Study Links Diet to Stroke Risk

Overview of Stroke Types and Global Impact

A recent study has highlighted specific foods that may lower the risk of both ischemic and hemorrhagic strokes. In 2013, stroke was the second leading cause of death and the third leading cause of disability worldwide. A stroke disrupts blood flow to the brain, which can result in paralysis or even death. There are two primary types of stroke: ischemic, caused by a blood clot obstructing circulation, and hemorrhagic, which occurs when a blood vessel ruptures in the brain, resulting in blood loss. The incidence of stroke has risen over the past seven years, underscoring the urgent need for prevention.

Previous Research Limitations

While dietary factors have long been associated with stroke risk, prior studies had not specifically examined which foods correlate with ischemic versus hemorrhagic strokes. A recent extensive study conducted in Europe has begun to address this gap, revealing that certain foods may be more closely linked to one stroke type than the other. The findings were published in the European Heart Journal.

Study Design and Participant Information

The research recruited 418,329 men and women from 1992 to 2000 across nine European countries, including the United Kingdom, Sweden, Spain, Norway, the Netherlands, Italy, Greece, Germany, and Denmark. Participants completed questionnaires detailing their medical history, dietary habits, lifestyle choices, and socio-demographic information at enrollment. The researchers monitored the participants for an average of 12.7 years to assess the relationship between diet and stroke risk. By the conclusion of the study, there were 1,430 cases of hemorrhagic stroke and 4,281 cases of ischemic stroke.

Examined Food Groups

The dietary questionnaire focused on various food categories, including:
– Meat and meat products: red meat, processed meat, poultry
– Fish and fish products: white fish, fatty fish
– Dairy products: milk, yogurt, cheese
– Eggs
– Cereals and cereal products
– Fruits and vegetables
– Legumes
– Nuts and seeds
– Dietary fiber: total fiber, and fiber from cereals, fruits, and vegetables

Foods Reducing Ischemic Stroke Risk

The study found that increased consumption of fruits, vegetables, dietary fiber, and dairy products was associated with a lower risk of ischemic stroke. Notably, greater reductions in risk were linked to fruits and vegetables, as well as dietary fiber. Specifically, a daily increase of 200 grams of fruits and vegetables resulted in a 13% risk reduction, while an additional 10 grams of dietary fiber per day led to a 23% decrease in risk.

Foods Increasing Ischemic Stroke Risk

Conversely, the study indicated that consuming an additional 50 grams of red meat daily was associated with an increased risk of ischemic stroke.

Foods Decreasing Hemorrhagic Stroke Risk

Similar to ischemic stroke, the consumption of fruits, vegetables, dietary fiber, and dairy products correlated with a lower risk of hemorrhagic stroke.

Foods Increasing Hemorrhagic Stroke Risk

Interestingly, the consumption of eggs was linked to a heightened risk of hemorrhagic stroke. Specifically, for every additional 20 grams of eggs consumed daily, the risk increased by 25%. For context, a standard large egg weighs approximately 60 grams.

Conclusion and Future Research Directions

While the study establishes a connection between diet and stroke type, it acknowledges the need for further investigation. The research, despite its large sample size and comprehensive nature, only captured dietary data at a single point in time and did not account for subsequent dietary changes or other health conditions. Additionally, the influence of cholesterol and blood pressure on stroke causation remains unclear.

Ultimately, the findings support existing European dietary guidelines, emphasizing the importance of increasing fruit, vegetable, and fiber intake.

References

– Study of 418,000 Europeans finds different foods linked to different types of stroke. EurekAlert!. https://www.eurekalert.org/pub_releases/2020-02/esoc-so4022020.php. Published 2020. Accessed February 28, 2020.
– Tong T, Appleby P, Key T et al. The associations of major foods and fibre with risks of ischaemic and haemorrhagic stroke: a prospective study of 418 329 participants in the EPIC cohort across nine European countries. Eur Heart J. 2020. doi:10.1093/eurheartj/ehaa007.