A stroke hits almost 800,000 people each year in the U.S. That means someone somewhere in America has a stroke every 40 seconds, and every four minutes someone dies from it.

Why is stroke so prevalent, and can you do anything to reduce your risk?

According to research published in The Lancet Neurology, the prevalence comes from epidemics of obesity, elevated blood sugar, chronic inflammation, and high blood pressure — and for some, a diet low in omega-6 fatty acids.

In the U.S., however, people often get too many omega-6s from meat, vegetable oils, and eggs compared to omega-3s from fatty fish and flaxseed. And that can also raise the risk of heart disease.

The good news is that the study found 84% of strokes are linked to modifiable risk factors — many of them directly in your control. An unhealthy body mass index, elevated blood glucose, drinking a lot of sweetened beverages, and overexposure to high outdoor temperatures, plus lack of activity, are big risks you can reverse.

Achieving a healthy weight by eating a plant-based diet that avoids added sugars, red and processed meats, and highly processed foods lowers your blood glucose and blood pressure. And dealing with increasingly hot temperatures by avoiding exercise outdoors midday, staying hydrated, wearing sunscreen and sun-shielding hats, and staying in air conditioning also reduces stroke risks.

More tips: Add regular physical activity and read Dr. Mike's book "The Great Age Reboot."