The main consequence of vitamin D toxicity is a buildup of calcium in your blood (hypercalcemia), which can cause nausea and vomiting, weakness, and frequent urination. Vitamin D toxicity might progress to bone pain and kidney problems, such as the formation of calcium stones.
Excess levels of vitamin D in your system can lead to an array of complications and symptoms, including weakness and fatigue.
Side effects of vitamin D supplements may include constipation and dry mouth. Extremely high levels of vitamin D are harmful, and can cause nausea, vomiting, confusion, excessive thirst and kidney stones. Vitamin D supplements can interact with certain medications, so check with your doctor before starting one.
Vitamin D is vital for physical and mental health. A vitamin D deficiency can impact your mood, meaning it may contribute to feeling down or depressed.
Some side effects of taking too much vitamin D include weakness, dry mouth, nausea, vomiting, and others. Taking vitamin D for long periods of time in doses higher than 4000 IU (100 mcg) daily is possibly unsafe and may cause very high levels of calcium in the blood.
Together with calcium, vitamin D also helps protect older adults from osteoporosis. Vitamin D has other roles in the body, including reduction of inflammation as well as modulation of such processes as cell growth, neuromuscular and immune function, and glucose metabolism [1-3].
Because vitamin D toxicity can cause side effects like rapid heartbeat, confusion, restlessness and chest pains, it can potentially cause feelings associated with anxiety.
Extremely high vitamin D levels are harmful and can cause nausea, vomiting, confusion, excessive thirst and kidney stones. Vitamin D supplements can interact with certain medications, so check with your doctor before starting one.
Growing evidence has demonstrated that vitamin D has a role in sleep regulation [12]. Specifically, vitamin D deficiency (VDD) can increase risk of sleep disorders and is associated with sleep difficulties, shorter sleep duration, and nocturnal awakenings in children and adults [13,14,15].
According to the National Institutes of Health, vitamin D promotes calcium absorption in the gut and helps regulate the concentration of calcium and phosphorus in the blood, which supports building and maintaining healthy, strong bones and helps regulate skeletal and neuromuscular function.
Hypercalcemia
Excessive intake of vitamin D can increase the calcium level in the blood, and can cause harmful effects like fatigue, dizziness, excessive thirst, frequent urination, etc.
Those with the lowest levels should feel an improvement after just a few days, while those who only need to top up their levels may have to wait a week or two before they begin to feel healthier and more energised.
Therefore, conditions that affect the gut and digestion, like celiac disease, chronic pancreatitis, Crohn's disease, and cystic fibrosis, can reduce vitamin D absorption.
If you have too much vitamin D in your blood, it will cause extra calcium absorption. This, in turn, can lead to symptoms like muscle pain, mood disorders, abdominal pain, frequent urination and kidney stones.
That's because vitamin D seems to help mitochondria—the part of a cell that generates energy—use oxygen and power various parts of the body, including muscles.
Kunutsor et al suggested that supplementation with vitamin D significantly reduced diastolic blood pressure (DBP) by 1.31 mm Hg in participants with preexisting cardiometabolic conditions (16).
Vitamin D (from food, sunshine and supplements) changes to calcidiol in the liver, which is measured from blood to check the level of vitamin D. The half-life of calcidiol of D3 (we get from supplements and e.g. fish) is 15–30 days. Half-life is the period during which vitamin D stores decrease by half.
Vitamin D stimulates hair follicles to grow, and so when the body does not have enough, the hair may be affected. A vitamin D deficiency may also be linked to alopecia areata, an autoimmune condition that causes patchy hair loss.
Too much or too little of necessary nutrients, such as vitamin D, can cause significant health problems. That being said, when you intake excess or toxic levels of vitamin D, you may experience constipation, in addition to other digestive problems, loss of appetite, and muscle weakness.
Vitamin D deficiency is linked to headaches because it can affect inflammation and how your neurons work. You can increase your vitamin D levels with supplements, vitamin-D rich foods, and sunlight. Taking supplements can reduce how often your headaches occur.
Signs and symptoms of too much vitamin D
Nausea. Vomiting. Weakness. Headache.
But how do you flush vitamin D out of your system – and can you even do that? Yes, by ensuring you consume plenty of water. This will encourage urination, allowing your body to shed the excess vitamin D and calcium more quickly. Prescription diuretics like furosemide can also be helpful.
If you take too much supplemental or prescription vitamin D, it can lead to vitamin D toxicity. The main complication of this is moderate to severe hypercalcemia, which can cause symptoms like vomiting, increased thirst and frequent urination.
Vitamin D deficiency has been linked to many neurological disorders, such as Alzheimer's disease, dementia, Parkinson's disease, and multiple sclerosis. A lack of vitamin D has also been linked to depression, anxiety, and other mental health disorders.