Meat eaters up to 16% more likely to suffer a stroke, finds AHA study
09 Nov 2021 --- Eating higher quantities of red meat, processed red meat and non-dairy animal fat raise the risk of stroke, while consuming more vegetable fat or polyunsaturated fat lowers it, according to new preliminary research by the American Heart Association (AHA).
The study, which claims to be the first to comprehensively analyze the impact on stroke risk from fat derived from vegetable, dairy and non-dairy animal sources, indicates that the type of fat consumed is more important than the total amount of dietary fat in preventing strokes.
Speaking to NutritionInsight, the study’s lead author Fengei Wei, a postdoctoral fellow in the department of nutrition at Harvard’s T.H. Chan School of Public Health in Boston, US, says the findings “were not very surprising.”
“This has been consistent with the dietary recommendations by AHA and other health organizations that we should be consuming more healthy plant foods and less red and processed meat.”
The findings, so far unpublished, are being presented at the AHA’s Scientific Sessions 2021.
Meat eaters should be mindful of eating leaner cuts of meat to avoid animal fats, indicate the AHA.Cutting meat to avoid stroke
The investigators analyzed 27 years of follow-up data from 117,136 participants in the Nurses’ Health Study (1984-2016) and Health Professionals Follow-up Study (1986-2016) – two of the largest US studies to examine the risk factors for various chronic diseases.
At the beginning and every four years during the study, participants completed food frequency questionnaires to calculate the amount, source and types of fat in their diets over the previous year.
Researchers then calculated the cumulative average of the dietary data over time to reflect long-term dietary intake.
During the study, 6,189 participants had strokes, including 2,967 ischemic strokes (caused by a clot cutting off blood flow to part of the brain) and 814 hemorrhagic strokes (caused by bleeding of vessels in the brain).
Participants in the highest quintile of non-dairy animal fat intake were 16% more likely to experience a stroke than those who ate the least. Dairy fat in products, such as cheese, butter, milk, ice cream and cream, was not associated with a higher risk of stroke.
Participants who ate the most vegetable fat and the most polyunsaturated fat were 12% less likely to experience a stroke compared to those who ate the least. Those consuming one more serving of total red meat every day had an 8% higher risk of stroke, and those consuming one more serving of processed red meat had a 12% higher risk of stroke.
Industry and government guidance 
The AHA is recommending consumers switch to more plant-based diets to avoid severe illness like strokes.Wei says the findings should drive help for consumers to eat leaner cuts of meat where possible.
“One of our recommendations for the general public is to minimize fatty parts of unprocessed meat if consumed to lower their stroke risk. Policymakers and industry could create an environment with more lean cuts of meat for consumers to buy.”
“We recommend for the general public to reduce consumption of red and processed meat, minimize fatty parts of unprocessed meat if consumed, and replace lard or tallow (beef fat) with non-tropical vegetable oils such as olive oil, corn or soybean oils in cooking to lower their stroke risk,” she says.
The AHA further notes that replacing processed meat with other protein sources, particularly plant sources, is associated with lower death rates.
Future research
Wei says the biological mechanisms underlying the various associations between vegetable fat and non-dairy animal fat with stroke risk are unclear and warrant further investigation.
“Currently, we don’t have more detailed information on the subtypes of dietary fat (for example, different subtypes of saturated fat from vegetable, dairy, or non-dairy animal foods). This would be useful in evaluating this association because types of fat and fat from different sources are not mutually exclusive,” she says.
“We did not observe associations between saturated fat and stroke risk. But the associations might differ for saturated fat from vegetable, dairy, or non-dairy animal foods. For future steps, finer categories will help us better understand how types and sources of fat are associated with the disease risk.”
By Louis Gore-Lagton
