Milk drinking and mortality: findings from the Japan collaborative cohort study

J Epidemiol. 2015;25(1):66-73. doi: 10.2188/jea.JE20140081. Epub 2014 Oct 18.


Background: Findings regarding the association between milk consumption and all-cause mortality reported by studies carried out in Western populations have been inconsistent. However, no studies have been conducted in Japan on this issue. The present study aimed to investigate the association of milk drinking with all-cause, cardiovascular, and cancer mortality in Japan.

Methods: The data were obtained from the Japan Collaborative Cohort (JACC) study. A total of 94 980 Japanese adults aged 40-79 years who had no history of cancer, stroke, or chronic cardiovascular diseases were followed between 1988 and 2009. Multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) of mortalities were assessed using a Cox proportional hazard regression model and taking the lowest milk consumption group as the reference.

Results: During a median of 19 years of follow-up, there were 21 775 deaths (28.8% and 35.3% from cardiovascular diseases and cancer, respectively). Drinking milk 1-2 times a month was associated with lower all-cause mortality in men compared to those who never drank milk (multivariable-adjusted HR 0.92; 95% CI, 0.85-0.99). In women, those who drank 3-4 times a week also had a lower mortality risk compared with those who never drank milk (HR 0.91; 95% CI 0.85-0.98). Inverse associations between drinking milk and mortality from cardiovascular diseases and cancer were found only in men.

Conclusions: Drinking milk at least 1-2 times a month was associated with lower all-cause mortality in men compared to never drinking milk. An inverse association was also found between drinking milk and mortality from both cardiovascular diseases and cancer. However, lower all-cause mortality in women was found only in those who drank milk 3-4 times/week.

【背景】: 西洋人を対象に実施された牛乳摂取と総死亡率の関連性に関する研究の結果は一致しておらず、また、日本人においてこの関連は、まだ調べられていない。本研究の目的は、日本人の牛乳飲用と総死亡、循環器疾患死亡、がん死亡との関連性を調べることである。

【方法】: JACC 研究の1988年から2009までの追跡データを用いた。がん、心血管疾患既往がなく、ベースライン時に40-79歳であった94,980人を解析対象者とした。牛乳を全く飲まない群を基準として、多変量調整ハザード比と95%信頼区間を、Cox比例ハザードモデルにより推定した。

【結果】: 中央値で19年の追跡期間中に、計21,775例の死亡が確認された(内、循環器疾患死亡が28.8%、がん死亡が35.3%)。牛乳を全く飲まない男性に比べて、月に1~2回牛乳を飲用する男性の総死亡率は有意に低かった(ハザード比:0.92、95%信頼区間:0.85 – 0.99)。また牛乳を全く飲まない女性に比べて、週に3~4回牛乳を飲用する女性の層死亡率は有意に低かった(ハザード比:0.91、95%信頼区間:0.85 – 0.98)。一方、牛乳飲用と循環器疾患死亡率やがん死亡率との負の関連性は、男性のみにおいて認められた。

【結論】: 牛乳を全く飲まない男性に比べて、月に1~2回以上飲用する男性では、総死亡率が有意に低かった。この関連性は、牛乳飲用と循環器疾患死亡率との負の関連性、牛乳飲用とがん死亡率との負の関連性と一致すると考えられた。一方、女性では、牛乳飲用と総死亡率との負の関連性は週3~4回摂取する群だけで認められた。

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Animals
  • Cardiovascular Diseases / mortality*
  • Cause of Death / trends*
  • Cohort Studies
  • Drinking Behavior*
  • Female
  • Humans
  • Japan / epidemiology
  • Male
  • Middle Aged
  • Milk*
  • Neoplasms / mortality*