Table 2.

Zinc deficiency following bariatric surgery

Author(s), year, and country	Study design and duration	Sample size and age	Type of BS	Intervention and period	Weight reduction since surgery	Effectiveness of zinc supplementation	Zinc dose	% zinc absorption
Ruz, Carrasco [21] USA	RCT; August 2004 and December 2006	n = 67 18–55 years; F: 67	RYGBP	Group A: received the standard vitamin and mineral supplement Group B: received the improved vitamin and mineral supplement Before, 6, 12, and 18 months	27.9% 6 mo 35.2% 18 mo	Zinc deficiency significantly developed in both groups. By MO 6 90.9 ± 6 19.0 µg/dl; p < 0.001	Standard: 7.5 mg/d Improved: 15 mg/d	Decreased significantly from 32.3 to 13.6% at 6 mo after RYGBP and to 21% at 18 mo after surgery
Papamargaritis [22] UK	Prospective cohort; 36 months	n = 437 patients; 82% F; age: 45.9 ± 11.2 years	RYGB/SG/AGB 57%/20%/23%, respectively	Stander multivitamin supplementation; 3, 6, 12, 18, 24, and 36 months	NR	Zinc deficiency ranged from 7 to 15% 3 MO: 18 (9.1%) 6 MO: 24 (13.8%) 12 MO: 18 (14.8%) 18 MO: 5 (12.5%) 36 MO: 1 (2.3%)	Zinc 15 mg/d	NR
Balsa [23] Spain	Cohort; 5 years	n = 141 patients, 52 (RYGB) and 89 (BPD)	RYGB BPD	Stander multivitamin supplementation; followed up at 3, 6, 12, 24, 36, 48, and 60 months	NR	Zinc level significantly decreased in the BPD group (p < 0.0001) In RYGB zinc deficiency significantly lower at 48 and 60 months (15.4% and 21.2%, respectively)	8 mg/d	NR
Salle [24] France	Cohort; June 2005 and 2009	n = 324 patients 48 M and 276 F; RYGB (n = 266) or SG (n = 33) or DS (n = 25); age: 29–65 years	RYGB SG DS	Multivitamin supplementation; follow-up 6,12 and 24	% of weight loss 6 MO: 25.2 ± 6.6 12 MO: 32.5 ± 8.8 24 MO: 33.4 ± 11.1	% of zinc deficiency patients. 6 MO: 35.6%; 12 MO: 42.5%; 24 MO: 34.8%; zinc deficiency was present in 42.5% of patients at M12 and more frequent after DS (91.7%) at M12	15 mg/d	NR
Billeter, Probst [25] USA	Prospective cohort; 2 years	20 patients 50% male Age: 18–70 years	RYGB	Multivitamin supplementation; follow-up, 3, 6, 12, and 24	NR	Zinc decreased significantly over 24 months 13.9 ± 0.5 to 10.8 ± 0.5. mol/l	NR	NR
[26] USA	Cohort December 2002 to June 2003	n = 100 patients	LRYGB	Multivitamin supplementation Follow-up, 3, 6, 12	NR	Zinc deficiency 3 MO 23%; 6 MO 23%; 12 MO 36%	NR	NR
Rojas, Carrasco [27] Chile	RCT 2004–2008	n = 63 F; mean age: 36.9 ± 9.2 years	RYGB	Group A: received the standard vitamin and mineral supplement Group B: received the “improved vitamin and mineral supplement” Group C: extra zinc supplement; baseline and 6 months after RYGBP	NR	Plasma zinc concentration increased in all groups after 6 months of surgery: 8.6 ± 23.2 p = 0.007	A: 7.5 mg/d B:15 mg/d C: 25 mg/d	NR
Gobato, Seixas Chaves [28] Brazil	Cohort	n = 36 patients Age: 18 to 65, 75% F	RYGB	Multivitamin supplementation, baseline, and 6 months after RYGBP	The mean weight loss from baseline to 6 months after surgery was 35.34 ± 4.82%	(61.11%) patients reported zinc deficiency 6 months after surgery	7 mg/d of zinc oxide	NR
Pires, Martins [29] Brazil	Cohort	n = 22 patients; age 19–56 years	RYGB	No supplementation baseline and 6 months after RYGBP	Weight after 6 months of surgery 80.50 ± 12.60 kg	At 6 months after the RYGBP operation, the patients had decreased zinc concentration in urine compared with the initial value, and the difference was statistically significant (p < 0.05)	NR	NR
Dalcanale, Oliveira [30] Brazil	Prospective cohort; 2 years	n = 75 Age: 18–65 years; M: n = 7, F: n = 67	GBP	Multivitamin supplementation; 2 years	EWL% = 50% or above	40.5% of patients had zinc deficiency, which was significant (p = 0.008)	25 mg/d	NR
Pech, Meyer [31] Germany	Prospective, single centre, observational, 2005–2009	n = 82 patients underwent SG Age: 22–64 years; M: 48, F: 34	SG	33 patients underwent zinc supplementation 3, 6, 12, 18, and 24 months	EWL% was 54.3% after 6 months and 65.3% after 12 months	30 patients received zinc supplementation; 13.4% of participants had zinc deficiency after surgery	15 mg/d	NR
Katsogridaki, Tzovaras [32] Greece	Prospective cohort study; 2013–2015	50 patients; 14 M (28%) and 36 F (72%), age: 38.74 ± 11.87 years	LSG	6 months after surgery Multivitamin supplementation	NR	Zinc deficiency was 7% preoperative 0.70 (0.20) (p < 0.001) and ranged from 7 to 15% post-operative 0.58 (0.19) (p < 0.001) in patients receiving multivitamins and mineral supplementation post-operative, 0.11 95%CI (− 0.16–0.071)	7 mg/d	NR

²n, number; SD, standard deviation; M, male; F, female; MO, month; NR, not reported; LGBP, laparoscopic gastric bypass; LSG, laparoscopic sleeve gastrectomy; LRYGB, laparoscopic Roux-en-Y gastric bypass; LAGB, laparoscopic adjustable gastric banding; RYGB, Roux-en-Y gastric bypass; SG, sleeve gastrectomy

Summary of 12 studies