These colorful fruits help give
your heart a rosy glow.
By Linda Melone
Whoever said “good things come in small packages” may have been thinking of berries. From açai berries to blueberries, cranberries, gooseberries and raspberries, these tiny fruits pack a wallop of powerful nutrients, including those responsible for keeping your heart functioning optimally. Antioxidants, micronutrients and fiber found in berries have all been associated with reduced cardiovascular disease risk.
What’s more, their eye-catching hues make berries a favorite fruit for people of all ages, says Lisa Ellis, MS, RD, a registered dietitian with a private practice in Westchester County, New York. “The range of colors has a practical benefit as well—the different colors reflect various nutritional properties of each kind of berry,” she adds. Anthocyanin, for example, an antioxidant found in many berries, is in proportion to the intensity of the red color found in fruits such as strawberries. In fact, levels of anthocyanin can range from 2 to 4 grams in a kilogram serving, rising as the fruit ripens.
Adding berries to your diet may be the tastiest and easiest way to boost heart health. Most varieties are low in calories and sodium, and high in fiber as well as antioxidant vitamins C and A, which protect cells from inflammation-promoting free radical damage.
Simply adding berries to your diet three times a week is enough to decrease heart attack risk, according to a British investigation based on the ongoing Nurses’ Health Study II. Blueberries and strawberries contain high levels of healthful compounds; in an analysis published in Circulation (1/15/13), anthocyanin in particular has been found to help dilate arteries, offset the buildup of arterial plaque and provide other cardiovascular benefits. The research group discovered that among 93,600 women ages 25 to 42, those who ate the most blueberries and strawberries experienced a 32% reduction in heart attack risk compared with women who ate berries once a month or less.
The abundance of polyphenols in berries helps to lower certain inflammatory states, mostly those related to metabolism of fats and glucose (blood sugar), says Nicole Weinberg, MD, a cardiologist at Providence Saint John’s Health Center in Santa Monica, California. “The more inflammation in your body the higher your glucose level and the higher your cholesterol. So if you can lower some of that inflammation you’ll then modify risk factors that can create organ damage as far as the heart is concerned,” she explains.
A version of resveratrol called pterostilbene, found in blueberries, has been shown to have similar benefits. Pterostilbene induces the activity of an antioxidant called superoxide dismutase already present within the body, says natural products researcher Ryan Dellinger, PhD, who adds, “It’s more bioavailable.” In a 2012 University of Mississippi study, published in Hypertension, giving people who had high cholesterol pterostilbene for eight weeks lowered both systolic (top number) and diastolic (bottom number) blood pressure.
Blueberries are particularly beneficial in helping repair cells and in preventing damage that can occur with aging and exposure to all the toxins in our environment on a daily basis, says Malissa Wood, MD, cardiologist with the Massachusetts General Hospital Heart Center in Boston. “Heart cells are different in that they don’t turn over like other cells, such as skin and the lining of the gastrointestinal cells,” explains Wood, who serves as a physician spokeswoman for the American Heart Association’s Go Red For Women campaign (goredforwomen.org). “If you damage a heart muscle cell it does not get replaced with another cell. You’re born with all the heart cells you’ll ever have.”
She says that although the heart doesn’t produce new cells, antioxidants in berries can “feed” the heart muscle and keep it healthy.
Wood says berries appear to reduce lipid peroxidation, a process similar to the rusting of metal, in which cholesterol changes into an unhealthy form. “And they can also help with endothelial function, which means they help the blood vessels relax,” she adds.
Berry benefits go beyond the heart. A 2010 study presented before the American Chemical Society stated that eating fruits such as blueberries, strawberries and açai berries may keep the aging brain healthy. Scientists believe berries act as a natural “housekeeper” by cleaning up and recycling toxic proteins linked to mental decline and age-related memory loss.
