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ARS Home Office of Communications Images Photos Apr10





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Image Number K9834-1 After determining the role of vitamin A in maintaining sight, researchers determine adults should consume a minimum of 5,000 to 6,000 international units of vitamin A per day. Later, in the 1970s, scientists at the Beltsville Human Nutrition Research Center discover that supplementing vitamin A with zinc helps prevent blindness. ARS has five other human nutrition centers in Boston, Massachusetts; Houston, Texas; Grand Forks, North Dakota; Davis, California; and Little Rock, Arkansas.  Photo by Keith Weller.  640 pixels wide: (k9834-1.jpg)   Please visit our Image Gallery


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