Western nutrition and the insulin resistance syndrome: A link to breast cancer

Abstract

Objective: The incidence of breast cancer in the Western world runs parallel to that of the major components of the insulin resistance syndrome Ð hyperinsulinaemia, dyslipidaemia, hypertension and atherosclerosis. Evidence is reviewed that the growth of breast cancer is favoured by speci®c dietary fatty acids, visceral fat accumulation and inadequate physical exercise, all of which are thought to interact in favouring the development of the insulin resistance syndrome. Design: Clinical, epidemiological and experimental studies linking breast cancer risk with evidence of insulin resistance and its concomitants, were searched for in the MEDLINE database since 1985. Results: Clinical and epidemiological evidence suggests that both breast cancer and the metabolic disorders comprising the insulin resistance syndrome are polygenic and multifactorial in origin. Experimental evidence suggests that hyperinsulinaemia and its concomitants can increase the promotion of mammary carcinogenesis and the mechanism is likely to involve increased bioactivity of insulin-like growth factor 1 (IGF-1). Case-control and cohort studies have shown that higher serum levels of IGF-1 are associated with increased breast cancer risk. Pharmacological agents which lower IGF-1 concentrations are under clinical trial for breast cancer prevention. Conclusions: Nutritional and lifestyle modi®cations that improve insulin sensitivity may not only decrease a tendency to atherosclerosis but also reduce breast cancer risk in women. In addition to a reduced fat intake, the dietary regimen might involve a reduced n-6/n-3 ratio of polyunsaturated fatty acids and should be associated with avoidance of obesity and regular physical exercise. Interventions to decrease breast cancer risk in ®rst-degree relatives of breast cancer patients need to begin at an early age.

Intakes of plant foods, fibre and fat and risk of breast cancer – a prospective study in the Malmö Diet and Cancer cohort

“…Fibre might modulate the enterohepatic recirculation of oestrogens leading to increased faecal excretion of oestrogens and reduced levels of circulating bioavailable oestrogen (Gerber, 1998). Breast cancer has been suggested to be associated with the insulin resistance syndrome (Kaaks, 1996;Stoll, 1999); a fibre-rich diet could slow digestion and absorption of carbohydrates and influence plasma insulin response (Slavin, 2000). Minor constituents, like antioxidants, phytate and especially phyto-oestrogens, present in fibre-rich foods, might be biologically active components (Gerber, 1998;Cohen, 1999).…”

Hormone replacement therapy and breast carcinoma risk in Hispanic and non‐Hispanic women

“…Steroid and metabolic peptide hormones are likely to play critical roles in breast carcinogenesis for Hispanic and non-Hispanic white women. 34,35 Breast carcinoma risk is increased greatly among women who have higher cumulative exposure to estrogens and other steroid hormones. 35 Metabolic hormones, particularly insulin and insulin-like growth factor , may act synergistically with steroid hormones in stimulating breast cell proliferation, serving as carcinogenic promoters of carcinogenesis.…”

Metabolic syndrome affects breast cancer risk in postmenopausal women: National Cancer Institute of Naples experience

“…[4][5][6][7] Physical inactivity and saturated fatty diet contribute to the spread of overweight and obesity. [7][8][9] Central body fat and insulin resistance in overweight and obese women appear to be crucial in determining MS. 10 MS, according to the National Cholesterol Education Program (NCEP) Adult Treatment Panel III (ATP III), can be defined as the presence of at least three of postmenopausal women show the highest incidence of breast cancer in the female population and are often affected by metabolic syndrome.…”