Abdominal discomfort (cramps, bloating)
Digestive upset (nausea, vomiting, diarrhea, heartburn)
Vitamin B-6: RDA – ranges from .1mg in infants to 1.7mg in adult men age 51 and over.
Too much B-6 can result in:
Changes in heart rhythm (caution is advised in taking B-6 if you have heart issues or low blood pressure)
Doses of vitamin B-6 higher than 200mg daily can cause a condition called sensory neuropathy, resulting in nerve pain or numbness, tingling, or loss of control of movement
Vitamin B-12: RDA – 1-25mcg (micrograms) depending upon age, gender, pregnancy/breastfeeding status, and current bloodstream levels.
B-12 is fairly low-risk as far as side effects. There are a few problems that can occur with excess intake:
Digestive upset (diarrhea, nausea)
Skin problems like flushing, rosacea, or pustules
IV supplementation can lead to high blood pressure
Vitamin A: RDA – 900mcg for men, 700mcg for women.
Vitamin A toxicity, while rare, can occur in two forms – short-term and long-term – depending upon how long excessive doses are taken. Symptoms of short-term (acute) vitamin A toxicity include:
Loss of skin
Brain swelling (cerebral edema)
Signs of long-term (chronic) vitamin A toxicity may include:
Dry lips and dry, cracking, itching skin
Changes in psychiatric condition
Joint and/or bone pain
Severe chronic toxicity can result in liver damage, eye damage, and excessive calcium levels. In addition, vitamin A may cause low blood pressure so caution is advised in people who are taking medication or supplements that lower blood pressure.
Vitamin E: RDA: 15mg for adult men and women.
The following may be signs of too much vitamin E:
Skin inflammation or itching
Nausea or stomach pain
Vitamin D: RDA – 600 IU (International Units) for adult men and women.
Vitamin D toxicity is rare but if it occurs, it can be serious, causing a toxic buildup of calcium in the body (hypercalcemia) which may result in:
Nausea and/or vomiting
Excessive Vitamin E can also cause frequent urination, kidney problems and general weakness.