Food expert Michael Pollan says most supplements ‘generally don’t work.’ But he takes this one daily

Over half of Americans take at least one supplement, according to the CDC. But Michael Pollan, who has taught a MasterClass on intentional eating, written multiple food-related books, and released a food system documentary, Food, Inc. 2, out today, says we should instead be receiving our vitamins from our diet.

"Our bodies evolved to get nutrients from food, not from pills. So it's no wonder that supplements generally don't work, unless you have a very specific deficiency,” Pollan told Business Insider.

Pollan says if you’re considering taking a supplement, to eat more vegetables instead. Specifically, he suggests eating plants from a family of cruciferous vegetables called brassicas, or cole crops, because of their plant compounds that can help lower risk of cancer, heart disease, and other age-related diseases. These vitamin- and mineral-rich plants include broccoli, cabbage, kale, cauliflower, collard greens, and Brussels sprouts.

There’s a group of chemicals inside these vegetables called glucosinolates that can be thanked for their bitter flavor. It’s also likely to be the reason why people who eat these veggies have lower rates of certain forms of cancer. But putting the compound that forms when these chemicals break down into a pill isn’t the same as consuming the food directly, says Pollan.

"There are things we don't understand about the structure of food, and the relationship of the chemicals within the food that is very important," he says. Supplements also aren’t regulated by the U.S. Food and Drug Administration (FDA) for safety and effectiveness.

However, there is one supplement Pollan says he takes daily: a multivitamin.

“But that’s it,” he says.

Why take a multivitamin?

The appeal to multivitamins is that it’s a one-size-fits-most pill.

“While individual nutritional needs vary from person to person depending on age, sex, health status, and lifestyle, many multivitamin supplements provide nutrients that play crucial roles in various physiological processes to prevent deficiencies that would otherwise cause health problems,” Jamie Lee McIntyre, RD previously told Fortune.

Most multivitamins contain vitamins A, D, E, K, C, and B; calcium; magnesium; iron; zinc; selenium; manganese; and chromium, says McIntyre.

Multivitamins can help supplement those with dietary restrictions, like vegetarians, with vitamins and minerals they might be missing from just their diet. They aren’t a cure-all, though. Combining a balanced diet with exercise is the best way to fight against harmful diseases and manage weight, but adding a daily multivitamin into the mix is not a bad idea—just do your research and consult a doctor first.

“Overall, while multivitamins can be a convenient way to support overall health, they should be used judiciously and in conjunction with a healthy lifestyle and dietary habits,” says McIntyre.

This story was originally featured on Fortune.com