TABLE 1.

The recommended components of routine pre-surgery nutritional assessment¹

Parameters	Measurements and evaluation strategies
Medical background	Anamnesis should include comorbidities (e.g., diabetes mellitus, hypertension, sleep apnea), gastrointestinal symptoms, psychological background, substance use, sleep hygiene
Weight-management history	Family history of obesity Onset of obesity Previous weight-loss regimens
Eating patterns	Number and types of meals per day Liquid intake Eating patterns (e.g., vegetarian, lactose free, gluten free) Dysregulated eating Eating pace Dietary restrictions including avoidance of certain food groups and/or aversion of certain foods Evaluation of nutrients intake (energy, macronutrients and micronutrients intake by 24-h recall or food diary)
Eating pathologies	Eating disorders assessment by multidisciplinary team using structured diagnostic interviews and/or self-reported validated questionnaires as needed
Anthropometric measurements	Weight Height Waist circumference Consider body-composition assessment by DXA or BIA if available
Nutritional status	Screening for nutritional deficiencies Tests should include at least: serum PTH, serum calcium, 25(OH)D, serum albumin, vitamin B-12, folate, blood cell count, iron, ferritin, transferrin, total iron binding capacity, electrolytes Consider more extensive testing in patients undergoing malabsorptive procedures or with specific findings and at-risk patients (i.e., vitamins A, K, and E; thiamin; 24-h urine calcium excretion; zinc; and copper)
Supplementation use	Type and dose of supplementation intake Ability to swallow pills
Skeletal status	DXA at spine and hip prior to malabsorptive surgeries (e.g., RYGB and BPD/BPD-DS) and in patients at higher risk2
Oral health	General oral hygiene Numbers of masticatory functional unities and chewing ability If needed, consider referring to dentist for consultation
Physical activity habits	Type, intensity, and frequency of exercise performance per week by specific questionnaires or objective measurements (e.g., pedometer) Possible limitations and barriers to perform exercise Mobility level by subjective assessment Physical function assessment by validated methods such as the sit-to-stand test, hand grip, the 6-min walk test, or 12-min walk-to-run test
Bariatric surgery knowledge	General knowledge of nutrition Knowledge of surgical options and the optional side effects of the surgeries Knowledge of the needed eating techniques and lifestyle habits Knowledge of the risks of nutritional deficiencies, their consequences, and the high importance of adherence to supplementation regime following BS Knowledge of the needed follow-up regime It is recommended to use BS nutritional knowledge questionnaires if available
Surgery expectations	All the following should be determined if they are realistic: Weight goal expectations Expectations regarding the improvements in comorbidities Expectations regarding the improvements in other life components

¹BIA, bioelectrical impedance analysis; BPD, biliopancreatic diversion; BPD-DS, biliopancreatic diversion with duodenal switch; BS, bariatric surgery; PTH, parathyroid hormone; RYGB, Roux-en-Y gastric bypass; 25(OH)D, 25-hydroxyvitamin D.

²Women aged ≥65 y, men aged ≥70 y, and younger patients who have conditions associated with bone loss or low bone mass.