Written by the Plenthera team (trained in orthomolecular nutrition). Scientifically reviewed in October 2026. Last updated: 6 October 2026.
Calcium is the most abundant mineral in the body: almost all of it is in the bones and teeth, the rest is indispensable for muscles, nerves, blood clotting and enzymes. At Plenthera you will find calcium in the Bot- en Tandformule Pro from Vitals, in which calcium bisglycinate is combined with magnesium, vitamin D3 and vitamin K2. The Elke Dag multivitamins from Vitals also contain calcium.
Which calcium suits you?
| Product | Calcium per daily dose | Features |
|---|---|---|
| Vitals Bot- en Tandformule Pro (at Plenthera) | 200 mg (2 tablets) | Bisglycinate (TRAACS®) with 100 mg magnesium, 50 µg vitamin D3, 180 µg vitamin K2 and silicon |
| Vitals Elke Dag multivitamins (at Plenthera) | 150–200 mg | Calcium from red algae (Aquamin®) in a complete multi |
| KiKi Health Ionic Electrolytes (at Plenthera) | 8 mg (30 drops) | Electrolyte drops; not a calcium supplement |
| Calcium citrate or carbonate (other forms on the market) | Variable | Individual calcium tablets — we do not currently stock these |
What is calcium?
Calcium (Ca) is an essential mineral. An adult body contains about 1 to 1.2 kilos of calcium, of which approximately 99% is in the bones and teeth. The small part outside them is needed for muscle function, signal transmission between nerve cells, blood clotting and the functioning of digestive enzymes.
The body keeps the calcium level in the blood within narrow limits. If intake is too low, calcium is released from the bones. Good food sources are dairy, green leafy vegetables such as kale, almonds, sesame, calcium-set tofu, sardines with bones and fortified plant-based drinks.
EFSA specifies a reference intake of 950 mg per day for adults aged 25 and over (18–24 years: 1,000 mg). Labels use 800 mg (RI). The safe upper limit for total intake from food and supplements is 2,500 mg per day.
Calcium and EFSA — what is scientifically recognised?
The following health claims are authorised for calcium in Regulation (EU) 432/2012:
- Calcium contributes to normal blood clotting.
- Calcium contributes to normal energy-yielding metabolism.
- Calcium contributes to normal muscle function.
- Calcium contributes to normal neurotransmission.
- Calcium contributes to the normal function of digestive enzymes.
- Calcium has a role in the process of cell division and specialisation.
- Calcium is needed for the maintenance of normal bones.
- Calcium is needed for the maintenance of normal teeth.
The claims apply with a daily intake that provides at least 15% of the reference intake: 120 mg calcium per daily dose. The Bot- en Tandformule Pro and the Elke Dag multivitamins reach this threshold; the electrolyte drops do not.
Calcium, vitamin D and vitamin K
Calcium is often combined with vitamin D, vitamin K and magnesium. There are authorised claims for this:
- Vitamin D contributes to normal absorption/utilisation of calcium and phosphorus.
- Vitamin K contributes to the maintenance of normal bones.
- Magnesium contributes to the maintenance of normal bones.
Vitamin K2 is needed for the activation of osteocalcin, a protein in bone that binds calcium; this mechanism is widely researched. Read more about the individual vitamins at vitamin D and vitamin K.
Calcium at Plenthera and other forms on the market
Bot- en Tandformule Pro (Vitals) — at Plenthera
Per 2 tablets: 200 mg calcium and 100 mg magnesium, both as bisglycinate (TRAACS®), 6 mg silicon (MESOPOROSIL®), 50 µg vitamin D3 and 180 µg vitamin K2 (menaquinone-7). Because of the vitamin D dosage not suitable for children aged 10 and under; because of the vitamin K not suitable when using coumarin-type anticoagulants (acenocoumarol, phenprocoumon).
Calcium in multivitamins — at Plenthera
The Elke Dag multivitamins from Vitals contain 150–200 mg calcium from red algae (Aquamin®), alongside magnesium, vitamin D3 and K2.
