AIM: To study the effect of restrictive bariatric surgery on eating habit dependent composition of micro- and macronutrients.
Patients and Methods: 24 patients have been evaluated prospectively with a 7 day food protocol before and one year after vertical banded gastroplasty. The protocol was computerized, analysed and quantitated with a specially designed software “Prodi Helvetia” (Nutriscience GMbH, Karlsruhe, Germany), by a nutritionist. The data was compared with the reference values according to the German Society for Nutrition. Patients saw a nutritionist at least twice before surgery, immediately after surgery and 1, 3, 6 and 12 months after surgery. Every session was combined with a doctors appointment.
Results: Patients reduced their BMI from 47±1 (meanSEM) to 35±1 (p<0.001). This represents a reduction of 34±3kg or 55% of excess body weight. Eleven patients had a staple line disruption, but none had a reoperation at that time. Energy intake was reduced by 44%, from 2265±200 to 1273±124 kcal; p<0.001). Main nutrient composition changed postoperatively and was similar to a composition suggested as healthy. Carbon hydrates increased to 49±1% (vs. 45±1%; p<0.002, fat was reduced to 35±1% (vs. 39±1%; p<0.001) where as proteins were unchanged (16±1%). Interestingly, the daily intake of all micronutrients was too low already preoperatively. Specifically iodine and vitamin D were very low (33±4% and 31±12%) and didn’t change after the operation (35±12%and 35±12%). Folic acid, vitamin D and E, iodine, zinc, chlorine, fluorine intake was under 50% of the daily amount suggested by the German society of Nutrition. These substances were low already preoperatively to a similar degree, except for zinc(49±5% to 25±4%, p<0.01), folic acid (59% vs. 43%; p<0.05) and vitamin E (69% vs. 36%; p<0.05) which were even further reduced after surgery. Only the amount of iron was good preoperatively (95%). However, postoperatively iron was down to only 57% (p<0.01).
Conclusions:. Morbid obese patients have an unbalanced diet of macronutrients and a decreased intake of micronutrients. Restrictive bariatric surgery reduces calorie intake by 44% and restores a healthy relation of macronutrients but deteriorates micronutrient intake even furtherWe therefore suggest that Patients after restrictive bariatric surgery are counselled with special respect of micronutrients by their nutritionist and that vitamin substitution should last at least one year postoperatively.