Plant-Based Diets Like the Portfolio Diet May Reduce the Risk of Cardiovascular Disease

Recently, two US studies involving large numbers of people over several years have published promising results on the benefits of a plant-based diet in reducing cardiovascular risk.

Heart Disease Prevention

With more than 890,882 deaths in the US in 2020, cardiovascular disease was the leading cause of death in the US after cancer and COVID-19. Additionally, hospital admissions for heart attacks are increasing in people under 65, especially women.

A healthy diet to prevent cardiovascular disease

Although many factors contribute to the risk of cardiovascular disease, nutrition, which is directly related to metabolism, is a well-developed area of prevention. Limiting fat and sugar and favouring fruit, vegetables, white meat and fish helps to prevent bad cholesterol, high blood pressure and diabetes which are determinants of cardiovascular risk.

The benefits of several diets have been recognized in relation to the prevalence of these pathologies. All are based on a high intake of whole grains, nuts, fruits, vegetables and legumes and a low intake of red meat, saturated fats and full-fat dairy products.

An example is the portfolio diet, which was developed by Dr David J.A. Jenkins, a British physician, has been shown to be effective in reducing bad cholesterol. This diet, based on plant fibre (fruit, vegetables, whole grains) and legumes (lentils, chickpeas), was supplemented with fish and white meat.

A cohort consisting of more than 123,000 postmenopausal American women (aged 50 to 79 years) was followed for several years (1993-2017) as part of the Women’s Health Initiative. The researchers wanted to see if participants who followed the cholesterol-lowering portfolio diet had fewer cardiovascular problems in the long term. The results were encouraging: women who followed the portfolio diet were 11% less likely to develop cardiovascular disease, 14% less likely to develop coronary heart disease, and 17% less likely to develop heart failure.

This study, whose strengths are its sample size and length of follow-up, demonstrates the long-term benefit of the portfolio diet in preventing cardiovascular disease. More direct evidence of causality is expected in ongoing randomised trials.

A study of 4 946 young adults over 32 years

In the Cardia (Coronary Artery Risk Development in Young Adults) study, conducted by four US universities since 1983, researchers followed a cohort of 4 946 young adults (aged 18 to 30 years in year 0) without cardiovascular disease for 32 years. Their diets during these years were assessed according to the A Priori Diet Quality Score (APDQS), which categorises foods into groups that are favourable or unfavourable for cardiovascular health. This diet is based on a predominantly plant-based diet that does not exclude animal products (poultry and unfried fish). The results of the study have just been published in the Journal of the American Heart Association. They showed a 52% reduction in cardiovascular risk in participants whose diets had a high ADPQS score.

This finding, which supports current recommendations, confirms that over the long term and from early adulthood, eating a plant-based diet is associated with a lower risk of cardiovascular disease in middle age. In addition, it shows that the complete exclusion of animal foods from the diet is not necessary.

According to the authors, this type of diet is less strict than a purely vegetarian diet and therefore offers more flexible options that may allow the general population to achieve and maintain a healthy daily diet in the long term.