Vitamin A is a fat-soluble vitamin that is naturally present in many foods. It has several important functions in the body including the immune system, fetal development and cellular differentiation (cells reproduce). It is essential for eye health to aid in adjusting to dim lighting conditions. It is the main vitamin responsible for your spidey-senses of “night vision”


Vitamin A deficiency dates back as far as 1819, during a study with malnourished dogs. During 1912, a biochemist discovered there was an unknown substance present in milk that were not fats, proteins or carbohydrates. In 1917, researchers discovered this substance while researching the role of dietary fats. In 1920, the substance was finally referred to as vitamin A.

Health Benefits

  • Immune system function by supporting the growth and distribution of T-cells, a type of white blood cell that protects your body from infection
  • Bone formation
  • Reproduction and Fetal development- Regulates cell growth and division
  • Wound healing
  • Vision- assists with color vision and low-light vision, and also helps protect/ maintain the cornea (the outermost layer of your eye) and the conjunctiva (a thin membrane that covers the surface of your eye and inside of your eyelids)
  • Skin health- Keeps mucus membranes healthy (the lining in the nose, sinuses, and mouth). Helps maintain other surface tissues such as your skin, intestines, lungs, bladder and inner ear.


Some vitamins are not considered a single compound. What I mean by this is that there are various forms of Vitamin A including retinoids and carotenoids. There are also derivatives from these compounds such as retinyl. Sounds confusing I know. I will try to break it down to better understand the different forms to help choose the best for your needs.

Vitamin A comes from two sources. Carotenoids and retinoids. Carotenoids such as beta carotene, lycopein and lutein are plants based and retinoids such as retinol and retinal come from animal sources.

Beta Carotene, a carotenoid, is the precurser (ProVitamin) for Vitamin A. Beta carotene is a red/orange pigment found in many fresh fruits and vegetables. Once consumed, beta carotene converts to Vitamin A in the intestines and liver. The advantage of beta carotene is that the body only converts as much as it needs when needed.

Retinoid is preformed, readily used Vitamin A and includes retinOL and retinAL. It does not need conversion. The main difference of the two retinoids is the potency and how fast each works. A common retanOL used is prescription strength retinoic acid such as Retin-A.

They couldn’t just make this simple! Still with me?……

Lastly, we have synthetic, man-made version of Vitamin A derivatives known as esters found in supplement forms. These derivatives are also found from remnant retinoids. In other words, retinoids can convert into esters and esters are also found in supplement forms.There are few out there and they are named for the amino acid they are bound to.

  • Retinyl palmitate
  • Retinyl acetate
  • Retinyl linoleate

A good way to get your vitamin A is to think about eating in color. Most yellow/orange foods contain Vitamin A. You can get recommended amounts of vitamin A by eating a variety of foods, including the following:

  • Beef liver and other organ meats
  • Dairy products, which are among the major sources of vitamin A for Americans.
  • Cantaloupe
  • Carrots
  • Mango
  • Pumpkin
  • Sweet potatoes
  • Winter squash
  • Dark green, leafy vegetables
  • Broccoli

Symptoms of Deficiency

The following are some symptoms of vitamin A deficiency:

  • Eyes- Poor vision, thinning and ulceration of the cornea, loss of night vision
  • Dry hair and skin
  • Miscarriage or infertility
  • Delayed growth in children
  • Higher risk of infections: in the throat, chest, and abdomen
  • follicular hyperkeratosis (AKA keratosis pilaris) harmless, small, rough, tan or red little bumps around hair follicles

Risk Factors for Deficiency

Vitamin A deficiency can result from inadequate intake, malabsorption of fat, and/or liver disorders. A prime example is people with Irritable Bowl Disease, Ulcerative Colitis or Crohns Disease. These GI disorders have a hard time absorbing nutrients such as Vitamin A.

Common Side Effects of Vitamin A

  • Carotenodermia- Common and harmless condition affecting the color of the skin. Kids often will generally appear to have an “orange” nose.
  • Skin- cracking, itching and increased sensitivity to sunlight
  • Vision- Double vision
  • Hair loss
  • Brittle nails
  • Gum disease
  • Muscle and Joint pain
  • GI- Vomiting, nauseas, anorexia
  • Headache, dizziness,
  • Irritability, fatigue, drowsiness, changes in alertness
  • Bulging fontanelle (soft spot) in children
  • Photocarcingenicity- Retinoic acid such as topical creams has been associated with photocarcinogenicity. Which basically means it can cause skin cancer if you dont take precaution by applying sunscreen or avoiding sun exposure with use.

The Concern….

Vitamin A toxicity can occur due to high doses of preformed vitamin A retinol and esters found in some supplements. In some personal care products and supplements, vitamin A compounds and derivatives can be harmful.

Vitamin A is a fat-soluble, meaning that any amount not immediately needed by the body is absorbed and stored in fat tissue or the liver. If too much is stored, it can become toxic resulting in liver damage. In contrast, preformed vitamin A, beta-carotene is not toxic even at high levels of intake because the body only coverts when it is needed. 

Drug Interactions

  • Antacids
  • Anticoagulants
  • Antibiotics- Tetracyclines and Neomycins
  • Cholesterol-lowering medications
  • Medications Processed in the liver- Common one is Tylenol
  • Omeprazole
  • Weight loss medications

What do you use Vitamin A for? Comment below.

Leave a Reply