Dietary Patterns Affect Lung Cancer Risk in Never Smokers

Abstract

A number of studies suggest a role of dietary factors as risk predictors of lung cancer in never smokers. However, it is difficult to interpret the observed associations of lung cancer risk with any particular dietary item due to high correlation among different dietary items. In this study, we derived uncorrelated patterns of dietary items in the never smokers and evaluated the association of these patterns with lung cancer risk, using food frequency data from 299 never-smoker lung cancer patients and 317 controls enrolled in an ongoing case-control lung cancer study. We identified 2 major dietary patterns in never smokers: a "healthy eating" pattern including vegetables, fruits, and low-fat food items, and a "mixed dishes" pattern including most foods with positive loadings. Using multivariable regression analysis, we show that the healthy eating pattern is associated with a significant reduction of lung cancer risk among never smokers. The effect of the healthy eating pattern remained significant after adjustment for age, gender, education, caloric intake, secondhand smoke exposure, and family history of cancer. This finding, if confirmed in a prospective study, has a clear preventive significance, by promoting interventions encouraging healthier diets.

Different dietary patterns and reduction of lung cancer risk: A large case-control study in the U.S.

“…This observation was consistent with the findings from previous dietary pattern studies on lung cancer that the beneficial effects of dietary patterns characterized by high consumption of fruits or vegetables were only evident in current or former smokers456910. Smoking causes lung cancer in part through its pro-oxidant properties31.…”

“…However, most of the studies were conducted outside of the U.S 5678,. except one small study4. Also, evidence on other American dietary patterns is very limited.…”

Index-based dietary patterns and risk of lung cancer in the NIH–AARP diet and health study

“…12 All other studies of dietary patterns and lung cancer risk used data-driven methods. When principal components analysis was used to identify a 'prudent' or healthy diet pattern (characterized by high intake of fruits, vegetables, lean meats, whole grains and antioxidants), a reduced risk of lung cancer was observed for heavy smokers in an Italian cohort, 13 men in the Netherlands Cohort Study, 18 a US case-control study of never smokers 14 and several case-control analyses from Uruguay. 15,17 A 'high-meat' or 'Western' dietary pattern characterized by high intake of red and processed meat was associated with increased lung cancer risk in case-control studies from Uruguay 15-17 and a Netherlands cohort, 18 but was not associated with lung cancer risk in an Italian cohort.…”

“…10 Examining dietary patterns considers that individual dietary components can be highly correlated or have synergistic or antagonistic biologic interactions that produce associations with disease risk that cannot be captured by studying a single food or nutrient. 11 In previous studies of dietary patterns and lung cancer risk, [12][13][14][15][16][17][18][19] all but one study 12 used data-driven approaches, such as factor analysis, which create dietary groupings that are unique to each study and do not allow for comparison across studies. An alternative approach is to use indices to define patterns a priori, based on dietary guidelines or recommendations, which can be used to compare diet quality across study populations.…”

CIMMYT Series on Carbohydrates, Wheat, Grains, and Health: Carbohydrates, Grains, and Whole Grains and Disease Prevention. Part IV. Cancer Risk: Lung, Prostate, and Stomach

“…For lung cancer risk, it may also be important to assess the interaction of diet with smoking patterns. In fact, one study showed that a "healthy eating" pattern that included vegetables, fruits, and low-fat foods was associated with a significant reduction in lung cancer risk among those who never smoked (33). Assessment of diet quality in the NIH-AARP Diet and Health study (N = 460,770) by scoring compliance with any of four common indices (Healthy Eating Index-2010, Alternative Healthy Eating Index-2010, alternative Mediterranean Diet score, and DASH Diet) yielded very similar results (34).…”