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All About Vitamin A: Recommended Intake, Sources, and Supplements

Following up on Part One, this article will focus on Vitamin A, its function, food sources, drug interactions, and government regulation of labeling. There is also some personal opinion thrown into the mix (sorry, I can't stop myself!).


Vitamin A is primarily classified as a "fat soluble" vitamin, but can also be a "water soluble" vitamin, depending if it originates from an animal source (food from animals) or a plant source (foods from plants).

So if Vitamin A is both fat soluble and water soluble, what exactly does that mean for my body? How do I tell the difference?

The label must list all of the ingredients and whether they are from animal or plant sources.

Vitamin A from an animal source is fat soluble, and is absorbed much easier and quicker than Vitamin A from a plant source. It also stays in the body longer. Vitamin A is stored in your liver and fatty tissues, and needs fat in order for the body to use it effectively.

Vitamin A from a plant source is water soluble. It can be consumed daily and will wash out of the body each day with body fluids.

  • It is not necessary, nor is it advised by most medical professionals, to consume fat soluble vitamins every day.
  • Taking mega-doses of fat soluble vitamins can cause toxicity because the dose stays in the body for a long period of time.

I remember it this way to keep from getting confused:

  • Animal fat = fat soluble Vitamin A
  • Water the plants - water soluble Vitamin A

Dietary Supplements Are Big Business

According to several National Health and Nutrition Examination Surveys (NHANES):

  • "the percentage of the U.S. population, ages 20 and over, who used at least one multivitamin/multimineral product increased from 30% in the NHANES study of 1988 to 1994.
  • It went up to 39% in the NHANES study conducted from 2003 to 2006, with use more common among women than men."

You would think that a business that big would have some kind of regulation, especially since we, as consumers, rely on the FDA to protect us regarding the safety of our foods and drugs.

Nope, we are on our own because vitamins and supplements are not considered food and they are not considered drugs, even though people take them religiously for their general good health.

Forms of Vitamin A

Vitamin A is normally measured in International Units (IU), although some labels measure it in micrograms (mcg).

Vitamin A comes in two forms: (see photos for food sources)

  1. Retinol - (a pre-formed Vitamin A)
  2. Carotenoids - (a pro-formed Vitamin A or provitamin)

Product Requirements

According to the CDC, to be considered a dietary supplement, the product must contain three or more vitamins.

But it does not have to have any minerals added to the composition.

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Most people, when they think about Vitamin A, think about their eye health. It is true that Vitamin A helps your eyes adjust to changes in light. Therapeutic doses have been shown to assist with the treatment of night blindness.

But it is also important for skin, bone and teeth growth and development, the reproductive system (producing sperm), and regulating the immune system.

Vitamin A keeps your mucous membranes moist - skin, eyes, mouth, nose, throat and lungs. It is an important antioxidant that regulates the immune system, and studies say it is important in the prevention of certain types of cancer.

Vitamin A, in the form of beta-carotene, is the best to choose. For skin, topical retinol is best.


It is very easy to get too much Vitamin A (retinol) from your supplements. But it is possible to get too little as well.

3,000 micrograms of preformed Vitamin A is more than three times the Recommended Dietary Allowance, and some publications consider this to still be safe.

However, conservative thinking says that this high dose increases the risk of hip fractures and can interfere with the benefits of Vitamin D, which often accompanies Vitamin A formulas.

Beta-carotene (preformed Vitamin A) is not considered toxic at high levels and some people believe it reduces their risk of cancer.

Smokers should avoid high doses of stand alone Vitamin A (without added vitamins and minerals) because some recent trials linked high doses with increased lung cancer risk.

Beta-carotene should not be taken as a stand alone supplement. It should always be accompanied by other supplements in a formula.

Food Sources for Carotenoids (provitamin A)


Food Sources for Retinol (pre-formed Vitamin A)


Who Regulates the Vitamin & Supplement Industry?

After extensive reading on this subject, the answer I arrived at is: No one.

