by Dr. Lawrence Wilson
© October 2016, L.D. Wilson Consultants, Inc.
All information in this article is for educational purposes only. It is not for the diagnosis, treatment, prescription or cure of any disease or health condition.
Caution with vitamin A. If possible, do not take extra vitamin A during pregnancy. It is slightly toxic for the fetus. The amount of vitamin A in the standard nutritional balancing programs is fine, however.
I. ABOUT VITAMINS IN GENERAL
What is a vitamin? Vitamins are substances that are NOT proteins, starches, sugars or fats. Yet they are absolutely required for health.
In general, vitamins must come from our food and are not manufactured inside the body to a great extent.
Where did the word “vitamin” come from? An American scientist, Dr. Casimir Funk, early in the twentieth century, coined the term vitamin as a contraction and combination of the words vital and amines. Amines are a type of chemical. Not all vitamins are amines, but the word remains to describe these vital nutrients found in our food.
How are vitamins classified?
1. Water soluble or fat soluble. Vitamins are often classified as either water-soluble or fat-soluble. This has to do with the foods in which they are found, and the nature of the vitamin itself.
The water-soluble vitamins. These are mainly the B-complex vitamins and vitamin C.
The fat-soluble vitamins. These include vitamins A, D, E and K.
2. Letter of the alphabet. For simplicity, vitamins are assigned a letter of the alphabet. Each vitamin also has a technical name that is the name of the chemical formula.
The letter does not necessarily have to do with when it was discovered. So there are vitamins A, B, C, D, E, F, and perhaps others.
When were most vitamins discovered, and why? Most vitamins were discovered between 1850 and 1950. This was a time when biochemistry was a new science and certain analytical tools such as mass spectrometers were invented that allowed scientists to investigate and understand chemical compounds much easier.
II. VITAMIN A
One of the most important and most amazing of the vitamins is vitamin A. It is required for the immune response, and for the health of the skin and mucus membranes, which are both part of the immune system of the body.
Names. Technical names for vitamin A are retinol (an alcohol), retinal (an aldehyde) and retinoic acid.
Discovery. As early as 1817, scientists noticed that malnourished dogs developed corneal ulcers and blindness, and had a shorter lifespan, but they did not know why.
In 1912, an English biochemist, Frederick Gowland Hopkins, found unknown factors present in milk that were required to aid growth in rats. Dr. Hopkins was later awarded the Nobel Prize (in 1929) for this discovery.
In 1917, Elmer McCollum from the University of Wisconsin–Madison along with Lafayette Mendel and Thomas Burr Osborne from Yale University discovered one of these substances while researching the role of dietary fats.
In 1918, these “accessory factors” were described as “fat soluble” and in 1920, they were referred to as vitamin A.
A fat-soluble vitamin. Vitamin A is one of the fat-soluble vitamins. This means it is found usually in fatty foods. It is also best absorbed with other fatty foods such as eggs, meats and butter. It was one of the first vital nutrients to be discovered about 100 years ago, and hence it was called vitamin A.
FORMS OF VITAMIN A
1. Natural pre-formed vitamin A. This is also called retinol, and is found mainly in fish oils, including cod liver oil. It is considered the best-utilized form of vitamin A.
2. Semi-synthetic pre-formed vitamin A. This is sold as a supplement, and its technical name is retinyl palmitate. It is not quite as active or strong as the natural vitamin A, and it is slightly toxic. However, it can be used instead of the natural vitamin A from fish oils.
3. Beta-carotene. Our bodies can convert some beta-carotene to the active form of vitamin A. However, if the thyroid gland is not working well (which is very common today, especially among women), then the conversion does not occur adequately.
Unfortunately, sometimes beta-carotene is labeled as vitamin A. This is somewhat deceptive because it is not technically vitamin A. When buying vitamin A, I prefer the pre-formed vitamin A because I know it will work and does not require conversion inside the body to vitamin A.
A very yang vitamin. This is important, although it may sound esoteric. Vitamin A, because it is fat-soluble and derived mainly from animal sources, is a more yang vitamin. These are greatly needed today to balance the yin bodies.
FUNCTIONS OF VITAMIN A
Vitamin A is needed for vision, for the immune response, to strengthen the skin and mucous membranes, to regulate cell growth and bone metabolism, and is involved in hormone synthesis. However, this is just the beginning of the functions of vitamin A.
Vitamin A has other, more subtle functions, according to some authors. It helps the brain process information, for example. It is also needed in every cell for basic life functions such as respiration and energy production.
If vitamin A is low in the body, a person’s energy level will suffer, infections develop more easily, and cancer can occur more easily. Many other health problems also occur more often, from blindness to respiratory problems and others. In fact, vitamin A deficiency is still the leading cause of blindness on earth today.
Deficiency of vitamin A also causes night blindness, which is not really blindness but is difficulty seeing in the dark. It also increases the risk for cardiovascular disease, macular degeneration, cataracts, osteoporosis, diarrheal diseases and many viral illnesses.
SOURCES OF VITAMIN A
The sources of vitamin A can be divided into sources of pre-formed vitamin A and sources of beta-carotene and other carotenes, which are precursor substances that the body can often convert to true vitamin A.
Sources of pre-formed vitamin A. These are animal-based foods including some fish oils, including cod liver oil, sardine oil and salmon oil. Others are meats, eggs, cheeses, yogurt, kefir, and chicken, to some degree. Animals help convert the carotenes to the pre-formed vitamin A so that we don’t have to do it.
