By Karen Collins, M.S., R.D.N., C.D.N., F.A.N.D., Environmental Nutrition Newsletter
More than 21,000 U.S. women may expect a diagnosis of ovarian cancer in 2015, making it the fifth most common cause of cancer death among women. Ovarian cancer often has no symptoms at early stages, so the disease is generally advanced when diagnosed, with only a 45 percent rate of five-year survival.
That makes prevention and early detection especially important. We already know that women should avoid tobacco and consult their healthcare provider about screening. But what about diet?
The Internet is filled with recommendations for “superfoods” that supposedly fight ovarian cancer. Research on ovarian cancer and diet may make big headlines, but it’s important that your diet be based on what overall research shows, rather than random studies.
Unfortunately, there’s little research-backed support for eating habits that reduce the risk of this disease; your best-odds diet strategy should be created within the context of reducing overall cancer risk.
Here’s the bottom line on four diet tips to protect against ovarian cancer that have made the headlines:
1. Don’t worry about dairy.
Dairy foods have been blamed for increased risk in some headlines, but overall research does not show that limiting consumption or changing particular choices offers protection. Some studies suggest that lactose, the natural sugar in dairy products, changes levels of ovary-related hormones; others question dairy fat.
However, a major report from the American Institute for Cancer Research (AICR) concluded that data was too limited to show any link between ovarian cancer and lactose or any dairy products. Another major analysis published in Nutrition and Cancer shortly thereafter reached the same conclusion.
There’s no benefit to going overboard, but since dairy products (and the calcium they provide) reduce risk of colorectal cancer, it’s OK to include them in your diet.
2. Soy foods are OK.
Minimally processed soy foods, such as tofu, soymilk, soynuts and edamame, provide fiber and many nutrients, including compounds called isoflavones. In cell and animal studies, these compounds can slow cancer cell growth and prevent tumor formation.
Several population studies in Asia link lower risk of ovarian cancer to greater soy or isoflavone consumption, although studies in Europe and the U.S. show no link, perhaps because Western diets are very low in soy intake. And studies have suggested that you may gain more benefit from including soy earlier in life.
While the evidence isn’t strong enough to prove definitive ovarian cancer protection from soy, you can feel good about enjoying soy foods as a healthful swap for red meat.
3. Boost vegetables.
Plant foods should always be part of a diet to lower cancer risk. Cruciferous vegetables, such as cabbage, broccoli, cauliflower and kale, contain unique compounds called glucosinolates that show special anti-cancer effects in cell and animal studies. A few large population studies link less ovarian cancer to greater intake of these cruciferous vegetables, though some recent studies showed no benefit.
It’s possible that interactions with genes mean some people benefit more than others. While we await more research, it’s a smart idea to eat a wide variety of vegetables, including cruciferous choices.
4. It’s tea time.
This plant-based beverage contains polyphenol compounds, such as epigallocatechin gallate (EGCG), widely studied for health-promoting potential. In cell and animal studies, green tea’s EGCG seems to inhibit ovarian and some other cancers.
Small human studies suggest that tea may promote the body’s antioxidant defenses, yet overall, large population studies have failed to find that tea is linked with ovarian cancer.
More research is needed to understand how genetics and other factors may be involved. For now, tea–green or otherwise–remains an excellent no-calorie beverage choice, although evidence does not support use of concentrated supplements of its ingredients.
WEIGHT AND OVARIAN CANCER
Of all the diet-related factors regarding ovarian cancer risk, the only factor that the AICR found with a significant relationship is excess body fat. Overweight and obesity increase levels of hormones, as well as chronic inflammation that can contribute to cancer development. What to do?
Studies show that neither low-carb nor low-fat diets offer advantages for consistent weight control. Instead, create a long-term lifestyle with nutrient-rich foods that allow you to fill up without excess calories. Common-sense steps like healthy portion sizes, limiting sweets and keeping active complete the picture.
BEST DIET TO REDUCE OVERALL CANCER RISK
You can prevent 1 in 3 of the most common cancers with healthy eating, exercise and a healthy weight. To reduce your overall cancer risk, the AICR advises:
1. Maintain a healthy weight.
2. Move more. Be physically active for at least 30 minutes every day.
3. Choose foods lower in calorie density. Fill up on foods with fewer calories (and more fiber and nutrients) per bite. Avoid sugary drinks.
4. Eat a variety of plants: vegetables, fruits, whole grains and beans.
5. Limit red meat to no more than 18 ounces per week. Avoid processed meats, such as bacon and sausage.
6. If you drink alcohol, do so in moderation: no more than one drink per day for women, two for men.
7. Limit salt usage and foods processed with salt.
8. Eat a balanced diet rather than relying on supplements.
To learn more, visit: www.aicr.org/reduce-your-cancer-risk/
(Reprinted with permission from Environmental Nutrition, a monthly publication of Belvoir Media Group, LLC. 800-829-5384. www.EnvironmentalNutrition.com.)