Effects of dietary counselling on protein intake and plasmatic protein profile in children with food allergy

Background: Elimination diet in children with food allergy (FA) could be responsible for inadequate dietary intake and protein imbalance.

Aim: To investigate the protein intake and plasmatic protein profile in children with FA on elimination diet.

Methods: The study included 40 children (19 boys and 21 girls, 3-36 months of age), all affected by FA on elimination diet for at least 30 days. Measurement of total protein, albumin, prealbumin, plasma nonessential to essential amino acid ratio was carried out at enrollment (t₀) and after 6 months (t₁) of dietary counselling by registered dietician.

Results: Protein intake in FA children exceeded the recommended intake, according to national dietary recommendations, as in non allergic children. The ratio between the mean value of protein intake (g/kg) in our children, assessed by a 3-day diary, and the recommended protein intake (g/kg) decreased significantly from t₀  to t₁ [t₀=1,60 (0,7-3), t₁=1,31 (0,9-2); p=0,05] after nutritional counselling. The comparison of the measurements of plasmatic protein profile [mean (min-max)] observed in the study population during the 2 times of valutation showed no significative difference (significance with p<0,05) between plasmatic total protein [t₀=6,71 g/dl (6,14-7,47), t₁=6,82 g/dl (5,88-7,52); p=0,076], albumin [t₀=4,56 g/dl (4,14-5,14), t₁=4,51 g/dl (4,11-4,81); p=0,464], prealbumin [t₀=19,08 mg/dl (13,40-24,40), t₁=18,13 mg/dl (13,70-24,50); p=0,241], However, it showed a significative difference between plasma nonessential to essential amino acid ratio (gly+ser+gln+tau/iso+leu+val+met) [t₀= 2,35 (1,20-4,33), t₁= 2,17 (1,03-3,67); p=0,031] with a significative increase of two essential aminoacids [Isoleucine: t₀=52,99 micromol/l (36,18-85,97), t₁=56,41 micromol/l (40,89-105,13); p=0,012. Valine: t₀=216,10 micromol/l (129,98-385,42), t₁=226,96 micromol/l (161,02-427,17); p=0,018] out of the four essential aminoacids considered in the ratio.

Conclusions: An unbalanced diet is a frequent feature in allergic children. This condition could be prevented and resolved by an adequate nutritional counselling. In particular, in our population the dietary intervention improved the quality of protein intake. Plasmatic non essential/essential aminoacids may be an useful marker of protein status.