15 Nutritional Deficiencies That Develop Slowly and Are Frequently Missed

7. Vitamin K Deficiency - The Overlooked Bone and Heart Protector

Vitamin K deficiency is increasingly recognized as a significant health concern, particularly in older adults, yet it remains one of the most underdiagnosed nutritional deficiencies. This fat-soluble vitamin exists in two main forms: K1 (phylloquinone) found in leafy green vegetables, and K2 (menaquinones) found in fermented foods and produced by gut bacteria. While vitamin K is best known for its role in blood clotting, it's also essential for bone metabolism and cardiovascular health through its activation of proteins like osteocalcin and matrix Gla protein. Subclinical vitamin K deficiency, where clotting function remains normal but other vitamin K-dependent proteins are undercarboxylated, is surprisingly common. This condition is associated with increased risk of osteoporosis, arterial calcification, and cardiovascular disease. Symptoms of deficiency are often subtle and develop slowly, including easy bruising, excessive bleeding from minor cuts, weakened bones, and potentially increased arterial stiffness. Risk factors include inadequate dietary intake of leafy greens, malabsorption disorders, antibiotic use that disrupts gut bacteria, and certain medications like warfarin. The modern Western diet, often low in vitamin K-rich foods, combined with reduced gut bacteria diversity due to antibiotic use and processed food consumption, contributes to widespread subclinical deficiency.