Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

What’s So Important About Vitamin A?

  • Why Is It Called Vitamin A?
  • Why Is It Critical To Your Health?
  • What Is Beta Carotene?
  • How’s Your Night Vision?

What’s So Important About Vitamin A?

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost.

Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die.

They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them.

We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Look inside and learn more ways to improve your health….

Vitamin A & Beta Carotene cover image

 

Topic: Vitamin A & Beta Carotene

A number of difficulties can arise from a deficiency of vitamin A…. it is estimated that approximately 25% of Americans get less than half of the RDA for vitamin A in their diets. This commonly occurs in those who avoid certain fruits and veggies or when the diet is filled with processed foods that are depleted of vitamins. – Elson Haas, MD

What’s So Important About Vitamin A?

• Why Is It Called Vitamin A?

• Why Is It Critical To Your Health?

• What Is Beta Carotene?

• How’s Your Night Vision?

Look inside and learn more ways

to improve your health….

What’s So Important About Vitamin A?

In a world of interesting and innovative nutrients, the importance of vitamins seems to be lost. Here’s the 411: Vitamins are critical to our health. Without them, we become ill and die. They are essential to the normal functioning of our bodies. With few exceptions, we cannot make them. We must ingest vitamins either from food or from nutritional supplements. To obtain optimal health, regular vitamin supplementation is recommended.

Vitamin A was named vitamin A because it was the first vitamin to be officially named. (Likewise B, C, E, F, and K.1) However, it is also referred to as retinol, from retina. This is the location in the eye where vitamin A plays one of its most important roles. A fat soluble vitamin (as are D, E, F, and K), vitamin A stays in the system longer than the water soluble vitamins (B-complex and C). It needs both bile and fats to be absorbed through the intestine and into the bloodstream.

1 Vitamin F is the name traditionally given to the essential Fatty acids.

Although often associated with carrots, vitamin A does not occur in plants. True vitamin A, called  preformed vitamin A, can be obtained only from animal sources, particularly livers. (Fish liver oil is a common source for supplements.) Egg yolks, milk products, and organ meats are also rich sources. The animals that  provide us with vitamin A make it from a substance that comes from plants. Because it is found in carrots, the substance is called carotene. For example, when fish eat algae and seaweed, they are ingesting a form of carotene: beta carotene. The beta carotene is converted to vitamin A and stored in the fish’s liver. 

Likewise, when we eat plant foods containing beta carotene, we also use it to synthesize vitamin A and store it in our livers. Although other carotenes have vitamin A activity, beta carotene is the most potent provitamin A substance. It is found in a wide variety of yellow- and orange-colored fruits and vegetables. Beta carotene provides a double molecule of vitamin A activity, which can be converted to vitamin A in the upper intestine and again in the liver.

Originally, vitamin A researchers discovered that young animals receiving a diet restricted in fats became unhealthy. They didn’t thrive, their immune function faltered, and their eyes became severely inflamed and infected. These conditions were quickly relieved when they were fed butterfat or cod liver oil, foods rich in Vitamin A. 

Activities & Applications

Today, it is recognized that vitamin A levels are of major importance to eyesight, growth and tissue healing, healthy skin, immune function, antioxidant support, and the regulation of genetic processes. Functions in these areas are directly related to the vitamin’s healing applications. In Staying Healthy With Nutrition, Elson Haas, MD, identifies these three areas: 1) basic tissue and health maintenance; 2) clinical treatment for a number of problems (some of which may be vitamin A deficiency symptoms; and 3) the prevention of many illnesses and diseases.2 In this section, keep in mind that although we segregate the activities and applications, they are interdependent and interrelated.

2 This newsletter could not have been written without Elson Haas’ fabulous Staying Healthy With Nutrition. Much information about vitamin A is tricky and conflicting. Dr. Haas simplifies it. No nutrition/health library is complete without this book, published by Celestial Arts, Berkeley, CA, 2006.

