Skip to content
BestCapsules

Find capsules by goal

Say what you want help with. The finder shows what the GB register lets any seller claim for it, what the register assessed and refused, and the cheapest capsules per capsule for each ingredient. It quotes; it never advises.

What do you want help with?

Where the register allows less than sellers suggest

Anything you already take or are considering?

Name it and the finder says whether the register authorises any claim for it for your goals, or refused one, or has never assessed it.

  • None yet. Type an ingredient in the box above, for example “magnesium” or “turmeric”.

Preferences

Seller-stated only: vegan means the seller says vegan.

Digestion and Immunity and Testosterone and Tiredness and fatigue

1550 capsules across 68 ingredients

Digestion. The register authorises specific wording about digestion for a few nutrients, quoted exactly on their pages, and refused most of the probiotic and gut wording sellers reach for. The split below is the honest picture. Persistent digestive symptoms are a matter for a GP, and Guts UK is the specialist charity.

Immunity. This page gathers ingredients whose GB register claims relate to the normal function of the immune system, with the exact authorised wording quoted on each ingredient page. Anything not authorised may not be claimed by sellers, and we quote that status too. A balanced diet, sleep and vaccination advice from the NHS come before any capsule.

Testosterone. Only a small number of ingredients hold register claims mentioning testosterone, and this page quotes them exactly. Claims in this category are heavily marketed well beyond what the register authorises; the split below shows the line.

Tiredness and fatigue. The register's phrase is 'a reduction of tiredness and fatigue', and a surprising number of everyday nutrients hold that authorised wording. This page shows which, quoted exactly, alongside ingredients people discuss without an authorised claim. Persistent tiredness is worth raising with a GP; the NHS link below covers self-help basics.

Nothing here is medical advice. The wording is the GB register's, quoted exactly; whether a product qualifies to use it is the seller's responsibility. Speak to a GP or pharmacist before taking a supplement, especially if you are pregnant, take medicines or have a diagnosed condition. Wording from the GB nutrition and health claims register; mapping reviewed 4 September 2026.

Holds an authorised claim

Magnesium

1 authorised claim · 334 capsules · ingredient page
  • “Magnesium contributes to a reduction of tiredness and fatigue” · Tiredness and fatigue

Not authorised for immunity: the register refused 1 claim there.

All 334 magnesium capsules

Vitamin C

3 authorised claims · 332 capsules · ingredient page
  • “Vitamin C contributes to maintain the normal function of the immune system during and after intense physical exercise” · Immunity
  • “Vitamin C contributes to the normal function of the immune system” · Immunity
  • “Vitamin C contributes to the reduction of tiredness and fatigue” · Tiredness and fatigue

Not authorised for tiredness and fatigue: the register refused 1 claim there.

All 332 vitamin c capsules

Zinc

2 authorised claims · 249 capsules · ingredient page
  • “Zinc contributes to the normal function of the immune system” · Immunity
  • “Zinc contributes to the maintenance of normal testosterone levels in the blood” · Testosterone

Not authorised for tiredness and fatigue: the register refused 1 claim there.

All 249 zinc capsules

Vitamin D

2 authorised claims · 232 capsules · ingredient page
  • “Vitamin D contributes to the normal function of the immune system” · Immunity
  • “Vitamin D contributes to the normal function of the immune system in children.” · Immunity

All 232 vitamin d capsules

Vitamin B6

2 authorised claims · 185 capsules · ingredient page
  • “Vitamin B6 contributes to the normal function of the immune system” · Immunity
  • “Vitamin B6 contributes to the reduction of tiredness and fatigue” · Tiredness and fatigue

All 185 vitamin b6 capsules

Vitamin B12

2 authorised claims · 163 capsules · ingredient page
  • “Vitamin B12 contributes to the normal function of the immune system” · Immunity
  • “Vitamin B12 contributes to the reduction of tiredness and fatigue” · Tiredness and fatigue

Not authorised for tiredness and fatigue: the register refused 1 claim there.

All 163 vitamin b12 capsules

Folate

2 authorised claims · 138 capsules · ingredient page
  • “Folate contributes to the normal function of the immune system” · Immunity
  • “Folate contributes to the reduction of tiredness and fatigue” · Tiredness and fatigue

All 138 folate capsules

Calcium

1 authorised claim · 96 capsules · ingredient page
  • “Calcium contributes to the normal function of digestive enzymes” · Digestion

Not authorised for tiredness and fatigue: the register refused 1 claim there.

All 96 calcium capsules

Selenium

1 authorised claim · 95 capsules · ingredient page
  • “Selenium contributes to the normal function of the immune system” · Immunity

All 95 selenium capsules

Iron

2 authorised claims · 87 capsules · ingredient page
  • “Iron contributes to the normal function of the immune system” · Immunity
  • “Iron contributes to the reduction of tiredness and fatigue” · Tiredness and fatigue

All 87 iron capsules

Copper

1 authorised claim · 58 capsules · ingredient page
  • “Copper contributes to the normal function of the immune system” · Immunity

Not authorised for tiredness and fatigue: the register refused 1 claim there.

All 58 copper capsules

Vitamin A

1 authorised claim · 54 capsules · ingredient page
  • “Vitamin A contributes to the normal function of the immune system” · Immunity

Not authorised for tiredness and fatigue: the register refused 1 claim there.

All 54 vitamin a capsules

Niacin

1 authorised claim · 46 capsules · ingredient page
  • “Niacin contributes to the reduction of tiredness and fatigue” · Tiredness and fatigue

All 46 niacin capsules

Pantothenic Acid

1 authorised claim · 36 capsules · ingredient page
  • “Pantothenic acid contributes to the reduction of tiredness and fatigue” · Tiredness and fatigue

All 36 pantothenic acid capsules

Riboflavin

1 authorised claim · 36 capsules · ingredient page
  • “Riboflavin contributes to the reduction of tiredness and fatigue” · Tiredness and fatigue

All 36 riboflavin capsules

Activated Charcoal

1 authorised claim · 17 capsules · ingredient page
  • “Activated charcoal contributes to reducing excessive flatulence after eating” · Digestion

Not authorised for digestion: the register refused 1 claim there.

All 17 activated charcoal capsules

Chloride

1 authorised claim · 5 capsules · ingredient page
  • “Chloride contributes to normal digestion by production of hydrochloric acid in the stomach” · Digestion

All 5 chloride capsules

sugar beet fibre

1 authorised claim · 4 capsules · ingredient page
  • “Sugar beet fibre contributes to an increase in faecal bulk” · Digestion

Not authorised for digestion: the register refused 2 claims there.

All 4 sugar beet fibre capsules

Lactase enzyme

1 authorised claim · 3 capsules · ingredient page
  • “Lactase enzyme improves lactose digestion in individuals who have difficulty digesting lactose” · Digestion

All 3 lactase enzyme capsules

Assessed by the register and not authorised

The register looked at claims for these relating to digestion and immunity and testosterone and tiredness and fatigue and turned them down. Sellers may not make them. Prices are shown for ingredients you named; the rest link to their register page.

Support & information

Independent organisations for support and reliable information; none endorses any product on this site.