Vitamin D: Why So Deficient in the Land of Sunshine?

It is one of the most frequent paradoxes in our medical analysis laboratory in Tangier: patients living under some of the best sunshine in the world… and a low vitamin D result. Vitamin D deficiency is actually very widespread in Morocco as elsewhere — and since its signs are vague (fatigue, aches), the blood test is what settles it.

What is vitamin D for?

Its central role is bone: vitamin D allows calcium from food to be absorbed and fixed onto the skeleton. It also contributes to proper muscle function and to the immune system. Prolonged deficiency weakens bone — up to osteoporosis in adults and rickets in children in severe forms — and can show up much earlier as lasting fatigue, diffuse bone or muscle pain, cramps. That is why its testing is often combined with the calcium-phosphorus panel, the three being inseparable.

Why deficient, with all this sun?

Because vitamin D hardly comes from the plate: the skin makes it under the sun's UV rays. But our lifestyles have changed — indoor days, car travel, skin covered by clothing, sunscreen — and darker skin, more protective, also makes vitamin D more slowly for the same exposure. The result: living in a sunny country guarantees nothing, and studies find very frequent deficiencies in Morocco, particularly among women. Food (oily fish, eggs, fortified dairy) helps but is generally not enough to correct a real deficiency.

When to test vitamin D?

On prescription, typically in these situations: unexplained fatigue or aches, osteoporosis or fractures, repeated falls in the elderly, pregnancy and breastfeeding according to follow-up, digestive diseases that hinder absorption, interfering treatments. The blood test (25-OH vitamin D) is simple: no fasting needed, any time of day. The report situates your result against reference values — its interpretation, and the decision to supplement, belong to your doctor.

Supplementing: yes, but never solo

Correcting a deficiency works very well — with a prescribed regimen, suited to your starting level and situation, then sometimes a control test. What not to do: string together, on your own initiative, high doses bought without prescription. Vitamin D is stored in the body, and its excess is not harmless (it raises blood calcium). Between "land of sunshine" and "vial after vial", the right path goes through a test, then a medical decision.

Frequently asked questions

Should I fast before a vitamin D test?

No. The test can be done at any time of day, alone or within a panel — if other tests on your prescription require fasting, they are the ones setting the conditions.

What are the signs of deficiency?

They are unspecific: lasting fatigue, diffuse bone or muscle pain, cramps, low mood. Precisely because these signs can have a thousand causes, only the blood test can tell.

I am in the sun every day — can I still be deficient?

Yes. Short exposure or at the wrong hours, covered skin, sunscreen, darker skin, age: many factors reduce synthesis. It is the classic paradox of sunny countries — the test settles it, not the impression.

Which foods provide vitamin D?

Oily fish (sardine, mackerel, salmon), eggs, fortified dairy products. A useful complement, but rarely enough to correct an established deficiency — hence prescribed supplementation when necessary.

Is too much vitamin D possible?

Yes — not from sun or food, but from prolonged high doses taken without follow-up. Excess raises blood calcium, with real consequences. That is why supplementation is done on prescription, not self-service.

What about pregnancy or babies?

Needs change during pregnancy and in infants — your doctor or the paediatrician decides on testing and possible supplementation, integrated into usual follow-up.

To go further: our articles on fasting before a blood test and the value of an annual blood checkup.