Health

This is the exact age when weight gain becomes fatal

The more overweight you are, the more likely you are to die.

Weight gain in early and middle adulthood will increase health risks later in life, according to a study released Tuesday by researchers at the Harvard T.H. Chan School of Public Health. People who gained a moderate amount of weight (5 to 22 pounds) before the age of 55 increased their risk of premature death, chronic diseases and decreased the likelihood of achieving healthy aging, the study found. And the higher the weight gain, the greater risk of chronic diseases.

“Our study is the first of its kind to systematically examine the association of weight gain from early to middle adulthood with major health risks later in life,” senior author Frank Hu, professor of nutrition and epidemiology and chair of the Department of Nutrition, said in a statement. The study analyzed data from nearly 93,000 participants.

Women gained an average of 22 pounds over this time, while men gained 19 pounds. “The findings indicate that even a modest amount of weight gain may have important health consequences.” Worse, early and middle adulthood is the time of life most people actually gain weight, as their metabolism slows, recurring knee and back injuries become more common, studies show; many people are also less active in their 30s and 40s when they work longer hours and have more responsibilities than, say, their carefree early 20s.

Being overweight or obese is associated with a higher risk of dying prematurely than being a healthier weight — and the risk increases with additional pounds, according to a separate international study released last year also by researchers at the Harvard T.H. Chan School of Public Health and the University of Cambridge in the U.K. Researchers joined forces in 2013 to establish the Global BMI (Body Mass Index) Mortality Collaboration, which included more than 500 investigators from over 300 global institutions.

Looking at specific causes of death, the study found that, for each five-unit increase in BMI (from, say, 30 to 35) — body mass index is measured by a formula that divides your body weight your height — the corresponding increases in risk were 49 percent for cardiovascular mortality, 38 percent for respiratory disease mortality and 19 percent for cancer mortality. That means these people are 49 percent, 38 percent and 19 percent more likely to die earlier than a person who has a healthy body weight.

BMI calculates weight, muscle, fat and bone in relation to height and gender. A BMI of 25 to 29.9 is considered overweight and those with a BMI of 30 or more are considered obese; morbidly obese people have a BMI of 44.9 or more. Adult obesity exceeds 30 percent of the population in 20 U.S. states and surpassed 35 percent in three states — Arkansas (35.9 percent), West Virginia (35.7 percent) and Mississippi (35.5 percent). Also, 22 states have rates above 30 percent, 45 states are above 25 percent, and every state is above 20 percent.

What’s more, the hazards of excess body weight were greater in younger than in older people and in men than in women, the researchers found. They crunched data from more than 10.6 million participants in 32 countries from 239 studies, conducted between 1970 and 2015. A combined 1.6 million deaths were recorded, in which participants were followed for an average of 14 years. Current or former smokers or those who had chronic diseases were excluded, as were those who died in the first five years.

There have been conflicting studies about obesity and mortality. In fact, a higher BMI may be associated with a lower mortality and a better outcome in several chronic diseases and health circumstances, according to a 2013 study published in Diabetes Care, the official journal of the American Diabetes Association. (The study also noted that BMI is “crude and flawed” and doesn’t take into account fat mass, nutrition, cardiorespiratory fitness, body fat distribution, or other factors affecting mortality.)

But this “obesity paradox” is flawed, the 2016 study argues. A low body weight could be the result of underlying illness rather than the cause. What’s more, smokers tend to weigh less than nonsmokers but have much higher mortality rates.

Still, as the mortality collaboration shows, there are significant health risks associated with being overweight. “Physicians need to counsel patients about the dangers of excess body weight which include a higher risk of Type 2 diabetes, cardiovascular disease, cancer and premature death,” says Shilpa Bhupathiraju, research scientist at the department of nutrition at the Harvard Chan School of Public Health.