Last updated: May 2026
Quick Verdict: Sports Research Vitamin D3 + K2 is our top pick for vitamin D supplementation after 40. It combines 5,000 IU of plant-based D3 from lichen with 100mcg of K2 (MK-7) from chickpeas, all in a vegan PlantGel capsule with coconut MCT oil for optimal absorption. At about $0.25/day, it’s hard to find a better combination of quality, transparency, and value.
In this Sports Research Vitamin D3 K2 review, I’ll explain why this supplement earned the #1 spot in our Best Vitamin D Supplements guide. It’s the most popular D3+K2 supplement on Amazon, one of the top-selling supplements overall in 2026, and a favorite among both consumers and health professionals.
But popularity doesn’t always mean quality. Let’s dig into what makes this product stand out — and where it could improve.
What Is Sports Research Vitamin D3 + K2?
Sports Research D3 + K2 is a once-daily softgel that delivers two essential fat-soluble vitamins in one capsule, combined with coconut MCT oil for enhanced absorption.
Here’s a quick breakdown:
- Vitamin D3: 5,000 IU (125mcg) from lichen (VegaDELight)
- Vitamin K2: 100mcg as MK-7 from fermented chickpeas (MenaQ7)
- Carrier oil: Coconut MCT oil
- Capsule type: PlantGel (tapioca-based, vegan)
- Servings per bottle: 60 (2-month supply)
- Price: Around $15-18 per bottle (~$0.25-0.30/day)
- Certifications: Non-GMO Project Verified, Vegan Certified, cGMP facility, third-party tested
Why D3 + K2 Together?
This is one of the most important things to understand about vitamin D supplementation. Taking D3 alone increases your calcium absorption — that’s the whole point. But without K2, that extra calcium can end up in your arteries and soft tissues instead of your bones.
Vitamin K2 (specifically the MK-7 form) activates proteins that direct calcium into your bones and teeth while keeping it out of your blood vessels. Think of D3 as opening the door for calcium, and K2 as the guide that sends it to the right destination.
This is why standalone D3 supplements are increasingly being replaced by D3+K2 combinations — especially for adults over 40 who need to be mindful of both bone density and cardiovascular health.
What I Like About Sports Research D3 + K2
Plant-based D3 from lichen. Most vitamin D3 on the market comes from lanolin (sheep’s wool). Sports Research uses VegaDELight, a vegan D3 sourced from lichen. This makes it suitable for vegans and anyone who prefers plant-based supplements — without sacrificing the effectiveness of D3 over D2.
MenaQ7 K2. They don’t just use any K2 — they use MenaQ7, a branded and clinically studied form of MK-7 derived from fermented chickpeas. MenaQ7 has been used in multiple studies demonstrating its effectiveness for bone and cardiovascular health.
Coconut MCT oil for absorption. Vitamin D is fat-soluble, meaning it needs fat for proper absorption. Sports Research includes coconut MCT oil right in the softgel, so you get built-in absorption support even if you take it with a light meal.
PlantGel capsule. Their proprietary tapioca-based capsule is one of the few vegan softgels that can pass Non-GMO Project Verification. No gelatin, no carrageenan — just clean plant-based material.
Impressive certifications. Non-GMO Project Verified, Vegan Certified, made in a cGMP facility, and third-party tested. This is a level of verification that many competitors — even more expensive ones — don’t offer.
Easy to take. The softgels are small, easy to swallow, and have no taste or aftertaste. One per day is all you need.
Great value. At around $0.25/day for a D3+K2 combo with premium sourcing and multiple certifications, the value is excellent. You’d pay $0.40-0.60/day for comparable quality from premium brands.
What Could Be Better
5,000 IU may be too much for some. If your vitamin D levels are already adequate (above 30 ng/mL), 5,000 IU daily could push you higher than necessary. Sports Research does offer a 2,500 IU version for those who need a lower dose.
Turmeric in the capsule shell. In 2022, Sports Research added turmeric powder to the outer shell to protect against UV degradation. While this is a smart preservation choice, some users have reported that the new orange-colored capsules look different from the original white ones. The active ingredients haven’t changed.
No subscription option on Amazon. While you can Subscribe & Save on Amazon, the discount is smaller than buying directly from the Sports Research website or from Costco (where you can get a 160-count bottle at a better per-unit price).
Only 60 capsules per standard bottle. A 2-month supply is fine, but a 90 or 120-count option at a slightly better per-unit price would be welcome. The Costco 160-count version partially addresses this.
How to Take It
Dosage: 1 softgel daily. This gives you 5,000 IU of D3 and 100mcg of K2.
Timing: Take it with any meal, preferably the one that contains the most fat. The built-in MCT oil helps, but taking it with dietary fat maximizes absorption.
Testing: If you haven’t checked your vitamin D levels before, get a 25(OH)D blood test. This tells you exactly where you stand and helps you determine if 5,000 IU is the right dose for you. If your levels are above 50 ng/mL, you may want to switch to the 2,500 IU version or take the 5,000 IU every other day.
Consistency: Take it daily. Vitamin D builds up in your system over weeks, so sporadic use won’t give you the full benefits.
Who Should Take Sports Research D3 + K2?
Great for:
- Adults over 40 who spend most of their time indoors
- Anyone with confirmed or suspected vitamin D deficiency
- People wanting bone and cardiovascular support in one capsule
- Vegans who need a plant-based D3 source
- Anyone taking calcium supplements (K2 ensures proper calcium distribution)
Not ideal for:
- People who already have adequate vitamin D levels (get tested first)
- Those who prefer a lower dose (consider the 2,500 IU version)
- People on blood thinners like Warfarin (K2 affects blood clotting — consult your doctor)
- Anyone looking for the absolute cheapest option (generic D3 is cheaper, though lower quality)
How It Compares to Alternatives
vs. NOW Foods Vitamin D3 2,000 IU: NOW is cheaper ($0.05/day) but doesn’t include K2 or MCT oil. If budget is your top priority and you’re getting K2 elsewhere, NOW is solid. But for a complete solution, Sports Research wins.
vs. Transparent Labs D3 + K2: Very similar formula — both use 5,000 IU D3 + 100mcg K2. Transparent Labs costs more ($0.42/day) and is only available through their website. Sports Research offers better value and wider availability.
vs. NatureWise D3 5,000 IU: NatureWise is one of the best budget options at $0.05/day for a full year supply. But it doesn’t include K2. If you supplement K2 separately, the total cost ends up similar to Sports Research — with less convenience.
vs. Life Extension D and K: Life Extension includes multiple forms of K2 (MK-4 and MK-7) at a higher K2 dose. It’s a good option for those specifically focused on longevity, but costs more and uses gelatin capsules (not vegan).
The Bottom Line
Sports Research Vitamin D3 + K2 earns its position as the best overall vitamin D supplement for adults over 40. The combination of plant-based D3, clinically studied K2, coconut MCT oil for absorption, and a verified clean formula makes it a complete package.
At around $0.25/day, you’re getting a premium product at a mid-range price. The only reason to consider alternatives is if you need a lower dose, want the absolute cheapest option, or are on blood thinners.
Our rating: 4.7/5
It loses a fraction of a point for the 5,000 IU dose potentially being too high for some users without testing, and the standard bottle being only 60 count. Otherwise, it’s essentially the gold standard for D3+K2 supplementation.
→ Read our full guide: Best Vitamin D Supplements for Adults Over 40
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This content is for informational purposes only and is not medical advice. Always consult with your healthcare provider before starting any new supplement regimen.