Scientific Update
By Reed Mangels, PhD, RD
Urinary Tract Infections in Vegetarians
If you've ever had a burning sensation when urinating or cloudy, strong-smelling
urine, you may have had a urinary tract infection (UTI). A UTI can affect your
kidneys, ureters, bladder, and urethra. Each year, more than 3 million cases are
reported in the U.S. Women are more likely to get UTIs than men are. Researchers in
Taiwan studied more than 9,700 Buddhists, 30% of whom were vegetarian, for nine
years. Vegetarians, especially vegetarian women, were significantly less likely to
develop UTIs than were nonvegetarians. The researchers provided an interesting
hypothesis to explain their results, namely that bacteria from animal sources play
an important role in UTIs. They note that the strains of E. coli bacteria that are a
common cause of UTIs are highly similar to E. coli strains found in poultry and
pork. Urine samples from people with UTIs contain E. coli bacteria that are
virtually identical to the disease-causing E. coli bacteria from chickens and pigs
and different from the strains of E. coli normally found in the human intestinal
tract. Vegetarians would be less likely to be exposed to these disease-causing
bacteria and this could explain their lower rates of UTIs.
Chen YC, Chang CC, Chiu THT, Lin MN, Lin CL. The risk of urinary tract infection in vegetarians and non-vegetarians: a prospective study. Sci Rep. 2020;10(1):906.
Vegetarian Pregnancy
The nine months of pregnancy and the two years after birth are important times for
the baby's brain development. Some of the nutrients known to be important for the
developing nervous system are iron, vitamin B12, iodine, and the omega-3 fatty acid
DHA. Some studies show that intakes of one or more of these nutrients may be lower
in vegetarians.
A British study examined 78 vegetarians and 2,144 nonvegetarians in the early part of their pregnancy and 91 vegetarians and 2,552 nonvegetarians who were near the end of their pregnancy. Women were categorized as vegetarian if they reported not eating any meat or fish in the three months before the study started. The study's purpose was to see if eating a vegetarian diet during pregnancy affected the baby's mental development. The researchers examined IQ and other measures of development in children whose mothers were or were not vegetarian during pregnancy. They found that there was no significant difference in IQ or other measures between the two groups.
For more information about vegetarian, including vegan, pregnancy, visit The Vegetarian Resource Group website at www.vrg.org/nutrition/veganpregnancy.php.
Crozier SR, Godfrey KM, Calder PC, et al. Vegetarian diet during pregnancy is not associated with poorer cognitive performance in children at age 6-7 years. Nutrients. 2019 Dec 11;11(12).
Certain Food Choices Promote Health and the Environment
Common diseases, including heart disease, type 2 diabetes, stroke, and colorectal
cancer, account for nearly 40% of deaths globally. Not surprisingly, all these
conditions are affected by food choices. Planetary health is also affected by food
choices. Could there be a connection between what's good for human health and for
planetary health? If you nodded your head "yes," you're right. A group of
researchers investigated the human health and environmental impacts of 15 different
food groups including eggs, dairy products, chicken, fish, processed and unprocessed
red meat, legumes, nuts, fruits, whole grains, and vegetables. They examined the
connection between the selected food groups and risk of heart disease, type 2
diabetes, stroke, colorectal cancer, and death. They also looked at five
environmental outcomes — greenhouse gas emissions, land use, water use,
acidification, and eutrophication (an excess of nutrients in a body of water
frequently due to runoff and resulting in death of fish and other animals).
Not surprisingly, they found that eating more whole grains, fruits, vegetables, legumes, olive oil, nuts, and fish was associated with a lower risk of death or of developing one or more of the previously mentioned diseases. Eating more red or processed meat is associated with an increased risk of these diseases. In terms of the environment, minimally processed plant foods, including legumes, fruits, vegetables, nuts, and whole grains, have the lowest environmental impacts. Dairy products, eggs, fish, and chicken are intermediate in terms of environmental impact, and red and processed meat have the highest environmental impact. The researchers concluded that producing a single serving of red or processed meat has 10 to 100 times the impact that producing a serving of plant foods has on greenhouse gas emissions, land use, acidification, and eutrophication. While these results may not be surprising to readers, they certainly point to the many benefits of eating a vegan diet based on unprocessed foods.
Clark MA, Springmann M, Hill J, Tilman D. Multiple health and environmental impacts of foods. Proc Natl Acad Sci USA. 2019;116(46):23357-23362.
Vegetarians May Have Lower Healthcare Costs
Health care costs are a substantial part of most people's budgets. Whether it's
health insurance, medications, doctor visits, or hospital bills, many of us are
concerned about the rising cost of health care. Could the food choices we make
affect our health care costs? A study from Taiwan suggests that, on average,
vegetarians may have lower medical expenses.
This study compared vegetarians and nonvegetarians in a Buddhist community where there was little or no use of alcohol or tobacco. In other words, these study subjects were already at a lower risk for some chronic diseases. The study also compared this community's medical expenses to those of the general population.
More than 6,000 people participated in this study. About 30% were classified as vegetarian (no meat or fish; used dairy and eggs). Medical costs of subjects were determined over five years using data from the Ministry of Health of Taiwan. Compared to non-vegetarians, vegetarians spent 15% less on total healthcare and 13% less on outpatient healthcare. A vegetarian diet was associated with a 28% reduction in expenses related to hypertension and a 31% reduction in expenses related to high blood lipids like cholesterol.
Compared to the general population, vegetarians had a 25% lower healthcare expenditure. While it is possible that vegetarians were less likely to seek healthcare, it's also possible that they were more likely to seek preventive care, which would increase costs short-term but potentially result in lower long-term costs. Additional research is needed to determine why the lower healthcare costs were seen in vegetarians. Ideally, a similar study would be conducted in the United States.
Lin CL, Wang JH, Chang CC, Chiu THT, Lin MN. Vegetarian diets and medical expenditure in Taiwan — a matched cohort study. Nutrients. 2019;11(11).
New Study Does Not Find Increased Stroke Risk in Vegetarians
In the last issue of Vegetarian Journal, we reported on a U.K. study that found that
vegetarians (including vegans) had a higher risk of a kind of stroke called
hemorrhagic stroke and of stroke overall than did meat eaters. A recently published
study from Taiwan also examined stroke rates in vegetarians and found that
vegetarians (did not eat meat or fish) had lower rates of hemorrhagic stroke and of
stroke overall than did nonvegetarians. The authors of the Taiwan study note that
their vegetarian subjects avoid alcohol whereas the British subjects were more
likely to drink. Since some studies show a higher stroke risk with higher alcohol
consumption, the researchers theorize that the British subjects' alcohol use could
supersede protective effects of their vegetarian diet.
Chiu THT, Chang HR, Wang LY, Chang CC, Lin MN, Lin CL. Vegetarian diet and incidence of total, ischemic, and hemorrhagic stroke in 2 cohorts in Taiwan. Neurology. 2020 Feb 26. [Epub ahead of print].
