Don't worry, eating your greens is still a good thing.

plant based diets heart disease
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There are myriad reasons to embrace Meatless Monday or even go meat-free for life: with a veggie-heavy diet, you're more likely to consume less saturated fat and more fiber, you'll probably lower your cholesterol, and you can even reduce you risk of heart disease—or so many researchers thought, until a recent study suggested otherwise.

The study, published this week in the Journal of the American College of Cardiology, shows that while plant-based diets are often recommended to reduce a person's risk of heart disease, some plant based actually increase you heart-disease risk.

Here's why: previous research, which showed a decreased risk of heart disease with a plant-based diet, neglected to weigh plant foods differently. In other words, the benefits of snacking on shelled edamame was weighed the same as eating white rice or sipping on a sugary soda (hey, high-fructose corn syrup is plant-based, after all)—foods and drinks that can increase your risk of cardio-metabolic disease. This latest study by the American College of Cardiology took into account the benefits and drawbacks of plant-based foods, and analyzed plant-based diets in three different categories: a plant-based diet that emphasized plant food and reduced—but did not eliminate—animal products; a plant-based diet that focused on healthy plant foods such as whole grains, fruits and vegetables; and a plant-based diet that that relied on less healthy plant foods, such as refined grains and potatoes.

After reviewing the diets of more than 73,000 women and placing them in the three diet categories, the researchers found that those women who followed the healthy plant-based diet reduced their risk of heart disease, while those who subscribed to the less healthy plant-based diet increased their risk of heart disease. In fact, during the researcher's follow-up, 8,631 participants developed coronary heart disease.

Ambika Satija, Sc.D., the study's lead author, concluded that, "it's apparent that there is a wide variation in the nutritional quality of plant foods, making it crucial to take into consideration the quality of foods in a plant-based diet." That's something most of us probably already knew—but it's news that even foods we might consider healthier than, say, a fatty sausage slathered in ketchup, can hurt our hearts' health, too. So the next time you whip up a Meatless Monday meal, or prepare your vegetarian grocery list, make heart-healthy choices by skipping refined grains, starches, and sugary sweets, even if they do come from plants.