Adults

Nearly 40 percent of Americans had obesity between 2015 and 2016, according to the Centers for Disease Prevention and Control (CDC). While it's difficult to determine the average weight gain per year after 30, experts estimate that most adults ​gain around 0.6 to 1.7 pounds annually​. It may not seem like much, but this small, consistent weight gain can contribute to obesity and affect your health in the long run.

Your body weight is directly related to your metabolism and lifestyle habits. As you age, your metabolic rate decreases. This means that you'll burn fewer calories, which in turn, may contribute to weight gain.

As the American Institute for Cancer Research notes, ​age-related weight gain​ is due to a decrease in muscle mass, reduced physical activity and metabolic slowdown. People tend to be less active as they get older. Many of them have a busy lifestyle and prioritize comfort.

​Read more:​ The Metabolism Whisperer Shares Secrets for Burning More Calories

Think about it: Would you prefer to go to work by car or jump on the bike and take a morning ride to your office? Probably the first option.

When you were younger, though, it was a lot easier to find time for a ride and stay active throughout the day. This decrease in physical activity leads to a ​gradual reduction in lean mass​, which in turn, slows down your metabolism and increases body weight.

According to the Harvard School of Public Health, ​being moderately active for at least 30 minutes a day​ can lower the risk of chronic diseases and help you maintain a normal weight. Yet, one in three people worldwide gets little or no exercise at all.

The average weight gain per year after 30 has tended to increase as junk food became widely available. More than one-third of Americans consumed fast food on a given day between 2013 and 2016, as reported by the National Center for Health Statistics. In fact, older people carry almost 30 percent more fat, especially in the abdominal area, compared to when they were younger — and their eating and exercise habits have a lot to do with it.

While it's normal to gain some weight as you get older, that's not an excuse to overeat and stop being active. A review published in the ​International Journal of Cancer​ in April 2014 assessed the ​impact of weight gain and obesity on cancer risk​. As researchers point out, the risk of breast, endometrial and colorectal cancers goes up for every 5 percent increase in body weight from age 25 to baseline.

Another study, which appeared in the journal ​Circulation​ in December 2012, has linked age-related weight gain to hypertension. Young male adults of normal weight who had overweight or obesity by age 45 were ​twice more likely to develop high blood pressure​ than those who maintained their weight.

According to the American Council on Exercise, daily energy expenditure decreases by approximately ​150 calories per decade​ after age 20. This means that if you're 40 years old, you burn about 300 fewer calories per day compared to when you were in your early 20s.

However, there are ways to keep your metabolism up and maximize your energy expenditure. A balanced lifestyle that emphasizes regular exercise and healthy eating is essential.

​Read more:​ The Truth Behind 20 Diet and Exercise Myths

Metabolic slowdown is largely due to the hormonal changes and muscle loss associated with aging. For example, the North American Menopause Society reports that ​most women​ ​gain around 1.5 pounds per year​, especially in the midsection, because of the changes in hormone levels that occur during menopause. ​Aging itself​ plays a major role in this process. Additionally, the loss of estrogen promotes fat storage in the abdominal area.

Considering these facts, it's easy to understand why exercise and good nutrition are crucial. Simple lifestyle changes, such as filling up on protein, combining strength training and cardio and getting more sleep, can make all the difference. These habits support metabolic health, increase your energy expenditure and make it easier to maintain a healthy weight.

If you're short on time, split your training sessions into short bouts of exercise. According to a research paper published in the ​Journal of the American Heart Association​ in March 2018, squeezing in ​10-minute "mini workouts"​ throughout the day may lower the risk of death from all causes by 60 to 80 percent.

Keep your workouts short and intense. ​High-intensity interval training (HIIT)​, for example, burns fat and preserves lean mass while increasing post-exercise oxygen consumption. These facts combined lead to a faster metabolism.

​Read more:​ The "Choose Your Own Adventure" HIIT Workout

​A typical HIIT workout​ lasts 10 to 20 minutes, so you have no excuse to skimp on exercise. If you're just getting started, though, increase workout intensity gradually. This will reduce injury risk and allow your body to recover.