Vitamin D is an important nutrient required for the proper functioning of the muscle, heart, lung and brain. This vitamin helps your body absorb minerals, such as calcium and phosphorus, needed for the formation of bones.
The intake of vitamin D through foods or supplements benefit your health in many ways, such as losing weight, supporting bone health, lowering depression, protecting against heart disease and so on.
1. Hypercalcemia
Vitamin D toxicity leads to hypercalcemia, a condition that occurs when the calcium levels in your blood are above normal. High levels of vitamin D leads to an increase in calcium that your body absorbs and this can cause a range of complications, such as loss of appetite, confusion and high blood pressure [1].
2. Kidney damage
Having high amounts of vitamin D can lead to kidney damage. It is because an excessive amount of vitamin D increases calcium levels in the blood, which leads to kidney damage. A study showed that vitamin D toxicity can lead to acute kidney injury [2].
3. Weak bones Vitamin D in excess amounts causes bone loss and brittle bones. It is because high levels of vitamin D lead to low levels of vitamin K2 in the blood. The primary function of vitamin K2 is to preserve calcium in the bones and taking excess of vitamin D can reduce the activity of vitamin K2 [3]. The symptoms of brittle bones are painful bones, severe back or joint pain, increased risk of fractures and instability.
4. Irregular heartbeat
Excessive intake of Vitamin D causes hypercalcemia and this, in turn, can alter the proper functioning of the heart’s cells, which leads to irregular heartbeat. High levels of calcium cause calcium deposits to develop in the arteries of the heart, which can increase the risk of heart attack [4]. The symptoms are chest pain, exhaustion and dizziness.
5. Lung damage
High levels of vitamin D increase the levels of calcium and phosphate in the blood that combine together to form crystals. These crystals are more likely to accumulate in the lungs, which can impair its function, thus causing lung damage. The symptoms are coughing, difficulty in breathing and chest pain.
6. Dehydration
As vitamin D toxicity increases the calcium levels in the blood, it can pose a risk to the kidneys’ ability to concentrate urine. This results in uncontrollably passing large quantities of urine, which in turn causes dehydration.
7. Nausea and vomiting
Nausea and vomiting are other side effects of taking excessive amounts of vitamin D, which occurs when there are increased levels of calcium in the blood [5].
8. Stomach pain
Vitamin D toxicity leads to an increase in calcium levels, which in turn causes severe stomach pain. It also causes other digestive problems such as constipation and diarrhoea [6].
9. Pancreatitis
High intake of vitamin D elevates calcium levels and this can cause acute pancreatitis-it is an inflammation of the pancreas. The symptoms of acute pancreatitis include losing weight, pain in the upper part of the stomach and fever. Other risks of taking high doses of vitamin D are dry mouth, loss of appetite, exhaustion, continuous headaches, muscle weakness, changes in gait, high blood pressure, tinnitus, hearing loss, coma and gastric ulcers.