Alternative Medicine

PROSTATE CANCER PREVENTION

By Michael Castleman

Prostate cancer is the Rodney Dangerfield of malignancies. It gets no respect, or at least less than it deserves. The disease is the most frequently diagnosed cancer in men--more than twice as many diagnoses each year as male lung cancer. Its statistics are similar to breast cancer--230,000 prostate cancer diagnoses this year [2004] vs. 216,000 for breast cancer. Annual death rates are also on the same order of magnitude: 30,000 from prostate cancer, 40,000 from breast.
 
But unlike breast cancer, there are no Runs for the Cure of prostate cancer, no sense of national urgency. “Perhaps one reason,” muses William Dahut, M.D.
chief of the genitourinary and gynecologic research section at the National Cancer Institute (NCI), in Bethesda, Maryland, “is that prostate cancer is perceived as less tragic. It’s rare in men under 50, while breast cancer often strikes--and kills--women under forty.” And while virtually every breast cancer spreads and proves fatal if left untreated, prostate cancer usually remains in the gland. It becomes life-threatening only in a fraction of cases. Prostate cancer is diagnosed in almost 20 percent of men, but only 3 percent die from it. “Most men who develop prostate cancer die with it, not from it.” Dahut says.
 
Still, 230,000 diagnoses and 30,000 deaths a year is a major toll. Even if the death risk is small, it’s unnerving to be diagnosed with a potentially life-threatening disease. And treatment often leaves a man incontinent and with erection impairment.
 
The good news is that simple diet and lifestyle approaches reduce risk substantially. Preventive efforts are particularly important for those at high-risk:
 
* Men over 50. Rock star Frank Zappa died of prostate cancer at 52, but 70 percent of cases are diagnosed in men over 65.
 
* Men with a family history of the disease. Having a father or brother with prostate cancer doubles risk.
 
* African-American men. For reasons that remain unclear, African-Americans are 70 percent more likely than whites to develop prostate cancer.
 
“No matter what your risk,” says John Hibbs, N.D, a clinical professor of naturopathic medicine at Bastyr University, the naturopathic medical school near Seattle, “without bending yourself out of shape, you can reduce it by as much as 50 percent.”
 
Eat More Vegetables--Especially Tomato Sauce
 
Mom was right. The research shows that as fruit and vegetable consumption increases--especially vegetables--prostate cancer risk plummets. Fruits and vegetables are rich in antioxidant nutrients--among them, vitamins A, C, and E, and the mineral, selenium--that prevent the cell damage at the root of cancer (and heart disease, and other conditions). Recently, University of Hawaii researchers compared the diets of 3,237 men, half of whom had prostate cancer. The more vegetables and beans they ate, the lower their risk. Comparing those who ate the most and fewest vegetables, the men who ate the most had 35 percent less risk. A recent Canadian study agrees, showing that a diet high in green vegetables--salads, spinach--cut risk 46 percent. 
 
But the vegetable with the most prostate-protective buzz is tomatoes. They contain lycopene, one of the vitamin A family of antioxidant nutrients, collectively known as carotenoids. Recently, Yale researchers analyzed blood samples from 437 men with and without prostate cancer. Compared with the cancer sufferers, the healthy men had considerably higher blood levels of lycopene. The researchers calculated that having high blood-lycopene reduces risk 35 percent--and risk of aggressive, life-threatening disease a remarkable 63 percent. Many other studies agree that a diet high in tomato-based foods reduces prostate cancer risk, notably an analysis by a Harvard researcher showing that a two to four weekly servings of tomato foods reduces risk 35 percent and risk of metastatic prostate cancer 50 percent.
 
Fresh tomatoes in salads are a good start, but your best lycopene bet is tomato sauce. Lycopene survives the heating necessary to make sauce, Hibbs explains. Sauce also contains less water than fresh tomatoes, making it a more concentrated source of antioxidants. And processing tomatoes into sauce makes lycopene more available to the body.
 
But watch out for America’s favorite tomato-sauce food, pizza. The cheese and meats (pepperoni, sausage, etc.) largely cancel the tomato sauce’s benefits (see below). If you want pizza to reduce your risk of prostate cancer, opt for vegetable toppings and go easy on the cheese.
 
Supplement companies now offer lycopene pills--but the evidence favors food sources. University of Illinois researchers exposed animals to a chemical that causes prostate cancer, while feeding them one of three diets--a standard lab diet, or that diet with added lycopene or whole tomato powder.  Compared with the control group, the whole-tomato group was 26 percent less likely to die from prostate cancer. The lycopene group fared better than the controls, but not as well as the whole-tomato group, suggesting that other unpublicized nutrients in tomatoes also play a role in reducing prostate cancer risk. “Tomatoes contain many more carotenoids than just lycopene,” Dahut explains. “They all help.” Still, if you want a lycopene boost, or don’t like tomatoes, a supplement can help.
 
