Vitamins & Supplements

Wait, Multivitamins Can Be Harmful?

Did you know that Multivitamins can actually be harmful in some cases? I know, sounds a little crazy right? You are probably wondering how and when they can become harmful. So, continue reading this post I will explain. I will also include a short video if prefer to watch instead.  

Wait, Multivitamins can be Harmful?

Many people think that you can never have too many multivitamins because of the many benefits that vitamins provide. But that is not true, and dosage is actually the key important factor to pay close attention to when taking multivitamins. This is because complications can occur, overtime.  

That said, it is important to know that there is an average dosage of about once or twice daily when it come comes vitamins in general. This is because high doses of some vitamins and minerals are fine, but high amounts of others can be harmful. Additionally, you should take the time to understand your diet before asking yourself, “should I be taking a multivitamin”?


You may have heard of solubility, it refers to the ability for a given substance to dissolve in a solvent (1).  Well, vitamins have different solubility levels and the solubility properties of a vitamin determine how well they will be absorbed in your body – which directly impacts the recommended dosage amounts.

With that information above in mind, it is important to know that vitamins have solubility, and vitamin solubility is categorized into two groups:

  1. Water-Soluble: – this image is licensed under CC BY-ND (8)

Water-soluble vitamins include ascorbic acid (vitamin C), thiamin, riboflavin, niacin, vitamin B6 (pyridoxine, pyridoxal, and pyridoxamine), folacin, vitamin B12, biotin, and pantothenic acid (2). your body can expel excess amounts of these vitamins.

  1. Fat-Soluble:

Fat-soluble vitamins include vitamins A, D, E, and K. Vitamins E and K are relatively nontoxic – although your body still has no way of getting rid of them, eating higher amounts of them wont’ do anything (3). Your body has no easy way to get rid of these. So, excess amounts can accumulate over long periods of time.

However, it is important to note that not all fat-soluble vitamins are harmful – there’s just a couple we should be cautious of regarding correct dosage amounts.  More specifically, I am talking about vitamins A and D, which are two vitamins that can have toxic effects if overconsumed.


Too much vitamin A can cause the following toxic effects (4):

  • Dizziness
  •  Nausea
  •  Headaches
  • Coma
  •  Death
  • Cause Yellowish-Orange Skin (yes, I know this is not toxic, but it can be considered a negative side-effect for some)

To help you avoid these harmful effects, here is the recommend daily allowances or RDA for vitamin A, in micrograms broken down by age bracket: provides the NIH recommended  doses for Vitamin A in micrograms.
NIH recommended doses for Vitamin A (5)


There is something called vitamin D toxicity. According to the Mayo Clinic, “vitamin D toxicity, also called hypervitaminosis D, is a rare but potentially serious condition that occurs when you have excessive amounts of vitamin D in your body”(6)

Too much Vitamin D can also cause a buildup of calcium in your blood, which can cause:

  • nausea and vomiting
  • weakness
  • frequent urination.
  • Can progress to bone pain and kidney problems, such as the formation of calcium stones

To help you avoid these harmful effects, here is the recommend daily allowances or RDA for vitamin D, in micrograms broken down by age bracket: provides the NIH recommended  doses for Vitamin D in micrograms.
NIH recommended doses for Vitamin A (7)


Yes, multivitamins can be harmful in certain cases, and now you that know how and when harm can occur. Long story short, they can be harmful because large doses of the fat-soluble vitamins are difficult for your body to get rid of and they accumulate over time, causing negative side effects.  Vitamin D toxicity is not as common and is considered rare or unlikely to develop from multivitamin use. However, vitamin A toxicity is a lot more common.

That said, it is important to understand your current diet and know which vitamins you should supplement based on the foods that you usually eat. Be sure to like, share, subscribe and comment on this post. Feedback is always appreciated. You Are Strength.


  9. This Photo by Unknown Author is licensed under CC BY-ND

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