More than half of the world’s population still lacks sufficient protein, according to a study published in the New England Journal of Medicine.

“Our findings underscore the need to increase protein intake,” lead author Robert J. Siegel, a professor of nutrition at Yale University, said in a statement.

“The study underscores the importance of providing people with sufficient protein throughout their lives.”

Siegel and his colleagues looked at the dietary habits of 2,072 adults over the age of 60 who participated in the Harvard Health Study, a long-term study that tracked participants over several decades.

In addition to the usual foods, the researchers also measured a number of lifestyle factors.

Siegel said the study showed people with a low body mass index — the body mass in kilograms divided by the square of height — tended to eat less protein.

The participants with a high body mass were more likely to eat a high-protein diet.

But the researchers found the higher protein intake did not have a negative effect on their cardiovascular health or blood pressure.

Instead, the study found a negative relationship between the amount of protein consumed and their risk of developing a chronic disease such as cardiovascular disease, type 2 diabetes, cancer, or some other chronic condition.

While the overall body weight of the participants in the study was relatively low, the overall percentage of lean body mass was higher than in the general population, the authors said.

“We see that people who have a high protein intake are more likely than others to have higher cardiovascular risk, lower blood pressure, and lower risk of disease,” Siegel said.

However, the participants also had a lower waist circumference, lower waist-to-hip ratio, and less muscle mass than the general public, which may have been related to their diet, Siegel told Reuters Health.

Sugar-sweetened beverages also had negative effects on body weight, the team reported.

But eating a low-fat, high-sugar diet may have a similar effect, Sinkesaid.

People with a higher protein and low-carbohydrate diet may be less likely to develop these metabolic syndrome conditions.

Sinkesays there may be a link between protein intake and insulin resistance.

“A low protein intake could be an indirect cause of insulin resistance and type 2 diabetics,” he said.

In addition, people who had lower body mass and higher waist-hip ratios may be more likely, or have an increased risk of type 2 diabetic complications.

Sinking energy from protein, Sayer said, could be one reason why people with diabetes are eating less protein than the rest of the population.

“There are many other factors that may explain the low-protein pattern in the US,” Sayer told ReutersHealth.