Is lithium‐induced weight gain prevented by providing healthy eating advice at the commencement of lithium therapy?

Abstract

This study aimed to determine whether providing advice on healthy eating at the commencement of lithium (Li) therapy would prevent weight gain. Twenty‐five patients starting Li therapy were given healthy eating advice (treatment) and 25 patients starting Li therapy were not given dietary advice (control). After 6 months of therapy, 14/25 patients in the control group gained weight; 5/25 gained >5 kg, whereas only 9/25 of treated patients gained weight, and only 1/25 gained >5 kg. The mean weight change in patients in the control group was significantly greater (mean +1.9 kg, s.d. 5.3) than in the group of patients given dietary advice (mean −1.7 kg, s.d. 4.6, <0.05). In addition, the mean weight gain in patients who gained weight was significantly less in patients receiving dietary advice than in the control group (<0.02). Dietary advice significantly reduced the mean weight change in females (<0.05) but not in males. However, dietary advice significantly reduced the amount of weight gained by male weight gainers (P<0.01). No relationship was found between initial body weight, age, Li dose, serum Li level or other medications and weight gain. This study shows that the provision of dietary advice at the start of Li therapy has a significant effect on reducing and preventing weight gain. It is therefore recommended that all patients commencing Li therapy should receive healthy eating advice if weight gain is an unwanted side‐effect of this drug.