Women tend to outlive men. That’s just how it is. But a new study from the University of Wisconsin–Madison suggests that this wasn’t always the case. Both men and women born in the 19^th century had similar life expectancies—much shorter than men and women born in the 20^th century.

It wasn’t until the late 19^th century that men began dying earlier than women. What changed? Well, for one thing, smoking was more common among men than women in the late 1900s. And the researchers were also quick to point out that men generally ate more animal fat than women. Studies suggest that men born between 1950 and 1985 eat more meat, cheese, and other animal-based foods than women do. These fatty, cholesterol-laden foods contribute to obesity, diabetes, heart disease, and other life-threatening illnesses.

In other words, women tend to live longer than men because women tend to eat less meat. Studies suggest that people who eat little or no meat and lots of plant-based foods—which are cholesterol-free and contain phytochemicals, complex carbohydrates, fiber, vitamins, and minerals. and other healthful nutrients—tend to live longer than people who eat animal-based foods.

People can’t predict when or how they’ll die, but all of us, male and female, can improve our quality of life—and increase our chances of living a long time—by eating vegan foods rather than meat, eggs, and dairy products.