People on plant based diets who consume lots of refined grains and sugars may be significantly more likely to develop heart disease than vegetarians whose diets include the least amount of these types of foods, a study suggests.
Plant based diets are recommended for coronary heart disease (CHD) prevention. However, not all plant foods are necessarily beneficial for health.
A study published in the Journal of the American College of Cardiology included 73710 women in NHS (Nurses’ Health Study; 1984 to 2012), 92329 women in NHS2 (1991 to 2013), and 43259 men in a Health Professionals Follow-up Study (1986 to 2012), free of chronic diseases as a baseline.
Researchers created an overall plant based diet index (PDI) from repeated semi quantitative food frequency questionnaire data, by assigning positive scores to plant foods and reverse scores to animal foods.
Scientists also created a healthful plant based diet index (hPDI) where healthy plant foods (whole grains, fruits/vegetables, nuts/legumes, oils, tea/coffee) received positive scores, whereas less-healthy plant foods (juices/sweetened beverages, refined grains, potatoes/fries, sweets) and animal foods received reverse scores.
To create an unhealthful PDI (uPDI), positive scores were given to less healthy plant foods and reverse scores to animal and healthy plant foods.
The researchers found that for over 4833042 person years of follow up, 8631 incident CHD cases were documented. The study concluded that higher intake of a plant based diet index rich in healthier plant foods is associated with substantially lower CHD risk, whereas a plant based diet index emphasising less healthy plant foods is associated with higher CHD risk.
References:
- Ambika Satija et al., “Healthful and Unhealthful Plant-Based Diets and the Risk of Coronary Heart Disease in US Adults”, Journal of the American College of Cardiology, 70(4), 411-422 (2017).