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How we research and check these guides

Every guide is built from official sources you can open yourself. Here is the process, and its limits.

Official sources first

We rely on government health agencies: the U.S. National Institutes of Health, FDA and CDC, MedlinePlus, the UK's NHS and Food Standards Agency, and Spain's Ministry of Social Rights, Consumer Affairs and the 2030 Agenda (with recommendations from the food safety agency AESAN). Each guide ends with a Sources list linking to the exact pages used, with the page's own date when it shows one.

We read the page before we link it

A source is cited only if its page was opened and read. If a page cannot be opened, we do not cite it. We cite journal studies only after reading them, and we say when a source does not address a question.

Countries disagree, and we say so

Recommended amounts and rules differ between the United States, the UK and Spain. Where they do, the guide names the agency instead of presenting one number as universal.

What we leave out

We do not make claims that a product treats, cures or prevents disease, and we do not give personal doses. Dose and medication questions belong with your doctor or pharmacist.

How the guides are written

The guides are drafted with the help of Claude, an AI assistant made by Anthropic, which reads the source pages and helps write the summaries. AI can make mistakes, which is why every claim points to a source you can check.

Reviews and corrections

Each guide shows a "last reviewed" date, which is updated when its sources are re-checked. These guides have not been reviewed by a doctor, pharmacist or dietitian. If you spot an error, tell us using the email button in the contact section and we will correct it.

Amazon and allergens

Product pages on Amazon are written by sellers. Amazon does not verify allergen or health claims, so always read the ingredient list and allergen statement on the product itself.