The high fiber content of berries also contributes to their heart health benefits. Fiber enables you to rid your body of cholesterol that could otherwise be absorbed by your arteries, says Weinberg, who adds, “The more fiber in your diet the more efficiently you can rid your body of cholesterol.” Researchers at Britain’s University of Leeds have found a link between higher fiber intake and reduced risk of coronary heart disease (BMJ 12/13).
Raspberries are a particularly good source of fiber; dietitian Ellis says, “Just one cup provides 25% to 30% of our daily fiber needs (recommended intake is 25 to 30 grams). Dietary fiber also links to lower LDL (bad cholesterol), lower blood pressure in people with high blood pressure and an overall lower risk of heart disease.” Raspberries, loganberries and blackberries all contain 8 grams of fiber per cup, while blueberries contain 4 grams.
The fact that berries contain both soluble and insoluble fiber augments their health-boosting properties. Insoluble fiber promotes healthy digestion, while “soluble fiber has been shown to act as a ‘sponge’ to help clean up bile, so it works by reducing levels of bad cholesterol,” says Rene Ficek, RD, lead nutrition expert at Seattle Sutton’s Healthy Eating, a meal-preparation service.
Other heart-protective nutrients found in berries include folate, potassium and vitamin C. The American Heart Association recommends 400 micrograms of folate a day and “a serving of strawberries provides almost 100 mcg,” says Ficek. Strawberries are also high in potassium: one cup provides more potassium than half a medium banana, a fruit noted for its potassium content.
Açai berries may also help reduce cholesterol levels, according to a study in the journal Nutrition (7-8/10). In this study, açai reduced the effects of a high-cholesterol diet among rats. Goji berries, another exotic fruit, have been used in traditional Chinese medicine for thousands of years. A study shows goji’s antioxidants may help prevent or reduce free radical-related conditions when used for longer than 30 days (Nutrition Research 1/09), thus lowering heart disease risk.
Berries in the Kitchen
While it is always preferable to buy fruit fresh, you can freeze berries or purchase frozen berries any time of the year, says Ellis, who recommends buying organic berries when available. ”Berries are smaller fruits and tend to collect more surface pesticides than other fruits due to berries’ surface-to-fruit ratio,” she says. “In addition, pesticides can be easily absorbed through their thin skins.” For best quality, look for intact berries without signs of bruising or staining of the container.
Once you get the berries home, it’s best to eat them within three days. Store raspberries, strawberries and blueberries in a sealed container in the refrigerator.
Blackberries deteriorate quickly and should be eaten on the day of purchase, although they can be stored uncovered in the refrigerator for a day or so. Cranberries keep for up to a week in the refrigerator when stored in a plastic bag or covered container and also freeze well. To freeze, arrange berries in a single layer, then stack the layers into plastic bags before freezing; firmer berries such as cranberries and blackberries do not require layering.
Try these tips for incorporating more berries into your diet:
Whirl them into smoothies
Stir them into whole-grain hot or cold breakfast cereals such as oatmeal
Substitute mashed berries in place of jelly for classic PB & J sandwiches or as a fruity spread on whole-grain waffles or pancakes
Blend berries with a small amount of orange juice and a pinch of cloves to make a healthy glaze for chicken breasts
Stir a serving of frozen berries into yogurt or cottage cheese for an instant chilled treat
Toss them on top of salads drizzled with raspberry vinaigrette
Stir a handful into your favorite bran muffin recipe (or other plain quick bread)
Eat out-of-hand for a simple quick snack (to avoid mold, do not rinse until immediately before eating)
If you’re looking for a flavorful way to keep your heart healthy, make berries a regular part of your meal planning.
Strawberry & Honey Protein Shake
Try this shake as a snack or for post-workout replenishment.
1 1/2 cups fresh or frozen strawberries
2 ripe kiwi, peeled and quartered
1 cup low-fat milk
2 scoops plain whey protein
1 tsp pure vanilla extract
1-2 tsp honey, or to taste
Place all ingredients in a blender and process until smooth. Serve immediately.
Makes 2 servings. Reprinted with permission of Linda Melone.