Dietary vitamin A/precursors and lung cancer risk in Taiwan: with special reference to garland chrysanthemum and sweet potato leaves consumption
| Autor: | Yi-Ru Jin, 金一如 |
|---|---|
| Rok vydání: | 2005 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 93 In 2004, lung cancer has been the leading cause of cancer death in Taiwan. Many studies demonstrate that vitamin A plays a crucial role in the prevention of lung cancer. However, few epidemiologic studies have examined the association of dietary vitamin A/precursors and lung cancer in Taiwan. Therefore, a case-control study was conducted to investigate the relationship between the consumption of local common foods that are rich in vitamin A/precursors and the risk of lung cancer. The cases were 301 newly diagnosed patients with histopathologically confirmed primary lung cancer. Two control groups were recruited: 602 hospital controls and 602 neighborhood controls. The consumption of 13 food items and vitamin supplements was estimated with the use of a structured food-frequency questionnaire in face-to-face interviews. Adjusted odds ratios (AOR) and the corresponding 95% confidence intervals (CI) were evaluated with controlling for potential confounders, using the conditional logistic regression model. It was found that reduced risk for lung cancer was associated with increased intakes of vitamin A, a-carotene, or b-carotene from various food groups except fruits. However, inverse associations were not observed for vitamin A, a-carotene, or b-carotene intake from various food items, except garland chrysanthemum and sweet potato leaves. On the other hand, retinol intake from food groups or items was not correlated with lung cancer development. Additionally, more servings of vegetables (AOR for the highest versus the lowest quartile = 0.67-0.70, 95% CI = 0.42-1.08, plinear trend = 0.04), garland chrysanthemum (AOR for the highest versus the lowest tertile = 0.58-0.74, 95% CI = 0.37-1.14, plinear trend = 0.01-0.04) and sweet potato leaves (AOR for the highest versus the lowest tertile = 0.43-0.65, 95% CI = 0.28-0.96, plinear trend £ 0.03) were associated with the reduced risk for lung cancer. In conclusion, there were protective effects of dietary intake of vitamin A, a-carotene and b-carotene. The vegetables provided higher potential protection against development of lung cancer than the fruits, especially for garland chrysanthemum and sweet potato leaves. Therefore, our findings suggest that more consumption of garland chrysanthemum and sweet potato leaves might reduce the risk of lung cancer in Taiwan. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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