Sports Research Vitamin D3 + K2
Delivers 5000 IU vegan D3 (from lichen) and 100mcg K2 as MK-7 in a coconut-oil softgel. Evidence supports D3 for bone health when you're deficient; benefit in already-replete adults is limited (VITAL). K2 (MK-7) improves matrix Gla protein carboxylation. Not medical advice — test your levels first.
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What the research says
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“Supplementation with vitamin D did not result in a lower incidence of invasive cancer or cardiovascular events than placebo.”
In a large RCT of mostly D-replete adults, 2000 IU/day D3 did not lower invasive cancer or major cardiovascular events over ~5.3 years — evidence that routine supplementation has limited benefit when you are not deficient.
Manson JE et al., NEJM (VITAL) · 2019 ↗ -
“In conclusion, long-term use of MK-7 supplements improves arterial stiffness in healthy postmenopausal women, especially in women having a high arterial stiffness.”
Three years of 180 µg/day MK-7 improved arterial stiffness and increased carboxylation of vitamin K-dependent proteins in healthy postmenopausal women, supporting K2's role in calcium handling.
Knapen MHJ et al., Thrombosis and Haemostasis · 2015 ↗ -
“BMD decreased at all sites without differences between the MK-7 and placebo-treated women. Changes in bone turnover markers and microstructure were similar between the two groups.”
A 3-year double-blind RCT (142 postmenopausal women with osteopenia) found 375 µg/day MK-7 did NOT improve bone mineral density or microarchitecture versus placebo — a null result for bone outcomes.
Rønn SH et al., 3-year RCT (Osteoporosis Int.) · 2020 ↗
Educational summary of the research — not medical advice. Evidence strength varies and individual results differ; talk to a qualified clinician before changing your health routine.
How it compares
| D3 + K2 | D3 alone | Multivitamin | |
|---|---|---|---|
| Includes K2 (MK-7) | Yes, 100 mcg | No | Rarely / low |
| Vitamin D3 dose | 5000 IU (high) | Varies, often high | Typically 400-1000 IU |
| Vegan D3 source | Yes (lichen) | Varies | Usually not |
| Focus | Bone + calcium handling | D-status correction | Broad, low doses |
Buy it if
- People whose bloodwork confirms low vitamin D
- Vegans and vegetarians who can't use lanolin-derived D3
- Those who specifically want K2 (MK-7) alongside D3
- Anyone who prefers a third-party-tested single-softgel format
Skip it if
- People who haven't tested and may already be D-replete
- Anyone on warfarin / vitamin K-antagonist anticoagulants without clinician sign-off
- Those wanting a lower maintenance dose (1000-2000 IU)
The verdict
A genuinely well-made vegan D3 + K2 (MK-7) softgel with credible third-party testing and the better-studied K2 form. Evidence supports D3 for bone health when you're actually deficient, and K2 has plausible mechanistic backing — but the 5000 IU dose is best matched to a confirmed low level, not taken on spec. Test first. Not medical treatment.
Check price on Amazon Live price & reviews on AmazonQuestions, answered
- Should I take 5000 IU of vitamin D every day?
- Only if a blood test (25-hydroxyvitamin D) shows you're low — 5000 IU is a generous, deficiency-correcting dose. In people already replete, VITAL found little added benefit, and high long-term intakes should be discussed with a clinician. Source Manson et al., NEJM (VITAL) ↗
- Why combine D3 with K2?
- D3 raises calcium absorption; K2 (MK-7) activates proteins like matrix Gla protein that influence where calcium goes. The mechanistic/surrogate evidence for K2 is reasonable, but hard outcome proof (fewer fractures or cardiac events) is still limited. Source Knapen et al., Thromb Haemost ↗
- Is this suitable for vegans?
- Yes. The D3 is from lichen and the K2 (MK-7) from fermented chickpea, and it's Vegan Certified and Non-GMO Project Verified — unusual for D3, which is often from lanolin. Source Sports Research, Vitamin D3 + K2 product page ↗