Methodology

Why answers are split by goal

“Does this break my fast?” has no single answer. It depends on what you are fasting for. A substance can be irrelevant to a calorie deficit, disqualifying for autophagy, and forbidden before a blood test, all at once. Collapsing that into one yes or no is the most common mistake made by pages answering this question, so every entry here is split by goal.

Evidence

Answers are grounded in primary research where it exists, cited inline. Where the evidence is thin, mixed, or drawn only from animal studies, the entry says so rather than choosing a confident answer.

Review

Entries are checked by a credentialed reviewer before publication, and carry that reviewer’s name and the date. Entries that have not yet been reviewed are marked as drafts and excluded from search engines.

How this site makes money

Fasting Index sells no supplements and takes no affiliate revenue from any product it writes about. This is a permanent constraint, not a current state of affairs. The reason is simple: nearly every page currently ranking for these questions is published by a company selling the product in question, and an independent answer is only worth something if it stays independent.

What this site is not

It is not medical advice. Fasting is not safe for everyone, and it is specifically not safe for some people who are pregnant, taking medication, or managing a medical condition. Where a question is medical, such as fasting before surgery or blood work, the honest answer is to follow your clinic.