Side Effects of Vitamin Supplements

Vitamin supplements are available at every grocery store, mega-discount store, pharmacy, health food store, and thousands of websites on the Internet. As these vitamin supplements are considered 'natural' products, many people feel they are safe to take without the worry of side effects. Vitamin supplements do have side effects, some of which can be severe or even deadly. Below are the side effects for some of the more common vitamin and mineral supplements: Vitamin C, Calcium, Zinc, and Vitamin E.

Vitamin C: Daily Recommendations and Side Effects
Vitamin C, also known as ascorbic acid, is required by the body for the growth and repair of tissue, the absorption of iron, and the formation of collagen. It is an antioxidant and boosts the effectiveness of the immune system.

The recommended daily dosages for Vitamin C are:
Ages 0-6 months - 40 milligrams
Ages 7-12 months - 50 milligrams
Ages 1-3 years - 15 milligrams
Ages 4-8 years - 25 milligrams
Ages 9-13 years - 45 milligrams
Ages 14-18 years - 65 milligrams (girls) and 75 milligrams (boys)
Men 19 years of age or older - 90 milligrams
Women 19 years of age or older - 75 milligrams
Pregnant teens (18 years of age or younger) - 80 milligrams
Pregnant adults (19 years of age or older) - 85 milligrams
Breast feeding teens (18 years of age or younger) - 115 milligrams
Breastfeeding adults (19 years of age or older) - 120 milligrams
Smokers (adults 19 years of age or older) - 125 milligrams (men) and 110 milligrams (women)

Side effects of Vitamin C supplements include nausea, heartburn, stomach cramps, and headache.

Vitamin C is not stored in the human body, which makes a toxic build-up very rare. It is possible to take too much Vitamin C in one day, especially when using products such as Vitamin C drops while suffering from a cold or flu.
Toxic levels of Vitamin C:
Ages 1-3 years - above 400 milligrams
Ages 4-8 years - above 650 milligrams
Ages 9-13 years - above 1,200 milligrams
Ages 14-18 years - above 1,800 milligrams
Ages 19 years and up - above 2,000 milligrams
The toxic amount for infants is not currently known. Only give babies the amount that is found in their normal feedings of breast milk or formula and foods.

The side effects from high doses of Vitamin C supplements include severe diarrhea, nausea, and gastritis (irritation of the stomach lining). Some individuals may experience dizziness, faintness, flushing or fatigue. Medical attention may be required after excessively high doses of Vitamin C.

Long term high-dosing of Vitamin C supplements has been connected to kidney stones. High doses of Vitamin C should not be taken by people with a history of kidney failure or those using medications that do damage to the kidneys.

People with conditions made worse by acids, such as gout and cirrhosis, should avoid taking more than the recommended daily amount of Vitamin C.

Vitamin C supplements may increase the side effects of acetaminophen (Tylenol) and antacids that contain aluminum. Vitamin C has been shown to increase the blood levels and side of effects of aspirin and decrease the blood levels of fluphenazine (Prolixin). In high doses, it reduces the effectiveness of the blood thinning medication warfarin (Coumadin, Waran). Tell your doctor you are using a Vitamin C supplement.

Calcium: Daily Recommendations and Side Effects
Calcium is well known for building strong bones and fighting osteoporosis. It is also used by the body to regulate muscle contractions, nerve impulses, and hormone secretion.

The recommended daily dosages for calcium are:
Ages 0-6 months - 210 milligrams
Ages 7-12 months - 270 milligrams
Ages 1-3 years - 500 milligrams
Ages 4-8 years - 800 milligrams
Ages 9-18 years - 1,300 milligrams
Ages 19-50 years - 1,000 milligrams
Age 51 years or above - 1,200 milligrams

Side effects of calcium supplements include nausea, decreased appetite, constipation, vomiting, dry mouth, thirst, and increased urination.

The toxic level of calcium for all ages above infancy is 2,500 milligrams. At this amount or above, calcium supplements can produce serious side effects, such as severe nausea and vomiting, dehydration, confusion, delirium, muscle weakness, neuromuscular disturbances, coma and death. It is important to seek medical attention after taking an overdose of calcium supplements.

Calcium is a common ingredient in antacids. Combining antacids with calcium supplements is the most common reason for calcium toxicity. Be sure to calculate your calcium intake from antacids and adjust your calcium supplementation to stay within the recommended daily values.

Calcium supplements can interfere with the absorption of medications such as tetracycline antibiotics and thyroid medications. Calcium supplements can increase the risk of abnormal heartbeats in people taking digitalis. The risk of calcium overdose from calcium supplements is increased in people using thiazide diuretics. Before starting any medication, tell your doctor or pharmacist if you are using a calcium supplement.

