Volume 4 Supplement 1
Association of self-reported consumption of cooked meat, fish, seafood and eggs with prostate cancer risk among Nigerians
© Ukoli et al; licensee BioMed Central Ltd. 2009
Published: 10 February 2009
The observation that the prevalence of latent PCa at autopsy is similar for African-American and African populations , and that Asian populations record latent PCa rates comparable to those of U.S. whites , despite large geographical differences in PCa incidence world wide, supports the suggestion that environmental cancer 'promoting' factors play a more important role than cancer 'initiating' factors in the etiology of clinically significant PCa [3, 4]. Epidemiological studies have demonstrated that dietary animal fat and high energy intake are associated with increased PCa risk, while dietary marine fat is negatively associated with this risk . Higher meat intake is consistently reported to be associated with increased PCa, possibly due to heterocyclic amines such as 2-amino-1-methyl-6-phenylimidazo [4,5-b]pyridine [PhIP], polycyclic aromatic hydrocarbons such as benzo [a]pyrene [BaP], and alpha-methylacyl-CoA racemase, produced in the process of grilling or frying red meat . High consumption of cooked processed meats has also been reported to contribute to the high burden of PCa risk among African-Americans . In China, a low-incidence region for PCa, the consumption of salted fish and preserved meats has been reported to be associated with a significant increase in PCa risk . Current evidence from cohort studies supporting the association between high fish intake with reduced PCa risk is however less convincing for countries with low or high fish consumption [9, 10]. Meat, fish, cheese and egg intake were not associated with PCa risk in a Netherland cohort study . Like other Sub-Saharan designated low-incidence regions for PCa, Nigeria has reported an moderate upward incidence trend, with PCa becoming the most diagnosed male cancer [12, 13]. This trend is postulated to result from improved diagnosis, increased longevity, and the progressive replacement of their traditional low-fat diet with a more westernized diet high in meat and processed foods. This study examined the association of self-reported consumption of cooked meat, fish, sea food, and eggs with PCa risk among Nigerians in a case-control design.
Computing annual intake of food items by multiplying average self-reported annual frequency of food intake by unit portion size
Annual Intake Pattern
365 × 2
Mid-Interval Frequency × Unit Portion Size
Transform to Quartiles
Demographic and other characteristics of prostate cancer cases and controls in the Nigerian study population
n = 56
n = 268
Annual Income (Naira)§
History of BPH
BMI ≥ 30 (kg/m2)
BMI ≥ 35 (kg/m2)
0.97 ± 0.09
0.92 ± 0.07
23.9 ± 5.15
23.4 ± 3.84
165.1 ± 9.37
166.8 ± 7.60
Skin fold thickness‡(mm)
8.9 ± 4.19
8.9 ± 4.09
Rate of frequent‡ intake of meat, fish and eggs among prostate cancer cases and controls in the Nigerian study population
All white meat
All red meat
Fish & sea food
Odds ratios and 95% confidence interval (CI) for prostate cancer risk comparing lowest to highest quartiles of dietary intake of meat, fish, seafood and eggs in the Nigerian study population
Annual Intake Quartiles
p for trend
All sea food
Red meat is one of the main content of western diet proposed as a modifiable risk factor for PCa . The increase in PCa incidence in Japan in the 1980s , and sub-Saharan Africa more recently, has been attributed to transition from the traditional low-animal fat diet to a 'westernized' diet high in animal fat, leading to modification of the natural history of PCa [12, 13, 15, 16]. Unlike other studies that reported strong associations with red meat  and organ meat intake , our study demonstrated only a modest increased risk trend across quartiles of red and organ meat intake, but the OR for risk was not statistically significant. The fact that meat is usually boiled in this population may explain the attenuated effect of red meat since carcinogens are produced by grilling and frying [6, 18]. Our findings are consistent with other reports that did not demonstrate PCa risk association with total meat, white meat , and egg intake .
Fish is the main source of protein for shoreline Africans such as Nigerians [21, 22], and is more popular than meat in this population. The three commonly eaten fish are the saltwater croaker and mackerel, and the fresh water catfish, usually dried, broiled, and sometimes fried. Our data did not support the negative association between fish intake and PCa risk as reported in the study of Native Alaskan Eskimos who eat large quantities of fish . Similarly a cohort study in Japan did not find PCa risk association with fish intake among men 40–69 years . Japanese traditional diet, high in soybean and fish, is associated with low PCa risk , underscoring the importance of an entire dietary style over individual food items.
