Now the company plans to cut the trans-fatty acids in its fries by 48% and saturated fat by 16%.

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Fast food often contains high levels of saturated- and trans-fatty acids, which are known to affect immunity, while fruit is rich in antioxidants and other beneficial compounds, say the researchers.

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But this research linked other oils -- like those found in margarine, fried and baked goods and salty snacks that contain so-called trans-fatty acids -- to a higher incidence of breast cancer.

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In contrast, many studies suggest that diets which are rich in trans- and saturated fatty acids, such as those containing a lot of deep-fried foods and butter, have bad effects on cognition.

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Soon it may order a disclosure as well about so-called trans unsaturated fatty acids, made from partially hydrogenated oils used to prepare a lot of junk food and said to be even worse culprits in artery-clogging.

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