on December 01, 2025

Causes of Vitamin K2 Deficiency

Introduction

Vitamin K2 plays a vital role in maintaining strong bones, supporting heart health, and regulating how calcium moves through the body. Despite its importance, many people don’t realize they’re not getting enough of it. Below are six of the most common reasons why vitamin K2 levels can become low.

1. Not Enough K2 in the Diet

One of the main causes of low vitamin K2 is simply not consuming enough foods that contain it. This is especially common among people who follow vegetarian or plant-based diets, since most naturally rich sources of K2 come from animal products or fermented foods. In many Western-style diets, foods like natto (fermented soybeans), which are exceptionally high in K2, are rarely eaten.

2. Poor Nutrient Absorption

As we grow older, the body’s ability to produce digestive enzymes naturally decreases. When enzyme activity slows down, it becomes harder to absorb nutrients, including fat-soluble vitamins such as K2. Even if you eat K2-containing foods, reduced absorption can still lead to deficiency.

3. Imbalanced Gut Bacteria

A healthy gut microbiome helps produce and absorb vitamin K2. When the balance of bacteria is disrupted—meaning harmful bacteria outnumber beneficial ones—it can interfere with the body’s ability to create and utilize K2 effectively.

4. Issues With Fat Digestion

Since vitamin K2 is fat-soluble, your body needs proper fat digestion to absorb it efficiently. Problems with the liver or gallbladder can impair this process. Conditions such as bile insufficiency, gallstones, or reduced liver function may all weaken fat absorption, making it harder for the body to use vitamin K2.

5. Antibiotic Use

Antibiotics can be lifesaving, but they also disrupt the gut bacteria that play a role in vitamin K2 production. Long-term or frequent antibiotic use may significantly reduce K2 levels by damaging the beneficial bacteria needed for its synthesis.

6. Certain Medications

Some medications can negatively impact vitamin K2 absorption or alter gut flora, including:

  • Proton pump inhibitors (acid reflux medications)

  • Anti-seizure medications

  • Treatments for certain chronic conditions

These medications may reduce the body’s ability to properly absorb or produce vitamin K2.

REFERENCE: J9CON230271