Recall error associated with the FFQ may be limited in this study given the homogeneous nature of Nigerian diet, and exposure misclassification was reduced by the use of life-size food portion models. We did not transform portion size units to actual weight, and this might attenuate statistical association if between-person differences in portion size contribute to between-person variability in amount consumed. We also did not collect information about the type of fish eaten, which together with method of preparation might be very important in cancer etiology. Despite these limitations we have no reason to disagree with the hypothesis postulated by other authors that high intake of red meat contributes to PCa risk. We however had no evidence to support the hypothesis that high intake of fish reduces PCa risk. In the absence of nutrient composition tables of Nigerian foods, we have reported preliminary results of PCa risk associations of selected food items acknowledging the limitations of FFQ in cancer risk assessment.
This study examined the association of self-reported consumption of cooked meat, fish, sea food, and eggs with PCa risk among Nigerians. Fish is more popular in the Nigerian population, followed by red meat, while chicken and eggs are not popular food items. The overall serving portions reported by participants are very modest. Our data did not demonstrate statistical association between frequent consumption of fish, seafood, and eggs, red, white and organ meat with PCa risk. However, consistent with previous reports, there was a modest significant increased risk trend for men in the upper quartile of quantity of red meat consumed. In contrast to other reports we did not observe any risk reduction with the quantity of fish consumed. These preliminary findings need to be confirmed in a large study sample, and future research should investigate the impact of westernized dietary transition on the development of PCa in a designated low-incidence region such as Nigeria.
We thank the community participants, patients, and personnel of the University of Benin Teaching Hospital, Specialist Hospitals Benin & Warri, Eku Baptist Hospital, Udo and Warri Health Centers, the study interviewers, and Mr. Luke Ani, the study coordinator. Supported by the Department of Defense (DOD) grants DAMD17-02-1-0068 & W81XWH-05-1-0229.
This article has been published as part of Infectious Agents and Cancer. Volume 4 Supplement 1, 2009: Second Annual International African-Caribbean Cancer Consortium Conference. The full contents of the supplement are available online at http://www.infectagentscancer.com/supplements/4/S1.
- Jackson MA, Kovi J, Heshmat MY, Ogunmuyiwa TA, Jones GW, Williams AO, Christian EC, Nkposong EO, Rao MS, Jackson AG, Ahluwalia BS: Characterization of prostatic carcinoma among blacks: a comparison between a low-incidence area, Ibadan, Nigeria, and a high-incidence area, Washington, DC. Prostate. 1980, 1 (2): 185-205. 10.1002/pros.2990010205.View ArticlePubMed
- Ryuichi Yatani, Taizo Shiraishi, Kazuya Nakakuki, Itsuo Kusano, Hideki Takanari, Takuji Hayashi, Stemmermann Grant: Trends in frequency of latent prostate carcinoma in Japan from 1965–1979 to 1982–1986. J Natl Cancer Inst. 1988, 80: 683-7. 10.1093/jnci/80.9.683.View Article
- Delongchamps NB, Singh A, Haas GP: Epidemiology of prostate cancer in Africa: another step in the understanding of the disease?. Curr Probl Cancer. 2007, 31 (3): 226-36. 10.1016/j.currproblcancer.2007.01.004.View ArticlePubMed
- Dhom G: Epidemiological aspects of latent and clinically manifest carcinoma of the prostate. J Cancer Res Clin Oncol. 1983, 106 (3): 210-8. 10.1007/BF00402610.View ArticlePubMed
- Astorg P: Dietary fatty acids and colorectal and prostate cancers: epidemiological studies. Bull Cancer. 2005, 92 (7): 670-84.PubMed
- Cross AJ, Peters U, Kirsh VA, Andriole GL, Reding D, Hayes RB, Sinha R: A prospective study of meat and meat mutagens and prostate cancer risk. Cancer Res. 2005, 65 (24): 11779-84. 10.1158/0008-5472.CAN-05-2191.View ArticlePubMed
