Vitamin D supplement: when to take and recommended dose
Tatiana Zanin
Nutritionist
April 2020
Vitamin D supplements are recommended when the person is deficient in this vitamin, being more frequent in colder countries where there is little exposure of the skin to sunlight. In addition, children, the elderly and people with darker skin are also more likely to be deficient in this vitamin.
The benefits of vitamin D are related to the good health of bones and teeth, with increased muscle strength and balance, and with decreasing the risk of diseases such as diabetes, obesity and cancer.
Vitamin D supplements can be found in pharmacies, supermarkets, health food stores and on the internet, in capsules for adults or in drops for children, and the dose depends on the person’s age.
When the supplement is indicated
Vitamin D supplementation is indicated by the doctor in order to treat some conditions that may be related to low amounts of vitamin D circulating in the blood, such as:
- Osteoporosis;
- Osteomalacia and rickets, which result in increased fragility and deformity in the bones;
- Very low levels of vitamin D;
- Low calcium levels in the blood due to decreased levels of parathyroid hormone, parathyroid hormone (PTH);
- Low levels of phosphate in the blood, as in Fanconi Syndrome, for example;
- In the treatment of psoriasis, which is a skin problem;
- Renal osteodystrophy, which occurs in people with chronic renal failure due to the low concentration of calcium in the blood.
It is important that before starting to use vitamin D supplementation, a blood test is done to know the levels of this vitamin in the blood, so that the doctor can inform you of the recommended daily dose, for example. Understand how the vitamin D test is done.
Recommended dose of vitamin D supplement
The recommended dose of the supplement depends on the person’s age, the purpose of the supplement and the levels of vitamin D identified in the test, which can vary between 1000 IU and 50000 IU.
The following table indicates the recommended dose for the treatment and prevention of some diseases:
| goal | Need for vitamin D3 |
| Prevention of rickets in babies | 667 UI |
| Prevention of rickets in premature babies | 1,334 UI |
| Treatment of rickets and osteomalacia | 1,334-5,336 IU |
| Complementary treatment of osteoporosis | 1,334- 3,335 UI |
| Prevention when there is a risk of vitamin D3 deficiency | 667- 1,334 IU |
| Prevention when there is malabsorption | 3,335-5,336 UI |
| Treatment for hypothyroidism and pseudo hypoparathyroidism | 10,005-20,010 UI |
It is important to keep in mind that the recommended dose should be indicated by the responsible health professional and, therefore, it is important to consult the doctor or nutritionist before consuming the supplement. Learn more about vitamin D and its functions.
Secundary effects
Ingested vitamin D is stored in the body and, therefore, doses above 4000 IU of this supplement without medical advice can cause hypervitaminosis, which can cause nausea, vomiting, increased urinary frequency, muscle weakness and constipation.
In addition, doses higher than recommended by the doctor can favor the deposition of calcium in the heart, kidneys and brain, which can have serious consequences.
Contraindications
Vitamin D supplementation should not be used by children, pregnant or breastfeeding women, people with atherosclerosis, histoplasmosis, hyperparathyroidism, sarcoidosis, hypercalcemia, tuberculosis and by people with kidney failure without medical advice.
Watch the following video and also find out which foods are rich in vitamin D:
