Quick answer
- Only melatonin has an authorised sleep claim in the EU: 1 mg close to bedtime reduces the time it takes to fall asleep. In the UK it is prescription-only, so it is not an over-the-counter option.
- Magnesium, ashwagandha, valerian and other herbs have no authorised sleep claim; the evidence ranges from modest to weak.
- For insomnia that lasts for months, the 2023 European Insomnia Guideline recommends cognitive behavioural therapy (CBT-I) first, and does not recommend fast-release melatonin or herbal remedies.
- "Sleep complexes" often combine many ingredients at low or undisclosed doses; check each one.
Key numbers
- Melatonin in the UK
- Prescription-only medicine
- UK route for chronic insomnia (NHS)
- CBT from your GP
- Sleeping pills are rarely prescribed.
- Only authorised sleep claim (EU)
- Melatonin, 1 mg
- Close to bedtime; 0.5 mg for jet lag.
- Melatonin in Spain
- below 2 mg/day
- Magnesium from supplements (EFSA safe level)
- 250 mg/day
- First-line treatment for chronic insomnia
- CBT-I
- European Insomnia Guideline, 2023.
What these terms mean: NRV upper levels (NHS, EFSA) maximum levels by country daily dose
How to choose
- Name the problem: falling asleep, waking at night, jet lag or stress. Supplements differ for each.
- For falling asleep or jet lag, melatonin at 1 mg or less, short-term, is the option with an authorised claim.
- If your diet is low in magnesium, magnesium (up to 250 mg from supplements) may help a little; it is not a sleeping pill.
- Skip ashwagandha if you are pregnant, breastfeeding or have liver or thyroid problems.
- If poor sleep lasts more than three months, or you snore loudly and feel sleepy by day, see a doctor.
Which supplement for which sleep problem
| Problem | Option with the best support | What to expect |
|---|---|---|
| Trouble falling asleep | Melatonin, 1 mg about 30 minutes before bed | Modest: a few minutes sooner on average |
| Jet lag | Melatonin, 0.5 mg on travel days | authorised claim; helps shift the body clock |
| Waking during the night | No supplement with good evidence | Prolonged-release melatonin is a medicine option for over-55s |
| Stress keeps you awake | Ashwagandha (small effect), L-theanine (small trials) | No authorised claims; check who should avoid ashwagandha |
| Diet low in magnesium | Magnesium, up to 250 mg from supplements | Small, uncertain benefit |
| Long-term insomnia | CBT-I, not a supplement | First-line treatment in the European guideline |
The table below ranks every ingredient in our goal finder for sleep by strength of evidence.
Ingredients for this goal, by strength of evidence
| Ingredient | Evidence | Authorised claim (UK/EU) | What the evidence shows |
|---|---|---|---|
| Melatonin | Strong | Yes | Authorised in the EU: 1 mg before bed shortens time to fall asleep. In the UK melatonin is prescription-only, not a supplement. |
| Magnesium | Moderate | No | Modest benefit, mainly in people who are low; no authorised sleep claim. |
| Ashwagandha | Moderate | No | Several RCTs show better sleep quality at 300–600 mg. |
| Valerian | Limited | No | Mixed results; possible small effect after 2–4 weeks. |
| Passionflower | Limited | No | Traditional use; little trial data. |
| California poppy | Limited | No | Traditional use; little trial data. |
| Lemon balm | Limited | No | Small trials, often combined with valerian. |
| Chamomile | Limited | No | Weak evidence; mild effect at best. |
| Lavender | Limited | No | Evidence is for a specific oil extract at 80 mg, not small amounts in blends. |
| 5-HTP (griffonia) | Limited | No | Little good-quality evidence for sleep. |
| L-theanine | Limited | No | Small trials on sleep quality at 200–400 mg. |
Products we have checked
Label data checked by NutriMetrics for products sold in Spain and Germany. UK product checks are next. Sorted alphabetically, not ranked.
| Product | Per daily dose | Sold in | Label |
|---|---|---|---|
| Ana María Lajusticia Bisglicinato de magnesioSee label | Magnesium: Not on the label · bisglycinate | Spain | Source |
| Aquilea Melatonina 1,95 mg1 tablet before bed | Melatonin: 1.95 mg | Spain | Source |
| Aquilea Sueño1 tablet 30 min before bed | Melatonin: Not on the label Valerian: Not on the label Passionflower: Not on the label California poppy: Not on the label | Spain | Source |
| Aquilea Sueño Forte1 tablet 30 min before bed | Melatonin: 1.95 mg 5-HTP (griffonia): Not on the label Passionflower: Not on the label California poppy: Not on the label Valerian: Not on the label Lemon balm: Not on the label | Spain | Source |
| Myprotein KSM-66 Ashwagandha1 capsule a day Retailer states 500 mg per capsule — unusual for KSM-66 (normally 300 or 600 mg). Recheck the label. | Ashwagandha: 500 mg · KSM-66 root extract (as stated by retailer) | Spain (not yet confirmed) · Germany (not yet confirmed) | Source |
| natural elements Magnesium Bisglycinat3 capsules a day | Magnesium: 300 mg · bisglycinate | Germany | Source |
| Solgar L-Theanine 150 mg2 capsules a day Listed as discontinued at a UK retailer — confirm EU availability before linking. | L-theanine: 300 mg · Suntheanine | Spain (not yet confirmed) | Source |
| Vicks / WICK (P&G) ZzzQuil Natura gummies (DE: ZzzQuil Goodnight)1 gummy 30 min before bed | Melatonin: 1 mg Valerian: 30 mg Chamomile: 10 mg Lavender: 10 mg | Germany · Spain (not yet confirmed) | Source |
| Violila Ashwagandha Opti KSM-661 capsule a day | Ashwagandha: 300 mg · KSM-66 root extract, 5% withanolides | Germany | Source |
Who should be careful
- Driving: don't drive or use machinery if you feel drowsy the next morning.
- Pregnancy, breastfeeding and children: don't use sleep supplements without medical advice.
- Sedatives, antidepressants and alcohol can interact with melatonin and several herbs.
FAQ
What is the best supplement for sleep?
In the UK, no over-the-counter supplement has an authorised sleep claim: melatonin, the only one with an authorised claim (1 mg close to bedtime), is prescription-only here. Its effect is modest anyway. For long-term insomnia, CBT-I is the recommended first treatment, and the NHS says a GP may offer it.
Does magnesium help you sleep?
Possibly a little, mainly in people who get little magnesium from food. A meta-analysis in older adults found people fell asleep about 17 minutes sooner, on low-quality evidence. There is no authorised claim in the UK or EU.
Are herbal sleep remedies like valerian effective?
The evidence is weak and inconsistent. The European Insomnia Guideline does not recommend phytotherapeutics for treating insomnia.
Sources
- NHS — Insomnia
- MHRA (August 2025) — melatonin is a prescription-only medicine
- DHSC — Great Britain nutrition and health claims (NHC) register
- Riemann D et al. The European Insomnia Guideline: an update on diagnosis and treatment of insomnia 2023. J Sleep Res, 2023
- European Commission — EU Register of nutrition and health claims (melatonin)
- Ferracioli-Oda E et al. Meta-analysis — melatonin for the treatment of primary sleep disorders. PLoS One, 2013
- Mah J, Pitre T. Oral magnesium supplementation for insomnia in older adults. BMC Complement Med Ther, 2021
- Cheah KL et al. Effect of ashwagandha extract on sleep — systematic review and meta-analysis. PLoS One, 2021
Information only, not medical advice. No product on this page is a paid placement.