6 Negative Side Effects of Too Much Super B Complex

What Are the Side Effects of Super B Complex?
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Since your body can't produce B vitamins, you must get them through diet or supplements. Of the 170 million Americans taking dietary supplements, 24 percent take a vitamin B complex, according to the annual survey by the Council for Responsible Nutrition. If you feel that you need more vitamin B, consider whether super B-complex vitamins are right for you.


What Is Super B Complex?

There are several brands of super B-complex vitamins in supplement form on the market. Super B complex with C contains a combination of eight essential B vitamins — thiamine, riboflavin, biotin, niacin, vitamin B6, vitamin B12, folic acid and pantothenic acid — and the antioxidant vitamin C.

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Read More: The Best Form of B-Complex Vitamin

Know How Much to Take

Since vitamin B is made up of various extracts, each having a unique structure and function, the amounts required vary with each person. According to Michigan Medicine at the University of Michigan, taking the predetermined amounts contained in many B-complex supplements makes little sense. Although you might take advantage of the super B-complex benefits, an alternate solution is to create your own personalized supplement to ensure you're getting the right B vitamins in the right amount.


According to Healthline, skin rashes, swollen tongue, numbness in hands and feet, fatigue, weakness, anemia, confusion, nausea, abdominal cramps, flatulence or diarrhea can indicate deficiency of any of the B vitamins. Check with your doctor to confirm that you actually need a supplement before taking super B complex.

Super B Complex Side Effects

Because B vitamins occur naturally in your diet, super B complex side effects are rare. Any side effects are likely caused by additives in the supplement, which can cause an allergic reaction or digestive tract disorders. According to Brain Power, these might include black stool, infrequent or incomplete bowel movements, diarrhea and abdominal pain. These negative reactions often disappear as the body adjusts to the vitamins. Try to purchase additive-free supplements.


Be Careful Not to Overdose

It's unlikely that you'll get too much vitamin B from your diet because B-complex vitamins are water soluble, meaning that excess is excreted in your urine, often causing a bright yellow color change. However, it's possible to overdose on vitamin B supplements, especially if you're taking other herbal or vitamin nutritional supplements that also contain vitamin B.



According to the Office of Dietary Supplements, if you take very high levels of vitamin B supplements for a year or longer, you might encounter loss of control of bodily movements due to severe nerve damage. Other symptoms of excessive intake of vitamin B include excessive thirst, skin conditions, sensitivity to sunlight, nausea and heartburn. These symptoms usually disappear when the amount of vitamin is decreased to normal.

Read More: Vitamin Toxicity Symptoms


Avoid Interaction With Medications

A potentially problematic interaction can occur when super B-complex vitamins are taken with other drugs or medicines. The Office of Dietary Supplements warns that vitamin B supplements taken with cycloserine, an antibiotic for treating tuberculosis, could cause the drug to worsen seizures and damage nerve cells. Certain anti-seizure drugs may react with the folic acid in super B complex, reducing the drug's effectiveness. Drugs taken for asthma and other lung conditions could reduce vitamin B levels and cause seizures. WebMD recommends not taking with antacids or antibiotics any brand of vitamin B complex that contains iron. Super B complex may also cause false lab test results.


Are Supplements Necessary?

The average healthy person can get required B vitamins relatively easily by eating foods high in vitamin B, such as milk, eggs, cheese, meat, fish, shellfish, dark green vegetables, beans, nuts, wheat germ and yeast. Certain conditions may influence your decision to take advantage of super B-complex benefits. If you're age 50 or older, you may need more vitamin B, and Healthline reports that vitamin B may increase testosterone levels, which naturally decrease with age in men. For pregnant people, vitamin B may help fetal development, ease nausea and lower the risk of preeclampsia. Health conditions, such as celiac disease, HIV, alcohol dependence, Crohn's disease or kidney conditions, can prevent your body from absorbing vitamin B properly. If you eat a vegetarian diet, you may be lacking one or more of the B vitamins.

Read More: How Does Vitamin B Complex Help Your Body?



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