Eyesight

This is the best known of vitamin A’s biological activities and healing applications. Vitamin A is needed for the formation of visual purple. This substance, formally known as rhodopsin, gives us our night vision. Night blindness is one of the first symptoms of vitamin A deficiency and occurs when there isn’t enough vitamin A to regenerate visual purple. 

Vitamin A supports eye tissue, including the health of the cornea, the eye’s covering. Any lack lowers the eyes’ resistance to irritation and infection. It has been used in the treatment of conjunctivitis, blurred vision, nearsightedness, cataracts, and glaucoma.

These interactions of vitamin A with the tissues are seen within all of its other involvements in our health.

Growth…

And tissue healing. The exact mechanism of vitamin A in this area is not understood. However, we do know that Vitamin A is involved in the development of new cells, including bone cells, promoting healthy teeth, and influencing skin and mucous membranes. It is also needed for the repair of tissues after surgery or injury, and to help protect tissues from infection. Again, we see how tissue health underlies other functions of the vitamin.

Healthy Skin

Many women are familiar with the use of Vitamin A as retinol (Retin-A) to rehabilitate sun damaged skin and with its (controversial) use in healing acne. More importantly, vitamin A helps skin cells to mature normally, inside and out.

Vitamin A provides structural integrity to our skin and our internal mucous linings, including the intestinal tract, respiratory tract, and bladder. It is easy to see how this directly relates to protection from infection and from cancer cell development. Moist, healthy mucous membranes help the body fight off infectious agents and environmental pollutants, leading directly to immune protection.

Vitamin A supplements can be punctured and the retinol applied directly to rashes, boils, and skin ulcers. It can be supplemented to support any wound healing and surgery. It may be helpful with psoriasis and with periodontal disease.

Immune Function

Vitamin A plays a part in overall immune system activity. It has been shown to optimize the function of white blood cells, to enhance recognition of food antigens (food proteins that trigger sensitivities), and also to block the activity of some viruses. Deficiencies reduce both T and B cell responses. Severe vitamin A deficiency has been shown to cause atrophy of the thymus and spleen, two organs with importance to the immune system.

Because vitamin A supports proper cell differentiation, maintains the structural integrity of cells, and secures healthy mucous membranes, it lowers cancer risk. As beta carotene, it has been shown to help lower lung cancer risk. Haas believes the evidence implies that adequate beta carotene intake will reduce the risk of many other cancers. 

On the other hand, any deficiency of these nutrients  increases the risk. In particular, low levels of vitamin A have been associated with an increased risk of cancer, including breast, cervical, lung prostate, laryngeal, and stomach cancers. Beta carotene deficiencies have been clearly demonstrated in patients with cancers of the cervix and lungs.

Antioxidation

In keeping with the information already discussed, it comes as no surprise to learn that vitamin A has antioxidant capacities. Once again, the cell membrane and tissue lining receive particular protection. Beta carotene also protects the tissues. Both vitamin A and beta carotene help protect the body from the damaging effects of smoke, chemicals, and other pollutants. They may also be helpful in preventing problems like ulcers and atherosclerosis. Haas recommends 10,000 to 20,000 IU of beta carotene daily to secure these effects.

Genetics

Each cell contains a nucleus. Genetic information (DNA) and cytoplasm are within the nucleus. Similar to the way the yolk of an egg is separated from the white by a membrane, the nuclear material is surrounded by a membrane. The nuclear membranes of many cell types carry receptors for vitamin A.

Although this research is in its infancy, it is thought that vitamin A is involved in the  regulation of genetic processes. This is a fascinating development in vitamin A technology. It will be interesting to learn how it unfolds.

And More….

Vitamin A has been used with some success to treat a variety of ailments, including asthma, plantar warts, sebaceous cysts, ulcers, premenstrual syndrome, and fibrocystic breast disease. One small study showed a reduction in pain and lumps with 150,000 IU daily used under medical supervision. (See section “Deficiency and Toxicity”.)

