White bread or whole-wheat? It may depend on your gut

By Lisa Drayer, CNN

Updated 0747 GMT (1547 HKT) June 16, 2017

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It's thumbs up today, but the news on carbs has not always been positive. Take a look at the arguments for and against carbohydrates through the centuries:
Photos: Carbohydrates' health history
Carbohydrates' health history: Where do we stand now? – It's thumbs up today, but the news on carbs has not always been positive. Take a look at the arguments for and against carbohydrates through the centuries:
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Eating a healthy portion of carbohydrates might have been critical for our evolution into a highly intelligent species.
Photos: Carbohydrates' health history
2 million B.C.: Man cannot live on meat alone – Eating a healthy portion of carbohydrates might have been critical for our evolution into a highly intelligent species.
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Bread and beer were staple foods in ancient Egypt and Greece. Pictured is a limestone statuette of an Egyptian servant pressing out the fermented barley-bread from which beer was brewed.
Photos: Carbohydrates' health history
3,000 B.C.: Thank the gods for bread – Bread and beer were staple foods in ancient Egypt and Greece. Pictured is a limestone statuette of an Egyptian servant pressing out the fermented barley-bread from which beer was brewed.
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American inventor Otto Rohwedder developed the first mechanic bread slicer. By the end of the 1920s, 90% of store-bought bread came sliced.
Photos: Carbohydrates' health history
Early 20th century: Sliced bread is the best thing since ... ever – American inventor Otto Rohwedder developed the first mechanic bread slicer. By the end of the 1920s, 90% of store-bought bread came sliced.