Table 4.

Clinical evaluation and preventive strategies for bone health in bariatric surgery

Before surgery	Prevention	Follow up
Calcium
Serum PTH	1200-1500 mg/day (after AGB, RYGB, and S.G.)	Every 6-12 month (S.G., RYGB, BPD/BPD-DS)
Serum calcium	1800-2400 mg/day (after BPD/BPD-DS) (food and supplements)**	Every 12 month (AGB) then annually
Serum 25(OH) D
DXA at spine and hip (RYGB, BPD, BPD-DS; in higher-risk patients)*		DXA at spine and hip 2 years postoperatively (all patients)
Vitamin D
Serum 25(OH) D	3000 IU D3/day (normal range 25(OH) D>30 ng/mL)***	Every 6-12 month (S.G., RYGB, BPD/BPD-DS)
Serum PTH		Every 12 month (AGB)
Protein
Serum albumin	46 g/day - women	6-12 month
	56 g/day - men	Serum albumin (S.G., RYGB, BPD/BPD-DS)
	Protein needs	12 month (AGB), then annually for all patients
	Should constitute:
	10%-35% of daily caloric intake
	Weight maintenance: 0.8-1.2 g/kg body weight/day
	Active weight loss: 1.2 g/kg body weight (BPD/DS may require 1.5-2.0 g/kg body weight/day)

*Women aged ≥65 years, men aged ≥70 years, men above age 50-69; based on the risk factor profile, and men aged 50 and older who have had an adult age fracture. **Calcium citrate is preferable over calcium carbonate because it is independent of stomach acidity absorption. Calcium should be given in divided doses (single doses should not exceed 600 mg), separated by ≥2-h intervals from iron-containing supplements. Calcium carbonate should be taken with meals, whereas calcium citrate can be taken with or without meals. ***D3 is recommended as more potent than D2, but both forms can be effective and dose-dependent. It is recommended that both D2 and D3 be taken with a meal containing fat to ensure maximum absorption. PTH: Parathyroid hormone, 25(OH) D: 25-hydroxyvitamin D, RYGB: Roux-en-Y gastric bypass, LAGB: Laparoscopic adjustable gastric band, BPD-DS: Biliopancreatic diversion with a duodenal switch, AGB: Adjustable gastric banding, DXA: Dual-energy X-ray absorptiometry, S.G.: Sleeve gastrectomy