Association of Energy and Fat Intake with Prostate Carcinoma Risk.
Association of Energy and Fat Intake with Prostate Carcinoma Risk.
Year: 1999
Authors: Schuurman, A.G. van den Brandt, P.A. Dorant, E. Brants, H.A.M. Goldbohm, R.A.
Publication Name: CANCER
Publication Details: Vol. 86; No. 6; Paages 1019-1027.
Abstract:
The roles of energy and fat intake as risk factors for prostate carcinoma are still questionable. Therefore, these factors were evaluated in the Netherlands Cohort Study described in this article. The cohort study consisted of 58,279 men ages 55�69 years at baseline in 1986. After 6.3 years of follow-up, 642 incident prostate carcinoma cases were available for analysis. Intake of energy, fat, and separate fatty acids were measured by means of a self-administered questionnaire; fat intake was adjusted for energy by regression analysis. The case�cohort method was used to calculate rate ratios (RRs). Analyses were conducted for all prostate carcinoma cases together as well as for case subgroups (latent vs. non-latent and localized vs. advanced). No associations were found in multivariate analyses between prostate carcinoma and intake of energy, total fat, total saturated fatty acids, or total trans unsaturated fatty acids (RR highest vs. lowest quintile: 0.99, 1.10, 1.19, and 0.99, respectively). Oleic acid intake showed a non-significant positive association (RR 5 1.38, 95% CI: 0.88 �2.19). Positive associations were also observed for intake of oleic acid in subgroup analyses. Linoleic (RR 5 0.78, 95% CI: 0.56 �1.09) and alpha- linolenic (RR 5 0.76, 95% CI: 0.66 �1.04) acid intake were associated with non-significantly decreased risks; only for alpha- linolenic acid did these associations persist in subgroup analyses. No associations were found for intake of arachidonic acid, eicosapentaenoic acid, or docosahexaenoic acid. These data suggest that certain fatty acids might be involved in prostate carcinoma occurrence, although the possibility that these were chance findings cannot be ruled out. (Author's abstract)
In some studies, alpha-linolenic acid intake is positively related to prostate carcinoma risk. However, these conclusions are based on not only alpha-linolenic acid intake per se, but also results regarding consumption of meat, milk, and other dairy products. It has been proposed that clinically apparent or advanced prostate tumors might have a different etiology than
latent tumors and thus be effected differently by fatty acid intake. In this investigation, fat intake and prostate carcinoma risk was assessed from the Netherlands Cohort Study (NLCS), which was specifically designed to examine diet in relation to cancer. A positive association with prostate carcinoma risk was found for oleic acid intake, and an inverse association was reported for intake of linoleic acid and alpha-linolenic acid. The trend test for alpha-linolenic acid intake was significant in the age-adjusted analysis. The questionnaire has been validated against a
9-day diet record making it accurate. Besides a validation study, five annually repeated measurements of the food frequency questionnaire were conducted. It is important to note that in the studies that have reported a relationship between increased alpha-linolenic acid and prostate cancer risk, these have been shown mostly for advanced tumors; and in one
study no association was found. Findings from other studies are very diverse, also with respect to nonlatent or advanced prostate tumors. More studies with extensive exposure information
are needed to clarify the role of alpha-linolenic acid in prostate carcinoma etiology. (Editor's comments)
