Vitamin D3 Product Buyer’s Guide (updated July 2024)

Information About Vitamin D3

Also known as cholecalciferol, Vitamin D3 is the form of Vitamin D that our bodies produce and it can also be consumed through animal products. Vitamin D is a vital nutrient for supporting bone health, the cardiovascular system, and the immune system. Combined with K2, this vitamin helps transport and absorb calcium into the bones. This process not only strengthens the bones but also prevents calcium from accumulating in the arteries and negatively impacting the cardiovascular system.

Vitamin d from sunlight

“D3+K2=better health” might just be the most important equation in your life. Okay, it’s probably not the most important equation but it is worth remembering. If you belong to the estimated 1 billion people with Vitamin D deficiency or the approximately 50% of the population with insufficient Vitamin D levels, then your health will most certainly benefit from a D3+K2 supplement.

Unfortunately, the market is saturated with low quality Vitamin D supplements that are inefficient and unhelpful. However, clinical studies have shown that many high quality products do actually work to raise Vitamin D levels and improve health. Our research has shown that given the correct dosage and potency of Vitamins D3+K2, you can achieve the results that you want. The bottom line is that there are Vitamin D products that will do exactly what they say they will – you just have to find them.

Key points to consider when choosing a D3+K2 supplement

There are several key elements which make a highly effective, top-quality Vitamin D3 supplement. These include an optimal dosage of 5000IU/125mcg D3 as recommended by the Vitamin D Council. For better results, it must be paired with Vitamin K2 which can be in either the MK-4 or MK-7 form. While MK-4 has been used for longer, MK-7 is actually more effective for raising Vitamin K levels and is being used in more and more multivitamins. To make it more complicated, MK-7 or -4 can be trans or cis isomers, meaning active or inactive chemical compounds. Most companies will not disclose the percentage of trans but what you really want is Vitamin K2 that is at least 80% Trans MK-7. Additionally, you should look for the inclusion of a bioavailability enhancer, such as BioPerine® to increase nutrient absorption and maximize the results. 

When choosing a D3+K2 supplement, you should look for a company with a strong reputation that sells a wide range of natural, nutritional supplements. An effective supplement will be formulated using high-quality ingredients, be GMP certified, and made in an FDA-approved facility. Many supplement manufacturer’s make grand promises of renewed health, only for you to find out later that there is no real change and you are left with an empty bottle, empty purse, and empty promises. Don’t be dismayed – there are some that really do work – you just need to find a legitimate product.

If you come across a company selling D3+K2 supplements using strong marketing terms or slogans, or if they are endorsed by famous celebrities, you should stay clear. If the company and product formula don’t speak for themselves, then nothing else should. 

What makes a D3+K2 supplement effective?

The secret is simply in the formula! The right dose of D3 and K2 plus third-party testing for purity and safety have been shown to be essential for an ideal Vitamin D supplement. 

Should you decide that a Vitamin D supplement is for you, and you would like to try a top-quality product, check out our reviews for a number of quality D3+K2 supplements that are currently available on the market. We examined numerous products for their ingredients, consumer feedback, business reputation and more, in order to help you discover which supplements are the real deal! No more guesswork. We have done all the hard work for you – your search for answers is over!

Our recommended choice stands above and beyond the competition and we think you will agree. The company’s excellent reputation, high-quality product, and external independent monitoring and testing are enough to earn a high ranking. When you consider all of those factors and the incredible money-back guarantee policy, Approved Science D3+K2 becomes a product that you are going to want to take a closer look at.

Vitamin D3 Report

Approved Science Vitamin D3+K2

Rating: Excellent


Money-Back Guarantee
Consumer Feedback
Company Reputation

Editor’s Choice

Approved Science Vitamin D3+K2

If you are looking to improve your bone, cardiovascular, and immune health then Approved Science Vitamin D3+K2 is something that deserves your undivided attention. Of all the Vitamin D supplements currently available on the market, this is the one that deserves a closer look and very likely, the one that will change your life!

