In a recent study published in Frontiers in Nutrition, researchers examine the influences of vegetarian and non-vegetarian diets on the prevalence of varicose veins in males and females.
Study: The association between a vegetarian diet and varicose veins might be more prominent in men than in women. Image Credit: Antonina Vlasova / Shutterstock.com
Background
Varicose veins are a vascular disease characterized by the formation of dilated, prominent, visible, and tortuous subcutaneous veins in the legs. Varicose veins are a degenerative condition that worsens over time and places a considerable burden on individuals and the public health system. Studies from the United Kingdom reported that in over half the patients, the condition deteriorates over time, often leading to ulceration and pigmentation.
The risk factors for varicose veins include age, parity, obesity, long hours spent standing, and heavy lifting.
A large body of evidence indicates that a vegetarian diet reduces the risk of cardiovascular disease, coronary heart disease, and associated mortality. A plant-based diet has also been linked to a reduced risk of cerebrovascular disease, type 2 diabetes, metabolic syndromes, heart failure, improved lipid profiles, lower blood pressure, and weight management.
However, the impact of a vegetarian diet on the pathogenesis of varicose veins has not been investigated.
About the study
In the present study, researchers obtained data for 9,905 adult participants from the Taiwan Biobank. This database comprises population-level data on lifestyle choices, medical history, anthropometric measurements, biochemical markers, and personal information gathered through biochemical and physical examinations and detailed questionnaires.
The questionnaires obtained information on the incidence of varicose veins and other lifestyle factors such as vegetarian diet, alcohol consumption, smoking behavior, and exercise, as well as covariates such as age, educational levels, and occupation. Varicose veins were defined as the presence of distorted blood vessels on the limbs ranging from mild to very severe over the past month or more.
Vegetarianism was defined as a daily vegetarian lifestyle for the last six months or more. Lifestyle and behaviors such as alcohol consumption, cigarette smoking, and exercise were coded as present or absent. At the same time, body mass index (BMI) values were calculated to categorize the participants into normal weight, underweight, overweight, and obese categories. Jobs that required prolonged periods of standing included pharmacists, teachers, nurses, and soldiers.
Vegetarian diet increases risk of varicose veins in men
Irrespective of the diet, women were more susceptible to developing varicose veins than men. However, when the association was investigated in terms of the diet alone, men who follow a vegetarian diet were at a greater risk of developing varicose veins than men who had a more diverse and omnivorous diet. The sex-stratified analysis also revealed that the risk of developing varicose veins was significantly higher in non-vegetarian and vegetarian women, as well as vegetarian men.
The potential causes of the increased risk among women developing varicose veins could be due to sex hormones and pregnancy. This is supported by in vivo studies in mice demonstrating that the depletion of sex hormones resulted in reduced vein diameter and contractility of blood vessels. Other studies have discussed the association between an increased incidence of varicose veins among women and the presence of progesterone and estrogen receptors in the tunica layers.
While previous studies have reported the beneficial effects of a vegetarian diet on various aspects of human health, such as glycemic control, lipid reduction, blood pressure, and atherosclerosis risk, the findings of the present study were in striking contrast to these observations. In fact, vegetarian men were found to be 1.45 times more likely than omnivore men to develop varicose veins.
Although the mechanisms responsible for this negative association between the occurrence of varicose veins and vegetarianism have not been explored, the researchers of the current study speculate that this association could be based on the low levels of serum ferritin in vegetarian men. A vegetarian diet has been associated with iron deficiency, which could lead to atrophic gastritis and various downstream processes.
While some studies have reported that the vegetarian diet also results in lower levels of vitamin B12, there is a paucity of data on the roles of vitamins and minerals in the development of varicose veins.
Homocysteine, an amino acid with a sulfur group, plays a significant role in inflammation, vascular wall maintenance, and endothelial dysfunction. To date, the impact of a vegetarian diet on homocysteine levels has not been examined.
Conclusions
Women had a higher risk of developing varicose veins than men, irrespective of their diet. Men who followed a vegetarian lifestyle were at a significantly higher risk of developing varicose veins than men who were on an omnivorous diet.
Journal reference:
- Tsai, C., Nfor, O. N., Tantoh, D. M., Lu, et al. (2023). The association between a vegetarian diet and varicose veins might be more prominent in men than in women. Frontiers in Nutrition 10. doi:10.3389/fnut.2023.1046158
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