Several previous investigators have reported an incidence of
folic acid deficiency following
gastric bypass surgery of up to 38%. Failure to encounter any
folic acid deficiencies in our postoperative patients led us to discontinue follow-up
folate studies for several years. However, due to repeated references to this deficiency in the literature, we re-instituted
folate studies as part of the routine follow-up of our patients. Preoperative serum
folate levels were obtained in 1,067 patients and preexisting deficiencies found in 63, an incidence of 6%. Of the 588
folate levels determined 1 to 10 years following
gastric bypass, only six were less than 3.0 ng/di, an incidence of 1%. All patients were instructed preoperatively and postoperatively to take multivitamin/
mineral supplements after gastric restrictive surgery, and were continually educated on their importance. In a
bariatric surgery practice in which patients are instructed, reminded, encouraged and even badgered into taking postoperative
vitamin/
mineral supplements,
folate deficiency should be a rarity. In such circumstances,
folate deficiency may well act as a sensitive marker of non-compliance.