Investigating the prevalence of nutritional abnormalities in patients prior to and following bariatric surgery.

AIMS: Bariatric surgery remains an effective treatment for the condition of obesity. However it predisposes patients to nutritional deficiencies and related complications. The aim of this study was to identify nutritional abnormalities, weight loss, adherence to supplements, and presence of gastrointestinal symptoms in a cohort of bariatric surgical patients. METHODS: An analysis of the electronic medical records of patients attending a multidisciplinary private clinic in Sydney, Australia from August 2020 to August 2021 was conducted. Data on anthropometric measures, nutritional indices, adherence to supplements and gastrointestinal symptoms preoperatively and then at ≤6 months, 1 and 2 years or more postoperatively were collected. RESULTS: A total of 231 patients were included in the study. The majority of patients were female (76.2%), with a sleeve gastrectomy (78.8%). Average preoperative BMI was 43.4 ± 7.1 kg/m2 . Weight loss ≥2 years postsurgery was 33.5 ± 12.4 kg. The most common abnormalities preoperatively were: C-reactive protein (47.7%), vitamin D (39%), B12 (31%), parathyroid hormone (27.6%) and ferritin (12.7%). Vitamin B12 (23.2%), parathyroid hormone (23%), vitamin D (17.7%) and ferritin (15.9%) remained common abnormalities postoperatively. Adherence to multivitamins was 90% in the first year following surgery, declining to 77% at ≥2 years. Gastrointestinal symptoms were predominantly present in the initial stages following surgery, manifesting thiamin deficiency in 6.5% of patients. CONCLUSIONS: Despite achieving durable weight loss, nutritional and related abnormalities remain an ongoing challenge for bariatric surgery. Adherence to nutrient supplements, gastrointestinal symptoms and related complications are important considerations in addressing the problem.

Changes in Anthropometric Measures, Nutritional Indices and Gastrointestinal Symptoms Following One Anastomosis Gastric Bypass (OAGB) Compared with Roux-en-y Gastric Bypass (RYGB).

PURPOSE: Bariatric surgery is an effective treatment for obesity with new procedures emerging. However, despite comparable weight loss and improvements in metabolic outcomes, research on nutritional and gastrointestinal symptoms remains limited. Here we compare clinical data on weight, nutritional disorders and gastrointestinal symptoms of patients before and following one anastomosis gastric bypass (OAGB) and Roux-en-Y gastric Bypass (RYGB). MATERIALS AND METHODS: In this retrospective study, data on anthropometry, nutritional indices, dietary intake and gastrointestinal symptoms were retrieved in cohorts of patients up to 2 years following OAGB and RYGB. RESULTS: Seventy-three patients had either a RYGB (28) or an OAGB (45), with 71% seeking these as a revisional procedure. Significant and higher weight loss was observed in the OAGB cohort at 1 year (%TWL 33.0 ± 8.5 vs. 26.6 ± 12.4), albeit comparable at 2 years postoperatively (%TWL 29.0 ± 11.1 vs. 34.1 ± 11.2). Disorders such as vitamin D, active B12, folate, homocystein (Hcy) and hyperparathyroidism were present following both surgeries. Levels of vitamin D, ferritin and total protein significantly worsened over time. Gastrointestinal symptoms of diarrhoea, steatorrhoea and reflux were higher in the OAGB cohort while the RYGB cohort reported more dumping syndrome (DS). CONCLUSION: Significant and similar weight loss results are seen following both OAGB and RYGB. Nutritional disorders were common in both cohorts and increased over time. However, the OAGB patients reported more gastrointestinal side effects, which may contribute to poor quality of life and nutritional consequences. Prospective and longer-term studies investigating the nutritional and gastrointestinal health of patients undergoing OAGB is recommended.

The Relationship Between Bariatric Surgery and Diet Quality: a Systematic Review.

BACKGROUND: Bariatric surgery is currently the most effective treatment for morbid obesity. These procedures change the gastrointestinal system with the aim of reducing dietary intake. Improving diet quality is essential in maintaining nutritional health and achieving long-term benefits from the surgery. The aim of this systematic review was to examine the relationship between bariatric surgery and diet quality at least 1 year after surgery. METHODS: A systematic search of five databases was conducted. Studies were included that reported diet quality, eating pattern, or quality of eating in adult patients who had undergone laparoscopic-adjusted gastric banding (LAGB), Roux-en-Y gastric bypass (RYGB), and sleeve gastrectomy (SG) procedures. Data was extracted to determine the relationship between having had bariatric surgery and subsequent diet quality. RESULTS: A total of 34 study articles (described in 36 articles) met the inclusion criteria. The majority of studies were observational in nature and showed a reduction in energy intake following surgery, as well as inadequate intakes of micronutrients and protein, and an excessive intake of fats. There was evidence of nutrient imbalances, suboptimal compliance with multivitamin and mineral supplementation, and limited follow-up of patients. CONCLUSION: The current evidence base suggests that despite being effective in reducing energy intake, bariatric surgery can result in unbalanced diets, inadequate micronutrient and protein intakes, and excessive intakes of fats. In combination with suboptimal adherence to multivitamin and mineral supplementation, this may contribute to nutritional deficiencies and weight regain. There is a need for high-quality nutrition studies, to identify optimal dietary compositions following bariatric surgery.

Effects of vegetable consumption on weight loss: a review of the evidence with implications for design of randomized controlled trials.

Vegetable consumption is a key strategy in many weight loss programs but establishing the evidence that vegetable consumption per se assists with weight loss may be difficult. Creating a dietary energy deficit involves the whole diet, so research on the effects of vegetables may need to consider the whole-dietary model. The aims of this review were to examine the evidence on whether a higher vegetable consumption resulted in greater weight loss in overweight adults (compared to lower intakes) in view of a critique study designs with respect to their potential impact on outcomes. Using the PubMed search engine, a systematic review of randomized controlled trials (RCTs) published in the period 1988 to 2011 was conducted. Of the 16 RCTs scrutinized, five reported greater weight loss, nine no difference, one showed weight gain, and one reported a positive association between weight loss and high vegetable consumption. Trials which showed beneficial effects compared a healthy high vegetable diet with a control diet based on usual consumption patterns, and/or included behavioral support and counseling. On face value, the evidence reviewed appeared inconclusive but closer examination of study designs exposed important implications for RCTs that examine effects of foods on weight loss.

Relative validity of a diet history interview in an intervention trial manipulating dietary fat in the management of Type II diabetes mellitus.

BACKGROUND: This study assesses the relative validity of a diet history interview in 56 free-living individuals with Type II diabetes mellitus. METHODS: The diet history interview was compared to a 3-day food record in a 1-year dietary intervention trial. The plausibility of energy intake data was examined throughout the trial. Paired data were compared for differences and the presence of systematic error was determined by Bland Altman analysis. Changes in accuracy and responsiveness were assessed over time. RESULTS: The proportion of underreporters was larger in the diet history at baseline. Underrecording with the food record was more common in subjects with BMIs > 30 kg/m(2). There was no difference between paired dietary data from the two methods; however, data on fatty acids failed to correlate. These correlations improved when outliers were removed. There was no evidence of a relationship between bias and mean intake of dietary variables. Accuracy of diet history measurement did not change during the trial for energy or macronutrients, but data on protein and monounsaturated fat were both affected by BMI. The diet history was more responsive than the food record to changes in monounsaturated fatty acid intake after 3 months, but this changed at the end of the trial. CONCLUSION: The diet history provided good estimates of energy and macronutrient intakes in a sample group with Type II diabetes mellitus. However, energy intake data revealed a high prevalence of underreporting especially in people with higher BMIs.