Nature Made D3 5000 IU
Nature Made D3 5000 IU
Price: $13.01 | Rating: 4.8/5 (67,777 reviews) | Dose: 5000 IU | Servings: 180
4 Best Vitamin D3 + K2 Supplements in 2026
Vitamin D deficiency is one of the most common nutrient deficiencies in the United States. The NIH Office of Dietary Supplements reports that approximately 35% of adults in the US have blood levels below 20 ng/mL — the threshold for deficiency. Vitamin D3 supplementation is the standard treatment, but D3 alone is only half the equation. Without vitamin K2, the calcium that D3 helps absorb can end up in your arteries instead of your bones.
This guide covers four products: a standalone D3, a vegan D3, a combined D3+K2, and a standalone K2. Together they represent the best options for bone density, immune function, and cardiovascular health — the three systems that D3+K2 together support.
1. Nature Made D3 5000 IU
Nature Made's D3 5000 IU is a popular vitamin D supplement on Amazon, and the 67,777 reviews make it one of the most-reviewed supplements of any kind. The 5000 IU dose is appropriate for adults who need to raise or maintain blood levels — most people need 2,000-5,000 IU/day to stay above 30 ng/mL.
The softgel form uses soybean oil as the carrier — vitamin D is fat-soluble, so it needs a fat source for absorption. Take it with a meal containing fat for best results. The 180-count bottle is a 6-month supply at 1/day. At $13.01, that's $0.07/day — cheaper than almost any other supplement. USP verification means the label claim is independently confirmed.
2. NATURELO Vegan D3 5000 IU
NATURELO Vegan D3 5000 IU
NATURELO Vitamin D3 is sourced from lichen — a plant-based cholecalciferol identical to the D3 produced by human skin. Vegan capsules, non-GMO, gluten-free. 5000 IU per capsule.
Price: ~$15-18 | Rating: 4.6/5 | Dose: 5000 IU | Source: Lichen (vegan)
Most vitamin D3 supplements are derived from lanolin (sheep's wool grease). NATURELO's D3 is derived from lichen — a symbiotic organism of fungi and algae that produces cholecalciferol naturally. This is the same D3 molecule that human skin produces from sunlight — identical in structure and function to the lanolin-derived form, but suitable for vegans.
The lichen source matters because D2 (ergocalciferol, the plant-derived form) is significantly less effective at raising blood levels than D3. Until lichen-derived D3 became available, vegans were stuck with D2. Now they can get the superior D3 form from a plant source.
3. NATURELO Vitamin D3 + K2, Vegan — Best Combo
NATURELO Vegan D3+K2
NATURELO D3+K2 combines plant-based D3 from lichen with vegan K2 (MK-7) in one capsule. Directs calcium to bones and away from arteries. 60 vegan capsules.
Price: ~$18-22 | Rating: 4.5/5 | Dose: D3 + K2 combo | Servings: 60
If you want the convenience of D3 and K2 in a single capsule, NATURELO's combo is the best vegan option. The D3 comes from lichen (same as their standalone) and the K2 is MK-7 from fermentation. One capsule per day provides both nutrients in clinically appropriate doses.
The rationale for combining them: D3 increases calcium absorption from the gut. But once calcium is in the blood, D3 doesn't control where it goes. K2 activates matrix Gla protein (MGP), which binds calcium in blood vessels and prevents arterial calcification. K2 also activates osteocalcin, which directs calcium into bone mineral. Without K2, high-dose D3 supplementation may contribute to arterial calcification — the opposite of what you want.
4. NOW MK-7 Vitamin K-2 100mcg — Best Standalone K2
NOW Vitamin K2 MK-7
NOW MK-7 Vitamin K-2 provides 100mcg of menaquinone-7 — the long-acting K2 form that stays in blood for 72+ hours. Supports bone mineralization and arterial health. 120 veg capsules.
Price: $20.35 | Rating: 4.7/5 (8,758 reviews) | Form: MK-7 | Servings: 120
For those already taking a standalone D3 (like the Nature Made above) who want to add K2 separately, NOW's MK-7 is the best standalone option. The 100mcg dose matches the dose used in clinical trials showing improved bone mineral density and reduced arterial calcification.
MK-7 is superior to MK-4 for supplementation because of its long half-life. MK-4 clears from blood in about 8 hours, requiring 2-3 doses per day. MK-7 persists for 72+ hours, meaning once-daily dosing maintains therapeutic blood levels. NOW's product is soy-derived (via fermentation), vegetarian, and kosher. The 120-capsule bottle is a 4-month supply.
D3 + K2: The Science
The interaction between D3 and K2 centers on calcium metabolism. Vitamin D3 increases intestinal calcium absorption by upregulating the TRPV6 calcium channel. Without adequate K2, this additional calcium has no specific direction - it can deposit in soft tissues, including arterial walls. The Rotterdam Study, a large epidemiological cohort, found that high K2 intake was associated with significantly less arterial calcification and lower cardiovascular mortality. For immune support, D3 also plays a role - see our immune support supplements guide.
FAQ
Should I take vitamin D3 with K2?
Yes. D3 increases calcium absorption, K2 directs it to bones. Without K2, excess calcium can deposit in arteries. Think of D3 as the faucet and K2 as the pipe.
What is the difference between D3 and D2?
D3 (cholecalciferol) is the human skin-synthesized form. D2 (ergocalciferol) is plant-derived. D3 raises blood 25(OH)D levels 87% more effectively. Always choose D3.
How much vitamin D3 should I take daily?
The NIH RDA is 600-800 IU, but most experts recommend 2,000-5,000 IU/day. Get a 25(OH)D blood test to determine your personal dose. Do not exceed 10,000 IU/day without supervision.
What is MK-7 vitamin K2?
MK-7 (menaquinone-7) is the long-acting K2 form with a 72-hour half-life. One daily dose maintains therapeutic blood levels. MK-4 requires multiple daily doses. MK-7 is preferred for supplementation.