If you’re a woman and getting at least 30 minutes a day of activity, that means a lower risk of colorectal cancer. Now a study published today suggests that women who exercised as teens for even an hour a week have a lower risk of dying from cancer in middle age and older compared to teens who weren’t active at all.
These women are also more likely to live longer overall, the study suggests, whether they exercised as adults or not.
The study included almost 75,000 Chinese women who were part of the Shanghai Women’s Health Study. The women were 40 to 70 years old and they had answered questions about their lifestyle habits currently and decades earlier.
After an average of 13 years, the researchers looked how many of the women had died overall, and whether the cause of death was from cancer or cardiovascular disease.
The women who reported participating in an exercise program as teens at least once a week — translating to 1.3 hours a week or less on average — and over had a lower risk of dying during the study compared to those who didn’t exercise. This is when the researchers took into account whether the teens ate healthy, their weight and age.
The women who reported exercising as teens had lower BMI (a measure of body fatness) and were eating more fruits and vegetables. They were also more likely to exercise regularly as adults.
So the researchers also took into account whether these teens were active as adults, along with other known adult risk factors such as BMI. And most of the links still held. Women who exercised as teens 1.3 hours a week or less had a 16 percent lower risk of dying from cancer and a 15 percent lowered risk for death from all causes during the course of the study compared to those who reported not exercising as teens. Exercising as adolescents for more than 1.3 hours a week linked to a lower risk for death from all causes.
Teens who were on sports teams also had a lower risk of dying from cancer and heart disease.
The authors then tried to tease apart mortality risk depending upon when the women exercised: as teens, adult or both. They found that exercising as both a teen and adult was associated with the greatest reductions in dying during those 13 years.
In this study, physical activity measure during adolescence did not include walking or biking to and from school or other leisure-time activities. That could means the links between teen’s physical activity and mortality are underestimated. Recalling exercise habits from decades past could have also led to errors, the authors note.
But this study joins a growing list of evidence suggesting that what children and teens weigh and their lifestyle habits can influence their health decades later. We’ve written about a few of these studies here and here.
For ideas on how to help kids be more active and eat healthier, we have them at AICR Healthy Kids.
This study was funded by the National Institutes of Health