"Clinically Proven" vs "Clinically Tested": How to Read Supplement Claims

"Clinically proven" is not a regulated term, and in the UK a food supplement cannot claim to prove anything about health beyond the approved claims on the GB register. To judge any research claim, ask four questions: what was tested, who ran the study, how big it was, and whether it was peer-reviewed.

What UK rules allow

Health claims for food supplements in Great Britain must come from the GB nutrition and health claims register, word for word, for nutrients present at a meaningful amount. "Vitamin C contributes to the normal function of the immune system" is allowed. "Clinically proven to boost immunity" is not.

Four questions to ask about any study

1. What was tested? The whole product, or one ingredient? A result for vitamin C says nothing about magnesium.
2. Who ran it and who paid? Manufacturer studies can be sound, but independent research carries more weight.
3. How big and how designed? A randomised, controlled trial in hundreds of people beats an uncontrolled test in ten.
4. Was it peer-reviewed and published? If you cannot find it, treat the claim with caution.

Types of evidence, strongest first

• Systematic reviews and meta-analyses that pool several trials.
• Randomised controlled trials, ideally double-blind.
• Smaller or uncontrolled human studies.
• Lab and animal studies, which do not tell you what happens in people.
• Manufacturer white papers that have not been peer-reviewed.

What our own claims are based on

We hold ourselves to the same questions.

• "Up to 5x better absorption" comes from clinical testing of our liposomal delivery format compared with a standard capsule.
• "Up to 12x higher absorption" comes from a study by our manufacturer on liposomal vitamin C only, in 40 healthy volunteers. It has not been independently peer-reviewed, and it does not apply to the full formula or to magnesium.
• Independent evidence: a 2025 scoping review found 9 of 10 human studies showed higher bioavailability for liposomal vitamin C than standard vitamin C.
• Magnesium: we do not claim a magnesium-specific absorption figure. One independent trial found no significant difference between liposomal and standard magnesium over six hours.

Red flags

• "Clinically proven" with no study named.
• One ingredient's result applied to a whole product.
• Proprietary blends that hide doses.
• Claims to treat, prevent or cure anything. Supplements cannot legally make them.

Where Absorble fits

Every dose in the Daily Shot and Evening Shot is listed on our ingredients page, with the approved claim for each nutrient.

Keep reading

• Liposomal vitamins, explained
• Liposomal vitamin C: what the evidence says
• How we formulated Absorble

Sources

• GOV.UK: Great Britain nutrition and health claims register
• Carr AC (2025). Do liposomal vitamin C formulations have improved bioavailability? A scoping review. Basic & Clinical Pharmacology & Toxicology
• Evaluation and clinical comparison studies on liposomal and non-liposomal ascorbic acid and their enhanced bioavailability (PubMed 32901526)
• Tinsley et al. (2022). Liposomal iron and magnesium absorption, Nutrients (PubMed 36014827)
• Ko et al. (2023). Liposomal and non-liposomal multi-nutrient absorption, Nutrients (PubMed 37447400)

This guide is for general information and is not medical advice. Food supplements should not replace a varied, balanced diet and a healthy lifestyle. If you are pregnant, breastfeeding, taking medication or have a medical condition, speak to your GP or pharmacist before taking a new supplement.