Here’s Why You Should Always Take Vitamins D3 & K2 Together

Here’s Why You Should Always Take Vitamins D3 & K2 Together

You may not experience the extensive health benefits of vitamin D3 if you don’t have enough vitamin K2 to transport the D3 through your body. Together, these fat-soluble vitamins support bone health, heart health, and immune function.

Vitamin D is sometimes referred to as the ‘sunshine vitamin’ because the body produces it through exposure to sunlight. As most of us spend a majority of our time indoors, it’s not a surprise that vitamin D deficiency is incredibly common.

Most people are vitamin D3-insufficient, and even more people don’t get the proper amount of vitamin K2. Low vitamin D levels and vitamin K levels can lead to serious health problems, such as fatigue, depression, and heart disease.

Recent research reveals vitamin D3 needs vitamin K2 to benefit whole body wellness. Plus, vitamin K2 offers significant health benefits of its own.

Keep reading for more details on why you should always take vitamin D3 and K2 together.

Vitamin D3 Vitamin K2
Primary function Calcium absorption into blood Transfer of calcium to bone
Other benefits • Immune regulation and disease prevention
• Lower risk of heart disease
• Mood and mental health
• Healthy weight management
 Thyroid health
• Lower risk of heart disease
• Healthy blood clotting
• Reduced risk of osteoporosis
• Improved insulin sensitivity
• Reduced cancer risk
• Improved fertility
Food sources • Fatty fish
• Egg yolks
• Mushrooms
• Certain cheeses
• Cod liver oil
• Fermented foods
• Natto
• Sauerkraut
• Egg yolks
• Organ meats
• Grass-fed meat and cheeses
Suggested supplement dosage 25-100 mcg/day 100-200 mcg/day


How Vitamins D3 and K2 Work Together

Vitamin D3 promotes calcium absorption into your bloodstream, plus it regulates immune function. Vitamin K2 activates the matrix GLA protein (MGP) to absorb excess calcium into the bone mass and promote healthy blood flow, as well as to support healthy blood clotting.

Too much vitamin D3 (cholecalciferol) without enough vitamin K2 may lead to hypercalcemia (high blood calcium levels) in your arteries and soft tissues.

Too much vitamin K2 without enough vitamin D3 may lead to blood clotting and hypocalcemia, which means low levels of blood calcium.

Taking both vitamins together provides many health benefits, not just healthy calcium levels and bone strength. D3 and K2 support a healthy heart, strong teeth, and healthy aging.

Menaquinone-7 is the most potent form of vitamin K, whereas vitamin K1 (phylloquinone) is not as well-absorbed and doesn’t offer the same potency. Vitamin D3 is the more potent form of vitamin D, whereas vitamin D2 is the weaker form synthesized from sunlight.

Bone Health

About 20% of women over age 50 will be diagnosed with osteoporosis, especially postmenopausal women. Many more may have undiagnosed or subclinical bone weakness. Fortunately, vitamins D3 and K2 work together to support healthy bones.

Studies show that vitamin D3 and vitamin K2 may increase bone mineral density while reducing fracture risk and bone loss, particularly after menopause. Bone health is probably the most direct benefit of this pair of vitamins.

Cardiovascular Health

Every 33 seconds, someone in the United States dies of heart (cardio) or blood vessel (vascular) disease. Heart health is a serious problem for most Americans, but certain vitamins may help reduce your risk of heart disease — including vitamins D3 and K2.

Supplementing vitamin D3 and K2 may protect your arteries from getting blocked up. A double-blind placebo study found that D3 plus K2 may reduce certain heart diseases, opening up the future for larger randomized studies.

Dental and Oral Health

Keeping your teeth healthy is an important part of whole-body health since dental health conditions may impact brain health, heart health, and immune system function. Vitamins D3 and K2 may support dental health in many ways.

First of all, vitamin K2 is required for good bacteria to grow in your mouth. Also, low vitamin K2 status and vitamin D status have been linked to a higher risk of gum disease. Finally, vitamin D3 has been found to significantly improve dental enamel after demineralization.

Aging and Vitality

Everyone ages. There are a few ways to help slow or reverse aging, increasing your youthful appearance and reducing your risk of age-related diseases. Vitamin D3 and K2 are the best dietary supplements to support healthy aging

According to multiple studies, vitamin K2 reduces inflammation (anti-inflammatory), fights oxidative stress (antioxidant), and lowers the risk of age-related illness (anti-aging). Vitamin D is vital for immune function and cellular function, which can help prevent age-related disease.


Vitamins D3 and K2 improve immune function by supporting healthy bones and a strong heart.

Vitamin D is a popular and proven way to boost immunity, but vitamin K2 also works with vitamin D to regulate immune function and reduce inflammation. Some research indicates vitamin D supplements may reduce autoimmune diseases by 22%.

Try PrimeHealth Vitamin D3 + K2

In the last 5 years, new research has been mounting that supports the combination of a D3+K2 multivitamin to help with bone health, heart health, and so much more!

Visit the PrimeHealth store to learn more about supplements to support better health.


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by Dr. Soyona Rafatjah – February 16, 2024