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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.

Thyroid and Bones and Immunity and Blood and iron

1418 capsules across 56 ingredients

Thyroid. Only iodine and selenium hold authorised register wording about the thyroid, quoted exactly on their pages. Thyroid conditions are diagnosed and managed by a GP, and the British Thyroid Foundation is the specialist charity.

Bones. Ingredients here hold register claims relating to the maintenance of normal bones, quoted exactly on their pages. Weight-bearing exercise and dietary calcium are the foundations, and the Royal Osteoporosis Society is the specialist charity for anything further.

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.

Blood and iron. Ingredients here hold register wording about normal red blood cell formation, oxygen transport, iron absorption or normal blood clotting, quoted exactly on their pages. Suspected iron deficiency needs a blood test before a supplement; the NHS page below explains why.

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 the maintenance of normal bones” · Bones

Not authorised for immunity or blood and iron: the register refused 2 claims there.

All 334 magnesium capsules

Vitamin C

4 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 collagen formation for the normal function of bones” · Bones
  • “Vitamin C increases iron absorption” · Blood and iron

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 bones” · Bones

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

All 249 zinc capsules

Vitamin D

5 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
  • “Vitamin D contributes to the maintenance of normal bones” · Bones
  • “Vitamin D is needed for normal growth and development of bone in children.” · Bones
  • and 1 more on the ingredient page

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

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 normal red blood cell formation” · Blood and iron

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

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 normal red blood cell formation” · Blood and iron

Not authorised for bones: 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 normal blood formation” · Blood and iron

All 138 folate capsules

Vitamin K

2 authorised claims · 106 capsules · ingredient page
  • “Vitamin K contributes to the maintenance of normal bones” · Bones
  • “Vitamin K contributes to normal blood clotting” · Blood and iron

All 106 vitamin k capsules

Calcium

4 authorised claims · 96 capsules · ingredient page
  • “Calcium helps to reduce the loss of bone mineral in post-menopausal women. Low bone mineral density is a risk factor for osteoporotic bone fractures” · Bones
  • “Calcium is needed for normal growth and development of bone in children.” · Bones
  • “Calcium is needed for the maintenance of normal bones” · Bones
  • “Calcium contributes to normal blood clotting” · Blood and iron

All 96 calcium capsules

Selenium

2 authorised claims · 95 capsules · ingredient page
  • “Selenium contributes to the normal function of the immune system” · Immunity
  • “Selenium contributes to the normal thyroid function” · Thyroid

All 95 selenium capsules

Iron

3 authorised claims · 87 capsules · ingredient page
  • “Iron contributes to the normal function of the immune system” · Immunity
  • “Iron contributes to normal formation of red blood cells and haemoglobin” · Blood and iron
  • “Iron contributes to normal oxygen transport in the body” · Blood and iron

All 87 iron capsules

Copper

2 authorised claims · 58 capsules · ingredient page
  • “Copper contributes to the normal function of the immune system” · Immunity
  • “Copper contributes to normal iron transport in the body” · Blood and iron

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 bones: the register refused 2 claims there.

All 54 vitamin a capsules

Iodine

1 authorised claim · 45 capsules · ingredient page
  • “Iodine contributes to the normal production of thyroid hormones and normal thyroid function” · Thyroid

All 45 iodine capsules

Riboflavin

1 authorised claim · 36 capsules · ingredient page
  • “Riboflavin contributes to the maintenance of normal red blood cells” · Blood and iron

All 36 riboflavin capsules

Manganese

1 authorised claim · 32 capsules · ingredient page
  • “Manganese contributes to the maintenance of normal bones” · Bones

All 32 manganese capsules

Phosphorus

2 authorised claims · 3 capsules · ingredient page
  • “Phosphorus contributes to the maintenance of normal bones” · Bones
  • “Phosphorus is needed for the normal growth and development of bone in children” · Bones

Protein

2 authorised claims · 1 capsule · ingredient page
  • “Protein contributes to the maintenance of normal bones” · Bones
  • “Protein is needed for normal growth and development of bone in children.” · Bones

Assessed by the register and not authorised

The register looked at claims for these relating to thyroid and bones and immunity and blood and iron 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

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