Tomatoes and lung cancer.

Lung cancer risk: Data about tomatoes in relation with lung cancer risk was provided by a pooled analysis of 7 cohorts and an additional 5 cohorts including a total of 4,191 cases.
A significant protective effect was found in one cohort of small size including 73 cases, but no adjustments were made for possible confounders (28). A nonsignificant protective effect was found in the pooled analysis including 2,994 cases (24). No other associations were found. The average RR = 0.83 (excluding incomplete data from Neuhouser ML [22], Liu Y [25]).
Data about tomato sauce or tomato juice in relation with lung cancer risk was provided by a pooled analysis of 2 cohorts (14). A significant protective effect of tomato sauce was found, but no association was found with tomato juice.

Prospective studies of tomatoes and lung cancer risk:
AuthorCohort nameCasesRelative Risk (RR)
28) Bae JM (2007)The Seoul Male Cancer Cohort Study73RR = 0.42 (0.23-0.76; P = 0.01).
25) Liu Y (2004)The JPHC Study251No association.
24) Smith-Warner SA (2003)Pooled analysis of 7 cohorts2,994RR = 0.83 (0.67-1.03; P = 0.10).
22) Neuhouser ML (2003)The CARET742No association.
7) Fraser GE (1991)The Adventist Health Study55RR = 1.24 (0.51-2.99; P = 0.79).
2) Kvale G (1983)No cohort name defined76RO = 0.87 (P = 0.48).
Total number of cases: 4,191Average RR = 0.83


Lung cancer mortality: Data about lung cancer mortality was provided by one cohort (17). A significant protective effect was found among men, but not women.

Conclusion: A nonsignificant protective effect of tomatoes against lung cancer risk was found in a pooled analysis of 7 studies including 71% of the cases from all cohorts combined, and a significant protective effect was found in another cohort. No (non)significantly increased risks were found in the remaining cohorts. Since the main associations were nonsignificant, evidence was judged suggestive for a protective effect at consumption of ≥ 0.5 tomato/day against lung cancer risk (- 17%).
A significant protective effect of tomato sauce against lung cancer risk was found in a pooled analysis of 2 cohorts of moderate-large size. Tomato sauce possibly protects against lung cancer risk. No level of consumption could be defined for this effect.