The current tolerable upper limit of vitamin D intake is 50 mcg (2, 000 IU) per day.

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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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Because these studies are mainly observational, extensive research is under way to determine the causal relationship between vitamin D levels and disease as well as the role of increasing vitamin D intake.

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In the UK "between October and May virtually no-one makes vitamin D because of the sunlight" regardless of your skin colour, so Vitamin D levels are dependent on dietary intake, he said.

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In fact, I'd rather hear all about your fluid intake far more than how many fake points Tom Brady scored in your Week 3 win over the A-Town Booger Heads.

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The Institute of Medicine, a group that uses scientific research to formulate public health policies, currently recommends an Adequate Intake, or AI, rather than a specific daily amount of vitamin D.

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