Attitudes may change when the next wave of genetically modified foods, which have been engineered for consumer-friendly traits such as higher vitamin content, emerge from the laboratory.

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These plastics not only serve as superior barriers to the flow of oxygen and carbon dioxide, keeping all kinds of products fresher longer, but also block out smells and prevent the packaging from absorbing any of the flavor or vitamin content of the food.

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The laws have been designed to regulate vitamin and mineral content, to protect consumers from overdosing.

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In January 2000 the FDA slapped him with a warning letter for overhyping the vitamin B-12 content in Spirulina Spirals and wrongly promoting Fruity Booty as a "mostly fruit" product when the only fruit to be found in it was a powdered dust of flavorings.

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In addition, vitamin D can be produced by the skin with sunlight exposure, but this ability decreases with age and varies considerably by geography, time of day or year, skin melanin content (darker skin produces less vitamin D) and sunscreen use.

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It is a good idea to read nutrition content on food labels to see if you are getting enough vitamin D, calcium or magnesium.

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