NutriStack
Strong
Multiple high-quality RCTs or meta-analyses.
Effect has been replicated in independent randomized trials or pooled in systematic reviews. The biological mechanism is well-understood. The highest tier we assign.
Every score on NutriStack is a calculation, not a vibe. Every interaction is a row in a database with a citation. This page is the receipt for both.
NutriStack is independently owned.
No manufacturer payments. No affiliate revenue. No celebrity protocols.
Stack Score
Your Stack Score starts at 70 and moves based on the pairwise interactions in your stack. The math is below; the source code lives in the app.
Composite formula
The final score is clamped to 0–100 so no single conflict can drive it below zero.
Worked example
A stack of Vitamin D3, Vitamin K2, Magnesium, Vitamin C, Iron, Zinc, and L-Theanine produces 6 synergies and 0 conflicts.
This is the same math you can verify by tapping any pair in the in-app Stack screen.
A note on the in-app combined score
The in-app Protocol Score blends this interaction-derived score (40% weight) with adherence (40%) and stack diversity (20%, capped at 10 supplements). The score on the homepage demo and on every per-stack page on this site is the interaction-derived score above, because that is the one computable from a public stack with no personal logging data.
Read the Stack Score deep dive → The full switch statement, four worked stacks, and the clamp-at-zero edge case.
Interactions
The interaction database is the heart of the app. Here is exactly what is in it and where every entry came from.
Each interaction row contains
Where the data comes from
Every interaction is sourced from peer-reviewed primary literature: PubMed-indexed studies, Cochrane reviews, FDA drug labels, and curated pharmacology references. We do not source from supplement company marketing pages, blog posts, or testimonials.
Citations include the study text, PMID (for PubMed-indexed studies), and DOI where available. Most rows include the strongest 2–4 studies behind that specific interaction. The full set of source links is browsable at /research/interactions.
Try the free interaction checker → Pick any two of 370 substances and see the documented interaction, the verdict, and the citations.
Read the interactions deep dive → A real row's full JSON, sourcing standards, and five named interactions with PMIDs.
Evidence tiers
Every claim, supplement profile, and interaction carries a tier. Tiers are not letter grades and not stars. Here is what each one means.
Strong
Effect has been replicated in independent randomized trials or pooled in systematic reviews. The biological mechanism is well-understood. The highest tier we assign.
Moderate
Multiple studies point the same direction, often including at least one RCT. Some questions about dose, population, or duration may remain open.
Emerging
Smaller studies, single trials, or strong mechanistic evidence without large-scale confirmation yet. Flagged clearly so hope is not mistaken for proof.
Limited
Only a handful of studies exist, the results disagree, or the study designs were weak. We say so plainly rather than averaging the noise into a confident-sounding score.
Traditional
Centuries of traditional use, often in Ayurveda or TCM, but minimal randomized evidence in modern populations. Reserved for substances with that specific profile.
Read the evidence-tiers deep dive → Explicit criteria per tier, real named examples, the database shape, and the public downgrade policy.
Updates
The database ships with the app, and every app update can refresh it.
Conflicts policy
The conflicts of interest we will not have.
See it in practice
The worked example on the homepage walks through Atorvastatin + Coenzyme Q10 in the same shape used across the database: what is happening, the mechanism, the recommendation, and the primary literature.
NutriStack is an informational and organizational tool, not a medical service, and not a substitute for professional advice. Always consult a qualified healthcare professional before starting, stopping, or changing any supplement or medication.