Flexitarian diet linked to lower cardiovascular risk, study finds

By Dr. Liji Thomas, MDFeb 13 2024Reviewed by Benedette Cuffari, M.Sc.

A new study published in BMC Nutrition examines the cardiovascular risk associated with different dietary patterns.

Study: Plant-based diets and cardiovascular risk factors: a comparison of flexitarians, vegans and omnivores in a cross-sectional study. Image Credit: Antonina Vlasova / Shutterstock.com

How different diets impact cardiovascular health

Omnivorous diets are often rich in meat and meat products, with the average intake in Germany being above the recommended limit of 600 grams each week. High meat intake has been associated with an increased risk of obesity, high blood pressure, insulin resistance, abnormally high blood lipids, and arterial stiffening, all of which are risk factors for cardiovascular disease (CVD).

In contrast, less than 40% of people in Germany are physically active, most of whom spend less than 2.5 hours every week in physical activity. However, moderate activity could reduce the risk of atherosclerosis, a prime risk factor for CVD.

CVD is the leading cause of death around the world, as it accounts for over half of all deaths. Both modifiable and non-modifiable risk factors contribute to the development of CVD, the latter of which include a poor diet and unhealthy lifestyle.

Ecologists claim that a plant-based diet is ideal for the earth’s human population in terms of health, sustainability, animal welfare, and cost-effectiveness. However, rather than an all-or-nothing approach, there could be a happy medium with people mainly eating plant-based food coupled with occasional meat and processed meat intake. In contrast to vegetarians, this type of individual is referred to as a flexitarian.

While the typical omnivore diet has been associated with an increased CVD risk, a plant-based diet appears to reduce the risk of CVDs. However, little research to date has evaluated the impact of a flexitarian diet on CVD risk.

About the study

Study participants between 25 and 45 years old were divided into three groups. The first group comprised long-term flexitarians (FXs) who ingested 50 grams of meat or meat products each day, whereas the second group consisted of vegans who did not eat any foods of animal origin, and the third group included omnivores, whose diet included 170 grams of meat and meat products every day.

The researchers examined blood samples for various markers of CVD, blood pressure, arterial wall compliance, and whether the individual had metabolic syndrome (MetS), characterized by insulin resistance, high blood glucose levels, and an increased weight circumference. These measurements were compared with dietary patterns using multiple tools to characterize diet quality, food intake, and physical activity levels.

What did the study show?

Body mass index (BMI) values were similar for all three groups; however, FX women had lower body fat than omnivore women, with this difference not observed in men. Vegan women had the lowest body fat percentage of all study participants.

Vegetable intake increased from omnivores to vegans, with FXs and vegans consuming twice and three times as much vegetables as omnivores, respectively. Both vegans and FXs consumed twice as many fruits as omnivores.

FXs consumed significantly fewer plant-based milk or dairy alternatives, with neither favored among omnivores. Similar patterns were observed for nuts and legumes.

Meat intake was lowest among vegans and significantly less among FXs as compared to omnivores. Plant-based meat alternatives were primarily consumed among vegans, with some intake reported among FXs. Egg intake was double among omnivores as compared to FXs.

The best diet quality was observed among vegans, followed by FXs, which correlates with previous reports.

All CVD markers were at similar levels in all groups, whereas the lowest fasting glucose levels were observed in vegans. MetS marker scores were significantly better in vegans and FXs than omnivores; however, all groups were associated with low-risk score levels.

Meat and dairy intake were closely associated with total cholesterol levels; however, dairy intake was negatively correlated with fruit and vegetable intake, including legumes and meat substitutes. Soft drinks, sweets, and meat consumption were correlated with increasing low-density lipoprotein (LDL) cholesterol.

MetS scores were related to processed meat and meat consumption and sweets intake but negatively associated with fruit intake. Total inflammation was not correlated with any group.

What are the implications?

Dietary choices are crucial to reducing CVD risk, as confirmed by this pilot study on the flexitarian diet in relation to CVD risk factors. Although not an intervention study, the current study allowed for direct observation of several parameters in three distinctive groups, especially MetS scores and arterial stiffness.

A vegan diet appears to be associated with the best cardiovascular health; however, MetS and arterial stiffness were more favorable in flexitarians than in the other groups. Thus, flexitarian diets also confer significant benefits compared to omnivorous eating patterns.

Reducing meat and processed meat products intake, as in flexitarianism, may contribute to CVD risk factor advantages.”