LONG-TERM EFFECTS OF PARTICIPATION IN A RANDOMIZED TRIAL OF A LOW-FAT, HIGH-CARBOHYDRATE DIET

In 1982 we started a series of pilot studies to examine the feasibilit y of dietary intervention with a low-fat, high-carbohydrate diet in wo men with extensive mammographic densities, The purpose of the present paper is to examine the long-term effects of participation in these st udies by assessing nutrient intake and other variables several years a fter active participation had stopped, Two hundred sixteen women were eligible for the follow-up study and were invited to attend an intervi ew with a dietitian, Data were collected by food frequency questionnai re from 157 subjects (73%), and blood was obtained from 115 subjects, Total energy intake was slightly lower in the intervention group, Tota l fat and percent energy from fat were significantly lower in the inte rvention group, The intake of all types of fat (saturated fat, linolei c acid, and oleic acid) and dietary cholesterol was lower in the inter vention group; however, the polyunsaturated/saturated fat ratio did no t differ between the groups, Total cholesterol and apoprotein B levels were lower in the intervention group compared to the control group, F ollicle-stimulating hormone was 29% higher in postmenopausal members o f the intervention group than in controls, but there was no difference in levels of estradiol, A total of 19 women enrolled in pilot studies had developed breast cancer, 5.7 times the number expected, confirmin g that the selection of women with extensive mammographic densities do es identify a high-risk group, These data suggest that even quite shor t periods of intensive dietary counselling may have prolonged effects on diet, and that once subjects have adopted new dietary habits, the h abits may persist even in the absence of continued counselling.