Dietary Fat, Eicosanoids and Breast Cancer Risk
Condition: Breast Cancer
MeSH terms: Breast Neoplasms
Study type: Interventional

Summary: 
      The primary objective of this investigation is to determine whether diets designed to
      increase plasma n3 concentrations (a low fat diet, with or without n3 fatty acid enrichment),
      will favorably affect sex hormone distribution in women in a direction associated with
      reduced risk of sex hormone-mediated cancer development. Specifically, we hypothesize that an
      increased concentration of circulating n3 fatty acids will reduce the biochemical markers
      associated with increased risk for developing certain sex hormone mediated cancers such as
      breast cancer
    

Detailed description: 
      The guiding concept of our proposal is that both the total fat and the fatty acid composition
      of the diet contribute to a milieu associated with the risk for sex-hormone mediated cancers.
      Specifically, we hypothesize that an increased concentration of circulating n3 fatty acids
      will reduce the biochemical markers associated with increased risk for developing certain sex
      hormone mediated cancers such as breast cancer. When compared with the high fat diet, we
      expect n3 concentrations to increase and sex hormone levels to decrease after both low fat
      and low fat/n3 rich diets, with the greatest response in the low fat-n3 supplemented group.
      The aims of this project are: 1) to evaluate the effects of total fat and n3 fatty acid
      consumption on plasma and urine sex hormone concentrations in postmenopausal women, 2) to
      evaluate the relationship between plasma concentrations of fatty acids and plasma and urinary
      sex hormone concentrations, and 3) to evaluate the effects of total fat and n3 fatty acid
      consumption on the associations between sex hormone concentrations and urinary prostaglandin
      E2 and thromboxane B2 concentrations.

      The primary objective of this investigation is to determine whether diets designed to
      increase plasma n3 concentrations (a low fat diet, with or without n3 fatty acid enrichment),
      will favorably affect sex hormone distribution in women in a direction associated with
      reduced risk of sex hormone-mediated cancer development. The primary endpoints to be
      evaluated include plasma and urinary sex hormone concentrations as follows:

      Endpoints associates with increased risk factors for breast cancer risk: plasma estradiol
      (E2), estrone (E1), estrone sulfate (E1 sulfate), testosterone, androstenedione, sex hormone
      binding globulin (SHBG), dehydroepiandrosterone (DHEA), dehydroepiandrosterone sulfate
      (DHEAS), Measures of estrogen action: plasma follicle stimulating hormone (FSH), urinary
      estrogen metabolites.

      Measures of systemic arachidonic acid-derived eicosanoids: urinary bicyclo-prostaglandin E2
      (PGEa), 2,3-dinor thromboxane B2 (TXB2).

      Measures reflecting influence of dietary fat and fatty acid intake: plasma phospholipid,
      cholesterol ester, triglyceride and free fatty acid composition.
    

Intervention name(s): Low Fat diet; Low Fat high n3 diet; High Fat Diet
Intervention type(s): Other; Other; Other
Intervention description(s): Low fat diet = 20% fat; Low Fat high n3 diet = 20% fat + 3% n3; High Fat Diet = 40% fat
Allocation: Randomized
Intervention model: Crossover Assignment
Masking: None (Open Label)
Primary purpose: Prevention
Keywords: omega-3 fatty acids; sex hormones; urinary sex hormone metabolites