How to choose a supplement
Ask six things: do I need it, is the dose sensible, is the form one I will take, does it have evidence, is it safe for me, and what does it cost per day?.
Short answer Ask six things: do I need it, is the dose sensible, is the form one I will take, does it have evidence, is it safe for me, and what does it cost per day?
The six questions
| Question | How to answer it |
|---|---|
| Do I need it? | Check UK guidance and your diet first |
| Is the dose sensible? | Near reference values, not many multiples |
| Is the form right? | Tablet, capsule, powder or liquid you will use |
| Is there evidence? | Look for authorised claims, not adjectives |
| Is it safe for me? | Medicines, pregnancy, conditions, allergies |
| Cost per day? | Price divided by days of use |
Red flags
Promises to treat or cure, 'miracle' or 'detox', before-and-after photos, no ingredient amounts, and sellers you cannot identify.
Where to buy
From a known retailer or the brand itself. Be careful with marketplaces, where counterfeit and unregulated products appear.
Related pages
- Supplement safetyMost supplements are safe at the stated dose for healthy adults.
- Health claims explainedIn Great Britain a supplement may only make a health claim that appears on the official nutrition and health claims register, and may never claim to prevent, treat or cure a disease.
- Vitamins and mineralsMost people can get the vitamins and minerals they need from a varied diet.
Keep exploring
- Vitamins for over 50s
- Turmeric and curcumin
- Collagen peptides
- Hair, skin and nail vitamins
- Guides
- Collagen types 1, 2 and 3
Questions people ask
How do I know if a supplement is good quality?
Clear amounts, a named manufacturer, sensible doses and batch testing are good signs.
Can I take this with medication?
Ask a pharmacist or GP first; some supplements interact with medicines.
Do supplements replace a balanced diet?
No. They are meant to add to a varied diet, not stand in for one.
Sources
- NHS: Vitamins and minerals (opens in a new tab)
- Great Britain nutrition and health claims register (opens in a new tab)
Checked 9 October 2026.