Brief exposure to high levels of PCBs and dioxins may cause skin lesions and affect the liver (the tolerated daily intake for dioxin is about 1 picogram - one trillionth of a gram - per kg body weight).

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In 1960, chicken and pork accounted for around 4% of daily caloric intake.

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Dr. Rosen served on an Institute of Medicine panel that in 2010 recommended a daily vitamin D intake of at least 600 IUs for children and adults up to age 70.

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The daily recommended intake of vitamin E is about 22 international units for those 14 and older, and is relatively easy to obtain from oils such as sunflower, almonds, peanut butter, and spinach.

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