Rose E. Frisch

Menstrual cycles: fatness as a determinant of minimum weight for height necessary for their maintenance or onset.

Weight loss causes loss of menstrual function (amenorrhea) and weight gain restores menstrual cycles. A minimal weight for height necessary for the onset of or the restoration of menstrual cycles in cases of primary or secondary amenorrhea due to undernutrition is indicated by an index of fatness of normal girls at menarche and at age 18 years, respectively. Amenorrheic patients of ages 16 years and over resume menstrual cycles after weight gain at a heavier weight for a particular height than is found at menarche. Girls become relatively and absolutely fatter from menarche to age 18 years. The data suggest that a minimum level of stored, easily mobilized energy is necessary for ovulation and menstrual cycles in the human female.

Height and Weight at Menarche and a Hypothesis of Critical Body Weights and Adolescent Events

Height and weight at menarche were found for each subject in three longitudinal growth studies. Early and late maturing girls have menarche at the same mean weight, but late maturers are taller at menarche. Two other major events of adolescence, initiation of the weight growth spurt and maximum rate of weight gain, also occur at an invariant mean weight. The hypothesis is proposed that a critical body weight may trigger each of these adolescent events. Such an interaction would explain the secular trend to an earlier menarche.

Delayed menarche and amenorrhea in ballet dancers

YOUNG female ballet dancers attending professional schools or dancing in companies in which thinness is much admired restrict their food intake and are highly active.1 The unusual eating habits and...

Evidence for a secular trend in age of menarche.

WE present data documenting a secular trend toward an earlier age of menarche in Europe and the United States in the past century. There has been recent controversy on whether such a change has tak...

Height and weight at menarche and a hypothesis of menarche

Height and weight at menarche were estimated by interpolation of longitudinal growth data for 181 girls. Mean weight at menarche, about 48 kg, does not change as menarcheal age increases, whereas mean height increases significantly. Early and late menarcheal girls gain the same amount of height, about 22 cm, and the same amount of weight, about 17 kg, in the interval from the initiation of the adolescent spurt to menarche, though late maturers grow at slower rates during the spurt, including the year of menarche. A hypothesis of a direct relation between a critical weight and menarche is proposed. Such an interaction would explain the delaying effect of malnutrition on menarche and the secular trend to an earlier menarche.

Lower prevalence of breast cancer and cancers of the reproductive system among former college athletes compared to non-athletes.

The prevalence (lifetime occurrence) rate of cancers of the reproductive system (uterus, ovary, cervix and vagina) and breast cancer was determined for 5,398 living alumnae, 2,622 of whom were former college athletes and 2,776 non-athletes, from data on medical and reproductive history, athletic training and diet. The former athletes had a significantly lower risk of cancer of the breast and reproductive system than did the non-athletes. The relative risk (RR), non-athletes/athletes, for cancers of the reproductive system was 2.53. 95% confidence limits (CL) (1.17, 5.47). The RR for breast cancer was 1.86, 95% CL (1.00, 3.47). The analysis controlled for potential confounding factors including age, family history of cancer, age of menarche, number of pregnancies, use of oral contraceptives, use of oestrogen in the menopausal period, smoking, and leanness. Of the college athletes, 82.4% had been on pre-college teams compared to 24.9% of the college non-athletes. We conclude that long term athletic training may lower the risk of breast cancer and cancers of the reproductive system.

BODY FAT, PUBERTY AND FERTILITY

1. The high percentage of fat, about 26–28% in the mature human female, may influence reproductive ability directly through two mechanisms: (a) fat converts androgens to oestrogens; (b) relative fatness influences the direction of metabolism of oestrogen to the most potent or least potent forms. The relative degree of fatness thus is directly related to both the quantity of circulating oestrogen and the biological effectiveness of the oestrogen. This is a neat mechanism for relating rates of growth, nutrition and energy outputs to the energy requirements for reproduction. Fat is the most labile body tissue; it therefore reflects environmental changes more rapidly than other tissues of the body.

Height, weight and age at menarche and the "critical weight" hypothesis.

the observation (1) that both are mutagenic in an Escherichia coli T4 bacteriophage system, make it even more desirable that a persuasive explanation be found for the qualitative difference between them in mutagenicity for Salmonella. ERICH HIRSCHBERG Department of Biochemistry, College of Medicine and Dentistry of New Jersey, Newark 07103 I. BERNARD WEINSTEIN Institute of Cancer Research, Columbia University, New York 10032

Breast cancer among former college athletes compared to non-athletes: a 15-year follow-up.

A growing body of evidence indicates that physical activity is protective against breast cancer. In 1996–97, we conducted a 15-year follow-up of 5398 college alumnae comprised of former college athletes with their non-athletic classmates. Participants completed a detailed mailed questionnaire on their health history from 1981–82 to the present. Excluding women who had died and non-deliverable questionnaires, 84.7% (n = 3940) of the participants in our earlier study responded to the questionnaire; the response rate for former athletes was 86.6% (n = 1945), for non-athletes, 83.0% (n = 1995). Results confirmed our earlier findings. Based on self-reports, former college athletes had a significantly lower risk of breast cancer than the non-athletes. The OR for the 15-year incidence of breast cancer is 0.605 with 95% confidence interval (CI) (0.438–0.835); the 15-year incident breast cancers were 64 among the athletes and 111 among the non-athletes. Among women under 45 the protective effect of physical activity on the risk of breast cancer is considerably greater; odds ratio (OR) = 0.164, 95% CI (0.042–0.636). Athletic activity during the college and pre-college years is protective against breast cancer throughout the life span, and more markedly among women under 45. These results confirm our earlier findings and the findings of other investigators.

Lower Prevalence of Diabetes in Female Former College Athletes Compared With Nonathletes

The prevalence rate of diabetes was determined for 5398 living college alumnae (2622 former college athletes and 2776 nonathletes) from data on medical history, athletic training, and diet. For all ages, the prevalence rate among the former athletes was 0.57% (15/2622) and among the nonathletes was 1.3% (37/2776). The former college athletes and the nonathletes had similar percentages in family history of diabetes, i.e., 12.0 and 13.5%, respectively. For cases occurring at age ≥20 yr (thus assessing the effects of college athletic training), 0.5% (13/2622) of the former college athletes had diabetes compared to 1.2% (32/2776) of the nonathletes; the relative risk is 2.24 [95% confidence limits (CL), 1.19 and 4.74, respectively]. Omitting cases of gestational diabetes, the relative risk of diabetes in nonathletes versus athletes is 3.41 (95% CL, 1.33 and 8.70). The percentages of former athletes and nonathletes that are insulin-using, non-insulin-using, and gestational diabetics did not differ significantly. The athletes were leaner than the nonathletes at all ages up to 70 yr. Of the former college athletes, 82% had been on precollege teams, compared to 25% of the college nonathletes; 74% of the former athletes were exercising regularly, compared to 57% of the nonathletes. We conclude that long-term athletic training is associated with a lower risk of the development Of diabetes.