- Rodriguez C, McCullough ML, Mondul AM, Jacobs EJ, Chao A, Patel AV, Thun MJ, Calle EE: Meat consumption among Black and White men and risk of prostate cancer in the Cancer Prevention Study II Nutrition Cohort. Cancer Epidemiol Biomarkers Prev. 2006, 15 (2): 211-6. 10.1158/1055-9965.EPI-05-0614.View ArticlePubMed
- Jian L, Zhang DH, Lee AH, Binns CW: Do preserved foods increase prostate cancer risk?. Br J Cancer. 2004, 90 (9): 1792-5. 10.1038/sj.bjc.6601755.PubMed CentralView ArticlePubMed
- Stacewicz-Sapuntzakis M, Borthakur G, Burns JL, Bowen PE: Correlations of dietary patterns with prostate health. Mol Nutr Food Res. 2008, 52 (1): 114-130. 10.1002/mnfr.200890018.View ArticlePubMed
- Chan JM, Gann PH, Giovannucci EL: Role of diet in prostate cancer development and progression. J Clin Oncol. 2005, 23 (32): 8152-60. 10.1200/JCO.2005.03.1492.View ArticlePubMed
- Schuurman AG, Brandt van den PA, Dorant E, Goldbohm RA: Animal products, calcium and protein and prostate cancer risk in The Netherlands Cohort Study. Br J Cancer. 1999, 80 (7): 1107-13. 10.1038/sj.bjc.6690472.PubMed CentralView ArticlePubMed
- Osegbe DN: Prostate cancer in Nigerians: facts and nonfacts. J Urol. 1997, 157 (4): 1340-3. 10.1016/S0022-5347(01)64966-8.View ArticlePubMed
- Ogunbiyi JO, Shittu OB: Increased incidence of prostate cancer in Nigerians. J Natl Med Assoc. 1999, 91 (3): 159-64.PubMed CentralPubMed
- Kolonel LN: Fat, meat, and prostate cancer. Epidemiol Rev. 2001, 23: 72-81.View ArticlePubMed
- Parkin DM, Whelan SL, Ferlay J, Raymond L, Young J: Cancer incidence in five continents, IARC scientific publications No. 143. 1997, Lyon, France, International Agency for Research on Cancer, VII:
- Drewnowski A, Popkin BM: The nutrition transition: new trends in the global diet. Nutr Rev. 1997, 55 (2): 31-43.View ArticlePubMed
- Walker M, Aronson KJ, King W, Wilson JW, Fan W, Heaton JP, MacNeily A, Nickel JC, Morales A: Dietary patterns and risk of prostate cancer in Ontario, Canada. Int J Cancer. 2005, 116 (4): 592-8. 10.1002/ijc.21112.View ArticlePubMed
- Sinha R, Rothman N: Exposure assessment of heterocyclic amines (HCAs) in epidemiologic studies. Mutat Res. 1997, 376: 195-202.View ArticlePubMed
- Cross AJ, Peters U, Kirsh VA, Andriole GL, Reding D, Hayes RB, Sinha R: A prospective study of meat and meat mutagens and prostate cancer risk. Cancer Res. 65 (24): 11779-84. 10.1158/0008-5472.CAN-05-2191.
- Schuurman AG, Bradt vanden PA, Dorant E, Goldbohm RA: Animal products, calcium and protein and prostate cancer risk in The Netherlands Cohort Study. Br J Cancer. 1999, 80 (7): 1107-13. 10.1038/sj.bjc.6690472.PubMed CentralView ArticlePubMed
- Robson A, : Shellfish view of Omega-3 and sustainable fisheries. Nature. 2006, 444: 1002-10.1038/4441002d.View Article
- Abidoye RO, Madueke LA, Abidoye GO: The relationship between dietary habits and body-mass index using the Federal Airport Authority of Nigeria as the sample. Nutr Health. 2002, 16 (3): 215-27.View ArticlePubMed
- Parkinson AJ, Cruz Al, Heyward WL, Buklow LR, Hall D, Barstaed L, Connor WE: Elevated concentrations of plasma polyunsaturated fatty acids among Alaskan Eskimos. Am J Clin Nutr. 1994, 59: 384-388.PubMed
- Sato F, Shimazu T, Kuriyama S, Ohmori K, Nakaya N, Tsuji I, Arai Y: Fish intake and the risk of prostate cancer in Japan: a prospective cohort study. Nippon Hinyokika Gakkai Zasshi. 2008, 99 (1): 14-21.PubMed
- Sonoda T, Nagata Y, Mori M, Miyanaga N, Takashima N, Okumura K, Goto K, Naito S, Fujimoto K, Hirao Y, Takahashi A, Tsukamoto T, Akaza H: A case-control study of diet and prostate cancer in Japan: possible protective effect of traditional Japanese diet. Cancer Sci. 2004, 95 (3): 238-42. 10.1111/j.1349-7006.2004.tb02209.x.View ArticlePubMed
This article is published under license to BioMed Central Ltd. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.