Inositol deficiency diet and lithium effects.
OBJECTIVE
A major hypothesis explaining the therapeutic effect of lithium (Li) in mania is depletion of inositol via inhibition of inositol monophosphatase. However, inositol is also present in the diet. Restriction of dietary inositol could theoretically enhance the effects of Li.


METHODS
We used dietary inositol restriction in animal studies and also devised a palatable diet for humans that is 90% free of inositol.


RESULTS
Dietary inositol restriction significantly augmented the inositol-reducing effect of Li in rat frontal cortex. Li reduced inositol levels by 4.7%, inositol-deficient diet by 5.1%, and Li plus inositol-deficient diet by 10.8%. However, feeding with the inositol-deficient diet did not enhance the behavioral effect of Li in the Li-pilocarpine seizure model. Fifteen patients participated in an open clinical study of the inositol-deficient diet: six rapid cycling bipolar patients responding inadequately to Li or valproate in different phases of illness; two Li-treated bipolar outpatients with residual symptomatology, and seven inpatient Li-treated bipolar patients in non-responding acute mania. The diet had a major effect in reducing the severity of affective disorder in 10 of the patients within the first 7-14 days of treatment.


CONCLUSIONS
These results suggest that dietary inositol restriction may be useful in some bipolar patients, but controlled replication is necessary.
Stanley Research Center, Ministry of Health, Beer-Sheba Mental Health Center, Beer-Sheva, Israel.
Alona
A
Shaldubina
Ziva
Z
Stahl
Mariala
M
Furszpan
William T
WT
Regenold
Joseph
J
Shapiro
Robert H
RH
Belmaker
Yuly
Y
Bersudsky
D000328:Adult; D000818:Animals; D014150:Antipsychotic Agents / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D001714:Bipolar Disorder / Q000178:diet therapy* / Q000188:drug therapy / Q000378:metabolism; D004032:Diet; D005260:Female; D005625:Frontal Lobe / Q000187:drug effects* / Q000378:metabolism; D006801:Humans; D007294:Inositol / Q000172:deficiency* / Q000378:metabolism; D016651:Lithium Carbonate / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D051381:Rats; D017207:Rats, Sprague-Dawley; D012720:Severity of Illness Index
D014150:Antipsychotic Agents; D016651:Lithium Carbonate; D007294:Inositol