Advertising Sponsored by Live Conscious, the makers of K2+D3 & Essential Elements, the Makers of Bone Boost
Why Everyone Needs Vitamin D3
Learn why D3 supplements are booming in popularity and why it needs to be paired with K2 for stronger bones, a healthier heart, and total-body wellness.
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Vitamin D3 is one of the most widely recommended supplements, it plays a vital role in bone density, immune health, and overall well-being. But here’s what most people (and many supplement brands) overlook: D3 works best with vitamin K2.
So how can you be sure your D3 is actually doing its job?
Without K2, D3 can send calcium into your bloodstream but not into your bones, where many need the extra support. That’s why pairing D3 with the right form of K2 is essential for bone support and heart health.
In this guide, we’ll show you why this combo matters, how to spot a truly effective K2+D3 formula, and the top 5 supplements that actually deliver on their promise.
Benefits Of Vitamins D3 and K2
Promotes Bone Health & Calcium Absorption
Helps Maintain Comfortable & Flexible Joints
Encourages Healthy Heart & Blood Circulation
Promotes Dental Health
Supports a Healthy Immune System
Aids in A Positive Mood
Energy Support
Why is vitamin D3 so important?
Vitamin D3 is a nutrient your body needs but can’t always make enough of on its own, especially if you get limited sun exposure. Maintaining healthy levels of vitamin D3 supports strong bones, a resilient immune system, and overall vitality.
But here’s the catch: to get the most out of D3, your body also needs vitamin K2. Together, they help guide calcium into your bones and keep it away from arteries, supporting both skeletal and cardiovascular health.
D3 + K2 have a dynamic relationship - working to aid calcium absorption, while directing it to your bones and teeth.
Getting to Know K2+D3
Synergistic Relationship
Vitamins K2 and D3 are a powerful duo for teeth and bone health. D3 helps your body metabolize calcium by directing it to your teeth and bones, but this job isn’t complete without K2. Vitamin K2 activates the special proteins needed to deposit calcium in the correct spots.
Combat Common Deficiencies
In a survey from the National Health and Nutrition Examination, 25% of Americans were found to be at risk of a vitamin D deficiency, while 8% were vitamin D deficient - an increase from the previous 20 years. This research shows how widespread low vitamin D levels can be, and when left untreated, vitamin D deficiency can impact bone health, as well as mood and energy levels.
Healthy Blood Flow
Some of the calcium we consume can end up being stored in blood vessels and soft tissues, constricting the flow of blood to your heart. Vitamin K2 works to draw this excess calcium away from the soft tissue, aiding in blood circulation.
Widespread Support
In addition to bone health, Vitamin D3 aids our bodies, maintaining healthy immune system responses, aiding in mood support, and supporting healthy energy levels.
Clinically Studied Ingredients
Through clinical trials, Menaquinone or MK-7, the long-chain form of vitamin K2, was found to be 10 to 100 times more powerful than generic vitamin K2, making MK7 a must for potent artery and bone support.
The Right Dose
We recommend a supplement that features a minimum of 10-20 mcg of vitamin D3 and 120 mg of vitamin K2 daily for adults, a recommendation that is also supported by the National Institute of Health.
Key Ingredients For Your Vitamin D3 Supplement
Vitamin D3
Vitamin D3 is essential for healthy bone formation, since it helps with calcium absorption. In fact, evidence suggests that taking both vitamins together is more beneficial than taking either one alone!
Vitamin K2 (MK-7)
Research has shown that the long-chain form of vitamin K2, called menaquinone-7, offers more advanced benefits than its short-chain form, menaquinone-4. Unlike MK-4, MK-7 allows for smaller, more convenient doses because it accumulates in the bloodstream. MK-7 also aids in bone mineral density, helping with bone quality and strength - making it the superior form of K2.
Avocado Oil
As a fat-soluble vitamin, vitamin K2 is easier for your body to absorb when taken with a fatty oil. Avocado oil is naturally rich in heart-friendly fat, contains a variety of healthy antioxidants, and helps preserve vitamin K2 over time.
MCT Oil
This extract of heart-healthy fats helps magnify the bioavailability of vitamins K2 and D3. When a K2 supplement with D3 combines MCT and avocado oil, it supports healthy immune, cardiovascular, and bone systems.
Which Form Comes Out on Top?
What To Avoid
Low-Quality D3
Watch out for D3 supplements that use low-quality or unlabeled sources of vitamin D3. Many budget formulas rely on synthetic or poorly absorbed forms that may not deliver the full benefits—and can even lead to imbalances when taken long-term without the right cofactors like K2.
Relying Solely on Amazon Reviews
Millions of Americans look to Amazon reviews before purchasing their products, but most don’t realize that up to 60% of reviews are paid for, making them untrustworthy.
Top 5 Vitamin D3 Supplements of 2025
The results are in! After analyzing dozens of top-selling D3 supplements across multiple metrics, we’ve narrowed our list down to the best of the best. Check out which products made it into our Top 5 and who we crowned the best of 2025.
First, here's a side-by-side comparison of how industry-leading K2+D3 supplements stack up against each other.
