A randomized trial of a low‐fat dietary intervention in women at high risk for breast cancer

Abstract

A randomized intervention trial of dietary fat reduction to 15% of total calories was initiated in 1987 for women at high risk for breast cancer to determine the feasibility of recruiting and maintaining them on a low-fat diet. The study has enrolled 194 women between the ages of 18 and 67 years who met at least one of three eligibility criteria: 1) a first-degree relative with breast cancer, 2) a P2 or DY Wolfe mammographic pattern, and 3) a prior breast biopsy demonstrating epithelial hyperplasia with or without atypia. Eligible women must also have had diets that contained > or = 30% of calories from fat at entry. Women were randomized to a nonintervention usual diet vs. a 15% low-fat diet. Recruitment was sought through physicians, personal mailings, breast cancer patients, and the news media. Two study sites participated: a large urban hospital affiliated with a university medical center and a community oncology private practice. The results from both institutions were similar and demonstrated that a low-fat dietary plan could be effectively conducted in private as well as academic settings with recruitment tailored to the community where the trial is being conducted. Reduction in dietary fat intake was maximal during the first three months of the dietary intervention and remained stable throughout 12 months of follow-up. Reductions in total calories, weight loss, and percent body fat were minimal. The nonintervention group experienced no major change in their diet. We conclude that it is feasible to recruit women who are at high risk for breast cancer into a dietary intervention trial and with sufficient dietary counseling and motivation on the part of participants, reduction in dietary fat intake can be achieved and maintained. More in-depth analyses of these data will be presented in subsequent reports.

The role of dietary fat in body fatness: evidence from a preliminary meta-analysis of ad libitum low-fat dietary intervention studies

“…If results from the same study were reported in more than one publication, the data were included only once (n = 15). A total of 15 publications reporting 16 studies met the inclusion criteria (Lee-Han et al 1988;Boyd et al 1990;Buzzard et al 1990;Ornish et al 1990;Bloemberg et al 1991;Sheppard et al 1991;Baer, 1993;Hunninghake et al 1993;Kasim et al 1993;Raben et al 1995;Pritchard et al 1996;Siggaard et al 1996;Simon et al 1997;Stefanick et al 1998;Weststrate et al 1998). These studies included a total of 1728 individuals, 1074 women and 654 men.…”

“…We then excluded studies if the intervention period was less than Baer (1993) Non-randomized Blood lipids 12 months I 0/33 Hunninghake et al (1993) Randomized Blood lipids 9 weeks I 40/65 Kasim et al (1993) Randomized Blood lipids 12 months Raben et al (1995) Non-randomized Blood lipids 11 weeks I 6/18 Pritchard et al (1996) Randomized Body composition 12 weeks I 0/18 Siggaard et al (1996) Non-randomized Body composition 12 weeks Simon et al (1997) Randomized Breast cancer prevention 12 months Weststrate et al (1998) Randomized Body weight blood lipids 6 months I 58/59…”

Effect of Low-Fat and/or Low-Energy Diets on Anthropometric Measures in Participants of the Women’s Diet Study

“…A recent review of 16 studies utilizing low-fat interventions of at least two months duration in non-obese individuals showed a mean decrease in body weight of 2.55 kg [5]. At our own institution using the same low-fat intervention strategy used in the present work (goal of 15% of energy from fat), there was a weight loss of 3.4 kg over 12 months [9]. The present study had the advantage, however, of being able to compare the effects of counseling for reducing fat intake (to 15% of calories), reducing energy intake (by 25%) or reducing both fat and energy intake on anthropometric measures in women over 12 weeks [10].…”

Epidemics of Obesity and Metabolic Disorders: Are Dietary Fats or Sugars Involved?

“…These studies show that apart from energy restriction, a low-fat diet alone is effective in inducing weight loss in overweight subjects, with an observed mean weight loss of about 1.8 kg/month for the first 6 months. Although the rate of weight loss on an ad libitum, low-fat, high-carbohydrate diet may not be as rapid as that induced by energy restriction (calorie counting), the diet has been found to provide greater satiety and subsequently, the compensation for the decrease in energy intake is not complete, i.e., energy intake remains decreased [71,54,65,66]. Even in studies where the goal is to maintain a constant energy intake, the total energy intake is often unintentionally reduced when a low-fat diet is consumed [58].…”