Vegetables and coronary heart disease (CHD).

13 articles, providing information about 12 different cohorts were found.

Heart disease risk: Data about heart disease risk was provided by 7 cohorts, including a total of 3,896 + X cases (no amount of cases was available from one cohort of very small size [3]).
Significant protective effects were found in 3 cohorts (10, 13) including 3,312 cases. One of the cohorts included current smokers only (13), and pooled results from the other 2 cohorts (10), shows the association was significant among current smokers only. No associations were found in the remaining 4 cohorts (3, 18, 20, 29).

Note: In 2007, He FJ. published a meta-analysis of 9 cohort studies relating vegetables to CHD risk. This analysis excluded data from "The Shibata Study" (Tanaka H. 1987), and "The Study Of Men Born In 1913" (Strandhagen E. 2000), but it included data from 4 other cohorts which are not added to the following table. Excluded articles & motivations for exclusion are as follows:

  • Fraser GE (1992). The Adventist Health Study provided information about salads and legumes, but not total vegetables. Information about these variables is added to the related items in the menu.
  • Knekt P (1996). Provided information about CHD death instead of risk. Therefore, information about this variable was added to the table of vegetables in relation to CHD mortality.
  • Mann JI (1997). Provided information about green vegetables, but not total vegetables. Therefore, information about this variable is added to the related item in the menu.
  • Liu S (2001). Provided information about vegetables rich in carotenoids, but not total vegetables. Therefore, information about this variable is added to the related item in the menu.

Effect modification: Data about effect modification by multivitamin use was provided by a pooled analysis of 2 cohort studies (10). A protective effect of vegetables was confined to non-users of multivitamin supplements.

Heart disease mortality: Data about heart disease mortality was provided by 7 cohorts, including a total of 2,094 cases.
Significant protective effects were found in 3 cohorts (11, 13, 30) including 987 cases, and a nonsignificant protective effect was found in a fourth cohort (2), including 110 cases. Three out of four of these cohorts consisted of men only. No associations were found in 3 other cohorts (7, 18, 31).

Conclusion: Significant protective effects against CHD risk were found in 3 cohorts of moderate-large size, including 85% of all cases. Effects were confined to non-users of multivitamins and current smokers. Total vegetables possibly protect against CHD risk. This effect is possibly confined to non-users of multivitamin supplements and to current smokers. No level of consumption could be defined for this effect.
Significant protective effects against CHD death were found in 3 cohorts, two of which were of very small size (including 47% of all cases). Most cohorts consisted of men only. No (non)significantly increased risks were found. Suggestive evidence was found for a protective effect of vegetables against CHD death among men. No level of consumption could be defined for this effect.