Vitamin D

What is Vitamin D?

Vitamin D is a fat-soluble vitamin typically synthesized via UV light exposure or obtained from food or supplements. Normal levels are essential for an effective immune system and healthy mineral balance. Vitamin D is vital for its role in calcium absorption, bone mineralization, and reducing inflammation, and even has neuromuscular and metabolic functions.

Why is Vitamin D included in the Inflammation and Metabolic axes?

Evidence has shown that low concentrations of Vitamin D are associated with increased levels of inflammatory markers and an increased risk of Metabolic Syndrome. Metabolic syndrome is a cluster of conditions that occur together, increasing your risk of heart disease, stroke, and type 2 diabetes.

How can I better understand my results?

The National Library of Medicine has linked several Vitamin D levels with different health statuses. While these concentrations may help you interpret your results, it is important to consult with your physician if you have any concerns.

  • Moderate deficiency: < 12 ng/mL
  • Mild deficiency: 12-20 ng/mL
  • Insufficient: 20-30 ng/mL
  • Sufficient: 30-50 ng/mL
  • Critical: > 150 ng/mL

Lower levels have several health implications. It may lead to decreased bone health, muscular atrophy, and even more serious health problems depending on the levels such as rickets or osteomalacia. People at risk of deficiency are those who follow a vegan diet, do not get enough ultraviolet sun exposure, are obese, have undergone gastric bypass surgery, or have a disease such as IBD, ulcerative colitis, or Crohn's that disrupts the normal digestion of fat.

Higher levels can also be harmful, as it could lead to nausea, dehydration, kidney issues, and in severe cases anorexia, irregular heartbeat, or hardening of blood vessels and tissues.

If your Vitamin D levels are low, you can try:

  • Eat fatty fish like cod, herring, salmon, swordfish, trout, mackerel, or tuna
  • Fortified foods such as orange juice, cereal, or milk
  • Spend 15-20 minutes outside between 10 am and 3 pm without sunscreen
  • Try a UV lamp to naturally synthesize more Vitamin D without the sun
  • Take a 600 IU supplement, which is the recommended dietary intake
  • Exercise to release the Vitamin D sequestered in fat

Where can I learn more?

Harvard T.H. Chan School of Public Health - Vitamin D

National Institutes of Health - Vitamin D