Comparison

THE FAD vs. AIP (Autoimmune Protocol)

A medically-oriented protocol for a diagnosed condition — not something THE FAD replaces.

The Autoimmune Protocol (AIP) is a structured elimination diet specifically designed for people with diagnosed autoimmune conditions, removing a broader list of potentially inflammatory foods than most general diets before a careful, personalised reintroduction phase.

DimensionAIP DietTHE FAD
Core ruleAn elimination-and-reintroduction protocol removing grains, legumes, dairy, nightshades, eggs and more, then personalising a maintenance dietNo elimination phase — ongoing daily scoring of whatever you already eat
Who it's forPeople with a diagnosed autoimmune condition, ideally working with a healthcare providerGeneral population lifestyle tracking
Evidence baseSmall, promising pilot studies (inflammatory bowel disease, Hashimoto's) — genuinely early-stage, not yet large-scale confirmedDraws on broader, more established general nutrition and inflammation research

What the research actually shows

Small pilot studies — including an 11-week study in people with inflammatory bowel disease — have found meaningful symptom improvement for some participants, and a 2024 scientific review described the evidence as promising but still early, with most studies small and uncontrolled. This is genuinely encouraging, not yet confirmed at the scale you'd want before broad clinical recommendations.

Why THE FAD isn't a substitute for AIP

AIP is a targeted, medically-oriented elimination protocol for a diagnosed condition — see our autoimmune conditions page. THE FAD's general Food signal doesn't replace the personalised, supervised elimination-and-reintroduction process AIP requires; if you have an autoimmune diagnosis and are considering AIP, that's a conversation for your doctor or a registered dietitian.

See your own comparison

The best way to understand the difference is to see what a real day scores.

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