Dietary supplements and bariatric surgery.

Bariatric surgery or weight loss surgery has been in practice for achieving significant weight loss in patients who have failed to achieve weight loss after pharmacological interventions. The rising cases of obesity are a triggering factor for more bariatric surgeries worldwide. Interestingly, sustained weight loss achieved post-bariatric surgery offers metabolic advantages, and patients show improved glucose and lipid metabolisms. Bariatric surgery is directly linked to higher incidences of vitamin, mineral, and trace element deficiencies, thus making patients susceptible to anemia, osteoporosis, and cardiomyopathy. Reduced nutrient absorption capacity, dietary changes, dietary restriction, and altered gastrointestinal tract morphology are some reasons for nutritional deficiency observed in post-bariatric surgery procedures. Micro-and-macronutrient deficiency observed in patients during the postoperative phase requires continuous monitoring of nutritional parameters. Therefore, adequate multivitamin and mineral supplements become essential to prevent/overcome micronutrient deficiencies. Bariatric surgery also raises the risk of small for gestational age (SGA) babies. Hence, a 12 - 24 months gap is recommended between bariatric surgery and pregnancy to achieve desired weight loss targets. The topic of this review is the impact of bariatric surgery procedures on vitamin and mineral absorption and the role of dietary supplements in maintaining a healthy nutritional balance during the postoperative phase.

Micronutrients deficiences in patients after bariatric surgery.

Bariatric surgery is an effective option for managing obesity and has gained general acceptance among patients in recent years. Generally, despite the high caloric intake, a bad nutritional habit of obese people results in the deficiency of several vitamins, minerals, and trace elements essential for body metabolism and normal physiological processes. Additionally, the current bariatric surgical approaches such as sleeve gastrectomy (SG), Roux-en-Y-gastric bypass (RYGB), laparoscopic adjustable gastric banding (LAGB), and jejunoileal bypass (JIB) can cause or exacerbate these deficiencies. Based on several reports, it appears that the various bariatric surgical procedures affect nutrient absorption differently. Being purely restrictive, LAGB and SG affect the absorption of iron, selenium, and vitamin B12, while RYGB, JIB, and biliopancreatic diversion have a more profound impact on the absorption of essential vitamins, minerals, and trace elements. Nutritional deficiencies in vitamins, minerals, and trace elements may follow bariatric surgery and are associated with clinical manifestations and diseases, including anemia, ataxia, hair loss, and Wernicke encephalopathy. The present review summarizes some of the major vitamin and micronutrient deficiencies associated with bariatric surgery, particularly those presented post-surgically. To avoid any adverse consequences of vitamin and trace element deficiency, proper monitoring and tests are recommended at any stage, from pre- to post-surgery (periodical check-up), followed by specific and individual nutritional supplementation treatments and a proper healthy diet.

Iron Deficiency in Obesity and after Bariatric Surgery.

Iron deficiency (ID) is particularly frequent in obese patients due to increased circulating levels of acute-phase reactant hepcidin and adiposity-associated inflammation. Inflammation in obese subjects is closely related to ID. It induces reduced iron absorption correlated to the inhibition of duodenal ferroportin expression, parallel to the increased concentrations of hepcidin. Obese subjects often get decreased inflammatory response after bariatric surgery, accompanied by decreased serum hepcidin and therefore improved iron absorption. Bariatric surgery can induce the mitigation or resolution of obesity-associated complications, such as hypertension, insulin resistance, diabetes mellitus, and hyperlipidemia, adjusting many parameters in the metabolism. However, gastric bypass surgery and sleeve gastrectomy can induce malabsorption and may accentuate ID. The present review explores the burden and characteristics of ID and anemia in obese patients after bariatric surgery, accounting for gastric bypass technique (Roux-en-Y gastric bypass-RYGB) and sleeve gastrectomy (SG). After bariatric surgery, obese subjects' iron status should be monitored, and they should be motivated to use adequate and recommended iron supplementation.