Table 3: Experimental studies: characteristics and results of data abstraction.

Author/year/
country
Design Study length
(week)
SubjectsDietary interventionOutcomes Quality
rating
Diet detailsControl for weight loss differences?ΔCRPΔHbA1c%Other

Brinkworth et al. (2004), Australia [25]2 group pretest/posttest comparison design with randomization64
F = 61%
M = 39%
μage = 61.8
Low-protein (15%)
CHO 55%
Fat 30%
versus
High-protein (30%)
CHO 40%
Fat 30%
Yes
Weight

difference between diets, but overall decrease
Low-protein:
pre: 4.2
post (64 wk): 3.6
High-protein:
pre: 5.0
post (64 wk): 3.8
* 
Low-protein:
pre: 6.2
post (64 wk): 6.6
High-protein:
pre: 6.5
post (64 wk): 6.6
NA 10

Giannopoulou et al. (2005), U.S. [27]3-group, pretest-posttest with randomization14
Female only
μage= 57
Diet only
CHO 40%
Fat 40% (MUFA 30%)
Exercise only
Diet and exercise
No for all three groups
No raw data available
NS Δ NS Δ in TNF-α or IL-6 for all three groups 8

Marfella et al. (2006), Italy [16]RCT52 
M/F data not given 
μage = 35.8
Wine: 4 oz. per day + Mediterranean diet
Control group: no wine + Mediterranean diet
No * 
Changes in raw CRP values
not available
= NS* 
Changes in HbA1c
Wine: −1.1 ± 0.06
Control: −1.2 ± 0.7
TNF-α   * 
Changes in raw TNF values
not available
IL-6 * Changes in raw IL-6 values
not available
5

Wolever et al. (2008), Canada [29]3 groups, pretest-posttest with randomization52
F = 54%
M = 46%
μage = 59.9
High GI
Low GI
Low CHO
CHO 20%–25%
Fat not provided, but high MUFA in Low-CHO diet
Yes
BMI
Low GI-diet:
(different in μCRP postintervention between low and high GI diets)
postintervention μ:
High GI: 2.75
Low GI: 1.95
Low CHO: 2.35
NS difference between groups, HbA1c rose during intervention
High GI: 6.34
Low GI: 6.34
Low CHO: 6.35
NA 9

Barnard et al. (2009), U.S. [24]2 groups, pretest-posttest74 
F = 61%
M = 39%
μage = 55.7
Vegan diet
CHO 75%
Fat 10%
Conventional
ADA diet
C 60–70%
Fat < 7% saturated fat
Yes
Weight change
* 
Vegan: ( )
.
Conventional: ( )
* 
(only using data prior to median adjustments)
Vegan:
( )

Conventional:
( = NS)

Total cholesterol decreased more in vegan group
8

Dostlova et al. (2009), Czech Republic [21]Quasi-experimental one group with two comparison groups (monitored in the hospital)2T2DM group 

F only
μage = 56.1
Very-low-calorie diet (550 kcal/day)No   (Δ in μCRP pre: 13.2 ± 3.5/post: 7.1 ± 2.4)Fasting glucose
(Δ in μfasting glucose pre/post)
HOMA: 5

Kozłowska et al. (2010), Poland [22]Quasi-experimental (one-group pretest-posttest)8
F = 41%
M = 59%
μage = 66.6
Low energy/Low protein diet (20% energy deficit, 0.8–1.0 g/kg)
CHO 60%
F 30%
No (Δ in μCRP pre/post intervention)
pre: 2.6 (0.4–13.9)
post: 3.4 (0.3–12.4)

(Δ in μHbA1c pre/post intervention)
pre: 7.7 ± 1.4
post: 7.3 ± 1.4
(Δ in μTNF pre/post intervention)
pre: 10.6 ± 7.5
post: 7.8 ± 5.1
4

Vetter et al. (2010), U.S. [17]RCT subgroup 26 
F = 11%
M = 89% 
μage = 59.7
Low-carb
CHO < 30 g/day
versus
Low-fat (DPP diet)
Fat < 30% + 500 kcal/day deficit
NoNot measured = NS* 
Changes in HbA1c
Low-carb:
−0.6 (1.2)
Low-fat:
−0.1 (1.2)
TNF-α
= NS* 
Changes in TNF
Low-carb:
−1.5 (7.1)
Low-fat:
−1.5 (5.6)
4