Sources of beta-carotene and other carotenes include most dark green, orange, red and yellow vegetables such as Swiss chard, carrots, peppers and other vegetables. Fruits have a little of the carotenes. However, fruit is too yin so I do not recommend eating much or any of it today.
Source of retinyl palmitate. This is the synthetic vitamin A. It is only found in pill form in health food stores and other markets.
REASONS WHY MOST PEOPLE ARE LOW IN VITAMIN A
Millions of people on earth are deficient in vitamin A. This causes many health problems for people, and this deficiency is largely overlooked by most doctors. The three reasons for the deficiency are:
1. Low intake. This is a major reason for low levels of vitamin A. This is particularly serious in some poorer nations where eggs, butter, fish and meat are not readily available. However, it also occurs in America and in Europe when people live on poor quality food or do not eat enough vegetables, for example.
Cooking vegetables. Carotenes are more available from cooked vegetables than from raw ones that are harder to digest.
Vegetarian or semi-vegetarian diets. These are particularly low in pre-formed vitamin A, since the main sources of vitamin A are not included in these diets, such as meats, eggs, fish and dairy products including milk, cheese, yogurt, and kefir.
Also, Most of the time, these diets are too low in iodine and other substances needed for the thyroid gland. As a result, many vegetarians cannot convert the vegetarian sources of carotenes such as red, orange and yellow vegetables and some fruits, to the active form of vitamin A. This compounds their deficiency of vitamin A and shortens their lifespans.
4. Poor digestion or absorption of vitamin A. Some people may not absorb adequate carotenes from the diet due to digestive problems.
Digestive problems that may limit the absorption of vitamin A include low digestive enzyme production and secretion, hidden infections, sensitivity to gluten, wheat or other foods, parasitic infections, and abnormal gut flora. These are all common today.
3. Impaired conversion of carotenes to the active form of vitamin A. Reasons for this are:
A. Low thyroid activity. Adequate thyroid hormonal activity is needed to convert carotenes to the active form of vitamin A. Most people today have low thyroid activity.
This is due to copper and mercury toxicity, and due to the presence of thyroid antagonists in the environment such as bromides, fluorides and chlorides. These interfere with the activity of the thyroid gland in most people.
Also, most diets are low in iodine that is needed to oppose the thyroid antagonists.
B. Other. Some people with adequate thyroid activity also seem to have difficulty converting the carotenes to the active form of vitamin A.
In one study, up to 47% of British women were unable to adequately convert beta-carotene to vitamin A. The problem may be even worse in some populations.
HOW TO INCREASE YOUR VITAMIN A INTAKE
1. Eat some animal protein daily. Sardines and butter are very good sources.
2. Eat plenty of cooked vegetables each day.
3. Take a supplement of kelp to provide plenty of iodine. Other iodine supplements may work, but kelp is a natural food and provides many other minerals along with iodine that almost everyone needs.
4. You may also take a supplement of pre-formed vitamin A, about 10,000 iu daily. Beta-carotene supplements should not be needed if you eat plenty of cooked vegetables daily. Cod liver oil also provides plenty of vitamin A
THE USE OF HIGH-DOSE VITAMIN A AS THERAPY FOR INFECTIONS AND FOR CANCER PREVENTION OR CORRECTION
Vitamin A in higher doses can be used as an infection remedy. For bladder infections, colds, influenza and many other infections, vitamin A in doses of up to 20,000 iu daily for adults can be extremely helpful.
This is often much more effective than taking vitamin C, a much more popular natural remedy, but one which is very yin so it can upset body chemistry in subtle ways.
For cancer prevention and correction, vitamin A is also helpful, perhaps because it strengthens the immune response. Adding 10,000 iu daily or more may help with this.
I always suggest that vitamin A supplements should be the pre-formed vitamin A, not beta-carotene because many people have trouble converting carotenes to the active form of vitamin A.
SYNERGY BETWEEN ZINC AND VITAMIN A
Dr. Paul Eck pointed out that a strong synergistic relationship exists between vitamin A and zinc. Both lower sodium in the mineral balancing system of the body used in nutritional balancing science.
To a limited degree, they are interchangeable, meaning that zinc and vitamin A can be substituted for one another to a limited degree, although this may sound unusual.
Also, both are needed for proper immune response and the functioning of the skin, mucous membranes, energy production, vision, hormone production and other functions. Also, both are needed for the bones, for proper growth and development, and to prevent some birth defects. Therefore, this is an interesting synergism between a vitamin and a mineral. There are other such synergisms, such as between manganese and vitamin B1.
OVERDOSING ON VITAMIN A
It is possible to overdose on vitamin A, although in my experience it is very rare. Most people are deficient, in fact. Older textbooks suggested that one would need 300,000 iu of vitamin A daily for months to overdose on it. Newer books suggest that a lower dose is too much, especially during pregnancy.
Symptoms of vitamin A overdose. Vitamin A can build up in the liver and cause symptoms such as reddening of the skin, rashes and perhaps an occasional birth defect. The solution if symptoms occur is simply to reduce one’s intake of pre-formed vitamin A.
Overdosing on carotenes does not cause vitamin A excess. The body will simply not convert the extra carotenes into vitamin A.