As part of the new study, researchers looked at 30 randomized trials with 2,372 participants, published between 1982 and 2022. They examined the effect of vegetarian or vegan diets compared to omnivorous diets, which include animal and plants, on the following:

• Total cholesterol 
• Low-density lipoprotein, also called LDL or “bad” cholesterol
• Triglycerides; a type of fat, or “lipid,” found in the blood
• Apolipoprotein B, also known as apoB, a type of protein that helps carry fat and cholesterol in the blood

This is the first meta-analysis on the topic to publish since 2017 and the first to look at the impact of continent, age, body mass index, and health status, as well as the effect diet has on concentrations of apoB, which is a good indicator of the total amount of bad fats and cholesterol in the body.

Benefits of a plant-based diet

“We found that vegetarian and vegan diets were associated with a 14% reduction in all artery-clogging lipoproteins as indicated by apolipoprotein B. This corresponds to a third of the effect of taking cholesterol-lowering medications such as statins, and would result in a 7% reduction in the risk of cardiovascular disease in someone who maintained a plant-based diet for five years,” Dr. Ruth Frikke-Schmidt, chief physician at the Rigshospitalet in Copenhagen, who conducted the study along with colleagues, said in a press release about their work. 

Frikke-Schmidt also said that statin treatments, a group of medications that can help lower LDL cholesterol, are “superior” to plant-based diets when it comes to reducing fats and cholesterol levels; however, “one regimen does not exclude the other, and combining statins with plant-based diets is likely to have a synergistic effect, resulting in an even larger beneficial effect.”

Compared to omnivores, those eating a plant-based diet experienced an average decrease in total cholesterol levels of 7% from levels noted at the beginning of the studies; a 10% reduction in LDL cholesterol levels; and a 14% reduction in apoB levels.

In addition to lowering the risk of heart disease, other benefits of a plant-based diet include a reduced risk of:

• Diabetes
• Dementia
• High blood pressure
• Obesity
• Certain types of cancers, such as colon, breast, and prostate cancer
• Depression
• Frailty in older adults

“If people start eating vegetarian or vegan diets from an early age, the potential for reducing the risk of cardiovascular disease caused by blocked arteries is substantial,” Frikke-Schmidt continued. “Importantly, we found similar results across continents, ages, different ranges of body mass index, and among people in different states of health.”

A global effect

In addition to the health benefits for humans, plant-based diets have a positive impact on the environment, according to research.

“Recent systematic reviews have shown that if the populations of high-income countries shift to plant-based diets, this can reduce net emissions of greenhouse gases by between 35% to 49%. Our study provides robust evidence that plant-based diets are good for our health for people of different sizes, ages, and health conditions,” said Frikke-Schmidt. 

Vegetarian and vegan diets may even help offset the rising costs of age-related diseases facing a globally aging population, experts say.

“Plant-based diets are key instruments for changing food production to more environmentally sustainable forms, while at the same time reducing the burden of cardiovascular disease,” said Frikke-Schmidt. “We should be eating a varied, plant-rich diet, not too much, and quenching our thirst with water.”