Will It Save My Life?
From red wine to Kombucha, are superfoods actually healthy?
Parsing the nutritional doublespeak about health foods—red wine fights cancer! But not if you drink too much!—can be a nightmare. So CHOW looked into 10 supposed superfoods to see just how healthy they really are.
The claim: This blueberry-size Amazonian fruit (pronounced ah-SAH-ee) is peddled mostly in juice form. It’s loaded with antioxidants, and allegedly has antiaging properties.
The proof: One of the first studies of açaí found that extracts of the berry reduced the growth of leukemia cells in the lab by up to 86 percent. It’s got healthy amounts of fiber, amino acids, oleic acid, and a superdose of antioxidants—more than most fruits, including pomegranate. So will a bottle of juice a day make you smarter and healthier? That’s “a moving target,” says food scientist Stephen Talcott. “If you consume any amount, technically you are getting certain benefits in your diet.”
2. Green Tea
The claim: It fights cancer, obesity, and heart disease.
The proof: Only the last claim has credence. An 11-year study of 40,000-plus Japanese men and women found that drinkers of five or more cups a day had a 16 percent lower risk of mortality and a 26 percent lower risk of cardiovascular disease than those who drank less than a cup a day. It failed to lower cancer-related deaths, however, even though in lab experiments it does limit the size and growth of cancerous tumors. Both green and black teas contain antioxidants, but green tea contains more, probably because it’s less processed.
3. Dark Chocolate
The claim: The flavonoids—compounds with antioxidant properties—that chocolate contains are thought to keep cells healthy and less susceptible to conditions like cancer and heart disease. Dark chocolate’s also got mood-boosting tryptophan.
The proof: In a recent 44-person study, a daily dose of dark chocolate, roughly equivalent in size to a Hershey’s Kiss, lowered blood pressure among adults (on average, systolic blood pressure went down nearly three points and diastolic decreased by almost two points). But the calories and fat in chocolate won’t do your heart much good, so limit your doses to about an ounce a day, and choose chocolate with no less than 70 percent cocoa for more flavonoids and less fat.
4. Red Wine
The claim: Has antiaging properties and helps prevent cancer.
The proof: Like green tea and dark chocolate, red wine contains flavonoids. It may also have some additional cancer-fighting properties, thanks to the natural antioxidant resveratrol, found mainly in red wine because it comes from grape skins. In lab tests, resveratrol has been shown to interfere with the growth of cancer cells, and a Harvard study found that for men, moderate consumption of red wine led to a 52 percent lower risk of prostate cancer. By moderate, they mean two five-ounce glasses a day for men, one for women—not exactly dinner-party quantities. Any more and you lose the antioxidant effects.
The claim: Better for you than dairy; helps lower cholesterol.
The proof: In 2006 the American Heart Association reversed its recommendation of taking soy supplements or eating soy to lower the risk of heart disease, because studies showed it had little effect on bad cholesterol. Now soy is being blamed for everything from goiters to dementia, but none of these claims are substantiated. Studies have shown it might increase the risk of breast cancer in premenopausal women, leading the American Cancer Society to warn survivors not to take soy supplements. (Still others have claimed—with less scientific backing—that soy makes kids gay.) Many dietitians, though, consider soy foods like tofu, with its polyunsaturated fat, fiber, vitamins, and minerals, a healthy replacement for meat. Just stick to soy as food—not as a supplement—in modest amounts.
The claim: The caffeinated beverage is full of antioxidants that provide health-protective benefits.
The proof: A new study from Finland shows that coffee may increase the risk of hypertension, but Harvard researchers found it reduced the risk of type 2 diabetes by more than 50 percent for men and nearly 30 percent for women who drank six or more cups a day. Coffee drinkers may also be at lower risk of Parkinson’s, colon cancer, liver cirrhosis, and gallstones. Three cups of coffee contain as much fiber as a raw apple. Its diuretic effects are mild, and easily compensated for by drinking water. And while coffee’s effect on cardiovascular health is still unclear, caffeine consumption is no longer thought to lead to osteoporosis, as long as you get adequate calcium elsewhere (like from your café au lait).
The claim: A descendant of the world’s first photosynthetic life form, this blue-green algae, usually sold in supplement form or in premixed smoothies, is believed to be a rich source of nutrients. Adherents say that it fights fatigue, anxiety, and depression; promotes weight loss; and enhances immunity.
The proof: It’s a significant source of protein, B vitamins, vitamin E, and antioxidants. A 2005 study found that taking two grams a day of spirulina helped hay fever sufferers. And a 1995 study involving tobacco-chewers with precancerous mouth lesions showed that 45 percent of those who took a gram of spirulina daily for one year experienced a complete regression, compared to just 7 percent in the control group.
The claim: Kombucha is a bacteria and yeast culture, mixed with sweetened, brewed tea and fermented into a vinegary-tasting, lightly carbonated beverage. It’s drunk by people who believe it can help fight cancer, aid in weight loss, and even restore hair color.
The proof: “There is no scientific evidence that Kombucha is healthy,” says GT Dave, maker of GT’s Organic Raw Kombucha, “but there is scientific evidence that the ingredients contained in [raw] Kombucha are healthy.” That’s true. Raw Kombucha is essentially organic brewed tea and probiotics—beneficial bacteria that promote good digestion. But some dietitians will recommend drinking only brews like Kombucha Wonder Drink that have been pasteurized, which wipes out all bacteria, good and bad, and stops the fermentation process that can continue in raw Kombucha, upping the alcohol content to 2 percent or more—a concern for those who don’t want even that small amount in their brew. Still, since the FDA found no evidence of contamination in unpasteurized Kombucha teas fermented under sterile conditions—in other words, commercially bottled brews—the only Kombucha you should be really wary of is the one brewed at home.
9. Raw Milk
The claim: Drinkers believe it aids poor digestion, arthritis, asthma, skin conditions, and allergies.
The proof: Pasteurization is the only safeguard against harmful pathogens like E. coli, salmonella, and listeria, which is borne out by studies on illnesses from raw milk and raw milk cheese—45 outbreaks between 1998 and May 2005. However there are also many miracle stories of allergy, eczema, and arthritis sufferers who find relief once they start drinking raw milk, perhaps because the enzymes, proteins, and beneficial bacteria haven’t been killed by pasteurization. But since no clinical studies support these turnarounds, the general advice from food scientists like Rob Ralyea at Cornell’s Northeast Dairy Foods Research Center is to only drink raw milk if you’re aware of the risks and aren’t immune-compromised. Pasteurization does diminish the vitamins in milk by 10 to 20 percent, according to Ralyea and the FDA, but they’re added back, along with vitamin D, which is barely present in raw milk but is increasingly seen as an important nutrient.
10. Raw Food Diet
The claim: Uncooked fruits, vegetables, nuts, and seeds are undoubtedly packed with nutrients—some of which can get lost when heated. Some people say cooking food above 120 degrees Fahrenheit kills the enzymes that act as catalysts for chemical reactions in the body: namely, digestion.
The proof: Aside from the fact that this flies in the face of basic physiology—we produce our own digestive enzymes—there are some reasons to keep the burner on. “Not all fruits and vegetables are better raw,” says American Dietetic Association spokesperson Keri Gans. Cooked tomatoes contain more cancer-fighting lycopene, and carrots more beta carotene, by some virtue of the cooking process that makes their nutrients more absorbable. “The only benefit of a raw food diet is that people eat more fruits and vegetables on it,” adds Gans. (Read more about a raw diet.)
Nicole Davis is a freelance writer and the editor of the newsletter Brooklyn Based.