Table 2 Characteristics of the included studies in the meta-analysis

26

Bakalar et al. 2006

The Czech Republic

RCT

Multiple-trauma patients

I = 20

P = 20

0.4 g/kg

MT

Placebo

PN

30

FBS

8 days

I

P

− 0.4 ± 1.6

1 ± 2.3

No

− 0.71

26

Bakalar et al. 2006

The Czech Republic

RCT

Multiple-trauma patients

I = 20

P = 20

0.4 g/kg

MT

Placebo

PN

30

IS

8 days

I

P

1.7 ± 5.8

4.5 ± 4.2

Yes

− 0.55

29

Mansour et al. 2015

Iran

RCT

Patients with type 2 diabetes

I = 27

P = 26

30 g/day

MT

Placebo

Oral

50

FBS

6 weeks

I

P

–0.79 ± 1.35

–0.06 ± 1.70

No

− 0.47

29

Mansour et al. 2015

Iran

RCT

Patients with type 2 diabetes

I = 27

P = 26

30 g/day

MT

Placebo

Oral

50

Insulin

6 weeks

I

P

6.05 ± 14.1

1.67 ± 7.6

No

0.39

29

Mansour et al. 2015

Iran

RCT

Patients with type 2 diabetes

I = 27

P = 26

30 g/day

MT

Placebo

Oral

50

HbA1c

6 weeks

I

P

0.17 ± 1.32

0.24 ± 1.68

Yes

− 0.04

29

Mansour et al. 2015

Iran

RCT

Patients with type 2 diabetes

I = 27

P = 26

30 g/day

MT

Placebo

Oral

50

HOMA-IR

6 weeks

I

P

0.52 ± 6.8

0.59 ± 2.5

No

− 0.01

29

Mansour et al. 2015

Iran

RCT

Patients with type 2 diabetes

I = 27

P = 26

30 g/day

MT

Placebo

Oral

50

QUICKI

6 weeks

I

P

− 0.01 ± 0.05

− 0.01 ± 0.03

No

0

3

Dock-Nascimento et al. 2012

Brazil

RCT

Patients candidate for elective laparoscopic cholecystectomy

I = 9

P = 9

50 gr

CT

Placebo

Oral

40

FBS

24 h

I

P

19.2 ± 6

38 ± 4

YES

− 3.69

3

Dock-Nascimento et al. 2012

Brazil

RCT

Patients candidate for elective laparoscopic cholecystectomy

I = 9

P = 9

50 gr

CT

Placebo

Oral

40

Insulin

24 h

I

P

− 1.5 ± 0.8

1 ± 3.5

No

− 0.99

3

Dock-Nascimento et al. 2012

Brazil

RCT

Patients candidate for elective laparoscopic cholecystectomy

I = 9

P = 9

50 gr

CT

Placebo

Oral

40

QUICKI

24 h

I

P

0 ± 0.05

− 0.02 ± 0.02

No

0.52

27

Cui et al. 2013

China

RCT

Patients undergoing colonic cancer resection

I = 20

P = 20

0.5 g/kg

CT

Placebo

PN

55

FBS

24 h

I

P

0.77 ± 1

1.17 ± 1.1

Yes

− 0.38

27

Cui et al. 2013

China

RCT

Patients undergoing colonic cancer resection

I = 20

P = 20

0.5 g/kg

CT

Placebo

PN

55

Insulin

24 h

I

P

0.19 ± 2.5

8.81 ± 3.1

Yes

− 3.06

27

Cui et al. 2013

China

RCT

Patients undergoing colonic cancer resection

I = 20

P = 20

0.5 g/kg

CT

Placebo

PN

55

HOMA-IR

24 h

I

P

− 0.6 ± 0.6

2.3 ± 0.5

No

− 5.23

27

Cui et al. 2013

China

RCT

Patients undergoing colonic cancer resection

I = 20

P = 20

0.5 g/kg

CT

Placebo

PN

55

QUICKI

24 h

I

P

− 0.03 ± 0.2

