TikTok Video Mangles American Cancer Society Breast Cancer Estimates

Breast cancer in American women under 50 increased gradually from the mid-1990s through 2019, with a somewhat steeper rise starting in 2016. The rate of female breast cancer also rose slowly in older women from the mid-2000s through 2019.

Researchers say these changes were likely at least partly due to changes in when people begin having children and, for older women, increasing body weight. Being overweight after menopause or having children later in life increases the risk of breast cancer.

Breast cancer incidence fell for all women and women under 50 in 2020, likely because disruptions to health care appointments during the pandemic led to...