It has been found that eating uncooked vegetables without fat inhibits the absorption of carotenoids, the cancer-fighting antioxidants in fruits and vegetables which constitute the red, yellow and orange pigments.

Because carotenoids are fat soluble they cannot be absorbed without fats being present. A study found that when eating salads without fat, virtually no absorption of alpha-carotene, beta-carotene or lycopene takes place. But when salads were eaten with reduced-fat or regular dressing, carotenoid levels went up substantially.

As well as dressing, eating small amounts of avocado or cheese with uncooked vegetables may help carotenoid absorption.