According to a recently published meta-analysis from China, people with diets higher in protein - especially from fish - are less likely to have a stroke than those who consume less protein in their diets.
Globally, stroke is one of the most common causes of disability and death. Many health experts believe that nutrition can be an effective strategy in the prevention and management of stroke.
A meta-analysis is a way of statistically contrasting and combining results from different studies to identify patterns among study results, sources of disagreement among those results, or other interesting relationships that become obvious in the context of multiple studies.
The amount of protein that led to the reduced risk in this particular meta-analysis was moderate - no more than 20 grams per day. According to the study authors, larger studies are needed before definitive recommendations can be made, but they say the evidence so far is compelling.
This meta-analysis looked at all of the available research on the relationship between proteins in the diet and stroke risk. Seven studies with more than 250,000 participants - who were followed for an average of 14 years - were included.
Participants with the highest amount of protein in their diets were 20 percent less likely to develop a stroke than those with the lowest amount of dietary protein. These results were compensated for other factors that could have affected the risk of stroke, such as smoking and high cholesterol.
Overall, for every additional 20 grams per day of protein that people consumed, their risk of stroke decreased by 26 percent.
The study authors state that if everyone's protein intake were at this level, it would lead to more than 1.4 million fewer deaths from stroke each year worldwide, along with fewer incidents of disability from stroke.
Previous studies looking at the effects of diet on stroke risk have also similarly concluded that the percentage of daily protein intake was lower in patients who suffered strokes compared to those who didn’t.
Note that this meta-analysis does not support increased consumption of red meat, which has been associated with increased stroke risk. Two of the studies were conducted in Japan, where people eat less red meat than westerners do and more fish, which has been associated with decreased risk of stroke.
In other words, these results also indicate that stroke risk may be reduced by replacing red meat with other protein sources such as fish. Interestingly, the reduced risk of stroke was stronger for animal protein than vegetable protein.