Effect of a low-carbohydrate diet versus a low-fat, calorie-restricted diet on adipokine levels in obese, diabetic participants

Figures & data

Table 1 Baseline characteristics of participants randomly assigned to either a low-carbohydrate or low-fat diet

Variable	Low carbohydrate (n = 37)	Low fat (n = 42)
Age, years (SD)	60.8 (10.3)	58.6 (9.2)
BMI, kg/m^2 (SD)	38.2 (6.0)	36.1 (4.6)
Male gender, number (%)	30 (81.8)	40 (95.2)
Race, number (%)
White	14 (37.8)	18 (42.9)
Black	23 (62.0)	22 (52.4)
Other	0	2 (4.8)
Medications for diabetes, number (%)
Insulin	7 (20.0)	11 (32.4)
Metformin	25 (71.4)	18 (52.9)
Thiazolidinedione	5 (14.3)	6 (17.7)
Sulfonylurea	23 (65.7)	19 (55.9)
Hypertension, number (%)	27 (73.0)	33 (78.6)
Hyperlipidemia, number (%)	21 (56.8)	32 (76.2)
Coronary artery disease, number (%)	10 (27.0)	13 (31.0)
Cigarette smoking, number (%)	4 (10.8)	8 (19.1)

Notes: Values are expressed as means (SD), unless otherwise specified. There were no significant baseline differences between groups.

Abbreviations: SD, standard deviation; BMI, body mass index.

Table 2 Between group comparisons of the change in weight, adipokines, and metabolic data from baseline to month 6

Variable	Low carbohydrate (n = 37)	Low fat (n = 42)
Weight, kg
Baseline	118.7 (24.4)	115.4 (22.3)
Δfrom baseline to month 6	−4.0 (6.3)	−2.2 (5.3)
Waist circumference, cm
Baseline	121.0 (21.4)	121.9 (10.4)
Δfrom baseline to month 6	−2.4 (21.7)	2.4 (4.4)
Adiponectin, μg/mL
Baseline	13.4 (9.1)	16.0 (9.9)
Δfrom baseline to month 6	2.6 (8.4)	4.3 (14.6)
Leptin, ng/mL
Baseline	25.2 (14.7)	22.2 (18.3)
Δfrom baseline to month 6	−3.0 (11.9)	−5.6 (13.3)
TNF-α, pg/mL
Baseline	3.4 (7.1)	1.9 (1.1)
Δfrom baseline to month 6	−1.5 (7.1)	−1.5 (5.6)
Insulin, μU/mL
Baseline	22.9 (12.9)	26.8 (18.1)
Δfrom baseline to month 6	−3.7 (12.1)	1.9 (25.2)
HbAlc, %
Baseline	8.1 (1.8)	7.3 (1.5)
Δfrom baseline to month 6	−0.6 (1.2)	−0.1 (1.2)

Notes: Values are expressed as mean (standard deviation), unless otherwise specified. Weight, adipokines, and metabolic data did not differ significantly between groups at any point.

Table 3 Results from the multiple linear regression model to examine the association between dietary assignment and change in adipokines, while controlling for weight change from baseline to month 6

Variable	Coefficient	95% confidence interval	P value
Adiponectin
Diet assignment	−0.056	−0.113, 0.069	0.636
Weight change	0.016	−0.11, 0.12	0.927
Leptin
Diet assignment	0.183	−0.012, 0.165	0.090
Weight change	0.573	0.009, 0.032	0.001
TNF-α
Diet assignment	−0.038	−2.07, 0.149	0.749
Weight change	0.313	−0.005, 0.48	0.110

Table 4 Between group comparisons of the change in dietary intake from baseline to month 6

Variable	Low carbohydrate (n = 37)	Low fat (n = 42)
Caloric intake, kcal
Baseline	2056.0 (762.2)	1967 (708.1)
Δfrom baseline to month 6	−138.9 (1216.8)	−380.7 (796.3)
Carbohydrate, g
Baseline	202.4 (112.2)	211.2 (84.8)
Δfrom baseline to month 6	−46.7 (127.6)	−37.1 (123.4)
Protein, g
Baseline	94.0 (50.5)	88.2 (36.7)
Δfrom baseline to month 6	−8.1 (61.4)	−2.8 (45.7)
Fat, g
Baseline	98.7 (45.3)	87.9 (51.1)
Δfrom baseline to month 6	−5.9 (63.9)	−23.3 (48.8)

Notes: Values are expressed as mean (standard deviation), unless otherwise specified. Dietary intake did not differ significantly between groups at any point.