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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.

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Where the register allows less than sellers suggest

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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.

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

Metabolism and Focus and Immunity and Libido

1573 capsules across 69 ingredients

Metabolism. The register's phrase is 'contributes to normal energy-yielding metabolism', and many everyday vitamins and minerals hold it. It is not a claim about weight or about feeling energetic, which is why this goal sits apart from Weight and from Tiredness and fatigue. Wording is quoted exactly on each ingredient page.

Focus. Some nutrients hold register claims relating to normal cognitive or psychological function, quoted exactly on their pages. The wording is precise and worth reading as written; anything beyond it is marketing, not authorised claim.

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.

Libido. Almost no ingredient holds an authorised register claim in this area, which is itself useful information: sellers may not claim what is not authorised. What people discuss appears below with its actual register status.

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 normal energy-yielding metabolism” · Metabolism

Not authorised for immunity or metabolism: the register refused 3 claims 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 normal energy-yielding metabolism” · Metabolism

All 332 vitamin c capsules

Zinc

6 authorised claims · 249 capsules · ingredient page
  • “Zinc contributes to the normal function of the immune system” · Immunity
  • “Zinc contributes to normal cognitive function” · Focus
  • “Zinc contributes to normal carbohydrate metabolism” · Metabolism
  • “Zinc contributes to normal macronutrient metabolism” · Metabolism
  • and 2 more on the ingredient page

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

4 authorised claims · 185 capsules · ingredient page
  • “Vitamin B6 contributes to the normal function of the immune system” · Immunity
  • “Vitamin B6 contributes to normal energy-yielding metabolism” · Metabolism
  • “Vitamin B6 contributes to normal homocysteine metabolism” · Metabolism
  • “Vitamin B6 contributes to normal protein and glycogen metabolism” · Metabolism

All 185 vitamin b6 capsules

Vitamin B12

3 authorised claims · 163 capsules · ingredient page
  • “Vitamin B12 contributes to the normal function of the immune system” · Immunity
  • “Vitamin B12 contributes to normal energy-yielding metabolism” · Metabolism
  • “Vitamin B12 contributes to normal homocysteine metabolism” · Metabolism

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 normal homocysteine metabolism” · Metabolism

All 138 folate capsules

Biotin

2 authorised claims · 124 capsules · ingredient page
  • “Biotin contributes to normal energy-yielding metabolism” · Metabolism
  • “Biotin contributes to normal macronutrient metabolism” · Metabolism

All 124 biotin capsules

Calcium

1 authorised claim · 96 capsules · ingredient page
  • “Calcium contributes to normal energy-yielding metabolism” · Metabolism

Not authorised for focus or metabolism: the register refused 2 claims there.

All 96 calcium capsules

Selenium

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

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

All 95 selenium capsules

Iron

4 authorised claims · 87 capsules · ingredient page
  • “Iron contributes to the normal function of the immune system” · Immunity
  • “Iron contributes to normal cognitive function” · Focus
  • “Iron contributes to normal cognitive development of children” · Focus
  • “Iron contributes to normal energy-yielding metabolism” · Metabolism

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

All 87 iron capsules

Chromium

1 authorised claim · 62 capsules · ingredient page
  • “Chromium contributes to normal macronutrient metabolism” · Metabolism

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

All 62 chromium capsules

Copper

2 authorised claims · 58 capsules · ingredient page
  • “Copper contributes to the normal function of the immune system” · Immunity
  • “Copper contributes to normal energy-yielding metabolism” · Metabolism

All 58 copper capsules

Vitamin A

2 authorised claims · 54 capsules · ingredient page
  • “Vitamin A contributes to the normal function of the immune system” · Immunity
  • “Vitamin A contributes to normal iron metabolism” · Metabolism

All 54 vitamin a capsules

Choline

2 authorised claims · 49 capsules · ingredient page
  • “Choline contributes to normal homocysteine metabolism” · Metabolism
  • “Choline contributes to normal lipid metabolism” · Metabolism

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

All 49 choline capsules

Niacin

1 authorised claim · 46 capsules · ingredient page
  • “Niacin contributes to normal energy-yielding metabolism” · Metabolism

All 46 niacin capsules

Iodine

2 authorised claims · 45 capsules · ingredient page
  • “Iodine contributes to normal cognitive function” · Focus
  • “Iodine contributes to normal energy-yielding metabolism” · Metabolism

All 45 iodine capsules

Pantothenic Acid

3 authorised claims · 36 capsules · ingredient page
  • “Pantothenic acid contributes to normal mental performance” · Focus
  • “Pantothenic acid contributes to normal energy-yielding metabolism” · Metabolism
  • “Pantothenic acid contributes to normal synthesis and metabolism of steroid hormones, vitamin D and some neurotransmitters” · Metabolism

All 36 pantothenic acid capsules

Riboflavin

2 authorised claims · 36 capsules · ingredient page
  • “Riboflavin contributes to normal energy-yielding metabolism” · Metabolism
  • “Riboflavin contributes to the normal metabolism of iron” · Metabolism

All 36 riboflavin capsules

Manganese

1 authorised claim · 32 capsules · ingredient page
  • “Manganese contributes to normal energy-yielding metabolism” · Metabolism

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

All 32 manganese capsules

Molybdenum

1 authorised claim · 15 capsules · ingredient page
  • “Molybdenum contributes to normal sulphur amino acid metabolism” · Metabolism

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

All 15 molybdenum capsules

Thiamine

1 authorised claim · 5 capsules · ingredient page
  • “Thiamine contributes to normal energy-yielding metabolism” · Metabolism

All 5 thiamine capsules

Phosphorus

1 authorised claim · 3 capsules · ingredient page
  • “Phosphorus contributes to normal energy-yielding metabolism” · Metabolism

Betaine

1 authorised claim · 2 capsules · ingredient page
  • “Betaine contributes to normal homocysteine metabolism” · Metabolism

Assessed by the register and not authorised

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

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