The official National Institute of Health (NIH) answer is that there is no government oversight because dietary supplement manufacturers are not drug manufacturers.

The supplement companies probably enjoy that status because that means they have no one but the consumer to answer to regarding the quality of their products.

  • So therefore - in my opinion - the wolves are guarding the hen house.

Studies show that most of us take vitamins and supplements daily. I wonder how many people take them "just in case" they are not getting enough in their diet ...

In October 1994, Senator Orrin Hatch's creation of Dietary Supplement Health and Education Act of 1994 ("DSHEA") and President Bill Clinton's signing it into law, was a lot of pomp and circumstance that ended up creating yet another government agency (most likely with prime office space in Washington DC) that still sits and twiddles its thumbs, having no real job to perform and even less of a job description.

In an excerpt (i.e. gibberish) from the FDA's website which explains the latitude given to the dietary supplement companies:

  • Before 1994, dietary supplements were subject to the same regulatory requirements as were other foods. (In other words, there was very little or no regulations.)
  • This 1994 law only addressed the safety and labeling of dietary supplements.
  • Under DSHEA, each company continues to be responsible for determining that the dietary supplements it manufactures or distributes are safe. Any representations or claims made about them must have adequate evidence to show that they are not false or misleading. This is why labels are devoid of claims or cures, or even giving consumers an inkling of what the product is used for.
  • Dietary supplements do not need approval from FDA before they are marketed.
  • A company does not have to provide the FDA with their evidence that supports the safety or effectiveness of their products, except in the case of introducing a new dietary ingredient. In this case, it is required by law that it be reviewed for safety data and other information before going on the market. If the new ingredient was in our food supply or existed before October 1994, whether or not it was previously added to a supplement, it is not considered new and is a recognized food substance.

Are dietary supplements considered food?

Language On Label

A supplement cannot make a claim to affect the structure or function of the body, a claim of general well-being, or a claim of a benefit related to a classical nutrient deficiency disease.

It can claim to "support," "promote," or "help fight."

Informing Consumers

In June, 2007, the FDA published comprehensive regulations called Current Good Manufacturing Practices which focused on practices that ensure the identity, purity, quality, strength and composition of dietary supplements.

  • These "Practices" also governed what information should be on the label, an acceptable language so the average consumer could understand it, and the recommended dosages. (in other words: LABELING)

To date, most labeling is vague.

It pays to be an informed consumer and know what product you are looking for before you get to the store.

Are they drugs?

Warning: Vitamin A and Prescription Interactions


The New Law Was All About The Labels

Since this multi-billion industry is primarily a self-care industry, proper labels were deemed more necessary to address than the actual regulation of the products. A well funded government study yielded the types of information we see today on our dietary supplement labels.

Paraphrased from

  1. A dietary supplement must be labeled as a dietary supplement. (a real no-brainer)
  2. The label must give the consumer enough information to make informed decisions about products. However, the label cannot say precisely what body system the product will cure or treat. It can only use words like "help build" or "promotes good."
  3. The label must very clearly disclose the ingredients in the supplement as well as in the capsule or tablet composition (i.e. gluten free, sugar free, etc.)
  4. The label must make known the safety information - interactions, contraindications, and possible side effects and adverse reactions.
  5. The label must give understandable directions for use, including proper doses and frequency of doses.
  6. The label must have the name of the manufacturer, production location and batch numbers
  7. The label must be of a unique design so that consumers can distinguish the product from other self-help products.
  8. The label must have this disclaimer: “This statement has not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease” if the supplement bears a claim to affect the structure or function of the body (structure/function claim), a claim of general well-being, or a claim of a benefit related to a classical nutrient deficiency disease."

Symptoms of Vitamin A Deficiency

Commonly associated with malnutrition, it is rare to see a Vitamin A deficiency (xerophthalmia) in the United States.

Because Vitamin A is stored in the liver and fatty tissues, deficiency can take as long as two years to manifest in the body.

Symptoms of Deficiency:

  • Night blindness
  • Dry, rough skin
  • decreased resistance to infections
  • poor tooth development
  • slower bone growth for age group.

