Is height the key to cancer?
This article first appeared in the St. Louis Beacon: November 21, 2008 - A population of Ecuadorian dwarfs has never seen even one case of diabetes or cancer. A story in the news recently, and again this week, directs attention to the possibility that height may be linked to the development of cancer.
Research has shown that increased height is associated with a higher incidence of cancer, particularly in the cases of breast and prostate cancer (two cancers strongly linked with hormonal causes). And other studies have demonstrated that energy intake during childhood is linked with the later incidence of cancer.
Adult height has always been a marker of childhood nutrition and health, and most gains in height before puberty are due to increases in leg length. Scientists have hypothesized that leg length can subsequently be used as a way to determine any link between adult height and cancer. Two theories emerge:
- Longer legs suggest a longer or more rapid growth period and would point to an earlier puberty and a prolonged exposure to adult levels of hormones. This is similar to risk of breast cancer increasing with earlier menarche (first menstrual period) and later first pregnancy, two factors which lead to greater, overall exposure of estrogen.
- Childhood diet patterns, also associated with adult height, may hold an influence on other hormones implicated in inflammatory processes. These may include insulin-like growth factor-I, which may increase the risk of cancer later in life. Insulin-like growth factor-I's link to cancer is supported by recent studies results that strongly associate it with risk of breast and prostate cancer.
Call for Research
More diet-cancer research in the news this month tells suggests that a lower-calorie diet and exercise program can reduce a postmenopausal woman's risk of breast cancer. The results from scientists at the University of Texas at Austin were presented earlier this month at the American Association for Cancer Research's Seventh Annual International Conference on Frontiers in Cancer Prevention Research.
"One of the few breast cancer modifiable risk factors is obesity," said lead author Leticia M. Nogueira, Ph.D., a research graduate assistant at the University of Texas. "Our study may provide a good scientific basis for medical recommendations. If you're obese, and at high risk for breast cancer, diet and exercise could help prevent tumor growth."
Another study presented at the conference suggests that while regular exercise can decrease overall risk of cancer in females, this is only so when also getting enough sleep. A lack of sleep appears to undermine the cancer-protective effects of exercise, the researchers say.
Race for the Cure
For the first time, researchers have identified DNA hormone receptor structure. A new UVA Health System study, published in the October 29 issue of Nature, says the discovery may provide a pathway for designing more effective drugs for the treatment of hormone receptor positive cancers. These would include certain breast cancers. If scientists knew exactly what hormonal cancer cells thrive on, they may be able to stop the spread in its tracks.
Read the research
For more on cancer, visit the ACS website:
Dr. Cindy Haines is managing editor of Healthday-Physician's Briefing and president of Haines Medical Communications Inc., a full-service medical communications and consulting firm. As a board-certified family physician, Haines is well-versed in all areas of health care, with particular interest in fitness, nutrition, and psychological health.