Intermittent fasting for beginners
– the evidence

 
Our intermittent fasting guide is based on scientific evidence, following our policy for evidence-based guides.

It’s written by Dr. Jason Fung, MD. The latest major update was on March 5, 2019, after a thorough review and fact-checking by Franziska Spritzler, RD, and further research and fact-checking by Pauls Rutkovskis.1

The guide was medically reviewed by Dr. Andreas Eenfeldt, MD, on March 5, 2019.

The guide contains scientific references. You can find these in the notes throughout the text, and click the links to read the peer-reviewed scientific papers. When appropriate we include a grading of the strength of the evidence, with a link to our policy on this. Our evidence-based guides are updated at least once per year to reflect and reference the latest science on the topic.

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Read more about our policies and work with evidence-based guides, nutritional controversies, our writers team and our medical review board.

Disclaimer: While intermittent fasting has many proven benefits, it’s still controversial. A potential danger regards medications, especially for diabetes, where doses often need to be adapted. Discuss any changes in medication and relevant lifestyle changes with your doctor. Full disclaimer

This guide is written for adults with health issues, including obesity, that could benefit from intermittent fasting.

People who should NOT fast include those who are underweight or have eating disorders like anorexia, women who are pregnant or breastfeeding, and people under the age of 18.

 
Should you find any inaccuracy in this food policy, please email andreas@dietdoctor.com.

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  1. The latest update includes a large number of modest changes in the text and the addition of many scientific references.

  2. A full declaration of potential conflicts of interests of individual authors or reviewers can be found on their personal pages, linked from their names.

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