Best Supplements To Take With Vitamin A


Symptoms of Vitamin A Toxicity

Toxicity presents in patients more than deficiencies and some supplement formulaes have very high doses of Vitamin A which is not complemented by enough of the other vitamins and supplements in the dose.

The label must say that the majority of Vitamin A is beta-carotene.

Toxicity Symptoms

  • dry, itchy skin
  • headache
  • nausea
  • loss of appetite

High doses of Vitamin A over short periods of time can lead to dizziness, blurred vision, slower growth and possibly hip fractures. When pregnant, high doses have been associated with severe birth defects.

Function Of Foods Rich In Vitamin A

Another graphic listing food sources and the corresponding body function

Another graphic listing food sources and the corresponding body function

Dr. Oz talks about his vitamin intake

This content is accurate and true to the best of the author’s knowledge and does not substitute for diagnosis, prognosis, treatment, prescription, and/or dietary advice from a licensed health professional. Drugs, supplements, and natural remedies may have dangerous side effects. If pregnant or nursing, consult with a qualified provider on an individual basis. Seek immediate help if you are experiencing a medical emergency.

© 2014 Rachael O'Halloran


Rachael O'Halloran (author) from United States on February 09, 2015:


I agree that people do abuse supplements, either because of ignorance or wanting to see the end result ASAP. But I think for people who are "low" in a certain supplement, daily use under a doctor's care is a good thing.

I also think that sick people who find they can get the same wellness result from a supplement rather than (or in addition to) a prescription medication, that it is also a good thing.

My pet peeve is when the public is told to only buy from a "trusted source," because even with them lately, there is controversy as I mentioned in a comment on the other article.

For readers who haven't visited that article, my comment said:

There was an item in the news this week (2/8/2015) centering around GNC, Target, Walgreens, Walmart, CVS and several other stores for selling supplements.

They cited for selling them with very little or NO supplement in each capsule/tablet. There were wheat and rice fillers, mislabeling where it said it was gluten free and sugar free and other fillers were just plain garbage - scraps of broccoli, veggies, sugar, flour, etc.

The New York Times reported it here:

CNN chimed in with their report on the story:

Forbes wrote about a cease & desist letter sent to the affected retailers:

Hopefully, people will start turning back to food as a first 'go to" place after reading reports like the above.

Thank you for reading and commenting.

poetryman6969 on February 09, 2015:

A lot of experts say that for most of us, most of the time supplements are a waste of money.

I tend to believe that we should get most of our nutrients from food but I still think that some people some of the time, there might be a benefits for some supplements.

We do have to avoid a Popeye cartoonish view of supplements though. It is definitely possible to take too much. For instance, if you ate a whole polar bear liver you would probably die because there is more vitamin A in it than your liver can handle.

Rachael O'Halloran (author) from United States on November 26, 2014:


Thank you for your kind words. This series has taken on a life of its own because of the volume of information I have included in the upcoming articles. I'm trying to streamline down the word count on the ones I have in the queue because they are just too long. So I am breaking them up into smaller articles to make the reading go easier, but that also means more photos, which I try to make myself to avoid copyright infringement accusations. At the moment I have no less than 38 articles open as WIP, most of them are on different topics, plus populating 14 blogs with at least two posts weekly. I'm hopeful to get some of the vitamin articles published by the 1st week of December. Thanks for reading. :)

SherriDW on November 26, 2014:

Thank you for this hub and for taking on this series of hubs. I'm looking forward to all of the rest. I love how you have included the food sources and the supplement information together. It is also great to read about the toxicity and deficiency. It seems that the best way to self-medicate with supplements is to understand what they do and how much to use. Your information makes this possible.

Rachael O'Halloran (author) from United States on November 18, 2014:

vkwok, thanks for reading :)

Victor W. Kwok from Hawaii on November 18, 2014:

This is some very great and important info to consider. Thanks for sharing, Rachael!

muhammad abdullah javed on November 17, 2014:

You are most welcome Racheal. Expecting more reads in future.

