Not all vegetarian diets are made equal

Eating a vegetarian diet is often seen as being the best choice for reducing the risk of heart disease. People often assume that it means eating strictly fruits and vegetables, but there is a vast array of choices available.

For someone to be considered vegetarian, they must not eat any animal derived products. With this logic, certain refined grains and sugar-sweetened beverages would be permitted — foods associated with a higher risk of cardio-metabolic disease.

This makes studying vegetarian diets and their impact on cardiovascular health difficult, as not all vegetarian/plant-based diets are made equal.

Looking at more than one type of plant-based diet

A new study crafted to help overcome these limitations created three versions of a plant-based diet. They included an overall plant-based diet emphasizing the consumption of all plant food and reduced animal food intake; a healthy plant-based diet emphasizing the intake of healthy plant foods such as whole grains, fruits, and vegetables; and lastly, an unhealthy plant-based diet emphasizing consumption of less healthy plant foods such as refined grains.

Over 200,000 men and women took part in the study. They responded to a follow-up questionnaire every second year for over 20 years. Aspects of lifestyle, health behaviors, and medical history were assessed. The participants diagnosed with coronary heart disease, stroke, cancer, or coronary artery surgery prior to the start of the study were excluded.

During the study, a total of 8,631 participants developed coronary heart disease.

Type of plant-based diet matters

The researchers found that overall, a plant-based diet was associated with a lower risk of heart disease. Those consuming a healthier plant-based diet rich in whole grains, fruits, and vegetables were found have an even lower risk of heart disease.

Diets with sweetened beverages, refined grains, potatoes, and sweets were seen to increase the risk of heart disease.

“When we examined the associations of the three food categories with heart disease risk, we found that healthy plant foods were associated with lower risk, whereas less healthy plant foods and animal foods were associated with higher risk. It’s apparent that there is a wide variation in the nutritional quality of plant foods, making it crucial to take into consideration the quality of foods in a plant-based diet,” said Ambika Satija, the study’s lead author.

The researchers hope that their study will inform people know that not all plant based diets reduce the risk of heart disease, with the wrong choices having an opposite effect. They go on to say that making smaller dietary tweaks over time rather than major changes can make a significant difference to your heart health and be more sustainable.

Related: Eating more plant-based foods decreases obesity risk