However, despite its long-term benefits, it is important to be aware of the risks of <\/span>post-bariatric nutritional deficiency<\/b><\/a>. Because of the anatomical and physiological changes common with bariatric procedures, patients who opt for this solution <\/span>are more likely to develop nutritional complications<\/span><\/a>. <\/span> <\/p>\n In this article, you’ll learn a little about the causes of these nutritional deficiencies after <\/span>stomach reduction<\/span><\/a>In addition, you should know which nutrients are most affected and the importance of nutritional monitoring after surgery. To find out more, contact Dr. Carlos Obregon, gastro-surgeon at <\/span>Instituto Medicina em Foco<\/span><\/a>.<\/span><\/p>\n Make an appointment with a gastro-surgeon and seek nutritional support from MEF’s multidisciplinary post-bariatric team.<\/b><\/a><\/p>\n First of all, it should be pointed out that surgical techniques in the bariatric procedure are neither purely restrictive nor disabsorptive. In the past, this concept was common (the Adjustable Gastric Band – AGB – was purely restrictive while the duodenal switch and scopinaro were dysabsorptive), but today this has changed. <\/span><\/p>\n Currently <\/span>vertical gastrectomy <\/b> (gastric sleeve) removes approximately 80% of the stomach volume. This removes an area that is extremely important in modulating appetite: the gastric fundus – the region that produces the hunger hormone ghrelin. This causes the patient to have a lower appetite. <\/span><\/p>\n O <\/span>bypass<\/b> is not a dysabsorptive surgery in most patients, at least as far as macronutrients (carbohydrates, fats and proteins) are concerned. An intestinal detour does occur, but the part destined for absorption (common loop) is much larger than in disabsorptive procedures. <\/span> <\/span><\/p>\n On the other hand <\/span>bypass patients may experience micronutrient dysabsorption<\/b> (minerals – such as iron, copper, zinc and vitamins – A, D, K, B complex). But the main mechanism of bypass weight loss is not dysabsorption, but hormonal stimulation. <\/span> Thus, bariatric surgery can lead to the development of <\/span>macro and micronutrient deficiencies after surgery<\/span><\/a> as has been shown in some studies.<\/span><\/p>\n In addition, a factor that contributes to this malnutrition is <\/span>the lack of nutritional follow-up after surgery<\/b>. According to a survey <\/span>published in <\/span>Oxford Academic<\/span><\/i>According to the study, only 29.6% of bariatric patients returned for a consultation five years after surgery. Similar data was reported in another study which showed that only 80 out of 1216 patients were receiving follow-up care in the third year. <\/span><\/p>\n Some types of bariatric surgery, such as gastric bypass, increase the risk of Small Intestine Bacterial Overgrowth (SIBO). This condition may already be present in people with obesity before the operation. <\/span><\/p>\n In a study of 378 patients, <\/span>SIBO was identified in about 15% of subjects before surgery and increased to 40% after Bypass surgery<\/b>. In addition, bacterial overgrowth compromises nutrient absorption, competing for vitamins and minerals, and its metabolites can damage the intestinal lining. This can cause deficiencies in fat-soluble vitamins (A, D and E), proteins, carbohydrates, thiamine and vitamin B12, while folate and vitamin K levels tend to rise. <\/span><\/p>\n If you have undergone bariatric surgery, contact MEF and make an appointment with Dr. Carlos Obregon.<\/span><\/p>\n Make an appointment with a gastro-surgeon in S\u00e3o Paulo and get proper post-operative nutritional care.<\/b><\/a><\/p>\n Post-surgery, it is common for some bariatric patients to report some <\/span>nutritional problems<\/span><\/a>. Take a look at the most common ones.<\/span> A <\/span>anemia is one of the most frequent deficiencies after bariatric surgery<\/b>especially in the first two years. According to the American Society of Hematology, between <\/span>33% and 49% of bariatric patients<\/b> develop anemia during this period. It is worth remembering that <\/span>up to 12% of patients already have anemia before surgery<\/b>which reinforces the importance of carrying out preoperative screening tests.