We've heard the advice time and time again: "Healthy eating habits start young." After reading a new study's findings on teen girls, the words never rang more true.
It has been known that high-fiber diets can increase fertility, help with constipation, lower cholesterol levels and help control blood sugar levels (most notably, it can also reduce the risk of diabetes and heart disease). But there's another benefit, too. According to the large-scale study published in Pediatrics and led by researchers from Harvard's T.H. Chan School of Public Health, teen girls who eat a lot of fiber-rich foods are significantly less likely to develop breast cancer later.
In 1991, a group of 90,534 women (ages 27 to 44 at the time) were surveyed about their eating habits and continued to complete detailed questionnaires every four years. In 1998, the completed a survey about their diet during high school.
Teens who ate the highest amount of fiber during high school (an average of 28 grams per day) had a 24 percent lower risk of developing breast cancer pre-menopause and 16 percent lower risk overall when compared to those who ate low levels of fiber (an average of 14 grams per day).
Each additional increase of 10 grams of fiber per day during adolescence reduced the risk of breast cancer by 14 percent.
"Having the recommended 25 to 30 grams of fiber daily would decrease the risk by 30 percent and potentially even greater with higher fiber intake," says lead author Maryam Farvid. "Women are doing themselves a huge favor in terms of breast cancer prevention if they increase the amount of dietary fiber intake earlier in life rather than later."
But how? Kimberly Blackwell, a breast cancer specialist at the Duke Cancer Center, writes, "There is longstanding evidence that dietary fibers may reduce circulating estrogen levels [through changes in the gut microbiome]." High estrogen levels in the blood are strongly linked with breast cancer development.
A caveat of the study though is that the women were in their 30s and 40s when asked to recall what they ate during high school, meaning there could be "recall bias" and their memories may not have been as reliable.
Nevertheless, Blackwell said, "It is reasonable for pediatricians to encourage a high-fiber diet and include decreasing breast cancer risk as one of the potential benefits."
So go nuts with fiber and try to include it in your and your kids' meals when you can. Think fruits (e.g., pears, raspberries, apples, avocados), vegetables (e.g., broccoli, green peas, beets, carrots), whole grains (e.g., whole wheat pasta, brown rice, oatmeal) and, of course, nuts.