Other forms on the market
Calcium carbonate contains a lot of calcium per gram (about 40%) and is best taken with a meal. Calcium citrate (about 21%) is less dependent on stomach acid. There is also standalone calcium from red algae and microcrystalline hydroxyapatite. We do not currently stock these as separate products.
How do you use calcium?
- First check how much calcium you get from food; a supplement tops up.
- Follow the dosage on the label and include calcium from multivitamins in your count.
- Take calcium with a meal, preferably no more than 500 mg at a time.
- Keep 2 hours apart from iron, thyroid medication (levothyroxine) and tetracycline or quinolone antibiotics.
- With kidney stones, kidney conditions or an elevated calcium level in the blood: consult your doctor first.
Myths and misconceptions about calcium
Myth 1: "Dairy is the only good source of calcium."
Incorrect. Green leafy vegetables, almonds, sesame, calcium-set tofu, sardines with bones and fortified plant-based drinks also provide calcium.
Myth 2: "The more calcium, the better."
Incorrect. Above your requirement, extra calcium provides no demonstrated benefit, and total intake should remain below the upper limit of 2,500 mg per day. Research on high-dose calcium supplements and the heart and blood vessels is not conclusive.
Myth 3: "Calcium alone is enough for strong bones."
Bones need more than calcium: protein, vitamin D, vitamin K, magnesium and exercise also play a role.
Combining calcium with other supplements
- Vitamin D: contributes to normal absorption/utilisation of calcium and phosphorus.
- Vitamin K: contributes to the maintenance of normal bones.
- Magnesium: contributes to the maintenance of normal bones and teeth.
- Multivitamins: include the calcium from these in your total intake.
- Strong bones: all products around the bone theme together.
Frequently asked questions
How much calcium do I need per day?
EFSA specifies a reference intake of 950 mg per day for adults aged 25 and over (18–24 years: 1,000 mg). Labels use 800 mg. The safe upper limit for total intake is 2,500 mg per day.
Do I get enough calcium from my diet?
Those who eat dairy daily often already get most of their requirement from food. Other sources are green leafy vegetables, almonds, sesame, calcium-set tofu and fortified plant-based drinks. A supplement is a supplement, not a replacement.
Why is calcium often combined with vitamin D and K?
Vitamin D contributes to normal absorption/utilisation of calcium and phosphorus, and vitamin K contributes to the maintenance of normal bones. That is why many bone formulas, such as the Vitals Bot- en Tandformule Pro, combine these substances.
What is the difference between calcium bisglycinate, citrate and carbonate?
Carbonate contains a lot of calcium per gram and is best taken with a meal. Citrate and bisglycinate contain less calcium per gram and are less dependent on stomach acid. At Plenthera we stock calcium as bisglycinate.
When should I take calcium?
With a meal and preferably no more than 500 mg at a time. Keep 2 hours apart from iron, thyroid medication and certain antibiotics.
Is calcium safe as a supplement?
Yes, within the label dosage and below the upper limit of 2,500 mg per day together with your diet. Research on high-dose calcium supplements and the heart and blood vessels is not conclusive; that is why calcium from food is the basis. With kidney stones or kidney conditions: consult your doctor.
Sources
- Regulation (EU) 432/2012 — authorised health claims for calcium, vitamin D and vitamin K.
- EFSA NDA Panel (2015). Scientific Opinion on Dietary Reference Values for calcium. EFSA Journal 13(5):4101.
- EFSA NDA Panel (2012). Scientific Opinion on the Tolerable Upper Intake Level of calcium. EFSA Journal 10(7):2814.
- Straub DA (2007). Calcium supplementation in clinical practice: a review of forms, doses, and indications. Nutr Clin Pract 22(3):286–296.
- Bolland MJ et al. (2010). Effect of calcium supplements on risk of myocardial infarction and cardiovascular events: meta-analysis. BMJ 341:c3691.
Disclaimer: This text is for informational purposes only and does not replace medical advice. Calcium is a food supplement, not a medicine. If in doubt or if you take medication, we recommend consulting a doctor or orthomolecular therapist first.