Rachael O'Halloran (author) from United States on November 17, 2014:

m abdullah javed, I really believe that doing our homework is essential in the area of supplements because if we don't look out for ourselves, it is true that the FDA and the manufacturers will not do it for us. Thank you so much for reading, commenting and for your encouragement. I appreciate that.

Rachael O'Halloran (author) from United States on November 17, 2014:

Minnetonka Twin, We are very blessed :)

muhammad abdullah javed on November 17, 2014:

Informative and extensively worked to bring out an excellent hub about the suplements. People tend to give their best as far good health is concerned but when any sort of imbalance occur their routine gets severely disturbed. Only a fortunate few get the proper guidance as far the larger manority is concerned they simply get misleaded by one or the other way. I think your article, in this regard, provides with the excellent guidance. Thanks for the share Rachael and keep writing on such issues.

Linda Rogers from Minnesota on November 17, 2014:

Rachael-that's exactly it. I feel better taking supplements as part of my health regiment. I'm ten years cancer free and hope to stay that way. Loved hearing about your inspirational story of how supplements have kept your disease from progressing. Here's to good health. We are both very blessed.

Rachael O'Halloran (author) from United States on November 17, 2014:

vocalcoach, You are right. They work together with a healthy diet. Whether science ever proves it or not, I know I feel better. And to me, that's all that matters. :)

Thanks for reading and commenting.

Audrey Hunt from Pahrump NV on November 16, 2014:

I'm a firm believe in taking vitamin supplements along with a healthy diet. I have personally experienced a major improvement in my energy levels after starting on a strict vitamin regime.

Great hub! Audrey

Rachael O'Halloran (author) from United States on November 16, 2014:


I always use food as my first "go to" but supplements are my life-saver for certain conditions I'd rather not medicate for. I don't put any stock into negative feedback from doctors in response to my self-treatment. Yes, they'd just as soon give a prescription - all those drug reps going in and out of doctor's offices push them to write prescriptions - but it doesn't mean I have to fill it at pharmacy.

No worries about going off to left field, I spend a lot of time there. lol

Thanks for sharing your story.

Jackie Lynnley from the beautiful south on November 16, 2014:

Since our government has made it against the law for doctors to recommend vitamins or herbs etc for cancer or any illness there is no way they are going to do any of this I really fear and I think it all has to do with money in the pockets of politicians from pharmaceuticals. I honestly think we should first of all use food where we can to prevent and treat illnesses and diseases and vitamins supplements and herbs because we can't possibly fulfill that need with food. I do think doctors are starting to see patients moving ahead of them when it comes to things like this. My last visit to the doctor she asked did I still have reflux problems (I knew she was preparing to write me a prescription as I already have had one written that had so many side effects I would just as soon have the acid problem!) and I told her no, that I used ginger and I had no more acid problems. She just sort of hummed without looking at me and said well anything like that might help for awhile. What a thing to say! Like chemicals would be much better for me!

Oh well sorry didn't mean to go off in left field! lol I know what you mean though and have made my own list of several of this does that; etc.


Rachael O'Halloran (author) from United States on November 16, 2014:

Jackie Lynnley, for my pictures, I use two free programs: one called Pizap, ( and the other called Picasa 3 (chrome extension). They are very easy to use and fun to play with. You can add layers (flowers, patterns, borders, etc.) to make the pix more striking or pretty. But for this article, I opted for a more subtle look because I didn't want the pictures to dominate over the article's information.

I look forward to reading your article. Do follow through and write it. This is a very much neglected topic and needs all the attention we can give it.

If lobbyists would lobby for more important things like this instead of mundane topics the average person doesn't care about, and if Congressmen would give some diligent attention to it, we might see some changes.

There hasn't been any new laws offered since 1994 and even that "law" did nothing to help the consumer make informed decisions. All it did was cover the manufacturer's butts to make the labels politically correct with wording, ingredients, etc and made it so manufacturers didn't overstep their bounds with product "claims."