It contains the recommended dosage of 5000 IU of Vitamin D3 combined with Vitamin K2 for a synergistic combination to ensure calcium is directed to the bones in an efficient and optimal manner. In addition to having the right vitamins, this formula uses the ideal forms of the vitamins (Vitamin D as D3 and K as K2 MK-7) in clinically researched amounts. It was the only product we found that contains BioPerine® to enhance nutrient absorption and consequent utilization for better results. It does not contain any additives or preservatives and is totally 100% safe to use with no long-term side effects.

Quality: Approved Science Vitamin D3+K2 contains high-grade, natural, clinically-verified ingredients that are GMP-certified.

Reputation: Approved Science’s reputation is top quality. They are well known in the industry and are an established company that provides great customer support service, secure and easy checkout as well as prompt, efficient delivery. This manufacturer has several third-party monitoring services, including buySAFE, Norton, and Trustee, as well as an A+ rating from the quality monitoring company QualityTrusted. Approved Science’s commitment to the health industry and consumers is excellent, providing further legitimacy to their products by producing them in an FDA-registered laboratory.

Money-Back Guarantee: Every item sold is supported by a 60-day 100% money-back guarantee. Such guarantees from manufacturers show strong confidence in their products’ ability to deliver results. Great news for consumers.

Bottom Line: If you are looking for a product that ticks all the boxes for an effective Vitamin D supplement that comes from an established reputable company with an excellent money-back guarantee, then this is the supplement for you.

It would be good to note that, due to high demand, Approved Science Vitamin D3+K2 is often sold out. To avoid having to back order, don’t hesitate to make that purchase when you see it in stock.

See The Full Review


Rating: Good



Dr. Mercola Vitamins D3 & K2

Marketed as a supplement that improves bone & joint comfort, blood flow, and immunity, Dr. Mercola’s Vitamins D3 & K2 is our second choice. With 5000 IU of Vitamin D3 and 180 mcg of K2, this product seems to have it all, except a bioavailability enhancer. Nevertheless, there are a few reasons it didn’t rank higher.

The price on this is quite fair though there are some cheaper options. It was unclear to us whether or not the manufacturer offers a satisfaction guarantee. The return policy has two options depending on your membership with Mercola Market. Non-expired consumables can be returned for up to 90 days or 1 year depending. However, there is no clarification on whether this refers to opened or only unopened products.

Dr. Mercola’s Vitamins D3 & K2 is made according to the GMP guidelines and the manufacturer checks the product throughout the process. However, there is no mention of third-party testing which adds assurance that each element is what it’s supposed to be. We appreciate the claim that Dr. Mercola’s Vitamins D3 & K2 is made without any harmful fillers or binders. Yet, this doesn’t exclude the “non-harmful” binders, fillers, and anticaking agents that it does contain. Read our full review for a deeper understanding of this formula and its price.

Click here to read the full review


Rating: OK


Designs For Health Vitamin D Supreme

Our third pick is a Vitamin D supplement that is vegetarian, dairy-free, and soy-free. Providing the clinically recommended dosage of 125 mcg Vitamin D, Vitamin D Supreme also contains a combination of 500 mcg K1 and 50 mcg K2. But is it as effective as a product with only K2 but in a more significant dosage and no K1? 

When reviewing this product, we were pleased to see a price tag that suggests quality – not cheap, but affordable. We appreciate that this product is formulated with the optimal vitamin types according to clinical studies. However, we were a little puzzled that the K2 dosage wasn’t as high as other science-based products. Nevertheless, with 125 mcg of D3, this product had the right amount to qualify it for our top Vitamin D products. 

We also liked that the product comes from a well established brand and the overall reviews for this product were positive. The manufacturer follows the GMP guidelines and guarantees their products are what they are supposed to be. Yet, unlike our top pick, this product does not undergo third-party testing and there is no satisfaction guarantee. Read our full review for more about how this product stacks up.

Click here to read the full review

What You’ll Discover:

Which Vitamin D3 supplement is the BEST BUY and comes with a great GUARANTEE!
Which formula and ingredients are the most EFFECTIVE and work the fastest?
How NOT to get ripped off! BE AWARE of poor quality and cheap products.

Top 6 Items to Consider:

  1. Ingredients
  2. Cost Per Serving
  3. Product’s Testing Results
  4. Company’s Reputation
  5. Consumer Reviews
  6. Return Policy & Satisfaction Guarantee

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