Over the Counter Vitamins, Risks & Benefits

Written by Sky Taylor, Diet Bites

Health Studies Related to OTC Vitamins

Recently, a health study was noted in the news involving over the counter multi-vitamins and men. The study indicated that taking a daily vitamin lowered health risks in men by almost ten percent.

The issue with such studies is that generally one cluster of individuals are monitored over an established period of time. In some studies, individuals might be closely matched; in others - it's a matter of throwing everyone together in one tank.

And almost-always, they end up with conflicting results. Some that were performed almost a decade ago indicated a higher risk of cancer in some individuals. So now we have a study which is indicating benefits - in comparison to another study which is indicating risks.

The Facts: Do we really need these ongoing studies?

We really only need to use our good sense. In the old world, a multi-vitamin may have been greatly beneficial in combating certain health issues such as scurvy. But in today's world, if we eat a well-rounded diet built with the official American Food Pyramid, we should be receiving all of the important vitamins and minerals required by the human body for good health.

There are situations where a multi can be of benefit to certain individuals. The risk groups include:

Pregnant and nursing moms.

The elderly and the young who aren't getting a healthy diet, as well as any individual who isn't getting a healthy diet.

Individuals with certain health conditions, or who may be going through a particular illness. Refer to your doctor when in doubt.

Side Effects of OTC Vitamins

Many individuals may experience pain in the abdominal region after taking a multi-vitamin. Personally speaking, this is the case for me; in addition I get very nauseated at my stomach - whether taken on an empty or full stomach. At times, I've felt like I'm going to spit-up blood.

Discomfort felt in the abdominal regions of the body is just one side effect commonly felt by many individuals. On that note, let's take a look at vitamins and the symptoms of toxicity. Why do such? Because if you'll look at the label of your multi-vitamin, you'll see that many contain more than 100% of the daily requirements. Some of these can build up within the body over time - as they are stored.

And if you're getting a balanced daily diet, why should your body require 100% or more of a particular vitamin? If you feel that you're in a high risk group or that a daily multi will benefit your health, ask your doctor if you really need to be taking one. If they brush off the question and answer a generic 'yes' then ask them about the impact that daily supplement will have on your body when values exceed 100%.

Which Vitamins are Stored in the Body?

Take note that Vitamins A, B12, and D are stored in the liver in significant amounts. Vitamins E and K are also stored by the body.

Vitamin C

It is one of the OTC's that we have in our own medicine cabinet as it is great for boosting immunity, particularly useful during the cold and flu season. However, even this vitamin comes with side effects when too much is consumed. These include: diarrhea and the formation of uric acid kidney stones in some individuals. The upper level intake level (maximum) is set at 2000 mg daily.

For many vitamins and minerals, a build up can occur in the body resulting in toxicity issues which is extremely important in regards to the upper intake levels per day.

Vitamin Toxicity Side Effects & Symptoms

Vitamin A, Stored in the Liver

Dry, itchy skin, brittle nails, changes in vision, bone pain, muscle pain, joint pain, menstrual issues, loss of hair, depression, schizophrenia, anemia, liver inflammation and damage, disruption of growth in children and an increased risk of death.

One large carrot contains about 600 g. Let's add a slice of pumpkin pie for an additional 600 g, a slice of braised beef liver for 6421 g and a cup of raw spinach for about 140 g. If we add a multi-vitamin which contains 100% of the daily recommended intake (900 g for healthy adults), our body will be storing quite a lot of Vitamin A. The upper level intake (UL/day) is set at 3000 g.


Hypercalcemia which is a medical term for elevated blood calcium levels; this condition can trigger soft tissue calcification when occurring simultaneously when phosphorous levels are low.


The individual may experience pain in the abdomen, nausea, cramping and diarrhea, vomiting and liver damage. If overage is extreme, the following may occur: schizophrenia, hypertension, pain in joints, body fatigue, stuttering, headaches and at times severe, hyperactivity and depression.


General ills tend to be confined to the digestive system: stomach ulcers, nausea, vomiting, and abdominal cramping.


