Authors (Year)

Study Design

Subjects

Methods

Results

Groop (1993)

Single Blind Placebo Controlled

15 T2DM (8M; 7F)

Placebo Period 1: 8 weeks (placebo)

Study Phase: 48 weeks (15 g guar gum/day)

Placebo Period 2: 8 weeks (placebo)

	Placebo 1	Guar Gum	Placebo 2
A1C (%)	9.0 ± 0.3	8.5 ± 0.3	8.5 ± 0.3
Mean Plasma Glucose (mmol/L)	9.5 ± 0.5	9.2 ± 0.5	10.3 ± 0.5

Kirsten (1992)

Randomized

Open-labeled Controlled

41 (29M; 11F)

Study Phase: 3 months

Group A: 3 × 4 g daily of new guar preparation (GU-052, Steigerwald, Darmstadt, Germany)

Group B: 3 × 5 g daily of Glucotard (Beohringer, Mannheim, Germany)

Time	A1C (%)
Time	Group A	Group B
Initial	12.6 ± 2.6	12.0 ± 2.6
30 days	12.2 ± 2.3	11.7 ± 2.4
90 days	10.5 ± 1.5	10.9 ± 1.8

Uusitupa (1989)

Control Phase: Double Blind Parallel Group Treatment Phase: Open-labeled

39 T2DM (12M; 26F)

Control Phase: 3 months (Group A: 5 g guar gum granules TID or Group B: placebo)

Treatment Phase: 10 months (Group A & B: 5 g guar gum granules TID)

	Time (months)	FPG (mmol/L)		A1C (%)
	Time (months)	Group A (n = 20)	Group B (n = 19)	Group A (n = 20)	Group B (n = 19)
Control Phase	0	12.23 ± 2.37	12.80 ± 2.60	8.88 ± 1.35	9.41 ± 1.50
Control Phase	3	2.00 ± 2.32	13.87 ± 3.54	8.38 ± 1.24	9.35 ± 1.86
Treatment Phase	5	11.56 ± 2.59	12.53 ± 4.06	9.58 ± 1.94	9.93 ± 2.25
	7	11.79 ± 2.49	12.41 ± 3.25	9.39 ± 1.69	10.01 ± 2.13
	9	11.88 ± 2.50	12.13 ± 2.70	8.94 ± 2.04	9.21 ± 3.18
	11	12.69 ± 2.55	12.97 ± 3.21	9.36 ± 1.75	9.51 ± 1.79
	13	12.83 ± 2.59	13.01 ± 3.14	9.26 ± 2.19	9.57 ± 1.89
Two-way ANOVA		p < 0.001	NS	p < 0.05	NS

Wilson (1989)

Cross over

15 T2DM (12M; 3F)

Washout Phase 1:

6 weeks

Study Phase 1: 8 weeks

(Guar 5 g TID before main meals or metformin 0.5 g TID)

Washout Phase 2: 6 weeks

Study Phase 2: 8 weeks

(Guar 5 g TID before main meals or metformin 0.5 g TID)

	FPG (mmol)	A1C (%)
Sulfonylurea alone	12.9 ± 0.9	12.1 ± 0.5
Addition of guar	13.7 ± 1.3	13.0 ± 0.6
Addition of metformin	11.6 ± 1.2	12.4 ± 0.8
Significance: guar vs metformin	p < 0.01	NS
Significance: guar vs sulfonylurea alone	NS	NS
Significance: metformin vs sulfonylurea alone	p < 0.01	NS

Beattie (1988)

Randomized

27 T2DM (9M; 18F)

Study Phase: 20 weeks

Group A: low fat, high carb (80 g), low energy diet with 15 g of fiber

Group B: low fiber diet for 4 weeks, then changed; for 8 weeks as group A with 10 - 15 g of additional cereal fiber; for remaining time or 4 weeks; returned to low fiber diet with 15 g guar gum

Group C: low fiber diet; guar gum diet for 8 weeks; high cereal fiber diet for 8 weeks

Weeks	Type of Diet	A1C^a	FPG (mmol/l)
Group A
0	-	66 (58 to 74)	11.2 (8.4 to 14.0)
4	Low fiber	58 (52 to 64)^b	7.8 (5.5 to 10.1)^b
12	Low fiber	50 (40 to 60)^b	8.0 (4.7 to 11.3)^b
20	Low fiber	50 (38 to 61)^bc	7.8 (4.4 to 11.0)^b
Group B
0	-	64 (57 to 70)	9.6 (7.1 to 11.9)
4	Low fiber	60 (53 to 67)	8.2 (6.9 to 9.7)
12	High fiber	51 (46 to 55)^bc	7.4 (6.0 to 8.8)^c
20	Guar gum	49 (43 to 54)^bc	6.8 (5.0 to 8.7)
Group C
0	-	62 (50 to 74)	9.6 (6.7 to 12.5)
4	Low fiber	53 (45 to 61)^b	7.8 (4.9 to 10.7)^b
12	Guar gum	44 (38 to 50)^bc	6.5 (4.2 to 8.8)^bc
20	High fiber	45 (40 to 50)^bc	6.5(4.9 to 8.1)^b

^aUnits = mmolhydrox-yl-methylfurfural/mmolHb

^bSignificant reduction compared with beginning of trial (p < 0.05)

^cSignificant reduction compared with week 4 (p < 0.05)