(RxWiki News) Personal tastes determine what goes on many of our plates. But if longevity also is a concern, a new study suggests we’d fare better by dining on much less meat and many more vegetables.
Results from that study showed that meat eaters died sooner than those whose diets consisted of less meat.
"Limit meat in your diet."
Michael Orlich, MD, a PhD candidate in epidemiology at Loma Linda University School of Public Health in Loma Linda, CA, was the study’s lead author.
To explore the association between diet and mortality, the study tracked roughly 74,000 mainly white, but also black, residents of the United States who also were members of the Seventh Day Adventist Church. About 39,000 of them were vegetarian and 35,000 were not vegetarians.
On average, those men and women were in their mid to late 50s. None had previously been diagnosed with cancer, cardiovascular disease or strokes or had had heart surgery. They did not eat fewer than 500 calories daily or more than 4,500 calories per day.
The researchers described that group of 74,000 as representing about 425,000 “person years.” They then calculated mortality rates per 1,000 person years during the studied years, 2002 through 2007.
Among non-vegetarians, there were about 202,000 person years. There were 1,147 deaths, bringing the mortality rate for that group to 6.61, after researchers made statistical adjustments based on age, gender and race.
Among the study’s 4,031 semi-vegetarians, who researchers defined as eating fish or other meat no more than once weekly, there were 160 deaths and about 24,000 person years. That resulted in a mortality rate of 6.16.
Among the 21,177 lacto-ovo vegetarians — those eating eggs and dairy products but no more than one serving of fish or other meat per month — there were 815 deaths and almost 125,000 person years. Their morality rate was 5.61.
Among the 5,548 vegans — those defined as eating eggs, dairy products and fish and all other meats less than once monthly — there were 197 deaths and almost 33,000 person years. The group's mortality rate was 5.4.
Among the 7,194 fish-eating vegetarians — those defined as eating no more than one serving of meat a month — there were 251 deaths and roughly 42,000 person years, for a mortality rate of 5.33.
Lower rates of cancer, heart disease, kidney disease and disease from dysfunction in the endocrine glands, which control the body’s various hormones, have been associated with vegetarian diets, the researchers concluded.
Deborah Gordon, MD, is an Ashland, OR physician whose practice integrates Western medicine with homeopathy and focuses on nutrition and disease prevention.
Dr. Gordon, who reviewed Dr. Orlich's study, said it rightly notes reduced mortality from heart disease and other ailments among the various vegetarians. A good next step in dietary research would be studies that observe a more diverse population, not just one group such as these particular church members.
Additional studies should also be "interventional," she added, investigating what happens when certain healthy dietary changes are made. For example, what are the possible differences in how the body reacts to, say, grass-fed meat versus meat from cattle and poultry that are fed antibiotics and growth hormones?
Dr. Gordon also noted Seventh Day Adventists' embrace of whole grains, especially wheat, at mealtime.
"Remembering that our modern wheat is high in gluten and many people have gluten sensitivity, anyone who eats a lot of wheat would be wise to select their other foods wisely, both [in terms of] the nature and quantity of other foods," Dr. Gordon said. "I will continue to advise my patients to be most judicious about the quantity of their grains, [which should be] small, the manner of their preparation ... and the importance of quality in meat consumption ... Meat should be grass-finished and gently cooked."
For their part, the researchers noted, “Vegetarian diets have been associated with more favorable levels of cardiovascular risk factors, and nutrient profiles of the vegetarian dietary patterns suggest possible reasons for reduced cardiovascular risk, such as lower saturated fat and higher fiber consumption."
They continued, “Vegetarian diets are associated with lower all-cause mortality and with some reductions in cause-specific mortality ... These favorable associations should be considered carefully by those offering dietary guidance."
The National Cancer Institute funded the study. The Seventh Day Adventist Church has previously paid Dr. Orlich to deliver speeches about diet and healthy living.
This study was published June 3 in the Journal of the American Medical Association.