Supplement Selenium and Vitamin E
 
While fruits and vegetables contain antioxidant vitamin E and selenium, there are good reasons to supplement them. The selenium content of plant foods varies depending on the mineral content of the soil, so you may not get enough if your plants foods were grown in low-selenium soil. It’s hard to know, so it’s prudent to take a supplement. Selenium became a cancer-prevention celebrity in 1996 when a researchers at the University of Arizona gave a supplement containing 200 micrograms (mcg) a day to people with skin cancer in hopes of preventing recurrences. Ironically, after five years, the mineral had no effect on skin cancer risk, but compared with controls, the group that took selenium was an astonishing 65 percent less likely to develop prostate cancer. Other studies corroborate those results. A recent Harvard study showed that compared with men with low blood levels of selenium, those with the highest levels were 65 percent less likely to develop prostate cancer. “Many one-a-day supplements don’t contain 200 mcg of selenium,” Hibbs says. “For prostate cancer prevention, I recommend that amount.”
 
Vegetable oils are high in vitamin E, but processing removes much of it and cooking removes even more. Nuts, beans, and dark leafy greens also contain it, but even if you’re a vegetarian--and most Americans aren’t--you may not get enough to reduce risk of prostate cancer. Supplements help. Finnish researchers gave 29,000 men over 50 a placebo or a vitamin E supplement (50 mg/day). Six years later, the vitamin E group had 32 percent lower prostate cancer risk.
 
Eat Less Meat and Dairy
 
America’s cowboy heritage has made thick, juicy steaks seem manly. Not if you want to avoid prostate cancer. Studies from around the world show that a diet high in animal (saturated) fat--meats and whole-milk dairy products--is a major risk factor for prostate cancer. Compared with American men, who chow down on pepperoni pizza, bacon cheeseburgers, and Haagen-Dazs, native Japanese men eat a diet much lower in animal fat, and have a much lower risk of prostate cancer. But when Japanese men move to the U.S. and begin to adopt an American diet, their prostate cancer rate rises. U.S.-born Japanese-American men raised on an American diet loaded with saturated fat have a prostate cancer rate comparable to native white Americans. Comparing men who eat lots of red meat with those who eat little or none, many studies agree that a high-meat diet doubles or triples prostate cancer risk. 
 
Why does saturated fat raise risk? Three reasons, Hibbs says: Meat displaces plant foods from the diet, so you get fewer cancer-preventive antioxidants. Saturated fat increases blood levels of male sex hormones, which stimulate the growth of prostate tumors. And saturated fat contains compounds such as arachidonic acid that spur inflammation, which promotes the growth of tumors. “You don’t have to convert to vegetarianism,” Hibbs explains, “just eat lots of plant foods and keep it to modest portions of lean meats. If you eat meat, don’t grill it. Charring meats introduces more carcinogens.”  
 
Recently, Greek researchers tried to tease out the benefits of switching from an American-style diet to one low in saturated fat and high in plant foods. Switching, they concluded, would reduce prostate cancer risk a whopping 41 percent.
 
Eat More Fish
 
The omega-3 fatty acids in cold-water fish, such as salmon, are well known for reducing risk of heart disease. Recent research shows they also help prevent prostate cancer. In laboratory tests, marine fatty acids stop the growth of prostate tumor cells. In addition, in the American diet, fish typically substitute for meat. And fatty acids are anti-inflammatory, which also reduces risk of cancer. Harvard researchers tracked 48,000 American men for 12 years. Compared with those who ate fish less than twice a month, the men who ate it more than three times a week were 44 percent less likely to develop the disease.
 
Watch Your Weight
 
Plant foods are low in calories, while meats and whole-milk dairy items are high-calorie--and add pounds. So it should come as no surprise that obesity raises prostate cancer risk.  French researchers compared body mass index and prostate cancer risk in 194 men with the disease and 194 cancer-free controls. Obese men had 2.5 times the prostate cancer risk. “Excess body fat contributes to chronic inflammation, and tumor promotion,” Hibbs says.
 
Drink Soy Milk
 
Male sex hormones stimulate the growth of prostate cancer. Female sex hormones suppress it, which is why estrogen drugs are sometimes used to treat the disease. Soy foods contain plant versions of female sex hormones (phytoestrogens). Scientists speculate that a diet high in tofu helps explain Asian men’s unusually low rate of prostate cancer. Soy milk appears to be particularly protective. Researchers have followed the diet and health of 12,000 Seventh-Day Adventists since the mid-1970s, including their consumption of soy milk. Compared with those who drank no soy milk, men who did more than once a day were an astonishing 70 percent less likely to develop prostate cancer. This study has not been confirmed, so its results should be viewed with caution. Still, if you enjoy soy milk, drinking it may well reduce your risk.
 
