Why do we drool before being sick?

Asked by: Nicola Bain, Glasgow

Vomiting is a deliberate response by the body that evolved as a purging mechanism to remove toxins or foreign bodies from the stomach and oesophagus. Since stomach contents are highly acidic, vomiting can be quite harmful for the throat, mouth and teeth and salivating helps to reduce this by diluting and rinsing.

Saliva is also weakly alkaline, which helps to neutralise acid.

Read more:

• Why is rice such a food-poisoning culprit?
• What happens in my body when I vomit?

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