Should Your Daughter Eat Soy?
New research says yes — a diet rich in tofu, tempeh and other sources of natural soy can lower her risk of breast cancer
If you have a daughter, bring out the chopsticks. According to a growing body of research, a childhood diet that includes tofu and other soy-rich stars of Asian cuisine may help head off breast cancer in adulthood.
One reason may be that girls whose diets include soy tend to enter puberty later, says Louise Greenspan, MD, associate clinical professor of endocrinology at the University of California San Francisco School of Medicine and coauthor of “The New Puberty: How to Navigate Early Development in Today’s Girls.” Late-onset puberty is linked to a lower risk of breast cancer.
Soy contains phytoestrogens, compounds found in a variety of plant foods that may work like estrogen in the body. In adults their effect could be worrisome; some data suggests they may increase the risk of breast cancer. But it’s a different story for young girls, says Greenspan. “The theory is that exposure to phytoestrogens before puberty changes the breast to be more ‘resistant’ to estrogen later." Puberty, she adds, is marked by the beginning of breast development and not, as many people think, a girl’s first period.
The best soy sources
Not everyone — and especially not every kid — is a fan of tofu and miso soup. But don’t rely on soy-based veggie burgers, hot dogs or “chicken” nuggets, says Greenspan. These typically are made from soy protein isolates, which may not have the breast-protective effects of natural soy. Soy protein isolates are also found in energy bars, so read labels carefully.
Better yet, go for natural soy products that are less processed. The best choices, with kid-friendly serving suggestions:
- Tofu. Use it in stir-fries or add it to tuna and green salads. Give it to your baby when she starts to eat finger foods.
- Tempeh. This fermented form of tofu is less bland than regular tofu and works well as an entrée (sautéed with a sauce) or with beans in chili.
- Soy milk. It's great in smoothies and on cereal.
- Edamame. Add these soybeans (shelled) to salads, or heat and serve them as a veggie side. In the pod, roasted edamame makes a yummy appetizer.
Other ways to head off breast cancer
While the news about soy is exciting, breast cancer is a complex disease, and there’s more than one way to lower the risk. Set up your daughter with these good habits. (They’ll lower your risk, too.)
- Favor fruits and veggies. Be sure to include ones that are rich in carotenoids, nutrients that give carrots, sweet potatoes, apricots and other produce their bright orange hue. A 2012 Harvard study found that women who had higher blood levels of carotenoids enjoyed a lower risk of breast cancer.
- Steer clear of sugar-sweetened beverages. They’re a big contributor to being overweight, which alone is a significant risk factor for breast cancer. A recent study also found that soda and other sugary drinks are linked to early-onset puberty.
- Get moving. Physical activity has been proven to lower the risk of breast cancer. Some research shows that exercise during adolescence is particularly beneficial.
- Limit alcohol. You may know that drinking has been linked to breast cancer in older women. It now turns out that adults who drink heavily or binge on alcohol are at especially high risk. When she’s old enough, include this fact when you talk to your daughter about alcohol.