Teenagers who consume a poor diet high in soft drinks, red and processed meats and low in vegetables may be at increased risk of developing breast cancer, a new study has warned.
Researchers collected data from about 45,204 women who had completed a food frequency questionnaire in 1998, about their diet during high school, when they were between 33 to 52 years of age.
“Because breast cancer takes many years to arise, we were curious whether such a diet during the early phases of a woman’s life is a risk factor for breast cancer,” said Karin B Michels, professor at University of California, Los Angeles (UCLA) in the US.
Adult diet was assessed first using a food frequency questionnaire in 1991, when participants were 27 to 44 years, and then every four years after that.
Each woman’s diet was given an inflammatory score using a method previously developed that links diet with inflammatory markers in the blood.
During 22 years of follow-up, 870 of the women who completed the high school food frequency questionnaire were diagnosed with premenopausal breast cancer and 490 were diagnosed with postmenopausal breast cancer.
Researchers then divided the women into five groups based on the inflammatory score of their adolescent diet, those in the highest score group had a 35 per cent higher risk for premenopausal breast cancer relative to those in the lowest score group.
When the same analysis was done based on early adulthood diet, those in the highest inflammatory score group had a 41 per cent higher risk for premenopausal breast cancer relative to those in the lowest score group.
A diet low in vegetables and high in sugar-sweetened and diet soft drinks, refined sugars and carbohydrates, red and processed meats and margarine has been linked to high levels of inflammatory markers in the blood, according to Michels.
“Our results suggest that a habitual diet that promotes chronic inflammation when consumed during adolescence or early adulthood may indeed increase the risk of breast cancer in younger women before menopause,” said Michels.
The study was published in the journal Cancer Epidemiology, Biomarkers and Prevention.