Beta carotene has shown promise in the area of reproductive health. Although its exact role has not been identified, the clue is in the corpus luteum, a tiny hormone-secreting body that forms in the ovary after ovulation. This structure has a higher concentration of beta carotene than any other organ in the body. In animals, increased beta carotene intake is associated with increased ovarian function and hormonal output.

Deficiency and Toxicity

There can be problems with vitamin A at both ends of the intake scale: too little and too much. Let’s begin with deficiency symptoms and then go on to vitamin A toxicity.

Not Enough….

Haas reports that approximately 25 percent of Americans get less than half of the RDA for vitamin A. This is most common among those who do not eat sufficient beta carotene containing foods. These people avoid brightly colored fruits and veggies. The three groups most commonly deficient in the vitamin are the elderly, teenagers, and alcoholics.

Night blindness or difficulty seeing at night are considered the first symptoms of vitamin A depletion. This is generally accompanied by less than healthy eye tissue. Other symptoms may include impaired vision; irritated, reddened, or dry eyes; and eyes that tire easily. Corneal ulcers may develop with severe deficiencies. Supplementing vitamin A and/or beta carotene will usually correct these problems.

A deficiency also affects the skin. Dry, bumpy skin may occur, especially on the backs of the arms. This may be accompanied by a variety of blemishes, acne, or even boils. Another symptom can be decreased skin tone and rapid skin aging. Because vitamin A protects the mucous membranes, when the vitamin is deficient, these membranes will try to protect themselves by developing a hardened exterior. In addition, the hair is affected. It may lack luster and dandruff can occur because of a lack of moisture on the scalp.

Other symptoms include fatigue, insomnia, and menstrual problems. There may also be a decrease in appetite, and some loss of smell and taste. More seriously, periodontal disease, kidney stone formation, and ear problems can develop. At the top of the vitamin A deficiency list is diminished immune response. This not only decreases our protection against infection but also against cancer. Remember, low dietary levels of vitamin A have been associated with an increased risk of many cancers, including breast, cervical, lung, stomach, laryngeal, and prostate.

Too Much

…vitamin A is the Big Bugaboo. All oil soluble vitamins are stored in the body. Vitamin A, in particular, is not easily excreted. Accumulation is only a problem when too much preformed vitamin A (retinol) is ingested. There is absolutely no danger of ingesting too much beta carotene – either as a natural supplement or as fruits and vegetables.3

3 Carotenodermia or carotenosis is yellow-orange discoloration of the skin, which generally results from drinking too much carrot juice. This is completely harmless and clears with a reduction in carotene intake.

In most individuals, vitamin A is easily tolerated with no problems. However, when too much vitamin A is stored in the body, toxicity symptoms can occur. Some of the most common symptoms include fatigue; headaches; muscle, joint and bone pain; dry, flaking skin; itching; hair loss; menstrual problems; gastrointestinal problems, including nausea and vomiting; and weight loss. More serious problems are liver enlargement, bone abnormalities (including fracture risk), and, for pregnant women, an increased risk of birth defects.

Haas refines this last complication as pregnant women taking more than 400 IU of vitamin A per pound of body weight. He suggests that pregnant women limit their intake of preformed vitamin A to no more than 10,000 IU per day with no more than 5000 IU coming from supplements.

It is important to understand that vitamin A toleration can vary widely among individuals. For example, symptoms have occurred only after 50,000 IU have been taken daily for a period of 18 to 24 months. In addition, many health practitioners have utilized vitamin A for teenage acne with levels of 300,000 to 500,000 IU per day for up to five months with no side effects. Furthermore, there have also been studies where people have ingested 1,000,000 IU per day, for five years with no toxicity whatsoever!

