Summary

We looked at the associations between plant-based diet quality and the risk of complete, ischemic, and hemorrhagic stroke to see whether a healthy plant-based diet is linked to a lower risk of stroke.

The study included 73,890 women in the Nurses' Health Study (NHS; 1984 to 2016), 92,352 women in NHSII (1991 to 2017), and 43,266 men in the Health Professionals Follow-Up Study (1986 to 2012) who were free of cardiovascular disease and cancer at the start. The overall plant-based diet index (PDI), the healthful PDI (hPDI), and the unhealthful PDI were used to assess the consistency of plant-based diets (uPDI). Participants who recorded none or less than one serving of meat or fish per month were classified as vegetarians, while those who reported more than one serving per month were classified as non-vegetarians. Ischemic and hemorrhagic strokes were classified based on medical records.

Results: A total of 6,241 stroke cases were reported during the follow-up period (including 3,015 ischemic and 853 hemorrhagic strokes). The hazard ratios (HRs) for total stroke among participants with the highest PDIs were 0.94 (95 percent confidence interval 0.86 to 1.03) for PDI, 0.90 (0.83 to 0.98) for hPDI, and 1.05 (0.96 to 1.15) for uPDI, compared to participants with the lowest PDIs. Participants with the highest hPDI had a slightly lower HR for ischemic stroke (0.92 [0.82 to 1.04]) but no stable relationships for hemorrhagic stroke. Despite the limited number of cases, we found no connection between a vegetarian diet and total stroke (1.00 [0.76 to 1.32]).

Conclusions: Those who followed a healthy plant-based diet had a lower risk of total stroke.