Are You Overdosing On Vitamins?

Vitamin and mineral deficiencies can lead a host of heath complications, and maintaining a well-balanced diet can ensure that you’re getting everything your body needs.

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Some people, however, like to boost their vitamin-and-mineral-intake by taking supplements. While there is nothing wrong with meeting your daily nutrient requirements with supplements, taking too many tablets can lead to negative consequences. An excessive build-up of nutrients in the body may have its own side effects; some may be temporary while others may have some seriously debilitating effects.

While some vitamins, such as the water soluble vitamins B and C, are generally harmless even in excess quantities (they are removed from the body via urine production), other vitamins and minerals can become toxic in larger doses. With regards to the water soluble vitamins, research has concluded that some of the variants of these vitamins can be harmful in excess quantities.

Vitamin B-6, B-3 and Vitamin C

An excess of Vitamin B-6 (more than 400mg daily) can cause problems in walking and numbness in the hands and mouth, a vitamin B-3 overdose can cause liver damage and abnormal gastric ulceration, and a vitamin C overdose can lead to diarrhea and stomach aches.


Never take iron supplements unless advised to do so by a physician after tests have revealed an iron deficiency.  Iron is one of the few minerals we cannot eliminate (except through blood loss), and accumulations in the body can quickly rise to toxic levels. Iron is an oxidizing agent that can increase the risk of cancer and heart disease.

Vitamin A

Doses of over 10,000 IU (International Units) daily can lead to hair loss, diarrhea, dry skin, nausea and headaches. An overdose of vitamin A also increases the risk of birth defects.

Vitamin E

Having equal to or more than 1000 IU of vitamin E daily can cause excessive bleeding, hypertension, weariness and fatigue, and a slow immune system response. Vitamin E supplements are usually not required since the body receives enough of this vitamin through the daily diet.

Vitamin D

Having equal to or more than 10,000 IU of vitamin D daily can lead to adverse reactions in both children and adults. A vitamin D overdose in children causes nausea, diarrhea, dizziness, loss of appetite, weakness and fatigue, calcium deposits in the kidneys, a higher calcium percentage in the blood and frequent urination. Adults who overdose on vitamin D might suffer from kidney stone formation, high cholesterol levels, high blood pressure problems and calcium deposits.


The consequences of iodine deficiencies are well known, but did you know that having equal to or more than 2 mg of iodine daily can shut down your thyroid gland? Apart from impairing the functioning of the thyroid gland, an iodine overdose can also lead to dry skin, dry hair, weight gain, vomiting, rashes, mouth sores, head ache, trouble in breathing, heavy menstrual cycles, constipation, swollen salivary glands and a metallic taste in the mouth.


Doses of more than 25 mg a day can cause fatigue, weight loss, constipation, headache, zinc deficiencies,copper deficiencies, and damage to the pancreas, liver and heart muscle.


More than 2000 mg of calcium daily can lead to poor absorption and utilization of zinc, iron and magnesium, damaged kidney functioning, lethargy and fatigue, and calcium deposits in tissues.


Doses of more than 75 mg daily can cause vomiting, fluctuating cholesterol levels, anemia, stomach pain, abdominal bleeding, impaired immune response, nausea, premature births and stillbirth.


Doses in excess of 750 mcg daily can cause hair loss, tooth decay, loss of nails, yellow skin, weakness, diabetes, skin lesions and a low immune system.

The takeaway? Yes, it is possible to overdose on some vitamin or mineral supplements, and taking too much of certain ones (too much iron or vitamin A, for example) on a daily basis can lead to health problems. Consult your physician, and keep your vitamin-taking to a minimum. Try to get most of your vitamins and minerals from foods you eat to avoid these harmful side effects.