By Rachel Johnson, Ph.D, M.P.H., R.D., September/October 2009
All my life I’ve been prone to motion sickness—not a good thing when your husband has a passion for sailing.
My mother, a nurse, used to give me ginger ale to settle my belly when I complained of nausea. Now I use ginger to calm my churning stomach when I’m sailing rough waters or flying on a bumpy plane.
I’m not the only one who’s thought of using a kitchen-based remedy to soothe symptoms. And interest in homegrown remedies may be on the rise. A government-sponsored survey reported that worries about the economy are driving more people to alternative remedies as they look for ways to save money on expensive doctor visits and prescription medicines.
How do we know which foods will truly help us feel better? I decided to find out what research says about some popular “kitchen cures.”
Scientific research shows that ginger may help control nausea related to pregnancy, surgical anesthesia and, yes, even sailing the high seas. In one study out of Denmark, consuming 1 gram of gingerroot reduced the severity of naval cadets’ seasickness. How does the spicy root alleviate queasiness? Ginger contains compounds called gingerols that, like anti-nausea medications, “help block serotonin receptors in the stomach,” says Suzanna M. Zick, N.D., M.P.H., assistant research professor in the Department of Family Medicine at the University of Michigan. (Serotonin, that famous “feel-good’ brain chemical, is also associated with vomiting.) Zick recommends steeping 1 to 2 grams of fresh gingerroot (1 gram is about the size of a quarter) in boiling water to make a tea or eating about 2 teaspoons of candied ginger. Don’t go overboard, Zick warns: consuming more than 6 grams of ginger in one sitting can irritate the stomach.
As for ginger ale: only a few companies use real ginger in their brews—and since most manufacturers don’t disclose amounts of ingredients it’s hard to know whether even those drinks have enough ginger to provide antinausea benefits, says Zick.
Drinking cranberry juice can help prevent urinary tract infections (UTIs), according to several studies. Cranberries contain compounds called proanthocyanidins that appear to keep harmful bacteria from sticking to the bladder. If you get more than three UTIs per year, says Ruth Jepson, Ph.D., R.N., senior research fellow in the Department of Nursing and Midwifery at the University of Stirling, Scotland, you might consider the proactive approach of drinking cranberry juice regularly. She recommends two (8-ounce) glasses a day. Dried cranberries may come in handy, too: one small study found that eating about 1⁄3 cup of sweetened dried cranberries daily may also help prevent UTIs. Don’t forget to account for the additional calories: each cup of unsweetened cranberry juice contains about 70 calories (140 for sugar-sweetened); 1⁄3 cup of sweetened dried berries has about 120 calories. Once a UTI develops, juice probably won’t help. “There is no clinical evidence that cranberry juice is effective in shortening the duration of a UTI or in alleviating the painful symptoms,” notes Jepson. Why do so many women swear it works? “The jury’s still out on that,” says Jepson, who speculates that consuming extra fluids may help flush out the harmful bacteria. So drinking plenty of plain old water may work just as well.
Better make it two cups. Studies show that 200 milligrams of caffeine—about the amount in 16 ounces of brewed coffee—does provide relief from headaches, including migraines. Exactly how caffeine relieves headaches isn’t clear. But scientists do know that caffeine boosts the activity of brain cells, causing surrounding blood vessels to constrict. One theory is that this constriction helps to relieve the pressure that causes the pain, says Robert Shapiro, M.D., Ph.D., associate professor of neurology and director of the Headache Clinic at the University of Vermont Medical School.
However, relying on caffeine long-term can backfire. When regular coffee drinkers miss their daily caffeine fix, this is often associated with a rebound increase in blood flow to the brain. Increased blood flow means increased pressure and, as a result, “withdrawal headaches” can occur. Shapiro counsels headache sufferers to limit caffeine intake and use it only to relieve headaches.
Our bodies normally play host to some “good” bacteria and some “bad” bacteria, along with a small amount of yeasts. “Good” bacteria help to keep yeast populations in check. When the number of beneficial bacteria drops, yeasts can start to take over, resulting in a yeast infection. A few studies suggest that eating yogurt—which contains “good” bacteria—may keep yeast under control. One study found that women who regularly ate yogurt had a healthier balance of bacteria and fewer infections. But other studies aren’t as promising—and none, so far, has found that eating yogurt provides any relief once an infection has developed.
Even so, if you’re susceptible to yeast infections, having a cup of yogurt every day can’t hurt. If nothing else, it’s a good source of protein and calcium. Look for brands that specifically advertise they contain live and active cultures, which ensures you’ll get the beneficial bacteria.
There’s intriguing evidence that taking omega-3 fatty acids in the form of supplements and cod-liver oil may help reduce flare-ups of rheumatoid arthritis (RA), an autoimmune disease that affects more than 1.3 million Americans. Omega-3 fatty acids work similarly to nonsteroidal anti-inflammatory medications, such as ibuprofen: they reduce the production of prostaglandins, hormone-like substances that cause swelling and pain (i.e., inflammation). And, while “the definitive study has yet to be done,” says John Hardin, M.D., chief scientific officer for the Arthritis Foundation, it’s “reasonable to assume” that the anti-inflammatory actions of omega-3s in supplements and cod-liver oil might also benefit people with osteoarthritis (OA), a much more common form of arthritis.
Could eating fish rich in omega-3s also help? Perhaps: one Greek study found that RA sufferers reported having less pain during Lent, when they followed Lenten rules to eat fish instead of meat. But beyond this circumstantial association, there isn’t any “real” evidence (e.g., clinical study results) that eating fish soothes arthritic aches. Still, Hardin and many of his fellow rheumatologists regularly tell patients that a diet that “leans more toward fatty fish” may help alleviate their pain. And even if it doesn’t end up reducing arthritis pain, eating fish—particularly fatty types, such as salmon—twice a week may help your heart.
I’m happy to know that when I turn to ginger for motion sickness or cranberry juice to prevent UTIs, I’ve got some scientific evidence standing behind me. But even in the absence of rigid scientific proof, I’m not opposed to trying the occasional food cure, if it sounds sensible and uses real foods in reasonable amounts. As the ancient Greek physician Hippocrates said, “Let food be your medicine, and your medicine be food.”
Rachel K. Johnson, an EatingWell Advisory Board member, is a professor and associate provost at the University of Vermont.