− 0.12 ± 0.2

No

0.45

23

Singh et al. 2015

India

RCT

Patients undergoing maxillofacial surgery

I = 5

P = 5

0.77 g/kg

CT

Placebo

Oral

24

FBS

10 h

I

P

14.3 ± 15.1

35.3 ± 30.8

No

− 0.87

23

Singh et al. 2015

India

RCT

Patients undergoing maxillofacial surgery

I = 5

P = 5

0.77 g/kg

CT

Placebo

Oral

24

Insulin

10 h

I

P

− 5.8 ± 2.1

− 1.4 ± 3.6

No

− 1.5

23

Singh et al. 2015

India

RCT

Patients undergoing maxillofacial surgery

I = 5

P = 5

0.77 g/kg

CT

Placebo

Oral

24

HOMA-IR

10 h

I

P

− 1.2 ± 0.6

0.2 ± 0.8

Yes

− 1.98

25

Letellier et al. 2013

France

Cross-over

Children with Duchenne muscular dystrophy

I = 30

P = 30

0.5 g/kg

MT

Placebo

Oral

10

FBS

120 days

I

P

0 ± 0.22

0.08 ± 0.26

Yes

− 0.33

25

Letellier et al. 2013

France

Cross-over

Children with Duchenne muscular dystrophy

I = 30

P = 30

0.5 g/kg

MT

Placebo

Oral

10

Insulin

120 days

I

P

0.5 ± 0.97

0.22 ± 0.44

No

0.37

25

Letellier et al. 2013

France

Cross-over

Children with Duchenne muscular dystrophy

I = 30

P = 30

0.5 g/kg

MT

Placebo

Oral

10

HOMA-IR

120 days

I

P

0.11 ± 0.27

0.001 ± 0.22

No

0.44

24

Laviano et al. 2014

Italy

RCT

Obese patients

I = 6

P = 6

0.5 g/kg

MT

Placebo

Oral

43

FBS

28 days

I

P

− 1.6 ± 8.7

0.2 ± 8.5

No

− 0.21

24

LaviaNo et al. 2014

Italy

RCT

Obese patients

I = 6

P = 6

0.5 g/kg

MT

Placebo

Oral

43

Insulin

28 days

I

P

− 1.5 ± 4.1

0 ± 3.2

No

− 0.4

24

Laviano 2014

Italy

RCT

Obese patients

I = 6

P = 6

0.5 g/kg

MT

Placebo

Oral

43

HOMA-IR

28 days

I

P

− 0.41 ± 0.7

0.2 ± 1.2

No

− 0.62

28

Hissa et al. 2011

Brazil

RCT

Patients with coronary obstruction

I = 11

P = 11

0.19/Kg/h

CT

Placebo

PN

63

FBS

1 day

I

P

35 ± 6.5

50 ± 7

Yes

− 2.22

28

Hissa et al. 2011

Brazil

RCT

Patients with coronary obstruction

I = 11

P = 11

0.19/Kg/h

CT

Placebo

PN

63

Insulin

1 day

I

P

20 ± 38.6

40 ± 50.8

No

− 0.44

30

Lomivorotov et al. 2012

Russia

RCT

DM2 with coronary artery bypass graft surgery

I = 32

P = 32

0.4 g/kg/day

MT

Placebo

PN

60

FBS

1 day

I

P

4.9 ± 1.65

3.7 ± 1.35

No

0.8

TG

23

Singh et al. 2015

India

Experimental

Patients undergoing maxillofacial surgery

I = 5

P = 5

0.77 g/kg

CT

Placebo

Oral

24

TG

10 h

I

P

− 17.6 ± 46.5

− 14.8 ± 13.8

No

− 0.08

30

Lomivorotov et al. 2012

Russia

RCT

DM2 with coronary artery bypass graft surgery

I = 32

P = 32

0.4 g/kg/day

MT

Placebo

PN

60

TG

1

I

P

− 1 ± 1.2

− 0.95 ± 0.4

No

− 0.05

29

Mansour et al. 2015

Iran

RCT

Patients with type 2 diabetes

