Bio-Avail D3/K2

3-6 month supply

A Highly Absorbable Blend of Vitamins D3 and K2

Bio-Avail D3/K2

3-6 month supply

A Highly Absorbable Blend of Vitamins D3 and K2

Restore optimal D3 and K2 levels with this clean, easy-to-absorb, liquid formula.

  • Supercharge your immune, metabolic, cardiovascular, and bone health

  • Flexible dosing: 1,000 IU of D3 and 120 mcg of K2 per one-drop serving

  • Only 3 ingredients: MCT oil, D3, and K2. No artificial fillers or junk!

  • High-potency formula (600 servings per bottle!) saves you money and time.

Purchase type options
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60-day Returns


Overcome Vitamin D Inadequacy (>90% of Americans)

Support immune function, heart and metabolic health, mood, cognitive function, strong bones


Protect Your Bones and Heart

Experience the synergistic benefits of D3 and K2 for cardiovascular and bone health.


Fine-Tune Your Daily Dose

With 1,000 IU of D3 and 120 mcg of K2 per drop, our flexible liquid formula makes it easy to get exactly the amount you need.


Affordable and Efficient D3/K2 Benefits

Our high-potency formula provides a clean source of D3/K2 at less than 6 cents per serving.

Powerful Nutrients & Vitamins

Vitamin D3

Vitamin D3

1,000 IU of vitamin D3 in a highly absorbable, liquid form. Avoid seasonal fluctuations of vitamin D levels and optimize your intake no matter where you live or what time of year it is. 

Vitamin K2

Vitamin K2

120 mcg of vitamin K2 in both MK-4 and MK-7 forms (60 mcg of each). Get the full benefits of vitamin K2 by taking the two most effective forms together.



MCT oil is a perfect carrier for D3 and K2 because it is rapidly absorbed and is a great energy source. It has a clean, neutral taste with no sweeteners, artificial flavors, binders, or fillers.

Real Stories of Health and Happiness

  • "Great price for a high quality vitamin D that will last a VERY long time."

    —Lauren, Verified
  • “I really like the fact that these two vitamins are combined in liquid form.”

    —Dianne, Verified
  • “This is so easy to take daily!”

    —Michelle, Verified

Discover the Bio-Avail D3/K2 Advantage

Natural, whole-food
Synthetic, fillers
Maximally absorbable
Low absorption
Health Focus
Addresses root causes
Addresses symptoms
Clinical Background
15 years in-clinic
Not typically
Supports soil health
Disregards soil health
Single-use plastics
Functional Medicine expert

Meet Chris Kresser, your
Trusted Health & Wellness Guide

Founder & Functional Medicine Clinician

  • Globally renowned expert with over 15 years of experience
  • Dedicated to helping people improve their health by addressing modern challenges and nutrient gaps

Author & Educator

  • Treated thousands of patients
  • Trained more than 2,000 healthcare professionals
  • Gained valuable insights into functional medicine and nutrition

Why choose Bio-Avail D3/K2?

Our modern diets often fall short of providing the optimal amounts of essential nutrients our bodies need to function at their best. With the Bio-Avail D3/K2, you can overcome nutrient deficiency and support your overall health and well-being. We've done the research, so you don't have to!

Formulated to Replicate Optimal Ancestral Diets

Changes in dietary patterns, declining soil quality, and a growing toxic burden have made it increasingly difficult to obtain adequate nutrients from our daily food intake. Most Americans don’t get enough vitamin D and K2—with potentially serious consequences. With just a few drops of Bio-Avail D3/K2 daily, you’ll never have to worry about falling short of these critical nutrients again!

Harness Years of In-Clinic Experience and Ancestral Wisdom

Backed by Adapt Naturals' 15 years of in-clinic experience and dedicated to creating supplements that make a meaningful difference, Bio-Avail Omega+ combines cutting-edge research with insights from ancestral wisdom to bring you a premium-quality supplement.

Signs You Need Bio-Avail D3/K2

Frequent colds & flu

Low mood

Weak bones

Metabolic difficulties

Brain fog, poor memory

Cardiovascular risk

What You'll Feel Using Bio-Avail D3/K2

  • Better immune function

  • Stronger bones

  • Sharper mind

  • Elevated mood

  • Healthier metabolism

  • Improved cardiovascular function

  • Greater longevity

Bio-Avail D3/K2

Unlock Your Optimal Health

Upgrade Your Wellness with Bio-Avail D3/K2—Lifelong Health, Simplified

Get Healthier & Happier - Try Now

Your Questions Answered

Take one to five drops per day with or without food as directed by your healthcare provider. The optimal dosage will depend on your individual needs and whether you take vitamin D3 and/or K2 in other products.

We suggest consulting with your healthcare provider to determine your optimal dose of vitamins D3 and K2. Bio-Avail Multi contains 2,000 IU of vitamin D3 and 50 mcg of vitamin K2. Bio-Avail D3/K2 contains 1,000 IU of vitamin D3 and 120 mcg of K2 per serving/drop. This makes achieving your optimal dose of both nutrients easy according to your healthcare provider’s recommendations.

The shelf life is two years.

The MCT oil is derived from coconuts. This product is not suitable for people who are allergic to coconuts.

No, it is not vegan. The vitamin D3 is sourced from lanolin, which comes from the glands of wool-bearing animals.

Customer Reviews

Based on 16 reviews
Richard Scranton
Very enjoyable

I enjoy taking my d/k drops daily.

Hi Richard, We are glad to know you are enjoying our D3/K2 supplement. Thank you for reviewing this product!

Alex Ivankovitser
Bio-Avail D3/K2

I’ve purchased other brands before switching to the Adapt Naturals and the number one ingredient I prefer is the MCT oil over olive or other oils added for taste. I feel more energized daily using the Adapt Naturals brand.

Hi Alex, We are happy to know you have noticed a difference in your energy since you started our D3/K2 supplement. Thank you for leaving us a review! All the best.

Andrew Bufkin
Improved muscle recovery time

I have returned to the fitness world around 6 months ago and of course recovery is the biggest struggle and I too often had to rest for too many days because I was too sore or my shoulders hurt too bad.
THEN...I purchased the BIO-Avail D3/K2 and I'm seriously seeing so many results! I take 5 drops a day and then I do 10 drops on my rest days and I recover SO SO much quicker. My energy level is up too!!

Hi Andrew, We are pleased to hear our D3/K2 has helped you to recover faster when you exercise. We appreciate your support to Adapt Naturals. Thank you for leaving us a review!

George Henry

I like them . I will keep buying.

Hi George, We are happy you are loving our D3/K2.Thank you for supporting Adapt Naturals, We appreciate your review!

Rochelle Marie
Bio-Avail D3/K2

Love that there’s enough doses in the bottle for the entire family to use—- great deal!

Hi Rochelle, We are happy the dosage in the D3/K2 is enough to supplement you and your family. Thank you for reviewing this product. We appreciate your support to Adapt Naturals!