Red meat – but not other types of protein – is linked to an
increased stroke risk, and the odds go up the more meat people eat, a recent
study suggests.

Researchers analyzed data on about 11,000 middle-aged people who
didn’t have other risk factors for strokes such as diabetes or heart disease,
and followed half of them for around 23 years.

The people in the study 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
wasn’t associated with any added risk.

Even though 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 Center
at the University of Wurzburg in Germany.

“It’s ok to eat red meat – preferably lean red meat – as long as
you limit the amount,” Haring said by email.

To assess the link between protein consumption and stroke risk,
Haring and colleagues reviewed data from diet questionnaires completed by U.S.
residents aged 45 to 64 starting in 1987 and followed them through 2011 to see
how many people had strokes.

The study participants were divided into five groups based on
how much protein and what type they consumed. For instance, the bottom-fifth
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.

Compared to participants with high protein consumption, those
who ate less protein on average at the start of the study were more likely to
be black, current smokers and less likely to have high school diplomas or a
regular exercise routine. 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.

During a median follow-up of 22.7 years, there were 699 strokes
among 11,601 participants.

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.

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.

Eating more eggs was linked to a 41 percent greater risk of
hemorrhagic strokes, a less common type that is caused by a ruptured blood
vessel in the brain. But 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.

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, noted Dr. Jennifer Dearborn-Tomazos, a neurology researcher at Yale
University School of Medicine in New Haven, Connecticut.

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, said by
email.

Even so, the study findings linking red meat to stroke risk
after accounting for how much fat, carbohydrates and fiber people consumed
supports traditionally held beliefs that red meat and saturated fats may
increase the risk of cardiovascular disease, she said.