How to choose collagen, biotin and zinc

The Skin, hair, nails category holds more collagen than anything else – in powders, drinks and capsules – with biotin, zinc and selenium next to it. Biotin, zinc and selenium have authorised EU claims on skin, hair and nails; collagen has none, so collagen is chosen by dose, source and ingredients. If hair is your main interest, read our separate article on supplements and hair; this one is about comparing labels.

Contents

1. Collagen, biotin and zinc: what they are and what may be said about them
2. How to read the label
3. Product forms: choose by convenience
4. Safety: upper levels and when to ask a doctor
5. Single nutrient or complex, ingredients and allergens
6. Collagen, biotin and zinc in the Vitateka catalogue
7. Frequently asked questions

Collagen, biotin and zinc: what they are and what may be said about them

Collagen is a protein; supplements contain hydrolysed collagen (peptides) from fish or bovine raw material. Biotin is a B vitamin (B7). Zinc and selenium are minerals.

In the EU, the benefits of vitamins and minerals may only be described in the wording of the register of authorised claims (Regulation 432/2012), for example:

• Biotin contributes to the maintenance of normal hair.
• Biotin contributes to the maintenance of normal skin.
• Zinc contributes to the maintenance of normal nails.
• Selenium contributes to the maintenance of normal hair.
• Vitamin C contributes to normal collagen formation for the normal function of skin.

These claims apply to a product whose daily portion provides at least 15 % of the nutrient reference value (NRV). For adults the NRV is 50 µg of biotin, 10 mg of zinc, 55 µg of selenium and 80 mg of vitamin C (Regulation 1169/2011, Annex XIII). There are no authorised claims for collagen, hyaluronic acid, MSM or keratin.

How to read the label

Collagen: grams per daily serving. In powders a serving holds 8–10 g of collagen: 10 g in two scoops of the VITATEKA bovine collagen powder, 8.7 g in 10 g of OstroVit "Collagen + vitamin C" powder, 8 g in VitalHarmony "Collagen + vitamin C". In liquids it is 10–12.5 g per 25 ml.

Biotin: micrograms and big percentages. The NRV for biotin is 50 µg, so 10,000 µg is 20,000 % NRV. A Golden Pharm tablet holds 2,400 µg, an OstroVit "Biotin Plus" tablet 2,500 µg, the VITATEKA liquid biotin 10,000 µg per 15 ml.

Zinc: the amount of zinc itself. An OstroVit "Biotin Plus" tablet contains 15 mg of zinc (from picolinate), the same as the separate OstroVit zinc picolinate. Taking both gives 30 mg. How to tell the weight of a salt from the mineral itself is shown in detail in our magnesium buying guide.

Price per day and price per gram. At the prices of 07.10.2026 (delivery to Estonia, VAT included): VITATEKA bovine collagen powder, 300 g – 22.90 €, 30 servings of 10 g, about 0.76 € a day; OstroVit "Collagen + vitamin C", 400 g – 17.79 €, 40 servings of 8.7 g of collagen, about 0.44 € a day; VITATEKA sugar-free marine collagen 10,000 mg, 500 ml – 24.90 €, 20 servings of 25 ml, about 1.25 € a day. Per gram of collagen that is roughly 0.08 €, 0.05 € and 0.12 €.

Product forms: choose by convenience

• Powders are stirred into water or juice; they come unflavoured and flavoured (with flavourings and sweeteners). In our examples a gram of collagen is cheapest in powder.
• Liquids are a ready serving with vitamins; once opened, store them as instructed: the VITATEKA sugar-free marine collagen 10,000 mg must be used within 2 months of opening.
• Tablets and capsules are for biotin, zinc and selenium. A capsule holds hundreds of milligrams of collagen, a serving of powder holds grams.

There are no authorised EU claims that one form is "better absorbed" – choose by convenience, taste and ingredients. In the Skin, hair, nails category you can filter straight away by powders, capsules or liquid forms.

Safety: upper levels and when to ask a doctor

The tolerable upper intake level (UL) is the highest daily intake from all sources, food included, at which EFSA does not expect harm with long-term use.

• Biotin and blood tests. High doses of biotin can distort the results of some laboratory tests – the US FDA has warned about this since 2017. Before a blood test, tell your doctor and the laboratory that you take biotin.
• Zinc in several products. "Biotin Plus" (15 mg) and a separate zinc (15 mg) make 30 mg together, which is above the upper level; choose one.
• Retinol. VITATEKA "Marine collagen Gold Retinol" contains 800 µg of vitamin A per 25 ml. During pregnancy take supplements with vitamin A only after consulting a doctor, and do not combine it with other products containing retinol.
• Vitamin D in collagen drinks. Gold Retinol also contains vitamin D3; if you take a separate D3 supplement, for example 4,000 IU (100 µg), add up the doses.
• Folic acid. An OstroVit "Biotin Plus" tablet contains 800 µg of folic acid; do not add other products with folic acid without a doctor's advice.

Ask a doctor before use if you are pregnant or breastfeeding, take medicines or are under medical supervision.

