What is intermittent fasting, and is it healthy?

Photos: American diet trends
The good news: Americans are consuming fewer calories. The bad news: Americans still have a long way to go in how they divvy up calories.
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Photos: American diet trends
Water over sugary drinks – Americans in almost every age and ethnic group have been weaning themselves off soda and fruit drinks and substituting for healthier choices like water.
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Photos: American diet trends
Not enough fruits and veggies – Increasing our intake of fruits and veggies could play a part in improving the U.S. diet. There has been only a slight uptick in consumption of these healthy foods since 2003.
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Photos: American diet trends
Trans fats decrease – Americans have made huge strides in improving their diet by eliminating trans fats -- although much of that is due to changes in the manufacturing process.
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Photos: American diet trends
No budging on fast food – Despite all the reports of fast food's ill effects on health, Americans have been only slightly scaling back their intake.
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Photos: American diet trends
Going nuts –