Vitamin A — A Number One Vitamin
It’s found mainly in the form of fatty acid esters such as retinyl acetate, and only in animals. This is true even though we tend to associate it with carrots, a vegetable. Fruits and vegetables contain beta-carotene, Vitamin A’s precursor.Good sources of Vitamin A include cod liver oil, liver, and dairy foods including eggs. Red fruits and veggies such as carrots contain the beta carotene you can use to make Vitamin A.Vitamin A is commonly associated with good vision, and that’s true. Loss of night vision is a sign of a Vitamin A deficiency. However, it has many other important functions.Perhaps the biggest one is that it stimulates the production of human growth hormones. HGH levels decline as we age, so that decline is closely associated with all the symptoms we call getting old: wrinkles, loss of muscle, fat gain, fatigue, balding and hair graying or whitening. Researchers believe it improves levels of HGH inside cells, and with IGF-binding protein 3 which is needed for the production of HGH.It’s also necessary for our cells to reproduce properly. That again strikes to the very bottom line of aging. If our cells can’t reproduce themselves, our organs and bodies don’t function properly and grow weaker. It’s vital to a strong immune system which protects both from outside infections of bacteria and viruses — and from inside cells gone cancerous. Dr. Ervin Epstein, Jr at the University of California in San Francisco found that a applying a cream of a Vitamin A derivative helped prevent mice exposed to UV radiation from developing basal cell carcinoma, the most common type of skin cancer.Vitamin A deficiency decreases resistance to infections. Your cells that line your lungs lose their ability to remove disease-causing microorganisms. This obviously makes you more vulnerable to influenza as well as colds and pneumonia.Vitamin A may also help your thyroid gland function properly. It decreases gland size and increased conversion of T4 to T3. T3 is the form of thyroid hormone that the body can use. Therefore, Vitamin A is critical to your body’s metabolism and immunity.Studies have shown that you can take too much Vitamin A, and high levels it can increase your triglycerides and become toxic. Don’t take any more than 25,000 IU — and that much only for a short time if you have a critical problem.Ordinarily, people who eat dairy foods and vegetables containing beta carotene don’t need to take more than 7,000 to 10,000 IU of Vitamin A per day.
