Thorne Vitamin D + K2 – Liquid Drops | Supports Bone, Immune & Cardiovascular Health, 1 fl oz (30 mL)

What Is Thorne Vitamin D + K2?

Thorne Vitamin D + K2 is a liquid drop formula combining Vitamin D3 (Cholecalciferol) and Vitamin K2 (as MK-7, Menaquinone-7) in a single, convenient liquid format housed in an amber glass dropper bottle for light protection and dosing precision. This synergistic pairing addresses one of the most important — and most clinically misunderstood — relationships in nutritional medicine: Vitamin D drives calcium absorption from the gut, but without adequate Vitamin K2, that calcium cannot be properly directed into bone and may instead deposit in arterial walls and soft tissues. Together, D3 and K2 (MK-7) ensure calcium is absorbed efficiently and deposited correctly — into bone where it belongs, and away from arteries where it causes harm. NSF Certified for Sport®.

The D3 + K2 Synergy – Why Both Matter

• Vitamin D3 (Cholecalciferol) — The most bioactive, natural form of Vitamin D (the same form produced in the skin upon UVB sun exposure). D3 activates Vitamin D receptors (VDR) throughout the body, stimulating the production of osteocalcin and matrix Gla protein (MGP) — two Vitamin K2-dependent proteins critical for bone mineralization and arterial calcium regulation. D3 also upregulates calcium absorption in the intestine by up to 30–40%, making calcium from diet and supplements far more bioavailable
• Vitamin K2 as MK-7 (Menaquinone-7) — MK-7 is the most bioavailable and longest-acting form of Vitamin K2, with a plasma half-life of 72 hours (vs. 1–2 hours for MK-4). MK-7 activates two critical proteins: Osteocalcin (which anchors calcium into the bone matrix, increasing bone mineral density) and Matrix Gla Protein / MGP (which inhibits arterial calcification by binding and removing calcium from blood vessel walls). Without K2 activation of these proteins, the increased calcium absorbed via Vitamin D has no guidance system and may deposit in the wrong tissues

Key Benefits

• Bone Density & Skeletal Health — D3 increases calcium absorption from the gut; K2 (MK-7) activates osteocalcin to incorporate that calcium into the bone matrix. Multiple clinical trials show the D3+K2 combination produces significantly greater improvements in bone mineral density than either nutrient alone, making this combination essential for osteoporosis prevention and skeletal integrity at every age
• Arterial Health & Cardiovascular Protection — K2 (MK-7) activates Matrix Gla Protein (MGP), the body’s most potent inhibitor of arterial and soft tissue calcification. Epidemiological studies (including the Rotterdam Study and Prospect Study) show that higher K2 intake is associated with significantly reduced arterial calcification, reduced cardiovascular mortality, and lower risk of coronary artery disease — independent of Vitamin D status
• Immune System Support — Vitamin D3 is one of the most critical immune-modulating nutrients known. VDRs are expressed on virtually every immune cell type. D3 enhances innate immune responses (macrophage and neutrophil activity), modulates adaptive immunity to prevent autoimmune overactivation, and upregulates the production of antimicrobial peptides (cathelicidins, defensins) that defend against viral and bacterial pathogens
• Muscle Function & Fall Prevention — Vitamin D3 receptors are present in muscle tissue. Adequate D3 is required for muscle protein synthesis, neuromuscular function, and maintenance of fast-twitch muscle fiber composition — directly reducing the risk of falls and fractures, particularly in older adults
• Mood & Mental Health — Vitamin D3 receptors are expressed throughout the brain, including in regions involved in mood regulation. Vitamin D deficiency is strongly associated with depression, seasonal affective disorder (SAD), and cognitive decline. Supplementation supports healthy mood, motivation, and neurological function
• Liquid Format — Flexible Dosing & Superior Absorption — The liquid drop format allows precise, flexible dose adjustment (per drop or per serving) to match individual needs assessed via 25-OH Vitamin D blood testing. Liquid D3 in an oil carrier is absorbed more efficiently than dry tablet or powder capsule forms, and is ideal for individuals who have difficulty swallowing capsules

Why MK-7 Over MK-4?

Most lower-cost Vitamin K2 supplements use MK-4 (synthetic menaquinone-4), which has a very short plasma half-life of 1–2 hours, requiring multiple daily doses for sustained activation of osteocalcin and MGP. Thorne uses MK-7 (natural, fermentation-derived menaquinone-7), which has a 72-hour plasma half-life, ensuring continuous activation of K2-dependent proteins throughout the day and night from a single daily dose. MK-7 is also significantly more potent per mcg than MK-4 in clinical studies of bone and cardiovascular outcomes.

Who Should Take This?

• Individuals with low sun exposure or confirmed Vitamin D deficiency (25-OH D below 30 ng/mL)
• Adults seeking to protect bone density and prevent osteoporosis and fractures
• Those supporting cardiovascular health and arterial flexibility through calcium regulation
• Individuals taking calcium supplements who need K2 to direct calcium into bone appropriately
• People seeking flexible, precise Vitamin D dosing beyond fixed-dose capsule formats
• Those who have difficulty swallowing capsules or prefer liquid supplementation
• Competitive athletes requiring NSF Certified for Sport® verified supplements

How to Use

Use the dropper to dispense the desired number of drops directly under the tongue or mix into water, juice, or a smoothie, or as directed by your healthcare practitioner. Optimal Vitamin D dosing should be personalized based on serum 25-OH Vitamin D levels measured via blood test. General maintenance dosing is typically 1,000–2,000 IU D3 per day; therapeutic repletion under practitioner guidance may require higher doses. Take with a meal containing dietary fat to maximize absorption of these fat-soluble vitamins. Store upright in a cool, dry place away from light.

Product Highlights

• Vitamin D3 (Cholecalciferol) + Vitamin K2 (MK-7) — synergistic bone & cardiovascular combination
• MK-7 form — 72-hour half-life for all-day osteocalcin and MGP activation
• Liquid drops — flexible dosing, fast absorption, ideal for capsule-averse users
• Amber glass dropper bottle — light-protected for ingredient stability
• Supports Bone Density, Arterial Health, Immune Defense & Mood
• 1 fl oz (30 mL) — multiple months’ supply depending on dose
• NSF Certified for Sport® | No unnecessary excipients
• From Thorne — trusted by healthcare practitioners worldwide