Dietary modification of Parkinson's disease.
To investigate the efficacy of a low-protein diet suitable for long-term use, and to observe the effect in a double-blind manner of re-introducing large neutral amino acids or an inactive placebo amino acid, eight patients with 'on-off' phenomenon were given a low-protein diet suitable for long-term use, and then the diet was supplemented with large neutral amino acids (LNAA) or placebo in a double-blind crossover trial. Five patients had improved Parkinsonian disability on a low-protein diet compared to normal diet. On supplementing the diet with LNAA or placebo, three subjects' Parkinson's disease was significantly better on placebo and there was a trend towards improvement on placebo noticed subjectively by seven patients; however, there was no overall significant difference in disability measured by mobility diaries. Thus, we have been unable to show that the improvement on a low-protein diet is due to a reduction in LNAA, rather than a placebo effect, possibly due to the paucity of subjects; however, the patients' identification of the LNAA supplement suggests that it is a genuine effect.
Croxson
S
S
Leicester Royal Infirmary, UK.
Johnson
B
B
Millac
P
P
Pye
I
I
D000368:Aged; D000596:Amino Acids / Q000008:administration & dosage; D004044:Dietary Proteins / Q000008:administration & dosage*; D004311:Double-Blind Method; D006801:Humans; D008297:Male; D008875:Middle Aged; D010300:Parkinson Disease / Q000178:diet therapy*; D013997:Time Factors
D000596:Amino Acids; D004044:Dietary Proteins