Deficiencies in micronutrients in morbidly obese patients are frequently diagnosed. Due to a limited diet for certain micronutrients, a great number of patients already develop these deficiencies prior to a bariatric procedure .It has long been thought that deficiencies mostly occurred in procedures with a malabsorptive component, like the R-Y gastric bypass or the biliopancreatic diversion, only.
The risk for developing deficiencies after non-bypass bariatric surgery like the sleeve gastrectomy was considered low and patients were often not even tested for deficiencies. However, because of the resection of the fundus, a number of micronutrients like iron and vitamin B12 are less likely to be absorbed, and the low risk status for developing deficiencies can be questioned.
There is no doubt that in practice the levels of nutritional deficiencies after sleeve gastrectomy are higher than those reported in the literature, research done by Capoccia et al. showed that following laparoscopic sleeve gastrectomy a significant proportion of patients developed vitamin and mineral deficiencies this include B12 , folate, iron, calcium and vitamin D . Other study report an iron deficiency in 43% of the patients who had received the same procedure. In addition, anaemia was seen in 26% of patients and significantly low B12, folate, iron and vitamin D levels.
Recently published studies highlighted the importance of monitoring and supplementation after sleeve gastrectomy as it found that at four years post-op 28.6% of participants had an iron deficiency, 12.5% folate deficiency, 15% had a B12 deficiency and 86% had a vitamin D deficiency. all of these values were much lower than within the first 1-2 years post op, so deficiencies are a very common occurrence.
As We Know the sleeve gastrectomy is the number one operation in the world at the moment and the most common complications at the moment are due to deficiencies as a result of the procedure. Some patients who have undergone a sleeve gastrectomy are told they do not need supplementation, which is untrue, multivitamin supplements are uniformly prescribed to minimize eventual deficiencies. These supplements are usually maintained long time, even during the whole life after malabsorptive techniques, while these are maintained at least during 6-12 months after restrictive procedures. Given that sleeve gastrectomy does not alter intestinal absorption, the supplements are possibly unnecessary after 1 year, once the patient can take an adequate diet.
There are a lot of things we do not know about nutritional deficiencies after sleeve gastrectomy, we need to increase awareness of this problem by reporting the actual levels of nutritional deficiencies in the published literature And also more research needs to be carried out.