Zinc: Daily Recommendations and Side Effects
Zinc has become popular in the last few years as a way to fight colds and flu, showing up on store shelves in the form of lozenges and nasal sprays. Zinc has immune system enhancing properties and is required by every cell in the body for proper functioning.

The recommended daily dosages for zinc are:
Ages 0-6 months - 2 milligrams
Ages 7-12 months - 3 milligrams
Ages 1-3 years - 3 milligrams
Ages 4-8 years - 5 milligrams
Ages 9-13 years - 8 milligrams
Ages 14-18 years - 11 milligrams (boys) and 9 milligrams (girls)
Men 19 years of age or older - 11 milligrams
Women 19 years of age or older - 8 milligrams
Pregnant teens (18 years of age or younger) - 12 milligrams
Pregnant adults (19 years of age or older) - 11 milligrams
Breastfeeding teens (18 years of age or younger) - 13 milligrams
Breastfeeding adults (19 years of age or older) - 12 milligrams

Side effects of zinc supplements include abdominal pain, nausea, vomiting and diarrhea. When using zinc lozenges, side effects can include taste distortion, unpleasant taste and stomach cramping. The side effects of nasal zinc products include burning, tingling, a loss of smell (possibly irreversible), and increased respiratory infections (especially in children).

Daily zinc intakes of 60 milligrams (combing both zinc supplements and food sources of zinc) in adults have been shown to cause copper deficiency. Copper is another mineral that is essential to the proper functioning of the body. For this reason, the limits where zinc is considered dangerous have been set lower as a protection.

Total zinc intake (zinc supplements and food) should not exceed:
Ages 0-6 months - 4 milligrams
Ages 7-12 months - 5 milligrams
Ages 1-3 years - 7 milligrams
Ages 4-8 years - 12 milligrams
Ages 9-13 years - 23 milligrams
Ages 14-18 years - 34 milligrams
Ages 19 years and up - 40 milligrams

Doses of 50 milligrams to 150 milligrams per day will cause gastrointestinal distress. Doses of 225 milligrams to 450 milligrams usually cause vomiting.

High doses of zinc supplements can cause liver inflammation, liver failure, gastric erosion and intestinal bleeding. Large doses of zinc supplements have also been linked to conditions that affect the blood cells, causing a low white blood cell count and red blood cells that cannot absorb iron.

Daily use of zinc supplements can reduce your levels of good HDL cholesterol. Zinc supplements should be used with caution when trying to control your cholesterol, especially when using cholesterol medication. Be sure to inform your doctor you are using a zinc supplement.

Zinc supplements can change the way your body excretes insulin and need to be used with caution when taking medication for diabetes. Tell your doctor you are using a zinc supplement.

Zinc supplements can reduce the effectiveness of some antibiotics, including erythromycin, tetracycline, and fluoroquinolone (Cipro).

Vitamin E: Daily Recommendations and Side Effects
Vitamin E is an antioxidant. It is used by the body to promote immune system health and help cells function properly.

The recommended daily dosages for Vitamin E are:
Ages 0-6 months - 4 milligrams (6 IU)
Ages 7-12 months - 5 milligrams (7.5 IU)
Ages 1-3 years - 6 milligrams (9 IU)
Ages 4-8 years - 7 milligrams (10.5 IU)
Ages 9-13 years - 11 milligrams (16.5 IU)
Ages 14 years and up - 15 milligrams (22.5 IU)
Women who are breastfeeding - 19 milligrams (28.5 IU)

Side effects of Vitamin E include headache, nausea, flatulence, bloating, diarrhea, blurred vision, fatigue, and weakness.

Toxic levels of Vitamin E:
Ages 1-3 years - above 200 milligrams (300 IU)
Ages 4-8 years - above 300 milligrams (450 IU)
Ages 9-13 years - above 600 milligrams (900 IU)
Ages 14-18 years - above 800 milligrams (1,200 IU)
Ages 19 years and up - above 1,000 milligrams (1,500 IU)
The toxic amount for infants is not currently known. Only give babies the amount that is found in their normal feedings of breast milk or formula and foods.

Toxic level side effects include the side effects listed above, plus a risk of hemorrhaging due to an inability of the blood to clot properly.

Vitamin E supplements may increase the risk of bleeding and should be used with caution by people taking blood thinners (warfarin, sold as Coumadin, Waran), antiplatelet drugs (Plavix, Persantine) or anti-inflammatory drugs, including aspirin and ibuprofen (Advil). Tell your doctor or pharmacist you are using a Vitamin E supplement.

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Sources:
Linus Pauling Institute's Micronutrient Information Center, Oregon State University:
Vitamin E
Vitamin C
Calcium
Zinc

National Institutes of Health National Library of Medicine - Medline Plus:
Vitamin C
Zinc

Drugs.com:
Vitamin E
Vitamin C
Cacium

Nutritional Supplement Educational Centre:
Vitamin C
Vitamin E
Calcium
Zinc