Last Updated on March 31, 2025

WHAT ARE VITAMIN D OPTIMAL LEVELS?

Your body uses Vitamin D to absorb minerals like calcium, phosphorus, and to a lesser extent magnesium. And Vitamin D is also vital for the growth and health of bones & teeth, it also supports your muscles, nerves, and immune system.
You can get Vitamin D from sunshine on your skin and that’s why it’s called the Sunshine Vitamin.

Vitamin D Deficiency

Symptoms of Vitamin D deficiency include bone pain, muscle aches or weakness, fatigue, increased blood pressure, and depression. If it goes on long term, a Vitamin D deficiency can lead to softening of the bones, and ailments like Osteoporosis & Osteomalacia.

People at higher risk of deficiency include the elderly or obese people, people who don’t get enough sun exposure, people with darker skin, and people who take certain medications for long periods of time.

There is evidence that Vitamin D deficiency may increase the risk of some cancers, diabetes, immune diseases, and cardiovascular disease. Research suggests that women with low levels of Vitamin D have a higher risk of breast cancer.

People who do not have adequate sun exposure may obtain Vitamin D from food sources or supplements. Food sources include salmon, fatty fish, egg yolks, mushrooms, fortified milk & cereals.. .

Vitamin D & COVID-19

From influenza and the common cold to COVID-19, adequate levels of vitamin D helps your body combat illness.

Vitamin D inhibits the production of pro-inflammatory cytokines and increases the production of anti-inflammatory cytokines. There are multiple studies suggesting a link between low Vitamin D levels and an increased risk of catching COVID or developing more severe symptoms from the virus.

Vitamin D Optimal Levels

The Endocrine Society defines vitamin D deficiency as a 25-hydroxyvitamin D blood level below 20 ng/mL (50 nmol/liter) and vitamin D insufficiency as a level between 21–29 ng/mL (52.5–72.5 nmol/liter).
Health experts assert that the optimal range should be between 30–40 ng/mL (75–100 nmol/liter). In some research studies, Vitamin D levels in this range have been shown to reduce your risk of developing cancer and improve your immune system. Achieving it may require supplementation with a high-potency Vitamin D3 supplement.

If your level is above 35 ng/mL (87.5 nmol/liter), taking a Vitamin D supplement may be doing more harm than good, so consider cutting back.

Hint: 1 nmol/liter = 0.4 ng/mL

Vitamin D Recommended Dosage

Vitamin D comes in two major forms, vitamin D2 (ergocalciferol) and vitamin D3 (cholecalciferol). The human body can absorb and process both forms. However, as Vitamin D3 occurs naturally as your body’s response to sunlight, it’s generally considered the preferred form of supplementation.

The current recommendations suggest consuming 400–800 IU (10–20 mcg) of Vitamin D3 per day. People who need more vitamin D can consume 1,000–4,000 IU (25–100 mcg) daily. Supplements with higher Vitamin D dosages should be consumed on a weekly basis.

Hint: Be aware that too much Vitamin D can increase calcium levels, which in turn can lead to certain health complications. Taking Vitamin D with magnesium can help regulate Vitamin D levels in the body, which in turn manages the levels of other minerals such as calcium and phosphorus.

Reference
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7385774/