Prevent Sexually Transmitted Infections
 
In women, infection with genital warts increases risk of cervical cancer. So researchers wondered if sexually transmitted infections (STIs) might increase risk of prostate cancer in men. Several studies show that a history of STIs, especially gonorrhea and syphilis, approximately doubles prostate cancer risk. It’s not entirely clear how STIs spur development of prostate cancer, but these infections cause inflammation, Hibbs explains. Beyond STI prevention, if you or your partner is nonmonogamous, this finding is another good reason to use condoms.
 
Hey, Babe, How About You and Me Prevent Prostate Cancer...
 
Men may try this line to coax women into bed, thanks to a new study by researchers at the National Cancer Institute, Johns Hopkins, and Harvard that linked increasing ejaculation frequency to lower risk of prostate cancer. The researchers followed 29,000 middle-aged men for eight years. Compared with those who reported seven or fewer ejaculations per month, the men who had 21 or more were 33 percent less likely to develop prostate cancer. This study agrees with some previous research, but contradicts other studies showing that increasing ejaculatory frequency is associated with greater prostate cancer risk. However, the new study involved many more men and followed them longer than previous research, so its results carry more scientific weight. Note to women who would rather not have sex: The study did not distinguish between ejaculations during partner sex or masturbation. If you’re not in the mood to help him prevent prostate cancer, suggest that he do it himself.
 
Similar controversy surrounds vasectomy and prostate cancer. A few studies suggest that vasectomy increases risk somewhat, but many others show no connection. “On balance,” Dahut says, “I don’t see real evidence that vasectomy increases risk.”
 
Herbs: Promising
 
Last fall [2003], Columbia University researchers announced that a combination of 10 antioxidant/anti-inflammatory herbs kills prostate cancer cells. The product, Zyflamend, formulated by New Chapter, Inc. of Brattleboro, Vermont, contains: ginger, rosemary, oregano, turmeric, and green tea, among other herbs. The researchers added Zyflamend to culture dishes containing human prostate cancer cells. Three days later, 78 percent of the cancer cells were dead. To date, Zyflamend has not been studied in humans for prevention or treatment of prostate cancer. But it’s available at supplement and health food stores. Follow label directions.
 
“You can incorporate all the prostate-cancer prevention recommendations into your life, and still develop the disease,” Hibbs explains. “But preventive strategies cut risk by about half--and help prevent heart disease and other serious conditions. If you adopt the diet and lifestyle recommendations that reduce risk of prostate cancer, you’ll live a healthier life.”
 
 
Sidebar:
ALTERNATIVE APPROACHES TO
BENIGN PROSTATE ENLARGEMENT’
 
James Duke of Fulton, Maryland, is betting his prostate on the medicinal herb saw palmetto--and winning. The 75-year-old Ph.D. botanist who could pass for the brother of Kentucky Fried Chicken’s Colonel Sanders, is the former chief of the U.S. Department of Agriculture’s Medicinal Plant Laboratory in Beltsville, Maryland. Fifteen years ago, when Duke first experienced symptoms of prostate enlargement--decreased urine flow and nightly wake-ups to urinate--he wasn’t interested in the standard treatments, surgery that snips away overgrown prostate tissue, and prostate-shrinking drugs (Proscar). The drugs are 5-alpha-reductase inhibitors. They interfere with an enzyme that spurs prostate overgrowth. “Saw palmetto,” Duke explains, “is a natural 5-alpha-reductase inhibitor and it’s just as effective.”
 
Duke’s claim was put to the test in 1998 when European researchers compared saw palmetto (320 mg/day) against Proscar in 1,098 men. After 26 weeks, Proscar reduced symptoms 39 percent, saw palmetto, 37 percent. But the herb caused fewer side effects, notably less erection impairment and libido loss. “I take the dose used in that study,” Duke says, “a daily 320 mg.”
 
Several more recent studies corroborate saw palmetto’s safety and effectiveness. UCLA researchers concluded that the herb is “a safe, highly desirable option” for men with moderate prostate enlargement.
 
Another herbal treatment is African star grass, or pygeum. Minneapolis researchers analyzed six studies and found that compared with placebo treatment, men who took pygeum were more than twice as likely to report improved urine flow and fewer nighttime wakeups. The recommended dose is 100 mg/day.
 
Finally, pumpkin seeds, a traditional folk remedy for prostate enlargement, have been shown to contain compounds (cucurbitacins) that reduce prostate overgrowth. German researchers gave pumpkin seed extract to 2,245 men with prostate symptoms. Twelve weeks later, they reported significant improvement.
 
When Duke told his MD that he planned to treat his prostate saw palmetto, the doctor was taken aback. Now he’s a convert. “At my last checkup,” Duke says, “my doctor told me, ‘Just keep taking the herb.’ My doctor is nearing 60, and starting to experience prostate symptoms. Recently, he said he might try saw palmetto himself.”
 
San Francisco health writer is the author of 12 consumer health books, most recently Great Sex: A Man’s Guide to the Secrets of Total-Body Lovemaking. Six excerpts can be found at www.greatsexthebook.com.