1. K2+D3
Owned by the Smarter Reviews Group of Companies
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Total Ranking
9.7/10
A+
Overall Grade
PROS
- Contains vitamin D3
Clinically studied MenaQ7- Avocado oil for better absorption
- 365-day money-back guarantee
CONS
- Only available in the US and Canada
The Bottom Line
K2+D3 from Live Conscious contains 125 mcg of vitamin D3 for enhanced heart and bone health benefits.
It is also formulated with MenaQ7, the only clinically supported, patented vitamin K2 on the market today.
K2+D3 also uses organic avocado oil to ensure effective absorption.
It's important to note that Live Conscious offers a comprehensive 365-day return policy, and also promotes a whole-body approach to health.
With all this in mind, K2+D3 earned its spot at the top of our list.
*Results are based on the Smarter Reviews Ranking System and do not necessarily reflect typical results from the use of these products. Please visit product websites for more information.
Learn More2. Bone boost
Owned by the Smarter Reviews Group of Companies
Total Ranking
9.5/10
A
Overall Grade
PROS
- 50mcg vitamin D3
- Veldt grape for added bone support
- Highly bioavailable form of calcium
- 365-day money-back guarantee
CONS
- Does not use clinically studied K2
- Only available online
The Bottom Line
Coming in a close second is Bone boost by Essential Elements for its competitive formula.
Bone boost contains 50 mcg of vitamin D3 and 100 mcg of vitamin K2. While it doesn't use a clinically studied form of vitamin K2, Bone boost makes up for it with the addition of ingredients, Cissus quadrangularis and Calcium Hydroxyapatite.
Cissus quadrangularis, commonly known as veldt grape, has been shown to help reduce bone loss and aid in bone formation. Calcium Hydroxyapatite is a highly bioavailable form of calcium derived from bovine, and which includes another important bone mineral, phosphorous.
Essential Elements offers a solid, 365-day money-back guarantee.
*Results are based on the Smarter Reviews Ranking System and do not necessarily reflect typical results from the use of these products. Please visit product websites for more information.
Learn More3. D3 & K2 Vitamin
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Total Ranking
8.9/10
B+
Overall Grade
PROS
- 250 mg of Vitamin D3
- 100 mcg Vitamin K2
- No harmful additives or fillers
CONS
- Lacks absorption-boosting fats
- 30-day return policy
The Bottom Line
Dr. Berg's D3 & K2 Vitamins score high on our list, thanks to the brand's dedicated focus on all-natural and keto-friendly solutions.
To boot, their formulation offers a robust dosage of 250 mg of Vitamin D3 & 100 mcg of Vitamin K2.
However, its 30-day money-back guarantee didn't do it any favors. Some won't see major results in their bone and cardiovascular health within that time frame. To make sure you're fully satisfied with your purchase, a money-back guarantee of at least 90 days is best.
Still, this is a strong overall supplement. It contains proper dosages of high-quality ingredients and lacks artificial fillers.
*Results are based on the Smarter Reviews Ranking System and do not necessarily reflect typical results from the use of these products. Please visit product websites for more information.
4. Vitamin K2+D3
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Total Ranking
8.7/10
B
Overall Grade
PROS
- 125 mcg vitamin D3
- Non-GMO
- Robust return policy
CONS
- Does not use clinically studied K2
- Magnesium stearate
- Not 3rd Party Tested
The Bottom Line
Coming in at number 4 on our list is Vitamin D3+K2 by Bronson. We were impressed by its robust dose of 125 mcg of Vitamin D3 and 90 mcg of Vitamin K2.
But there is some confusion over which type of Vitamin K they use in their formulation, which could potentially affect its efficiency.
Additionally, iffy fillers like magnesium stearate are listed as ingredients. This gave us pause, as otherwise the brand rightly deserves praise for offering products that are lab tested, non-GMO, and gluten- & soy-free.
Despite those minor disappointments, their 365-day return policy is one of the best, and helped them secure a spot on our list.
*Results are based on the Smarter Reviews Ranking System and do not necessarily reflect typical results from the use of these products. Please visit product websites for more information.
Learn More5. Vitamin D-3 & K-2
Total Ranking
7.9/10
C+
Overall Grade
PROS
- 25mcg of vitamin D3
- Low price point
CONS
- Made with weaker form of vitamin K2 (MK-4)
- Lacks absorption-boosting fats
- 30-day return policy
The Bottom Line
Vitamin D-3 & K-2 by NOW Foods ranked in our top five list because it contains key ingredients like vitamin D3 and is ideal for shoppers on a budget.
However, that's about where the benefits end. Unlike the others on our list, which use MK-7, this product uses an inferior form of vitamin K2 known as MK-4. While it promotes healthy bones, MK-4 is less potent than MK-7.
It also lacks healthy fats to aid in absorption and offers a brief, 30-day return policy.
*Results are based on the Smarter Reviews Ranking System and do not necessarily reflect typical results from the use of these products. Please visit product websites for more information.
Learn MoreDisclaimer:
Smarter Reviews is owned and operated by the same company that owns certain products featured on this website, including the products ranked number one.
In addition, we receive compensation from certain companies whose products are featured on this website when you purchase a product using the links on this website.
Go back to pageOur Main Sources
Sources used for research purposes. Smarter-Reviews.com are not officially affiliated with these sites.
What You Will Learn:
Estimated Read Time 5 Minutes
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