Table 1

Trials evaluating dietary intervention alone on NAFLD-related outcomes

Author
(year); country		InterventionAge range; sample size (% male)Study durationOutcome measuresChanges to outcome measures postintervention
Yamamoto (2007);21
Japan		Low calorie (126 kJ/kg/d), low fat (20%), low iron (≤6 mg/d) and 1.1–1.2 g/kg/d protein37–74;
27 (52%)		6 monthsPrimary: AST, ALT
Other: WT, BMI, TG, TC, GLC, Iron, FER, TS		Primary:
↓ AST*
↓ ALT*
↓ WT* (4.8%) and ↓ BMI*
Lin (2009);20
Taiwan		VLCD of 450 kcal/day or 800 kcal/day18–65;
132 (34%)		12 weeksPrimary: NAFLD (ultrasound) resolution and improvement Other: WT, BMI, WC, FM, GLC, BP, TG95 completed trial;
NAFLD resolved in 5 cases (450 kcal group) and 10 cases (800 kcal group)
NAFLD improved in 17 cases (450 kcal group) and 21 cases (800 kcal group)
↓ WT* 9.14% (450 kcal/day), ↓ 8.98% (800 kcal/day), and ↓ BMI*
De Luis (2010);22
Spain		Low fat, low calorie (1500 kcal/day, 27% fat/53% CHO) or low CHO, low calorie diet (1507 kcal/day, 38% CHO/36% fat)29–64;
162 (29%)		3 monthsPrimary: AST, ALT
Other: WT, BMI, BP, TC, HDL, LDL, TG, FM, WC, WHR, GLC, INS, HOMA		Low fat (NAFLD):

  • ↓AST*

  • ↓ALT*

  • ↓WT* (3.9%) and ↓ BMI*

Low-CHO diet (NAFLD):

  • ↓AST*

  • ↓ALT*

  • ↓WT* (4.9%) and ↓ BMI*

Browning (2011);23
USA		Low CHO (<20 g/d) or low calorie (1200–1500 kcal/d)33–57;
18 (27%)		2 weeksPrimary: IHTG (MRS), AST, ALT
Other: WT, BMI, TC, TG, GLC		↓ IHTG* 28% (low cal), 55% (low CHO); ↓ AST*; ↑ ALT§ ; ↓ BMI* ↓ WT* (4.2% low cal and 4.7% low CHO) and ↓ BMI*
Kani (2014);24
Iran		Calorie restriction (200–500 kcal/day; 55% CHO, 15% protein, 30% fat)
Calorie restriction, low CHO (45% CHO, 20% protein, 35% fat)
Calorie restriction, low CHO + 30 g soy protein		43–52;
45 (46%)		8 weeksPrimary: AST, ALT
Other: WT, BMI, INS, TG, TC, HDL, LDL, ALP, FIB, MDA		↓ AST* and ALT* in all groups; greatest reduction seen in the soy group.
All diets saw ↓ WT*: 3.9%, 4.2%, 4.7%, respectively and ↓ BMI*
Razavi Zade (2016);25
Iran		Calorie restriction (350–700 kcal) or
Calorie restriction and DASH diet (rich in fruit, veg, whole grains and low fat dairy; low in saturated fats, cholesterol and sugar)		25–75;
60 (50%)		8 weeksPrimary: Steatosis grade (ultrasound), AST, ALT
Other: WT, VLDL, LDL, HDL		Steatosis grade improved on both diets; more cases improved on DASH (80% vs 43%)* ↓ AST* ↓ ALT* with DASH not low cal ↓ WT* ( 3.0% low cal and 4.6% DASH)

  • *Statistically significant; §No statistical difference.

  • ALP, alkaline phosphatase; ALT, alanine aminotransferase; AST, aspartate aminotransferase; BMI, body mass index (kg/m2); BP, blood pressure; CHO, carbohydrate; DASH, dietary approaches to stop hypertension; FER, ferritin; FIB, serum fibrinogen; FM, fat mass; GLC, glucose; HDL, high-density lipoprotein; HOMA, Homeostasis Model Assessment; IHTG, intrahepatic triglyceride; INS, insulin; LDL, low-density lipoprotein; MDA, malondialdehyde; MRS, magnetic resonance spectroscopy; NAFLD, non-alcoholic fatty liver disease; NMR, nuclear magnetic resonance; TC, total cholesterol; TG, triglyceride; TS, transferrin saturation; VLCD, very low calorie diet; VLDL, very low density lipoprotein; WC, waist circumference; WHR = waist:hip ratio; WT, weight.