What makes berries so healthy?

DEAR DOCTOR K:

You often list berries as one of the most nutritious foods. It’s berry season, and my wife wants to buy lots of them, but they’re a little expensive. So, I’d like to know what makes them so healthy. Call me a skeptic.

DEAR READER:

I know, I know, I keep repeating it’s the berries. But that’s because it’s true. And if the expense is an issue, consider the expensive foods you buy that are definitely unhealthy. I don’t need to list them — you know what they are.

Berries are perhaps the easiest way to follow the fruit part of the “eat more fruit and vegetables” advice you hear all the time, including from me. Berries naturally come in bite-sized portions. They’re sweet but have a low calorie count, partly because they contain a lot of water. If you don’t need to watch your calories — yes, there are people who are born thin — you can “pig out” on them. (Just don’t sprinkle much sugar on them.)

For one thing, berries contain a lot of fiber. A cup of raspberries contains 8 grams of fiber, which is more fiber than you’ll find in a serving of oatmeal.

For another, berries contain vitamins (C and a little bit of E, because of the seeds). They also contain many less well-known but powerfully beneficial nutrients. One of the most important are substances called anthocyanins. These substances give berries their vivid red, blue and purplish colors. Anthocyanins are antioxidants, which keep oxygen ions and other unstable molecules from damaging DNA, interfering with cells’ energy-making machinery, stirring up inflammation in the body and having a variety of other harmful effects.

Anthocyanins are concentrated in the skin of berries (as well as other fruits). In general, the more intense the color, the higher the anthocyanin content. So blueberries and blackberries usually contain more anthocyanins than strawberries or raspberries. And wild berries have more antioxidants than their larger, paler, domesticated relations. Raspberries also contain a substance called ellagitannin, which imparts flavor and has antioxidant properties that add to the effects of anthocyanins.

You may have heard that antioxidants in pill form, such as certain vitamin supplements, generally have not been proven to benefit your health, as many had hoped they would. However, antioxidant-rich foods definitely are good for you. Berries are one important example.

Be sure to wash berries right before eating them. That’s because berries can harbor viruses, bacteria and other pathogens that cause foodborne illnesses.

For me, a good way to start a day is with a bowl of fresh, delicious berries, mixed with French vanilla yogurt and coffee creamer with amaretto flavor. That’s a major part of breakfast every weekend (and often weekdays) at our place.

I had a patient who was a professional cook. She once chastised me for talking about how healthy certain foods were. “The point you should be emphasizing is that they are delicious, because they are. The fact that they’re also healthy is the icing on the cake.” She’s right. And berries are healthier than the icing on the cake!

(This column is an update of one that ran originally in June 2013.)