When Beauty Food Backfires

Dark chocolate

Many women jumped for joy when dark chocolate was deemed a health food thanks to its disease-fighting antioxidants. The dark stuff is not only good for your heart (it helps lower blood pressure), but it can also boost your mood—and your beauty. “When you have chocolate it increases serotonin [the feel-good hormone] and you temporarily feel better,” explains Kirkpatrick.

How it can backfire: Just because the sweet treat is good for you, that’s no excuse to inhale a whole bag of it in one sitting—especially since chocolate is high in saturated fat and sugar. “Chocolate tastes so good that it is easy to over-consume,” says Glassman. “Eating too many calories, sugar and fat can lead to increased risk of diabetes and obesity.”

How much to eat: It’s less than you think—around two or three ounces per week (or about four to six small squares of a dark chocolate bar), according to Kirkpatrick. In order to reap dark chocolate’s heart-health benefits, the label has to say it contains 70 percent or more cocoa content.

More: The Deal with Dark Chocolate

Fruit

Whether your preference is for bursting blueberries, juicy peaches or scrumptious strawberries, fresh fruit is downright delicious and can help tame your sweet tooth. It’s also good for you: Fruit is loaded with disease-fighting antioxidants, as well as fiber—all in a nutrient-dense, low-calorie package. “Berries are especially beneficial,” says Kirkpatrick. “The darker the hue, the more antioxidant benefits it has.”

How it can backfire: Although fruit is a healthy, fiber-rich food, it also contains a lot of sugar (fructose) so it’s best not to go overboard. “Your pancreas will still need to pump insulin in order to metabolize fruit,” says Kirkpatrick, “and you can have real fluctuations of your blood sugar that can lead to inflammation.”

How much to eat: Aim to consume no more than five handfuls of fruit per day. To help you gauge the right portion size, think of your fist as one handful.

Oatmeal

Is there anything more wholesome than a hot bowl of oatmeal? It’s full of heart-healthy soluble fiber, which reduces your low-density lipoprotein (LDL), the "bad" cholesterol. For people looking to lose weight, oatmeal is a great breakfast choice because it’s so filling, making you less likely to reach for that donut to tie you over until lunch.

How it can backfire: People often eat oatmeal because it’s good for them, but not everyone likes the bland taste. Research shows that can cause them to load their oatmeal with sugar so it’s more palatable—which adds up to extra pounds, according to study author Wansink. What’s more, Wansink found that oatmeal eaters also consumed well beyond the recommended portion size of a half-cup or rewarded themselves with additional calories in the form of a mid-morning snack.

MORE: The Scoop on Oatmeal

How much to eat: About a half-cup of dry steel-cut oats (the instant kind is convenient but full of added sugar, while the slow version is healthier and keeps you feeling fuller longer, according to Kirkpatrick). “If plain oats are reminiscent of eating cardboard to you, try adding spices like cinnamon, nutmeg, pumpkin spice or flavored extracts like vanilla,” suggests Glassman. You can also sprinkle on some sliced almonds or walnuts for a satisfying crunch and a heart-healthy boost—or just choose another health breakfast option that you actually like.