Azadbakht et al. (2011), study conducted in Iran. [18]Cross-over with randomization (with 4 week washout period)8
F = 59%
M = 41%
μage = 55
DASH diet
CHO 50–60%
Fat < 30%
*High in whole grains, fruits, vegetables. Low sodium
versus
control diet
Yes
Weight change
* 
DASH:
pre: 2.9 ± 0.31
post: 2.03 ± 0.27
Control:
pre: 3.11 ± 0.30
post: 2.92 ± 0.20
No measure of glycemic control Fibrinogen: * 
DASH:
μ change: 38.7
Control:
μ change: 140
10

Bozzetto et al. (2011),
Italy [19]
Preexperimental posttest only. Cross-over with randomization
(no washout)
4
F = 25%
M = 75%
μage = 59
High-carb/high-fiber/low GI
CHO 52%
MUFA 17%
*GI 58%
versus
High-MUFA diet
CHO 45%
MUFA 23%
*GI 88%
NoMUFA meal:
   (Δ in μCRP when compared with fasting CRP)
Fasting: 2.11 ± 2.02
3 h: 1.98 ± 1.99
6 h: 2 ± 2.06
NS Δ in μCRP after CHO/fiber meal
No measure of glycemic control NA6

Davis et al. (2011),
U.S. [26]
2 groups pretest-posttest with randomization subgroup of larger trial
24
F = 76%
M = 24%
μage = 54.5
Low-fat (DPP diet)
Fat < 25%
versus
Low-CHO (Atkins diet)
CHO < 20%
Yes, weight loss equal between groupsLow-fat:
Δ in μCRP
pre: 4.0 ± 0.77
post: 3.0 ± 0.77
Low-CHO:
Δ in μCRP
pre: 3.1 ± 0.42
post: 3.6 ± 0.68
 ns
μHbA1c reduced by 0.18 ± 0.16 for pooled groups
IL-6 ns
μWt loss: 11 lb. for
pooled groups
9

Itsiopoulos et al. (2010), Australia [20]Cross-over with randomization
(no washout)
24
F = 41%
M = 16%
μage = 59
Mediterranean Diet:
CHO 44%
Fat 40%
(>50% MUFA)
versus
Control diet: ad lib.
No * 
Med diet:
2.38 [1.66, 3.10]
Control:
2.49 [1.69, 3.30]
* 
Med diet:
6.8 [6.3, 7.3]
Control:
7.1 [6.5, 7.7]
HOMA, * 
Med diet:
5.2 (3.9, 6.6)
Control:
6.1 (4.4, 7.8)
7

Khoo et al. (2011), Australia [28] 2 groups pretest-posttest with randomization
52 
M only
μage = 60.2
Low-calorie diet
900 kcal/day
versus
High-protein, low-fat
Fat < 30% + 600 kcal/day deficit
NoLow-calorie: NS
pre: 3.82 ± 1
post (52 weeks): 3.79 ± 0.82
High-protein:
pre: 8.32 ± 1.29
post (52 weeks): 2.85 ± 1.01
Not provided, change in plasma glucose was ns.IL-6
Low-calorie: = NS
pre: 1.59 ± 0.29
post (52 weeks): 1.7 ± 0.42
High-protein: = NS
pre: 3.28 ± 0.37
post (52 weeks): 2.4 ± 0.52 ( group and time effect)
7

Mraz et al. (2011), Czech Republic [23]Quasi-experimental design with two comparison groups
2
F only
μage = 65.6
Very-low-calorie diet
600 kcal/day
Healthy and obese subjects did not receive diet
Noμ Δ in CRP
pre/post = 0.94 mg/L
  
Raw data not provided
Not provided
μ Δ in IL-6
pre/post = 0.8 pg/mL
4

Note: CRP: C-reactive protein; HbA1c: glycosylated hemoglobin; F: females; M: males; : mean; age: mean age; Δ: change in; HOMA: homeostatic model assessment; DPP: Diabetes Prevention Program; DASH: Dietary Approaches to Stop Hypertension; GI: Glycemic Index; MUFA: monounsaturated fatty acid; ns: not significant; C: energy from carbohydrates; F: energy from fat; *: Significance of between group differences.