WURZBURG, Germany, Thursday December 10, 2015 – Red meat has received a lot of bad press recently – mostly for its perceived link to cancer. But a new study suggests an increased stroke risk, with the odds going up the more meat people eat.
German researchers analysed data on about 11,000 middle-aged people who had no other risk factors for strokes such as heart disease or diabetes, and followed half of them for 23 years.
The participants who consumed the most red meat had a 47 percent higher risk of ischemic stroke – caused by blockages in blood vessels supplying the brain – than those who typically ate the smallest amount of red meat.
Protein from poultry, seafood or vegetable sources like nuts and legumes was not associated with any added risk.
While some previous research has linked high-protein diets to strokes, the results have been mixed and the current study helps solidify the evidence suggesting that red meat in particular may pose a danger, said lead study author Dr Bernhard Haring of the Comprehensive Heart Failure Centre at the University of Wurzburg.
To assess the link between protein consumption and stroke risk, Haring and colleagues reviewed data from diet questionnaires completed by US residents aged 45 to 64 starting in 1987.
The researchers followed their progress through 2011 to see how many people had suffered a stroke.
The participants were divided into five groups based on how much protein and what type they consumed.
The bottom-fifth, for instance, averaged about 49 grams of protein a day, representing less than 13 percent of total calories. The top-fifth averaged 93 grams of protein a day, representing 23 percent of total calories.
Participants who ate less protein on average at the start of the study were more likely to be black, smokers, and less likely to have regular exercise routines. The people who ate less protein were also less likely to be obese or take cholesterol-lowering medications.
There were no major differences in age, gender, or total calories consumed among participants who ate different amounts of protein.
There were 699 strokes among 11,601 participants during a median follow-up of 22.7 years.
The highest intake of processed meats like bacon, sausage and jerky was linked to a 24 percent higher risk of strokes, while the highest consumption of red meat was tied to a 41 percent increased risk, compared to people in the bottom-fifth for consumption of those items.
Of note, when the researchers looked just at men, the highest consumers of red and processed meats had a 62 percent higher stroke risk than men who ate the least.
The consumption of more eggs was linked to a 41 percent greater risk of haemorrhagic stroke, a less common type of stroke that is caused by a ruptured blood vessel in the brain.
Only red meats were tied to ischemic strokes, the most common kind.
One limitation of the study is that researchers only had data on protein intake at two points in time, which the authors acknowledge might fail to account for changes in eating habits over the years.
Dr Jennifer Dearborn-Tomazos, a neurology researcher at Yale University School of Medicine, noted that because the study was based on observation only and didn’t randomly assign some people to eat red meat while others abstained, it isn’t possible to determine how diet changes might help reduce the risk of future strokes.
It’s possible, for example, that people who eat a lot of red meat also do other things that increase the risk of strokes, like not eating enough vegetables, Dearborn-Tomazos, who wasn’t involved in the study, told Reuters.
Even so, the study findings linking red meat to stroke risk after accounting for how much fat, carbohydrates and fibre people consumed supports traditionally held beliefs that red meat and saturated fats may increase the risk of cardiovascular disease, she said.
Meanwhile, Dr Haring offered some consolation.
“It’s ok to eat red meat, preferably lean red meat,” he said, “as long as you limit the amount.”