vegetarian vs. non-vegetarian diets within the battle against cardiometabolic diseases

In a recent study published within the Nutrition, Metabolism and Cardiovascular Diseases Journal, researchers conducted a comprehensive review to check the impacts of vegetarian and non-vegetarian diets on the outcomes of major cardiometabolic and other non-communicable diseases.

Study: A comprehensive review of healthy effects of vegetarian diets. Image Credit: Elena.Katkova/Shutterstock.com

Background

The opinions concerning the association between meat consumption and health have been divided, with diets low in or devoid of animal food sources being considered low in dietary content, leading to essential nutrient deficiencies.

Emerging research supports contrasting opinions that plant-based diets meet the regular dietary requirements and supply various health advantages, corresponding to lowering the risks of multiple diseases.

Nonetheless, the term ‘vegetarian’ is used loosely to encompass various dietary patterns corresponding to vegan, ovo-vegetarian, lacto-vegetarian,  lacto-ovo-vegetarian, and semi-vegetarian.

Vegetarian diets also range from the Western patterns of vegetarianism mentioned above to dietary patterns based on ethnicities, corresponding to Buddhist or Asian diets, where the supply of animal food sources or socio-economical or cultural aspects influences the eating regimen.

This wide selection of variations in vegetarian diets has resulted in contrasting results amongst studies that examine the connection between vegetarian diets and health advantages.

Individuals in developing countries generally follow a more balanced and well-developed vegetarian eating regimen as compared to those in developing countries where access to food relies on socioeconomic aspects.

In regards to the study

In the current study, the researchers conducted a comprehensive review of research that examined various vegetarian diets and their effects on outcomes related to health, including the risks of varied non-communicable diseases.

Studies examining various forms of vegetarian diets, from Western vegetarian dietary patterns to vegetarian diets influenced by religious beliefs, were reviewed.

The non-communicable diseases examined within the review broadly included cardiovascular, cerebrovascular, cardiometabolic diseases, obesity, hypertension, dyslipidemia, metabolic syndrome, and sort 2 diabetes.

Observational studies and randomized controlled trials that compared the consequences of vegetarian diets with those of non-vegetarian or omnivore diets were included.

Moreover, for every category of non-communicable diseases, the researchers conducted an intensive literature search using a wide selection of keywords related to the disease.

The review included cohort studies, randomized controlled trials, longitudinal studies, and prospective cohort studies that reported on the comparative effects of vegetarian and non-vegetarian diets within the context of disease risk.

Results

The outcomes reported that while it seems that following vegetarian diets may assist in reducing the danger of cardiometabolic diseases, the non-uniformity of the findings as a consequence of the cultural and ethnic differences within the approach to vegetarianism, in addition to as a consequence of differences in methodology across the studies makes it difficult to form definitive inferences.

Several cohort studies within the review reported that following a vegetarian eating regimen in comparison with a non-vegetarian eating regimen was advantageous in lowering the danger of incidence and mortality related to obesity, chubby, and ischemic heart disease.

Vegetarian diets were also linked to a lower risk of hypertension and positively affected plasma parameters and sort 2 diabetes risk.

Moreover, while cohort studies reported mixed results on the consequences of vegetarian diets on metabolic syndromes, randomized controlled trials reported that vegetarian diets, especially those involving low-fat foods, improved glycemic control and resulted in higher weight reduction in comparison with non-vegetarian diets.

One randomized controlled study also reported improvements in coronary atherosclerosis related to vegetarian diets. In contrast, most randomized controlled studies reported a lowering of blood pressure and low-density lipoprotein-cholesterol levels, albeit with an accompanied lowering of high-density lipoprotein levels.

The researchers also discussed the possible mechanisms that designate the association between vegetarian diets and the reduced risk of many non-communicable diseases.

They imagine that while the health advantages of vegetarian diets might sometimes be specific for certain diseases, often, the etiopathogenetic mechanisms of many diseases are shared, and the impact of vegetarian diets in lowering the risks of such diseases is thru more generalized mechanisms.

The low to no animal food content of vegetarian diets leads to a lower intake of saturated fats and reduces the detrimental effects of excess animal proteins and heme-irons.

Moreover, the high fiber, polyunsaturated fatty acid, complex carbohydrate, and micronutrient content of plant-based diets also improve conditions corresponding to type 2 diabetes, hypercholesteremia, and chubby.

Whole plant food consumption has also been encouraged as a consequence of its advantages in decreasing oxidative stress and inflammation and improving insulin sensitivity and endothelial function.

Conclusions

Overall, the review covered a comprehensive set of studies that compared the impacts of vegetarian and non-vegetarian diets on overall human health and in lowering the danger of many non-communicable diseases.

Although many studies have reported that vegetarian diets have various useful effects on human health and are believed to lower the incidence and mortality risks of major non-communicable diseases, the methodologies and classifications of vegetarian diets proceed to be too non-uniform to form definitive inferences on the topic.