Vit A

Regarding supplementation the best readable source that I have found is "Lifestyle after Cancer" by oncologist Professor Robert Thomas.He states that "Vitamin A is a fat soluble essential vitamin found in fish and dairy foods in the form of  a retinol.It can also be ingested in fruits and vegetables that contain carotenoid provitamins beto-carotene which is then metabolised to Vitamin A." So the response would be if you have a healthy diet and as long as you have no deficiency in this particular vitamin what would be the benefit of supplementation?The author cites some lab studies on mice and how Vit A supplementation inhibited growth of prostate cancer cells but similar studies on men showed no such effect.Other studies on humans indicated some dangers of over supplementation and overdosing causing a higher incidence of lung and prostate cancer.

The author does however deal with the potential benefits of supplementation such as omega 3 fatty acids being high in A,E and D,probiotics for gut health,calcium and Vit D and polyphenols.The importance of Vit D testing and supplementation and the use of it with Vit K and zinc is fairly well recognised I suggest.In addition Vit B complex may be beneficial.Robert Thomas does say that with Vit A supplementation you may be wasting your money and without adequate testing overdosing might lead to the development of other cancers.The book is well worth a read-available on Amazon.

Best wishes

John