MedlinePlus states that vitamin D is a fat-soluble vitamin that helps in the absorption of calcium. This vitamin also plays a crucial in maintaining the levels of phosphorous and calcium in the bloodstream. Vitamin D is also found abundantly in foods such as such as cheese, margarine, cream, oysters, butter and fortified milk.
In many cases, people consume high amounts of this vitamin, whether from foods or supplements. Consuming high amounts of vitamin D is known to have a detrimental effect on the functioning of the body.
Some Dangers of Vitamin D Overdose
Calcium Deposits in Vital Organs
Medlineplus states that the recommended daily intake of vitamin D for adults, whether male or female, is around 5mcg for adults who are less than 50 years of age. For those who are older than 50 years of age, the recommended daily intake of vitamin D is 10 mcg each day. Merckmanuels.com states that in some cases, although rare, people exceed the limit of 1250 mcg of vitamin D. This results in the presence of high amounts of vitamin D in the blood, thereby resulting in the accumulation of calcium in the soft tissues of the organs such as heart and lungs. This is known to hamper the functioning of these vital organs.
Kidney Stones
In his book Integrative Medicine, author and health expert David Rakel states that although vitamin D deficiency may trigger kidney stones, an excess of this vitamin in the bloodstream may have a similar effect as well.
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He points out that this effect is due to the increase in absorption of calcium by the kidneys, leading to high amounts of oxalate that trigger kidney stones.
Muscle Weakness
Consuming high amounts of vitamin D is also known to have a negative effect on muscle tissue. Changes in the levels of calcium in the blood play a crucial role in muscle contractions inside the muscle fibres. If you consume high amounts of vitamin D, it will be present in greater concentrations in the bloodstream, thereby causing a condition known as hypercalcemia. Hypercalcemia is a condition associated with muscle twitching as well as weakness. This condition has a negative impact on the skeletal muscles as well as the muscles of the cardiovascular system. Therefore, consuming high amounts of this vitamin may result in irregular heartbeat.
Hypertension
If this vitamin has been consumed for long periods of time in high doses, its negative effects can last for several months after reducing the dosage.
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High blood pressure along with fever and gastrointestinal problems are known to be common problems that occur at a later stage of vitamin D overdose.
Other Effects
The University of Michigan Health System states that although rare, negative effects such as seizures, blindness, deafness, high blood cholesterol and death may occur as a result of vitamin D overdose. Individuals suffering from inflammatory conditions such as hyperparathyroidism and other inflammatory conditions should avoid consuming high doses of vitamin D as they are more likely to suffer from these extreme side effects than those who do not suffer from these conditions.