Nutritional follow-up in treated hyperphenylalaninemias

Hyperphenylalaninemias are currently treated by mean of diets very poor in whole animal proteins. Consequently, the therapy is constituted by special formulas, vegetables and proper glucidic and lipidic supplementations. The strict dietetic control makes the macronutrient intake closer to the recommended dietary allowances, but at risk of inadequate intake of some specific components contained only in whole animal foods. Polyunsaturated very-long chain fatty acids, carnitine, taurine and selenium are lower in treated hyperphenylalaninemic children in comparison with healthy children. A new challenge for the adequacy of the dietary intervention is represented by the management of maternal phenylketonuria, for the possible consequences on the developing tissues of the growing organism. The nutritional approach to the treatment of hyperphenylalaninemias may not only help avoiding consequences secondary to the dietary deficiencies (in particular affecting the central nervous system), but may also represent a unique opportunity for a better knowledge of the effects and consequences of specific nutrient deficiencies or supplementation, or both, on the metabolic status and body development.