Nervous system disorders, abdominal and intestinal upset, irritability, insomnia, and general fatigue.


Abdominal pain, nausea, vomiting, weak pulse, and even coma. When intake is extreme, it can trigger a goiter forming, a side effect that is generally associated with iodine deficiency.


Associated with supplements, not from natural food sources: iron poisoning, vomiting, dizziness, weight loss, headaches, skin discoloration; the skin may turn bronze or hold a grayish tint. In addition, an excess of iron may contribute or trigger heart disease, certain cancers and rheumatoid arthritis.


Abdominal cramping, diarrhea, weakness, fatigue, and drowsiness.


Manganese madness which includes these side effects: irritability, unpredictability often associated with violence, and hallucinations.

Pantothenic Acid, Vitamin B5

Mild diarrhea.


Diarrhea, nausea, vomiting, gastric disturbances, abdominal pain and spasms.

Potassium Toxicity Symptoms

Diarrhea, nausea, vomiting, gastric disturbances, abdominal pain, abdominal spasms, irregular heartbeat, muscle weakness, fatigue, including death.


Fatigue, skin disorders, dizziness, nausea, vomiting, anxiety and hair loss.

B1, Thiamin

The individual may feel irritable, fatigued having poor memory, loss of appetite and disturbances in sleep. Weight loss, abdominal pain and muscle weakness may be present. Extreme cases may lead to congestive heart failure.

Vitamin B3, Niacin Toxicity

Skin infections, generalized weakness in the body, muscle weakness, digestive issues including a lack or decrease of appetite, irritability, headache, and memory difficulties. The upper level intake per day is set at 35.0 mg.

Vitamin B6, Pyridoxine

Imbalances involving the nervous system, as well as issues related to the skin: dermatitis, eczema pernicious anemia. There may also be the following symptoms present: malaise, fatigue, convulsions and seizures. The UL intake is 100 mg daily.

Vitamin D, Stored in the Liver

A decrease of loss of appetite, stomach nausea, vomiting, increase in blood pressure, kidney ailments, and fatigue. The upper intake level is set at 50 g.

Vitamin E

If obtained from natural foods, no symptoms will arise. However, with supplements it's a much different story with reactions including: intestinal and abdominal cramps, diarrhea, double vision, muscle weakness and fatigue. The upper intake level is set at 1000 mg.

Vitamin K

The same applies to K; no side effects associated with natural foods but with supplements the following risks apply:  jaundice, hemolytic anemia and the excretion of glutathione from the body. Glutathione is an internally produced antioxidant.


Generally a metallic, bitter taste in the mouth will occur along with nausea, stomach pain, cramps, and bloody diarrhea.

Vitamins, Required Daily Intake Quick Reference

Note that men, women, young children, lactating and pregnant women may require varying amounts and this table serves as a quick reference for healthy adults.

Vitamin, Mineral


As Contained in Many Multi-Vitamin Supplements

A 700 micrograms for women
900 micrograms for men


C 75 milligrams for women
90 milligrams for men


Calcium 1000 mg


Copper 900 micrograms


Floride 3 milligrams for men
4 milligrams for women


Folate 400 micrograms


Iodine 150 micrograms


Iron 8 - 18 milligrams


Iron Note: While men require about 8 milligrams daily, young women may require as much as 18 milligrams; those over 50 years of age require about 8 milligrams daily.
Magnesium 300 - 420 milligrams depending upon age, gender


Manganese 2.3 milligrams for men
1.8 milligrams for women


Phosphorus 700 milligrams


Potassium 4.7 grams


Selenium 55 micrograms


Sodium 2400 milligrams (about 1 teaspoon)


B1, Thiamin 1.2 milligrams for men
1.1 milligram for women


B2, Riboflavin 1.1 milligrams for women
1.3 milligrams for males


B3, Niacin 14 milligrams for females
6 milligrams for males


B6 1.2 milligrams for females
1.3 milligrams for males


B12 2.4 micrograms


D 5 micrograms


E 15 milligrams


K 90 micrograms for females
120 micrograms for males


Zinc 8 milligrams for women
11 milligrams for males


Vitamin Index


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