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

Dr. Mercola Vitamins D3 & K2

Promoted as a Vitamin D3 & K2 supplement for bone, joint, blood, and immune health, Dr. Mercola Vitamins D3 & K2 seems like any other D3+K2 supplement. However, closer examination of the ingredients reveals a number of differences. The inactive ingredients in this formula outnumber the active ingredients. You should always be wary when there are too many inactive ingredients because they could weaken the effectiveness of a product and can sometimes cause harmful interactions. 

Dr. Mercola Vitamins D3 & K2 contains inactive ingredients such as maltodextrin, sucrose, and modified starch. This means that there are carbs (maltodextrin), sugar (sucrose), and starch in these capsules. While these each have their place in a balanced diet, they have no place in a supplement. These ingredients serve to help with the manufacturing process. However, if you eat like most Americans, odds are that your diet doesn’t have room for extra, unnecessary sugar and carbs.  You probably don’t want to swap out the sugar in your diet for sugar that’s inside a pill and you can’t even enjoy.

Is Dr. Mercola Vitamins D3 & K2 Effective?

This formula consists of the recommended dosage of 5000 IU Vitamin D3 paired with 180 mcg K2 as MK-7. Based on the dosage of D3, we do believe that this supplement should be effective. Dr. Mercola doesn’t provide the consumers with the percent of trans that the K2 is (how active it is) but does state that the K2 is produced from chickpeas which they claim is one of the most bioavailable and stable types.

One thing we would have liked to see in this formula is a bioavailability enhancer, such as BioPerine. When it comes to nutrition, the most important thing is absorption so bioavailability enhancers, which improve absorption, make a supplement highly effective. Unfortunately, Dr. Mercola did not recognize the value of such an ingredient when this Vitamins D3 & K2 supplement was crafted.

There were mixed reviews, however the majority of them did appear to be positive and some even shared the improvement in their Vitamin D levels. That said, there were some complaints on Amazon about receiving broken bottles or bottles with broken seals. So long as you receive a bottle that is intact, you should likely be satisfied. 

Is Dr. Mercola Vitamins D3 & K2 Safe?

There are no mentioned side effects of taking this product. As with any new supplement or diet introduced into your daily life, we always advise talking to your healthcare professional about possible contraindications of any pre-existing medical conditions or medications that you are taking, especially if you are taking anticoagulant medication. Supplements work differently for everyone and the effects vary between individuals so it is always a good idea to run any health changes with a professional.

We noted that the manufacturer makes no mention of third-party testing which would guarantee that the product has been tested by an independent company that verifies the quality and purity of this supplement.


Dr. Mercola Vitamins D3 & K2 seems to be an effective Vitamin D supplement. It doesn’t contain any “harmful fillers, preservatives, or processing aids” but does contain sugar and carbs which is something that you should take into account regarding your diet. Its pricing isn’t terrible but there are cheaper options. For example, the best cost saving option for Dr. Mercola Vitamins D3 & K2  is to buy a three month supply for $79.97 (at $26.65 per month) but our top choice offers a 6 month supply for $139.8 (23.3 per month). When it comes down to it, 3 dollars a month starts to add up. Lastly, this product contains the full dosage in one pill which leaves little room for adjustments down the road once your levels improve. In short, we like this product and think it rightly deserves the third spot on our list of top products.

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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