Single nutrient or complex, ingredients and allergens

Biotin or zinc on its own is easier to combine with other supplements. Complexes ("Biotin Plus" – biotin, zinc, selenium and folic acid; collagen with vitamins) are more convenient, but it is easy to double up zinc, vitamin D and vitamin A with them.

• The source of collagen. Fish (marine) in the VITATEKA sugar-free marine collagen 10,000 mg and Gold Retinol; bovine in the VITATEKA bovine collagen powder and in the OstroVit and VitalHarmony collagens. If you are allergic to fish, choose bovine.
• Sugar and sweeteners. The VITATEKA liquid biotin contains steviol glycosides and sucrose; the sugar-free marine collagen contains the sweeteners cyclamate, saccharin and stevioside; OstroVit "Collagen + vitamin C" contains sucralose; the VITATEKA bovine collagen powder contains no sugar.
• Vitamin C next to collagen. Vitamin C has an authorised claim on collagen (see above), so check how much a serving contains: 500 mg in OstroVit and VitalHarmony, 120 mg in Gold Retinol, 60 mg in the sugar-free marine collagen.
• Traces of allergens. VitalHarmony states that the product may contain milk, soy, nuts, gluten, eggs, crustaceans and fish.
• Plant extracts (grape seed extract and green tea in the sugar-free marine collagen): there are no authorised EU claims for them yet, so we only describe the ingredients.

Collagen, biotin and zinc in the Vitateka catalogue

All products below were in stock on 07.10.2026; the doses are taken from the labels on our website. More options are in the Skin, hair, nails category (with the "How to choose" and "Our pick" panel) and in the Collagens and Biotin sections.

• Collagen, powder: VITATEKA bovine collagen powder, 300 g – 10 g per serving, no sugar; OstroVit "Collagen + vitamin C", peach, 400 g – 8.7 g of collagen and 500 mg of vitamin C; VitalHarmony "Collagen + vitamin C", pear and mango, 400 g – 8 g of collagen and 500 mg of vitamin C.
• Collagen, liquid: VITATEKA sugar-free marine collagen 10,000 mg, 500 ml – 10 g per 25 ml; VITATEKA "Marine collagen Gold Retinol", 500 ml – 12.5 g of collagen, 5,000 µg of biotin, 800 µg of vitamin A and vitamin D3 per 25 ml.
• Biotin: VITATEKA liquid biotin 10,000 µg – 10,000 µg of biotin and 80 mg of vitamin C per 15 ml; Golden Pharm Biotin – 2,400 µg, 30 tablets; OstroVit "Biotin Plus" – 2,500 µg of biotin, 15 mg of zinc, 100 µg of selenium and 800 µg of folic acid, 100 tablets.
• Zinc and selenium: OstroVit zinc picolinate – 15 mg, 150 tablets; Mirrolla selenium 150 µg – 150 µg, 40 tablets.
• Hyaluronic acid: VITATEKA liquid hyaluronic acid – 100 mg of sodium hyaluronate and 80 mg of vitamin C per 15 ml.

More on the topic – our selections Zinc, Selenium, Hyaluronic acid and hair care products.

In short

• Compare collagen by grams per daily serving and by the price per gram.
• The source of collagen – fish or bovine – is stated in the ingredients; this matters if you are allergic to fish.
• Collagen, hyaluronic acid and MSM have no authorised claims; biotin, zinc, selenium and vitamin C do.
• Biotin 10,000 µg is 20,000 % NRV; before a blood test, tell your doctor that you take biotin.
• Add up zinc, vitamin D, vitamin A and folic acid from all products.
• Pregnant or breastfeeding women and people taking medicines – ask a doctor first.

Frequently asked questions

How much collagen is in one serving?

In the powders of our selection 8–10 g, in liquids 10–12.5 g per 25 ml. Capsules usually hold hundreds of milligrams, so compare grams per daily serving, not the number of capsules or tubs.

Why is vitamin C added to collagen?

Vitamin C has an authorised claim on collagen: "Vitamin C contributes to normal collagen formation for the normal function of skin". There are no such claims for collagen itself.

Marine or bovine collagen – which to choose?

They are different raw-material sources; there are no authorised claims that one of them is "better". If you are allergic to fish, choose bovine.

Isn't 10,000 µg of biotin a lot?

It is 20,000 % NRV. No upper level has been set for biotin (SCF, 2001), but high doses can distort the results of some blood tests – tell your doctor and the laboratory that you take biotin.

Can I take "Biotin Plus" and zinc at the same time?

"Biotin Plus" already contains 15 mg of zinc. With a separate zinc supplement (another 15 mg) that makes 30 mg – more than the upper level of 25 mg a day (SCF, 2002). Choose one product.

How long does liquid collagen keep after opening?

Check the label: the VITATEKA sugar-free marine collagen 10,000 mg must be used within 2 months of opening.

Important information

A food supplement is not a substitute for a varied and balanced diet and a healthy lifestyle. Do not exceed the recommended daily dose. If you are pregnant, breastfeeding, taking medicines or under medical supervision, ask a doctor before use. Keep out of the reach of children.

Read also

• VITATEKA Marine collagen Gold Retinol: ingredients
• How to choose calcium, vitamin D and collagen