<\/span><\/p>\n This <\/span>post-bariatric anemia<\/b> is usually related to <\/span>iron deficiency<\/b>caused by factors such as<\/span><\/p>\n In addition to iron <\/span>vitamin B12<\/b> can also be lacking, especially after intestinal bypass surgeries, such as bypass surgery. This vitamin depends on the duodenum and the intrinsic factor to be absorbed – structures that are altered in these procedures. A <\/span>oral or intramuscular B12 supplementation<\/b> is indicated in many cases. <\/span> <\/p>\n Another important cause of anemia is <\/span>folic acid deficiency<\/b>. It reaches from <\/span>9% to 39% of bariatric patients<\/b>also contribute to fatigue and a drop in immunity.<\/span><\/p>\n Bariatric surgery can have a direct impact on <\/span>bone health<\/b>increasing the risk of <\/span>osteoporosis, loss of bone mass and fractures<\/b>. This is because, in addition to the reduction in the mechanical load on the bones after losing weight, there is <\/span>difficulty in absorbing calcium and vitamin D<\/b>essential nutrients for maintaining a strong bone structure.<\/span><\/p>\n The main causes of this bone fragility include:<\/span><\/p>\n To prevent complications, it is essential to maintain <\/span>adequate levels of calcium and vitamin D<\/b>with targeted supplementation and regular examinations to monitor bone mineral density.<\/span><\/p>\n After bariatric surgery, it is common for the body to experience <\/span>low absorption of vitamins and minerals<\/b>, especially in procedures with intestinal detour. See the main deficits: <\/span><\/p>\n In addition to vitamins, surgery can compromise the absorption of <\/span>essential minerals<\/b> such as <\/span>zinc, magnesium, copper and selenium<\/b>. These nutrients participate in various functions in the body and their lack can affect the <\/span>nervous system, heart and intestines<\/b>. Regular check-ups are essential to detect and correct these deficiencies.<\/span><\/p>\n A <\/span>protein malnutrition<\/b> is one of the most serious complications after bariatric surgery, especially in procedures with malabsorption. After <\/span>Biliopancreatic diversion (BPD)<\/b>the incidence can reach <\/span>21% of patients<\/b>. In <\/span>gastric bypass<\/b>the risk increases when the Roux limb exceeds 150 cm, with records of up to <\/span>13% over two years<\/b>.<\/span><\/p>\n Even in more restrictive surgeries, such as the <\/span>gastric sleeve<\/b><\/a>malnutrition can occur in patients who:<\/span><\/p>\n Protein deficiency can lead to <\/span>a drop in albumin in the blood<\/b>, <\/span>edema<\/b>, <\/span>loss of strength<\/b> and increased risk of hospitalization. The evaluation of <\/span>lean body mass<\/b> and monitoring protein levels are key to detecting the problem early and adjusting diet or supplementation.<\/span><\/p>\n This is why <\/span>specialized nutritional monitoring<\/b><\/a> is essential to prevent deficiencies that can compromise the patient’s physical and emotional health. Without proper guidance, deficiencies in iron, calcium, vitamins B12, D and A are common, as well as loss of muscle mass and protein malnutrition. <\/span><\/p>\n A nutritionist with experience in post-bariatric surgery<\/b><\/a> evaluates the evolution of the diet, adapts the diet to the needs of each phase, guides supplementation and requests tests for regular monitoring. This continuous care helps to maintain a healthy weight, prevents clinical complications and improves quality of life in the long term, promoting a safe and effective process of dietary re-education. <\/span><\/p>\n![\"Contact](\"https:\/\/emfoco.med.br\/wp-content\/uploads\/2025\/08\/Entre-em-contato-com-o-Instituto-Medicina-em-foco-para-agendar-uma-consulta-com-gastrocirurgiao-em-sao-paulo-e-saber-sobre-deficiencia-nutricional-pos-bariatrica.webp\" "\\"\\"")
<\/a><\/p>\nMalnutrition after bariatric surgery: what are the factors?<\/b><\/h2>\n
Other factors that increase the risk of vitamin deficiencies in bariatric patients<\/b><\/h3>\n
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\n<\/span><\/li>\nSIBO: a factor that can occur in some bariatric patients<\/b><\/h4>\n
![\"Schedule](\"https:\/\/emfoco.med.br\/wp-content\/uploads\/2024\/11\/MEF-botao-agendar-consulta-blogpost-400-x-80-px-300x60.webp\" "\\"\\"")
<\/a><\/p>\nPost-bariatric nutritional deficiency: what problems are possible?<\/b><\/h2>\n
\n<\/span><\/p>\nAnemia<\/b><\/h3>\n
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\n<\/span><\/li>\nProblems with bone metabolism<\/b><\/h3>\n
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\n<\/span><\/li>\n<\/a><\/p>\nVitamin and mineral deficiencies<\/b><\/h3>\n
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Protein malnutrition<\/b><\/h3>\n
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\n<\/span><\/li>\nHow important is quality nutritional care in the post-operative period?<\/b><\/h4>\n