The best-known risk factors for Parkinson's disease tend to be things we can't change -- being male or over age 65, for example. But like most diseases, Parkinson's is complicated, and over the past decade or so, researchers have uncovered some surprising factors you can control to cut your risk of developing the disease.
Coffee to Reduce Parkinson's Risk
Can coffee actually be good for you? Several studies suggest so. In one, researchers who analyzed data from the Honolulu Heart Study found a startling decrease in Parkinson's disease incidence among men who drank the most coffee. In this study, 8,004 Japanese-American men enrolled between 1965 and 1968, and researchers followed the group for 30 years. They found that those who didn't drink coffee were two to three times more likely to develop Parkinson's than coffee drinkers. When they compared nondrinkers to the heaviest coffee drinkers (more than 28 ounces a day back in the 1960s), the nondrinkers were five times more likely to develop the condition.
What to do: There's growing evidence that moderate amounts of coffee can help prevent other health problems, including diabetes, liver damage, gallstones, and Alzheimer's. So if you're a java junkie, go ahead -- your coffee vice might actually do you some good. About 200 to 300 milligrams per day -- that's one to three 8-ounce cups, depending on the coffee and how it's brewed -- should be enough to provide a benefit. Each 1-ounce shot of espresso gives you about 50 to 75 milligrams. Keep in mind that large amounts of caffeine can also cause dependence and withdrawal headaches and can contribute to bone loss. Some people who are sensitive to caffeine may have spikes in blood pressure or heart arrhythmias. As with most things, moderation is best.
Boost Your Vitamin D to Reduce Parkinson's Risk
Although there's not yet a clear cause-and-effect relationship, several studies have found that a majority of people with early Parkinson's are deficient in vitamin D. In a study from 2011, researchers checked levels of 25-hydroxyvitamin D in stored blood samples and found that nearly 70 percent of Parkinson's patient samples had low levels (in this case, under 30 ng/mL, or nanograms per milliliter) at the start of the study. As time passed, the patients' disease progressed but their vitamin D levels didn't go further down, so experts believe it's not likely that vitamin D supplements would help someone already diagnosed with Parkinson's. But having healthy levels of vitamin D is certainly a good thing -- and it might act as "insurance" against Parkinson's if you're at high risk.
What to do: The sunshine vitamin is essential for bone health and may also protect against high blood pressure, cancer, and other conditions. Most adults need 600 International Units (IUs) of vitamin D per day; those over age 70 need 800 IU. Oily fish and fortified dairy products are good food sources. The sun's UV rays stimulate vitamin D production in the body, but it's an unreliable source in many parts of the world or at certain times of year.
How do you know if you're getting enough vitamin D? It's becoming more common for doctors to test for vitamin D (though not everyone agrees that's necessary), so at your next visit you might want to ask. Ideal levels of 25-hydroxyvitamin D range between 50 and 100 nmol/L (nanomols per liter). As always, check with your doctor before you take any supplements -- vitamin D accumulates in the body, and it's possible to get too much.
Add Berries to the Mix to Reduce Parkinson's Risk
In Parkinson's disease, certain types of nerves in the brain get damaged. One source of damage in the body is from what scientists call oxidative stress (think of it as the body's equivalent of oxygen attacking iron and forming rust). There's some evidence that this oxidation process is involved in Parkinson's disease. Antioxidants are chemicals that fight this process and protect cells from damage.
Turns out that berries have a lot of antioxidants, so researchers at Harvard School of Public Health decided to take a closer look. Berries -- and possibly other brightly colored foods -- may protect against Parkinson's. The team mined data from the large ongoing Health Professionals Follow-Up Study and found that men who ate the most flavonoids were 40 percent less likely to develop Parkinson's disease, compared to men who ate the lowest amounts. Flavonoids are a large family of compounds with antioxidant properties found in many foods, including berries, tea, citrus, soy, onions, and herbs. When researchers looked closer, they found that anthocyanins, a class of flavonoids that give berries their bright red and purple colors, helped both men and women lower their risk of Parkinson's.
What to do: Add at least a serving a day to your daily diet to get the flavonoid benefits. One easy way: Toss a handful in your cereal bowl each morning. Dried blueberries are available year-round, or you can freeze or dehydrate your own during peak season. Berries are delicious and packed with vitamins, so there's really no downside. They're also a good source of several B vitamins and vitamin C (another antioxidant).
Fight Inflammation With Ibuprofen to Reduce Parkinson's Risk
Many diseases are now thought to involve inflammation, the immune system's response to any injury to the body. (We're most used to seeing it as redness and swelling around a wound, but it happens inside the body as well, in arteries and organs.) Even Alzheimer's and diabetes are now linked to inflammation, so researchers at Harvard Medical School decided to see if anti-inflammatory medicines would lower the risk for Parkinson's.
Using data from more than 130,000 patients enrolled in the Nurses' Health Study and the Health Professionals Follow-Up Study, they found that people who used ibuprofen regularly (for unrelated concerns) had a whopping 40 percent lower risk of developing Parkinson's compared to those who didn't take any anti-inflammatory drugs. Other similar drugs, such as aspirin, didn't have the same effect.
What to do: If you're at high risk of developing Parkinson's and are already taking an anti-inflammatory medicine, you might want to ask your doctor whether you should be using ibuprofen. Like all drugs, ibuprofen has its pluses and minuses, so you'll want to be sure it's the right choice for you.
Stop Drinking Milk to Reduce Parkinson's Risk
At least three studies have shown that dairy raises the risk of Parkinson's disease, although the effect seems stronger in men and comes mainly from drinking milk rather than taking in other forms of dairy. It's unknown whether milk itself contains something that can raise the risk among some people, or if a contaminant might be to blame.
In the most recent study, people enrolled in the large ongoing Cancer Prevention Study II were contacted in 2001 about their health, and researchers at Harvard School of Public Health identified those who had developed Parkinson's disease. They then went back and checked the participants' eating habits from the questionnaires filled out when they enrolled in 1992. Compared to men who drank the least milk (less than 3 ounces per day), men who drank the most milk (more than 12 ounces daily) were 1.7 times more likely to have developed Parkinson's. This is in line with findings from previous studies.
What to do: As long as you can get your calcium from other sources -- leafy greens, tofu, and bony fish such as sardines -- it's probably a good idea to give up milk.
Avoid Pesticides to Reduce Parkinson's Risk
Researchers have long known that agricultural workers have higher rates of Parkinson's disease than the general public, and they suspected that pesticide exposure was at least partly to blame. A 2009 study showed that this is in fact the case. Researchers at the University of California at Los Angeles looked at residents of California's agriculture-heavy Central Valley and found that people who had lived within 500 meters (about a quarter mile) of fields sprayed with the pesticides paraquat or maneb had a 75 percent higher risk of Parkinson's. More worryingly, people who had been diagnosed before age 60 (and had therefore been exposed as children or young adults) had much higher rates of Parkinson's compared to people who hadn't been exposed; their risk doubled with exposure to one pesticide and increased fourfold with exposure to both.
What to do: To be safe, it's best to avoid all sources of pesticides, including pesticide residue on foods. Buy organic whenever possible and wash all produce thoroughly -- organic or not -- with lots of water and a produce wash (special food-safe soaps that remove many types of chemicals, waxes, and bacteria). If you grow your own food, avoid chemical pesticides.