Risk factors like smoking, diet, and genetics are known to contribute to the odds of developing cancer, but researchers in Britain have found another risk — height. According to research published in the medical journal Lancet Oncology, tall women have a higher risk of getting a cancer diagnosis than their shorter sisters. Here, a brief guide:
How did researchers discover this link?
By combing through the data in the Million Women Study, a health survey of 1.3 million British women conducted between 1996 and 2001, researchers found that for every four inches of height above five feet, women had a 16 percent higher risk of developing cancer. The increased odds of a taller woman getting cancer were consistent "regardless of her birth year, socioeconomic status, alcohol consumption, physical activity level, and other factors typically linked to cancer risk," says Tara Thean in TIME.
What kind of cancer did these tall women develop?
The women in the survey were diagnosed with many different types of cancer, but researchers found that tall women were at the greatest risk for skin cancer (melanoma), kidney cancer, colon cancer, non-Hodgkin lymphoma, and leukemia. Also, the "risk of breast cancer, the most common cancer in the study, increased 17 percent with every four inches of height," says Marissa Cevallos in the Los Angeles Times.
Why does height increase cancer risk?
There are a number of theories, but no one is certain what causes the association between height and cancer risk. The study authors speculate that because taller people have more cells, there's a greater chance of cellular mutations that can lead to malignancies. Growth hormones are another possible culprit: They "increase cell growth and rate of division, and inhibit cell death," says lead researcher Dr. Jane Green, as quoted by CNN. "Both of these might be relevant to cancer."
Is there anything tall women can do?
Since nobody can change their height, experts advise following common-sense strategies for preventing cancer and other illnesses, like exercising, eating well, and not smoking. After all, says Denise Snyder of Duke University at MedPage Today, "two-thirds of cancer risk is attributable to lifestyle factors such as diet and physical activity."