Why does orange juice taste bad after tooth brushing?

Asked by: Nigel Ngwenya, Leeds

Toothpaste contains sodium lauryl sulfate (SLS) that creates bubbles when you brush. But it suppresses sweet receptors on the tongue, which prevents the brain from registering sweetness, and destroys compounds in the saliva called phospholipids, which block bitter receptors. So SLS not only cuts orange juice’s sweetness, but promotes its natural bitterness, too.

Read more:

• What’s in toothpaste?
• Does flossing your teeth really make a difference?

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