I = 27

P = 26

30 g/day

MT

Placebo

Oral

50

TG

6 weeks

I

P

–10.15 ± 60.1

3.69 ± 92.8

No

− 0.18

Inflammatory markers

3

Dock-Nascimento et al. 2012

Brazil

RCT

Patients candidate for elective laparoscopic cholecystectomy

I = 9

P = 9

50 gr/day

CT

Placebo

Oral

40

CRP

1 day

I

P

0.5 ± 0.5

0.7 ± 0.3

Yes

− 0.48

3

Dock-Nascimento et al. 2012

Brazil

RCT

Patients candidate for elective laparoscopic cholecystectomy

I = 9

P = 9

50 gr/day

CT

Placebo

Oral

40

IL-6

1 day

I

P

2 ± 1.5

2.2 ± 0.7

No

− 0.17

3

Dock-Nascimento et al. 2012

Brazil

RCT

Patients candidate for elective laparoscopic cholecystectomy

I = 9

P = 9

50 gr/day

CT

Placebo

Oral

40

GSH

1 day

I

P

1 ± 3

2 ± 3

No

− 0.33

31

Engel et al. 2009

Germany

RCT

Patients with cardiopulmonary bypass

I = 31

P = 20

0.5 mg/kg/day

MT

Placebo

PN

71

CRP

3 days

I

P

− 2 ± 15

8 ± 19

No

− 0.58

31

Engel et al. 2009

Germany

RCT

Patients with cardiopulmonary bypass

I = 31

P = 20

0.5 mg/kg/day

MT

Placebo

PN

71

IL-6

3 days

I

P

1 ± 2.3

0.8 ± 2.5

No

0.08

31

Engel et al. 2009

Germany

RCT

Patients with cardiopulmonary bypass

I = 31

P = 20

0.5 mg/kg/day

MT

Placebo

PN

71

IL-1

3 days

I

P

− 0.3 ± 3.1

0.3 ± 3.4

No

− 0.18

31

Engel et al. 2009

Germany

RCT

Patients with cardiopulmonary bypass

I = 31

P = 20

0.5 mg/kg/day

MT

Placebo

PN

71

TNF-a

3 days

I

P

1 ± 24

1 ± 24

No

0

31

Engel et al. 2009

Germany

RCT

Patients with cardiopulmonary bypass

I = 31

P = 20

0.5 mg/kg/day

MT

Placebo

PN

71

IL-8

3 days

I

P

1.1 ± 4.9

1 ± 2.5

No

0.02

33

Ockenga 2002

Germany

RCT

Patients with acute pancreatitis

I = 14

P = 14

0.3 g/kg/day

MT

Placebo

Oral

53

CRP

14 days

I

P

− 65 ± 60

− 21 ± 79

Yes

− 0.63

32

Cavalcante et al. 2012

Brazil

RCT

Patients with systemic inflammatory response syndrome

I = 15

P = 15

30gr/day

MT

Placebo

Oral

61

IL-6

2 days

I

P

9.49 ± 30.3

− 12.27 ± 25.5

No

0.77

32

Cavalcante et al. 2012

Brazil

RCT

Patients with systemic inflammatory response syndrome

I = 15

P = 15

30gr/day

MT

Placebo

Oral

61

IL-1

2 days

I

P

− 0.39 ± 0.5

0.07 ± 0.35

No

-1.06

32

Cavalcante et al. 2012

Brazil

RCT

Patients with systemic inflammatory response syndrome

I = 15

P = 15

30gr/day

MT

Placebo

Oral

61

TNF-a

2 days

I

P

0.18 ± 0.35

− 0.03 ± 0.38

No

0.57

32

Cavalcante et al. 2012

Brazil

RCT

Patients with systemic inflammatory response syndrome

I = 15

P = 15

30gr/day

MT

Placebo

Oral

61

GSH

2 days

I

P

− 18.9 ± 162.5

− 34.9 ± 160.8

No

0.09