This post covers all you need to know about vitamin A, including causes of deficiency (it’s quite common these days when people restrict dietary fats), best food sources, supplementation guidelines and benefits.
Vitamin A is an essential nutrient we can’t do without but it’s often overlooked by both health practitioners and patients which may result in a deficiency that is not corrected sometimes for a long period of time.
In fact many unexplained and difficult to resolve chronic health problems are associated with low levels of this vitamin.
Needless to say any deficiency related health problems will not be resolved unless the diet is corrected and appropriate supplementation is undertaken.
Vitamin A deficiency mini case study
As an example, I worked with a client who was a vegetarian and was given an iron supplement by her doctor to correct iron deficiency anaemia. She didn’t respond to iron supplementation (her levels didn’t go up at all) plus she was constipated whilst taking iron (this is a common side effect of iron supplementation).
She came to me looking for answers and by doing basic blood tests we discovered that she was also deficient in zinc, low in vitamin D, plus her protein markers were low and she displayed typical symptoms of low vitamin A related to vision, skin, hair and nail changes (see what they are below), in addition her diet was also inadequate.
It’s known that vitamin A deficiency may exacerbate iron deficiency anaemia, therefore I prescribed high doses of quality cod liver oil, vitamin D, zinc plus a bioavailable iron supplement, and advised her to also eat foods rich in vitamin A such as eggs, butter and orange-coloured vegetables with addition of olive oil (she was a vegetarian so her food options were limited).
Studies show that the combination of supplemental vitamin A and iron seems to reduce anaemia more effectively than either supplemental iron or vitamin A alone (1).
Other studies in rats have shown that iron deficiency alters plasma and liver levels of vitamin A (2). After around 5 weeks of supplementation she was feeling much better and had more energy. Blood tests showed that her iron levels went back to normal after just two months.
She was then able to maintain good levels by consuming iron and vitamin A rich foods, vitamin D, sufficient amount of quality protein, and taking a multivitamin on a regular basis.
Despite the importance of this vitamin for health, it is also one of the most controversial nutrients due to its potential toxicity if consumed and/or supplemented in excessive quantities. Being a fat soluble vitamin, too much of vitamin A in the diet and especially from multiple supplements, can accumulate in the body, leading to potential harm.
More likely however, low fat, calorie restricted diets and avoiding vitamin A rich animal foods, place many people at risk of having dangerously low levels.