Our Methodology

Peak Health Stack applies a consistent methodology to every piece of content we publish. Our goal is to give you accurate, useful health information — which means being transparent about how we evaluate evidence, how we write about uncertainty, and where the limits of our knowledge lie.

Evidence Hierarchy

We evaluate health claims using the standard medical evidence hierarchy. The strongest evidence comes from systematic reviews and meta-analyses of multiple randomised controlled trials — these aggregate findings across thousands of participants and account for study-to-study variation. Below these sit individual double-blind RCTs, then observational cohort studies, then mechanistic research and expert opinion. We distinguish between these tiers in our content and always state which type of evidence supports a given claim.

When the evidence base is strong and consistent, we say so directly. When a supplement has promising mechanistic or early-stage evidence but lacks large human RCTs, we say that too. We do not present animal study findings or in-vitro research as human clinical evidence. We do not extrapolate from proxy measures to clinical outcomes without flagging the gap.

Sources We Use

Our primary sources are peer-reviewed research published on PubMed, clinical guidelines from the NHS, NIH, and equivalent health authorities, and Cochrane systematic reviews where available. We do not cite manufacturer-funded studies as the sole basis for a recommendation without noting the funding source and any conflict of interest. Where studies have small sample sizes, short durations, or specific population characteristics that limit generalisability, we note this explicitly.

How We Assess Supplements

For each supplement we cover, we evaluate: the mechanism of action (how it works biologically), the quality and consistency of clinical trial evidence, the population studied (healthy adults, specific conditions, age groups), the dose and form used in trials versus what is commercially available, the safety profile and known interactions, and the cost-to-benefit ratio relative to alternative approaches.

We pay particular attention to form — because the form of a supplement frequently determines whether it is absorbed and utilised at all. Magnesium oxide absorbs at approximately 4%; magnesium glycinate absorbs at 80%+. Cyanocobalamin B12 is significantly less bioavailable in older adults than methylcobalamin. These distinctions matter enormously for whether a supplement produces the outcome attributed to it, and we cover them in every relevant guide.

Health Disclaimers and Medical Advice

Peak Health Stack provides health information for educational purposes. Our content is not medical advice, and nothing on this site should be used as a substitute for consultation with a qualified healthcare professional. We always recommend speaking with your GP or a registered dietitian before starting any new supplement regimen — particularly if you have an existing health condition, are pregnant or breastfeeding, or are taking prescription medication.

We are especially careful with content in YMYL (Your Money or Your Life) categories — health, medical, and financial information where inaccurate guidance could cause real harm. Our supplement guides include dosing information sourced directly from clinical trials and note upper safe limits where these have been established.

Keeping Content Current

The evidence base for supplements and nutritional interventions evolves. We review our core supplement guides regularly and update them when new meta-analyses, large RCTs, or changes to clinical guidelines materially affect the recommendations. Publication and update dates are noted on all content. If you spot an error or outdated reference, contact us — we take corrections seriously.

Affiliate Relationships and Editorial Independence

Some links on Peak Health Stack are affiliate links. These relationships never determine what we recommend — we choose products based on evidence quality, formulation, and value, not on the size of the affiliate commission. See How We Make Money for full disclosure of our commercial relationships.