Supplements
Vitamin D under NHS guidance, omega-3 research, magnesium forms, MHRA Yellow Card framing.
If you only read one
Vitamin B12: where deficiency lives and who should supplement
B12 deficiency causes neurological damage that can become irreversible. The populations at risk are well-defined: vegans, vegetarians with limited dairy/egg, older adults with reduced absorption, and people on metformin or proton-pump inhibitors.
Grade A · 3 min read · Last reviewed 2026-05-19
Ashwagandha at the supplement aisle: a practical buyer's overview
Evidence BAshwagandha is one of the few adaptogens with real RCT evidence — but the supplement aisle is messier than the trial literature. Standardisation, quality, the liver injury signal, and what to actually look for.
4 min read · Last reviewed 2026-05-19
Vitamin B12: where deficiency lives and who should supplement
Evidence AB12 deficiency causes neurological damage that can become irreversible. The populations at risk are well-defined: vegans, vegetarians with limited dairy/egg, older adults with reduced absorption, and people on metformin or proton-pump inhibitors.
3 min read · Last reviewed 2026-05-19
Berberine as a supplement: lipid, glucose, and the regulatory grey area
Evidence CBerberine has solid trial evidence for lipids and modest glucose effects. The supplement-aisle framing differs from the CGM page — here we look at it as a lipid-and-glucose tool, the interaction risks, and the UK regulatory status.
3 min read · Last reviewed 2026-05-19
Collagen peptides: between the marketing and the trial evidence
Evidence CCollagen peptides are widely sold for skin, joints, and hair. The trial evidence is meaningfully smaller than the marketing implies — what's actually replicated, what isn't, and what to expect.
4 min read · Last reviewed 2026-05-19
Creatine for women: the evidence beyond muscle
Evidence BMost creatine research is in men, but a meaningful body of evidence in women shows benefits for strength, bone health, mood, and cognition — particularly across hormonal life stages.
4 min read · Last reviewed 2026-05-19
Iron deficiency: testing, supplementation, and when not to supplement
Evidence AIron deficiency is one of the most common nutritional deficiencies worldwide but supplementing without it being needed carries real risk. What the NHS thresholds are, how to test, and the rules of safe supplementation.
4 min read · Last reviewed 2026-05-19
Magnesium forms: which one to pick and what the bioavailability data actually shows
Evidence BGlycinate, citrate, oxide, threonate, malate — the differences between magnesium supplement forms in absorption, GI tolerance, and where the real differences lie.
3 min read · Last reviewed 2026-05-17
Multivitamins: what 30 years of large trials actually show
Evidence BMultivitamins are the most-taken supplement in the UK. The trial evidence on hard outcomes is more nuanced than most readers expect — small effects in specific contexts, none in well-nourished healthy adults.
3 min read · Last reviewed 2026-05-19
Omega-3: what the research currently supports
Evidence BEPA and DHA from fish oil are among the most-studied supplements. What the cardiovascular, cognitive, and mental-health literature actually says, and the dose ranges that come up in trials.
3 min read · Last reviewed 2026-05-17
Probiotics: strain specificity, what's evidenced, and what isn't
Evidence CThe probiotics market sells 'gut health' as a single category. The trial evidence is strain-specific and indication-specific — what's actually evidenced for diarrhoea, IBS, and antibiotic-associated diarrhoea, and what isn't.
3 min read · Last reviewed 2026-05-19
Vitamin D in the UK: NHS guidance, evidence, and reasonable doses
Evidence AThe UK has explicit Public Health England guidance on vitamin D supplementation during autumn and winter. Here's the published advice, the evidence behind it, and what to know before going higher.
3 min read · Last reviewed 2026-05-17
Vitamin K2: the supplement often paired with vitamin D
Evidence CVitamin K2 is widely marketed as essential alongside vitamin D supplementation. The cardiovascular and bone-health evidence is interesting but smaller than the supplement-shop confidence implies.
3 min read · Last reviewed 2026-05-18
Reporting supplement side effects: how the MHRA Yellow Card scheme works
Evidence AAnyone in the UK can report a suspected side effect from a medicine or supplement to the MHRA. Here's what the Yellow Card scheme covers, what it doesn't, and why it matters for the supplement market.
3 min read · Last reviewed 2026-05-17
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