British Journal of Nutrition

Hormones and Metabolism

Testosterone, sex hormone-binding globulin, calculated free testosterone, and oestradiol in male vegans and omnivores

Timothy J. A. Keya1, Liane Roea2, Margaret Thorogooda2, John W. Moorea3, Graham M. G. Clarka3 and Dennis Y. Wanga3

a1 Cancer Epidemiology Unit, Imperial Cancer Research Fund, Gibson Building, Radcliffe Infirmary, Oxford OX2 6HE

a2 General Practice Research Group, Imperial Cancer Research Fund, Department of Community Medicine & General Practice, Gibson Building, Radcliffe Infirmary, Oxford OX2 6HE

a3 Clinical Endocrinology Laboratory, Imperial Cancer Research Fund, PO Box 123, Lincoln's Inn Fields, London WC2A 3PX


Total testosterone (T), total oestradiol (E2) and sex hormone-binding globulin (SHBG) concentrations were measured in plasma samples from fifty-one male vegans and fifty-seven omnivores of similar age. Free T concentration was estimated by calculation, in comparison with the omnivores, the vegans had 7% higher total T (P = 0.250), 23% higher SHBG (P = 0.001), 3% lower free T (P = 0.580), and 11% higher E2 (P = 0.194). In a subset of eighteen vegans and twenty-two omnivores for whom 4 d diet records were available, there were statistically significant correlations between T and polyunsaturated fatty acids (r 0.37), SHBG and fat (r 0.43 for total fat, 0.46 for saturated fatty acids and 0.33 for polyunsaturated fatty acids), and SHBG and alcohol (r–0.39). It is concluded that a vegan diet causes a substantial increase in SHBG but has little effect on total or free T or on E2.

(Received September 01 1989)

(Accepted January 19 1990)