Vitamin D Deficiency

What is Vitamin D Deficiency?

Vitamin D helps the body absorb calcium and phosphorus, which keeps bones and teeth strong, and it also supports muscle function and the immune system. Most vitamin D is made in the skin in response to sunlight; relatively few foods contain much of it. A lack of vitamin D can cause bone pain and muscle weakness and, over time, softening of the bones — osteomalacia in adults and rickets in children. Many people with low levels have no symptoms at all, so a blood test measuring 25-hydroxy vitamin D is the only reliable way to know your level. Laboratories and guidelines use somewhat different cut-offs, so your result should be read against the range on your report.

Symptoms

• ●Bone pain
• ●Muscle weakness
• ●Fatigue
• ●Depression
• ●Frequent infections
• ●Slow wound healing

What Causes Vitamin D Deficiency?

The main cause is too little sun exposure on the skin, which is common for people who spend most of the day indoors, cover most of their skin when outside, or use high-factor sunscreen consistently. Darker skin needs more sun to produce the same amount of vitamin D. Low dietary intake, obesity, conditions that affect fat absorption such as celiac disease, kidney or liver disease, and some medicines can also reduce vitamin D levels.

Risk Factors

• ⚠Mostly indoor lifestyle
• ⚠Clothing that covers most of the skin
• ⚠Darker skin tone
• ⚠Obesity
• ⚠Older age
• ⚠Pregnancy and breastfeeding

How to Prevent Vitamin D Deficiency

Regular, sensible sun exposure helps your skin make vitamin D, though in the UAE's strong midday sun it is important to avoid burning. Foods such as oily fish, egg yolks and fortified milk or cereals add smaller amounts. Many people need a supplement, but the dose should be guided by a test and your doctor: vitamin D builds up in the body, and taking too much over a long period can raise calcium to harmful levels.

When to Get Tested

Consider testing if you have bone pain, muscle weakness or persistent tiredness, or if you are in a higher-risk group: you spend most of your time indoors, cover most of your skin outdoors, have darker skin, are pregnant, are older, or have a condition that affects absorption. If you are taking a prescribed vitamin D supplement, a repeat test after a few months, as advised by your doctor, shows whether the dose is right. Calcium, phosphorus and parathyroid hormone are often checked alongside.

References & Sources

• [1]
  Cleveland Clinic — Vitamin D DeficiencyAccessed: 2026-02-14
• [2]
  NHS — Vitamin DAccessed: 2026-02-14