For several years now, research has shown that a healthy and correct diet can be a valuable support at prevention of numerous diseaseseven serious ones. Identifying which substances, associated with a given disease, can be ingested through food provides an opportunity to adopt a effective but non-invasive prevention strategy, and manage their diet more consciously, depending on their state of health.
A recent study, for example, showed that a high intake of vitamin A through food helps reduce the risk of developing diabetic retinopathya serious eye disease that can affect those with diabetes and can, in some cases, lead to blindness.
Vitamin A and diabetic retinopathy
La vitamin A plays a essential role for retinal function and the vision processas it takes part in the mechanism that enables converting light stimuli into nerve impulseswhich are then transmitted to the brain that transforms them into images.
La vitamin A, or retinolis a substance that our organism is unable to produce itself, and therefore has to take in through the foods that are rich in them, such as eggs, milk and dairy products, carotenoid-rich fruit and vegetables (carrots, apricots, berries and tomatoes).
Our organism is capable of taking vitamin A in two ways:
- directly in the form of retinol, which is stored in the liver and then be released into the bloodstream so as to maintain adequate concentration to perform its functions;
- from carotenoids, which are transformed into retinol within the intestine. The retinol thus obtained is also stored in the liver.
La diabetic retinopathy is a microvascular pathology that severely impairs retinal functionand is one of the most serious and frequent complications of diabetes. According to some studies, precisely Vitamin A deficiency could be one of the risk factors which exposes some diabetics to the onset of this serious eye disease. In the case of diabetes, hyperglycaemia causes the liver to release less retinol (or vitamin A) into the blood than it shouldwith negative consequences for the health of the eye. In particular:
- the limited amount of retinol available directly compromises the functionality of the retina;
- retinol is also able to reduce insulin resistance and thus help maintain blood glucose at normal levels. In retinol deficiencyTherefore, the body finds it harder to control blood glucose levelsand the consequent hyperglycaemia causes ainflammation of retinal blood vessels which, in the long run, results in retinopathy.
Diet and Prevention
In a recent study comparing the diets of diabetics with retinopathy and diabetics without the eye disease, it was found that diabetics not suffering from diabetic retinopathy followed a diet much richer in vitamin Awhich may have compensated for the liver's poor ability to release retinol into the bloodstream, typical of diabetes. Further studies on the subject will be needed, but it already seems clear that, in the case of diabetes, a diet particularly rich in foods containing vitamin Atogether with the recruitment of drugs needed to maintain stable blood glucose levelsmay be useful to maintain the eye health and to protect against the risk of developing diabetic retinopathy.
Source
Dr. Carmelo Chines
Direttore responsabile
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