Sex differences in the association of obesity and colorectal cancer risk

Abstract

Epidemiological research has convincingly shown that obesity increases colorectal cancer (CRC) risk, with generally stronger associations observed in men than in women. Evidence from the past several years has demonstrated a divergent pattern between men and women regarding the weight changes throughout life or timing of obesity for CRC risk. For men, weight gain later in life appears to be an important risk factor for CRC that mostly accounts for their generally strong association between adult body mass index and CRC risk. For women, however, early life obesity seems to be more important than adult weight gain in determining CRC risk. A knowledge of these sex patterns may have implications on better understanding colorectal carcinogenesis and may further improve prevention efforts for CRC.

Adolescent body mass index and risk of colon and rectal cancer in a cohort of 1.79 million Israeli men and women: A population‐based study

“…Because of similar magnitudes of risk of CRC associated with BMI in men and women, the authors concluded that the findings did not support a sex difference in the association between BMI and CRC risk, as had been hypothesized. 2 However, these results are entirely compatible with the sex difference concerning the association between obesity and CRC as proposed. A key feature of the new study by Levi et al 1 was the predominance of earlyonset CRC, with a median age of 49.4 years at the time of CRC diagnosis.…”

“…A key feature of the new study by Levi et al 1 was the predominance of earlyonset CRC, with a median age of 49.4 years at the time of CRC diagnosis. As we summarized in our commentary, 2 based on data from the Nurses' Health Study and the Health Professionals Follow-up Study, adolescent body fatness was found to be a stronger CRC risk factor among women than among men. 3 Furthermore, a Mendelian randomization analysis of obesity-related genes 4 that are associated with early-onset obesity 5,6 found a stronger association with CRC in women compared with men.…”

Association of Dietary Inflammatory Potential With Colorectal Cancer Risk in Men and Women

“…30,31 Also, early life obesity seems to be the primary risk factor for colorectal cancer in women, whereas for men, adult weight gain rather than early life, predominates. 32 This pattern may be due to differences in sex hormones, given that in men and postmenopausal women, estrogen is produced mainly in fat tissue. 33 In women, a high estrogen-testosterone ratio is protective against colorectal cancer risk but in men it may have an adverse effect.…”

Dietary Patterns and Colorectal Cancer Risk: a Review of 17 Years of Evidence (2000–2016)

“…For example, higher adiposity strongly predisposes men to higher risk of rectal cancer compared to women [77–79]. Also, early life obesity seems to be a more important risk factor for colorectal cancer in women, whereas for men, adult weight gain rather than early life, predominates [80]. This pattern may be due to differences in sex hormones, given that in men and postmenopausal women, estrogen is produced mainly in fat tissue [81].…”