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Chemistry LibreTexts

Why Fats Don't Add Up on Food Nutrition Labels

  • Page ID
    143537
  • Equations and Mass Relationships in Everyday Life

    If you're observant and pay attention to nutrition labels on foods, you may have noticed labels like the one here, where the fats don't seem to add up.

    If one 12 g serving of Crisco® contains 3 g of saturated fat, 0g of trans fat, 6 g of polyunsaturated fat, and 2.5 g of monounsaturated fat[1] what happened to the missing 0.5 g of fat? 3 g + 0 g + 6 g + 2.5 g = 11.5 g!

    In many cases there's a bigger disparity than this. The fats don't add up[2] because the weight of glycerol is not included in the separately listed components. Trans fatty acids are now recognized as a major dietary risk factor for cardiovascular diseases, and the US FDA has revised food labeling requirements to include trans fats.[3]

    Are companies pulling the wool over our eyes? In order to understand what's going on, we need to look into the nature of vegetable fats and oils, which are triglycerides.