BODY-WEIGHT AND COLON-CANCER

In 1994, there were approximate to 160 000 new cases of colon cancer i n the United States with 58 000 fatalities, making this form of cancer the second most common cause of cancer deaths. Up to 50% of colon can cers may have a strong inherited factor, but in the remaining cases, d iet and lifestyle factors are thought to play essential roles in the c arcinogenic process. Various epidemiologic studies have examined the r elation between obesity and colon cancer. The largest prospective stud y of 750 000 men showed that mortality from colorectal cancer was sign ificantly elevated in men who were greater than or equal to 40% overwe ight. No such increase was found in women. Subsequent studies reported conflicting results. Overweight is likely a surrogate. Other risk fac tors include a high-fat, energy-dense diet; inadequate consumption of fruit and vegetables; and lack of physical activity, which have been a ssociated with a high incidence of colon cancer.