Articles about vitamins, supplements, nutrition, minerals, antioxidants

Google

Web this site
Article Categories

Home
Acupuncture
Allergy
Aromatherapy
Arthritis
Ayurveda
Back Pain
Cancer
Diabetes
Dental Care
Hair Loss
Herbal Medicine
Homeopathy
Hypnotherapy
Meditation
Magnetic Therapy
Massage
Natural/Home Remedies
Natural Pain Relief
Nutrition
Skin Care
Stress
Supplements/ Vitamins
Weight Loss
Yoga

Home > Vitamins

All About Vitamin A



Vitamins are essential for good health and well being. They are defined as any group of substances required in small quantities for healthy growth and development. They cannot be manufactured in the body so they are therefore vital constituents of the diet.

There are two types of vitamins according to whether they are soluble in water or fat. Vitamin A (Retinol) is a fat soluble vitamin and this is not excreted from the body in the urine so excessive intake can have a negative effect on health. Vitamin A is present in animal origin foods eg. liver, milk and egg yolk. It is formed in the body from the pigment Beta-carotene which is present in certain vegetables eg. carrots, cabbage and lettuce.

Vitamin A has a number of roles in the body. It is necessary for normal cell division and growth. It is important for maintenance of mucous membranes of the repiratory, digestive and urinary tracts. Retinol is a pale yellow solid which dissolves easily in oil and fat and it is essential for good eye sight, particularly vision in dim light as well as having an important role in normal development of the embryo. It can be produced synthetically and therefore used to enrich margarines.

The best source of retinal is liver and a small amount 3g meets the bodys daily requirements. 700mcg per day is a sufficient amount per adult which can also be derived from the beta carotene foods eg. 2oz raw carrots.

Deficiency of Vitamin A causes stunted growth, night blindness and drying up of mucous membranes which increases the risk of infection. A continued lack of Vitamin A can lead to worsening of vision.

Why not check out our reccomended nutrition guide at http://www.nutritional-supplement-guides.com/nut-ebook.html

John Gibb is the owner of Nutrition guides, a website offering free nutrition advice and a quality nutrition book with special offers and bonuses for newsletter subscribers.

http://www.nutritional-supplement-guides.com/ Dedicated to optimising health.

Article Source: http://EzineArticles.com/?expert=John_Gibb





Related Links:


Vitamins: The Basics from Food and Sunshine

Vitamins and Supplements for Menopause

Vitamins To Clear Skin

Are There Really Vitamins For Hair Loss?

Can Vitamins Help to Cure Acne?

After WLS: Tough Pill To Swallow - Tips for Taking Vitamins

Vitamins Are Essential

Eating Healthy, Being Healthy

Vitamins For Healthy Hair

Increasing Your Vitamin Intake Can Decrease Your Chances Of ...

What are vitamins?

an organic substance that acts as a coenzyme and/or regulator of metabolic processes. There are 13 known vitamins, most of which are present in foods or supplements; some are produced within the body. Vitamins are crucial for many bodily functions including a healthy immune response.
An essential low molecular weight organic compound required in trace amounts for normal growth and metabolic processes. They usually serve as components of coenzyme systems. For humans, vitamin A, the B series, C, D1 and D2, E and K are required. Deficiencies of one or more vitamins in the nutrient supply result in deficiency diseases.