Sugar is often blamed as a short-term cause of excitability and limited attention-span in children. While there have been several studies over the last few decades attempting to link consumption of sugar and hyperactivity in children, there is little or no evidence that such a link exists.
Sugar is usually processed very quickly by the body, which can lead to a spike in blood sugar levels. This can increase activity in general by making a child feel less tired, but the same effect would be achieved by eating refined flour or other foods with a high Glycemic Index.
There has been some speculation about a link between hyperactivity and food dyes, which are often included with sugar in children's food, but this has not yet been proved definitively.
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