New data presented at Nutrition 2018 — the flagship meeting of the American Society for Nutrition, held in Boston, MA — bolster the evidence that a plant-based diet is linked to a wealth of health benefits.

The latest research backs up the health benefits of vegetarianism.

Plant-based diets are becoming more popular in the United States. A 2017 report found that 6 per cent of people in the U.S. now identify as vegan, compared with just 1 per cent in 2014.

Despite this steady growth, the U.S. still lags behind many other countries when it comes to swapping animal protein for plant protein. In Germany, for example, nearly half of consumers currently follow a low-meat diet.

The results of studies from the Netherlands, Brazil, and the U.S., presented at Nutrition 2018, all found benefits associated with vegetarian-type diets, but they also communicated the health importance of the quality of the food.

We present some top-line findings from these studies below. When reading these summaries, it is important to bear in mind that while the abstracts presented at Nutrition 2018 were evaluated and selected by a committee of experts, the papers have not undergone the same rigorous standard of peer review that is applied to scientific journals.

So, we should consider these findings as "preliminary results," until they are properly assessed.

Vegetarians and heart-related illness

The study from the Netherlands looked at almost 6,000 people; the team found that those who ate a high ratio of plant-derived protein to animal-derived protein were at lower risk of developing coronary heart disease later in life.

The Brazilian study looked at around 4,500 people and concluded that people who had a diet rich in plant-based protein were 60 percent less likely than people who had a diet rich in animal-based protein to develop a buildup of plaque in the arteries of the heart.

A diet rich in plant-based foods and low in meat — without strictly following a vegetarian diet — may offer protection against obesity

And, a study looking at South Asian people living in the U.S. found that vegetarianism was associated with fewer risk factors for diabetes and heart disease.

Compared with their nonvegetarian peers, South Asian vegetarians exhibited:

• smaller waist circumference
• lower amounts of abdominal fat
• lower cholesterol
• lower blood sugar
• lower body mass index (BMI)
• They were also less likely to gain weight and had a lower mortality rate.

Food quality is still important

In another study, researchers from Harvard T. H. Chan School of Public Health in Boston, MA, examined whether there was an association between eating healthful plant-based foods and reduced weight gain.

Examining data from "more than 125,000 adults over 4-year periods," the team found that people who ate a lot of high-quality plant-based foods, such as whole grains, nuts, vegetables, and fruits, were less likely to gain weight than people who ate a lot of less healthful plant-based foods, such as fries, refined grains, and candy.

A team at Friedman School of Nutrition Science and Policy at Tufts University in Medford, MA, found in its study of nearly 30,000 people in the U.S. that the quality of plant-based foods is "more important than the quality" of animal-derived foods when it comes to dietary health.

Their data map an association between making strong dietary choices for healthful, high-quality plant-based foods and a 30 percent lower mortality rate. People with chronic health conditions who consumed a diet rich in high-quality plant-based foods were found to benefit even more than those in the general population.

Consuming high-quality animal-based foods, however, was not associated with any significant benefits for mortality.