Plant-based diets have been linked to a range of positive health impacts over the years, including improving gut health and reducing biological age.
A new review suggests yet another potential boon for this diet: urological health, i.e. health of the urinary system, including the kidneys, bladder, uterus and urethra.
Urological health, according to the study, is closely linked with general health. Obesity, for example, puts one at a higher risk of developing a range of urological cancers, such as prostate cancer, kidney cancer, and bladder cancer, as well as benign urological conditions like urinary tract infections and kidney stones. Diabetes is also linked to urological conditions, such as erectile dysfunction and some cancers.
Erectile dysfunction
The review links a plant-based diet with a lower risk of erectile dysfunction.
While not all studies looked at by the review found a clear link between plant-based diets and lower chance of erectile dysfunction, many did. One study found a clear higher consumption of plant-based foods among those who did not experience erectile dysfunction than those who did. Another study found that the higher the consumption of healthy plant-based foods was, the less risk of erectile dysfunction. It has also been found to have a favourable affect on those already experiencing erectile dysfunction.
“Erectile dysfunction is closely linked to cardiovascular disease so any dietary patterns that affect the health of blood vessels (for example, leading to atherosclerosis and inflammation in the blood vessels) will affect the quality of erections,” Loeb told us. Erectile dysfunction is also considered an early warning sign of cardiovascular disease.
Lowering cancer risk
According to the review, those following vegetarian and vegan diets have a lower risk of prostate cancer progression.
One study on those recovering from prostate cancer showed that those who were assigned to eat a plant-based diet showed a significant increase in doubling time for prostate-specific antigens (PSAs), which are found in higher concentrations in men with prostate cancer.
Across 17 publications pertaining to 11 observational studies, all demonstrated a reduced risk or no observable change of risk of prostate cancer among those who consumed a vegetarian or vegan diet, compared with those who consumed a meat-based diet. No study presented an increased risk of prostate cancer among those consuming a plant-based diet.
The review also found that omnivorous diets containing proportionally more plant-based foods are less likely to be associated with prostate cancer than those with proportionally greater animal-based food consumption.
The review also suggests that those consuming a meat-heavy diet may be more likely to develop kidney and bladder cancer than those consuming a plant-based diet, although the data in this case is more limited.
A pooled analysis of the Epic-Oxford and Oxford vegetarian studies showed a 53% reduced risk of bladder cancer among vegetarians after adjusting for confounders, with a follow-up analysis suggesting a 38% lower risk of bladder cancer for vegetarians than those who ate meat (although weight loss could be a mediating factor).
In a meta-analysis of 23 studies, an increased risk of renal cell cancer (a type of kidney cancer) was found to be associated with red meat, and processed meat was also associated with a higher risk. One large study, the Adventist Health Study, suggested those following a vegetarian diet were less likely to die from renal failure than non-vegetarians.
“There are multiple possible reasons for [the lower risk of cancer among those following plant-based diets], including carcinogenic compounds that are formed during high-temperature cooking (for example, heterocyclic amines), and by increasing levels of insulin-like growth factor 1 which promotes cell proliferation. Conversely, plant foods contain key elements like antioxidants and fibre which are beneficial for reducing the risk of cancer. Thus, consuming fewer meat products and more plant-products are both important factors when it comes to cancer risk,” Stacy Loeb, one of the authors of the review, told FoodNavigator.
Urinary tract infections
One of the most common bacterial infections worldwide, urinary tract infections are also inversely associated with plant-based diets, according to the review. One study, which followed 9724 people for ten years, found that those who ate a vegetarian diet had an 18% lower risk of urinary tract infection.
Emerging data suggest that this link could be due to the influence of diet on the gut microbiota. E. coli isolates from products such as retail chicken have been shown to be either genetically indistinguishable from, or closely related to, isolates from human UTIs. This could suggest that retail meat and poultry could act as a reservoir for E. coli, in turn causing human extraintestinal infections.
Kidney stones
Studies have also shown that a vegetarian diet reduces the risk of kidney stones. For example, results from the European Prospective Investigation into Cancer and Nutrition showed that those consuming a vegetarian diet have 31% less risk of developing kidney stones than those with a meat intake of more than 100kg a day. Increased intake of fresh fruit lowered risk.
“Kidney stones are closely related to diet. Eating animal protein lowers the urinary pH and increases urinary calcium and uric acid, which predispose to the formation of stones. Conversely, diets enriched in plants can increase urine pH and contain stone inhibitors such as phytate, citrate, potassium, and magnesium, which decrease the risk of stones,” Loeb told us.
However, some unhealthy plant-based foods, such as sugar-sweetened beverages and salted vegetables, are actually linked to an increased risk of kidney stones.
Sourced From: Nature Reviews Urology
'Plant-based diets and urological health'
Published on: 7 October 2024
Doi: https://doi.org/10.1038/s41585-024-00939-y
Authors: S. Loeb, J. F. Borin, G. Venigalla, M. Narasimman, N.Gupta, A. P. Cole, K. Amin