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Contributes to:

  • Normal absorption and utilisation of calcium and phosphorus
  • Normal blood calcium levels
  • The maintenance of normal bones, normal muscle function and normal teeth
  • Normal function of the immune system
  • The process of cell division
  • Normal blood clotting

Product Information

Isotonix Vitamin D3 with K2

Isotonix Vitamin D3 with K2 contains vitamin D3, the metabolically active form of Vitamin D, along with Vitamin K2, which supports normal blood clotting and bone health. Isotonix Vitamin D3 with K2 is the first of its kind to combine both of these powerful vitamins with isotonic delivery, helping to maintain normal bones, muscle function and teeth. In addition, these vitamins work together to maintain the body’s normal absorption of calcium and phosphorus, as well as contribute to the normal function of the immune system, and the process of cell division.

Vitamins D3 and K2 are paired together in Isotonix Vitamin D3 with K2, because they work synergistically to support normal bone health. Two of the more common forms of vitamin K are K1 and K2. While there are many similarities between these two forms of vitamin K, they can be distinguished by their important differences, the most significant being their differing pharmacokinetic properties. Vitamin K1 disappears rapidly from the blood, while vitamin K2 persists in the blood’s circulation for a longer time.


Did you know that more than one billion people worldwide do not consume adequate amounts of vitamin D? This vitamin is obtained in three ways: dietary intake, sunlight or supplementation. This is why choosing the right Vitamin D supplement is essential. Despite the fact that there are many vitamin D supplements to choose from, Isotonix Vitamin D3 with K2 proves that all supplements are not created equal. By being the first of its kind to combine vitamin D with vitamin K2 in an isotonic form, this product supports the maintenance of normal bones and normal blood calcium levels. Our product contains Vitamin D3, a metabolically bioavailable form of vitamin D easily utilised by the body. Also, by enhancing vitamin D’s role in bone health and immune support, the addition of vitamin K also helps to support normal calcium absorption and vitamin K2 is the active form of vitamin K with highest bioavailability.

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Vitamin D3 (Cholecalciferol)
Vitamin D is a fat-soluble vitamin that occurs naturally in some foods like fish and eggs and is present in fortified foods such as milk and orange juice. Vitamin D is also produced by the body when sunlight strikes the skin, activating Vitamin D synthesis. Vitamin D promotes the efficient absorption of calcium and promotes the normal formation, growth and remodelling of bone.

Vitamin D deficiency can be caused by factors such as lack of exposure to sunlight, reduced skin synthesis of vitamin D, lower dietary intake, impaired intestinal absorption and reduced metabolism to active forms of Vitamin D. Factors contributing to Vitamin D deficiency increase with age. Deficiency has been linked to numerous health concerns; insufficient levels of this vitamin are associated with frail bones and muscle weakness.

Vitamin K2
Vitamin K is a fat-soluble vitamin found in meat, eggs, dairy and natto. Although it is a fat-soluble vitamin, the body stores very little vitamin K at any given time and without regular dietary intake the body’s store of Vitamin K can be rapidly depleted. Natural vitamin K2, also known as menaquinone-7 (MK-7), appears to be more bioavailable and has a longer half-life in the blood than vitamin K1. The Japanese soy-based food natto is particularly rich in menaquinone-7 (MK-7). Studies of natto consumption in Japan have linked menaquinone-7 to bone and cardiovascular health.


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Why are vitamins K and D included in Isotonix Vitamin D3 with K2?
Vitamins K and D work together to support the maintenance of normal bones. Vitamin D also contributes to the maintenance of normal muscle function and normal functioning of the immune system.
Is Isotonix Vitamin D3 with K2 safe for people on anti-coagulant medications?
Some studies have suggested that vitamin K2 does not interfere with anticoagulant medications. However, most products containing vitamin K (including K1 and/or K2) warn users taking anticoagulants not to use the product. If you are currently taking warfarin or another anticoagulant medication, you should consult your physician before taking any product containing vitamin K1 or K2.
How do I take Isotonix Vitamin D3 with K2?
Pour 1 level bottle capful of powder into the overcap. Add water to the line on the overcap (2 fl. oz./60 ml) and stir. Take once daily or as directed by your healthcare provider.  Maximum absorption occurs when taken with a meal. This product is isotonic only if the specified amounts of powder and water are used.
Is it safe to take more than 1 serving of this product daily?
One serving daily of Isotonix Vitamin D3 with K2 is recommended. Check with your healthcare provider before taking additional daily servings of this product.
Is there a toxicity level for vitamin D?
The recommended daily tolerable upper intake limit for vitamin D is 2,000 IU. If you wish to take more than one daily serving of this product, you should check with your physician.
What are dietary sources of vitamin D?
Foods naturally rich in Vitamin D include cod liver oil, salmon, mackerel, tuna and eggs.