Pharmacy guide

Fasting is abstinence from food or drink or both. It’s practised for many different reasons.

Pharmacists and their teams may be asked about fasting and its effects on medicine use or health.

Use this guide to find out more and support people who fast.

First Published: 9 February 2022
Updated: 10 January 2023


Sections on this page 

  • Why do people fast?
  • How long do people fast for?
  • Effects of fasting on the body
  • Benefits and risks of fasting
  • Who should not fast?
  • Practical tips to support people who fast 
  • Workplace considerations 
  • General considerations 
  • Advice for people who fast 
  • Diet advice
  • Exercise advice 
  • Smoking cessation advice
  • Medicine use 
  • Further information

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