Recent studies have linked excess vitamin A intake with an increased risk of bone fracture. The studies involved both supplements and foods (such as cod liver oil and calves’ liver). Although the 30 year study of Scandinavian men leaves new questions in its wake, it does point to the fact that for some people, too much vitamin A in the system can lead to an increased risk of fractures. This is particularly applicable to middle-aged and older people because their bodies do not clear vitamin A from the liver as easily. Haas notes that there appears to be no risk until intake exceeds 3000 IU daily over time. In addition, natural source beta carotene (i.e., duniella) is converted to vitamin A by the body and never causes problems.

In 2000, because of the toxicity risks of vitamin A, the National Academy of Sciences set tolerable upper limit guidelines for daily vitamin A intake. (See chart.)

Upper Limits (Uls) for Vitamin A*

AgeUls

3 or younger2000 IU

4-83000 IU

9-145000 IU

14-189000 IU

19+10,000 IU

Pregnant or lactating

women 18 or under 9000 IU

Pregnant or lactating

women 19 or older10,000 IU

*These amounts reflect total daily intake of preformed vitamin A, food and supplements.

Supplementing

To prevent deficiency, the minimum amount of vitamin A needed by an adult is 3000 IU per day. About one-third of beta carotene eaten converts to vitamin A. (Remember, it is the vitamin form that is essential.) This means that one would need to eat at least 10,000 IU of beta carotene to make just adequate vitamin A. This is the approximate amount in two medium-sized carrots.

Requirements depend on body weight, so larger people need more vitamin A. Needs are also increased with illness, infection, trauma, anxiety or stress, pregnancy, lactation, alcohol use, and smoking. Plus, not every body does a good job of converting beta carotene to vitamin A. In fact, a recent study completed by the USDA showed that in half of the volunteers very little beta carotene was converted to vitamin A. The researchers believe this is probably related to genetics. (Won’t it be great when we can individualize our supplements completely using our own genetic profile?)

However, the study does point out the need for everybody to be sure to ingest enough true vitamin A daily to equal 5000 – 10,000 IU. Haas recommends an equal amount of beta carotene (or other carotenoid) for anxiety or stress. Vitamins C and E help prevent loss of stored vitamin A. (Incidentally, I take 25,000 IU of additional vitamin A once per week.)

Sidebar:

A Many Splendored Thing

Wander through the fresh produce section of your supermarket, or better yet, stroll by the stalls of your local farmers’ market. The brilliant green, orange, red, purple, and yellow colors give the fruits and vegetables some of their nutritional magic. Research reveals that produce contains hundreds, perhaps thousands, of compounds that can influence our health. Among these are the carotenes and carotenoids.

The terms carotene and carotenoid can be confusing. Carotenoids are any of a group of red, orange, and yellow fat soluble pigments. These color plants and flowers, and are also the pigments of birds (flamingos), fish (salmon), and seafood (shrimp).

Carotenes are part of the family of carotenoids. The carotene with which we are most familiar is beta carotene, the potent vitamin A precursor. Of the 600 carotenoids that have been identified, about 50 are believed to have vitamin A activity.

Besides beta carotene, carotenoids of interest are astaxanthin, lutein, lycopene, and zeaxanthin. Here, we give a brief description of each of them. For a thorough discussion of these carotenoids and beta carotene, read Nutrition News, “24 Carrots”.

Astaxanthin, a red pigment, is one of the most powerful of all antioxidant substances. There is so much to say about this topic that it will soon be published as an individual Nutrition News.

Lutein is found primarily in our eyes. It is one of two carotenoids concentrated in an area of the retina called the macula. (Yes, as in macular degeneration)  As a supplement, the pigment is extracted from marigold flowers.

Lycopene, another red pigment, is the famous nutrient of tomatoes. It protects us against two of the biggies: heart disease and cancer.

Zeaxanthin is the other carotenoid found, like lutein, in the macula.

Nutrition News „ 2008 VOL XXXII, No. 5