欧米とアジアの前立腺癌の発生率が異なる理由の一つとして,社会環境因子の一つである食事の差異があげられている.前立腺癌に対する食事,栄養素の影響を調べるため前立腺癌患者と非前立腺癌患者の摂取食事内容,摂取栄養素の違いについて検討した.東京女子医大成人医学センターにおける健康診断男性会員2,500名中,前立腺癌と診断された患者39名と,2年間6ヵ月毎に行った計4回の健康診断で,PSAが常に4.0ng/ml以下の会員416名を対照(非前立腺癌患者)とし比較検討した.健康診断前3日間の食事質問票を用いて,前立腺癌患者は確定診断前の摂取内容を,対照は最新の摂取内容を食事分析ソフトで解析した.前立腺癌患者の食事では,肉類が有意に多く摂取されており,栄養素としてビタミンAの摂取が多く,ビタミンDの摂取が少なかった.肉類摂取と前立腺癌の発生の関連が疑われた.ビタミンAは動物性食品に多く含まれており,前立腺癌患者は肉類の摂取が多いため有意差がでた可能性が考えられた.ビタミンDは魚介類に多く含まれ,非前立腺癌患者での癌細胞の増殖抑制効果との関連が推察された.肉食を少なくし,ビタミンDが多く含まれる魚介類の摂取を勧めることにより,前立腺癌の発生を抑制する可能性が考えられた.One of the reasons for the differing incidence of prostate cancer between Asian and Western countries is diet, which is a socioenvironmental factor. In order to ascertain the effects of food and nutrient intake on prostate cancer, the present study investigated 2,500 men who underwent health screening at our Institute. Subjects were patients who were diagnosed with prostate cancer (n=39) and those without prostate cancer (patients in whom Prostate specific antigen (PSA) was consistently below 4.0 ng/ml over a two-year period, n=416). Questionnaires were used to ascertain food intake for three days before each health screening, and diet analysis software was used to compare food intake. For the prostate cancer patients, meat intake was significantly higher, and in terms of nutrients, vitamin A intake was higher, while vitamin D intake was lower. Vitamin A is abundant in animal meat and vitamin D is plentiful in seafood, thus suggesting a correlation between seafood intake and cancer cell suppression for the men without prostate cancer. The results suggest that it may be possible to lower the incidence of prostate cancer by recommending people to eat less meat and consume more seafood rich in vitamin D
