Cheek cell fatty acids as indicators of dietary lipids in humans.

Analysis of cheek cell lipids has been suggested as a noninvasive method for monitoring the fatty acid composition of diets in humans. In a pilot study conducted to determine the validity of the method, cheek cell samples were collected from subjects consuming a low fat (20% of calories) diet consisting of fatty acids with either a 1.0 or 0.3 P/S ratio. Neither total lipid nor polar lipid fatty acids in cheek cells consistently reflected the P/S ratio of the diets. However, there were trends, particularly in the nonpolar lipids, suggesting that cheek cell fatty acid ratios might be useful for monitoring the fatty acid composition of the diets. The diet with the higher P/S ratio (1.0 vs 0.3) consistently resulted in cheek cell lipids with lower ratios of 18:1/saturated fatty acids and greater 18:2/20:4, 18:2/18:1 and 18:2/18:0 fatty acid ratios.