Table 2.
Description of diet studies that are presented in the diet section.
| Effects of Diet Composition Manipulation on Body Weight and Health | ||||||||
| Author | Year | Diet | Participants | n (M/F) | Duration | Main Findings | Ref | |
| 1 | Hall et al. | 2016 | Low-CHO ketogenic isocaloric diet or high-CHO diet | Overweight and obese men Mean age: 33 ± 1.8 y BMI: 28.8 ± 0.8 kg/m2 |
(17/0) | 4 weeks high-CHO diet and 4 weeks ketogenic diet |
Weight loss KD: 2.2 ± 0.3 kg (0.5 ± 0.2 kg from loss of body fat) BD: 0.8 ± 0.2 kg (0.5 ± 0.1 kg from loss of body fat) Increase in EEchamber, sleeping EE and EEDLW, decrease in RQ compared with baseline diet |
[152] |
| 2 | Foster et al. | 2010 | LCD or LFD (limiting energy intake to 1200 to 1500 kcal/d for women and 1500 to 1800 kcal/d for men, 55% CHO, 30% fat, 15% protein) |
Obese adults 45.5 ± 9.7 y BMI: 36.1± 3.5 kg/m2 |
(99/208) | 2 years | Weight loss LCD: −6.34 kg LFD: −7.37 kg Fat mass loss LCD: −3.99 kg LFD: −3.84 kg Higher increase in HDL in LCD group Similar reductions in TG, LDL, VLDL, systolic blood pressure |
[157] |
| 3 | Ebbeling et al. | 2012 | Isocaloric LFD (60% CHO 20% fat, 20% protein) or low-glycemic index diet (40% CHO, 40% fat, 20% protein), or VLCD (10% CHO, 60% fat, 30% protein) | Overweight and obese young adults Mean age: 30.3 ± 5.7 y BMI: 34.4 ± 4.9 kg/m2 |
(13/8) | Crossover design; 12 weeks | Highest decreases in REE and TEE with LFD. Leptin level was highest in the LFD and lowest in the VLCD. HDL was highest in VLCD and lowest in LFD. | [159] |
| 4 | Hall et al. | 2015 | Isocaloric reduced fat diet or reduced CHO diet | Obese adults Mean age: 35.4 ± 1.74 y BMI: 35.9 ± 1.1 kg/m2 |
(10/9) | 5 to 7 weeks | Greater weight loss and increased fat oxidation in RC diet than RF diet at the 6th day and greater fat loss (463 ± 37 g) in the RF diet compared to the RC diet (245 ± 21 g). | [160] |
| 5 | Dyson et al. | 2007 | LCD (≤40 g CHO/day) or healthy-eating diet |
Overweight or obese with T2DM or non-diabetic Mean age: 52 ± 9 y BMI: 35.1 ± 7.0 kg/m2 |
(8/18) | 3 months | Weight loss LCD: −6.9 kg Healthy eating diet: −2.1 kg No difference in changes in HbA1c, ketone, or lipid levels. |
[169] |
| 6 | Goday et al. | 2016 | Very low-calorie-ketogenic (VLCK) or low-calorie diet | Obese adults with T2DM Mean age: 54.5 ± 8.4 y BMI: 33.07 ± 1.56 kg/m2 |
(31/58) | 4 months | Weight loss VLCK: −14.7 kg LC: −5 kg The reduction in HbA1c and glycemic control was greater in the VLCK group. |
[170] |
| 7 | Harvey et al. | 2019 | VLCKD (5% CHO) or LCD (15% CHO) or moderate-low CHO diet (MCD) (25% CHO) |
Healthy adults Mean age: 38.9 ± 7.1 y BMI: 27.0 ± 3.96 kg/m2 |
(14/25) | 12 weeks | Weight loss VLCKD: −4.12 kg LCD: −3.93 kg MCD: −2.97 kg Similar reductions in total cholesterol, LDL, TG, and increase in HDL |
[171] |
| 8 | Dalle Grave et al. | 2013 | HPD (34% protein, 46% CHO) or HCD (17% proteins, 64% CHO) |
Obese adults Mean age: 46.7 ± 11.1 y BMI: 45.6 ± 6.7 kg/m2 |
(37/51) | 1 year | Weight loss HPD: −18.1 kg (15.0%) HCD: −15.9 (13.3%) Similar reductions in TG, LDL, total cholesterol, glucose, and insulin levels and increase in HDL. |
[179] |
| Effects of Plant-Based Diets on Body Weight and Health | ||||||||
| Author | Year | Diet | Participants | n (M/F) | Duration | Main Findings | Ref | |
| 1 | Wright et al. | 2017 | Low-fat plant-based diet (7–15% total energy from fat) or control | Obese, overweight, and diagnosed with at least one of T2DM, ischaemic heart disease, hypertension or hypercholesterolaemia Mean age: 56 ± 9.7 y BMI: 34.3 ± 1.9 kg/m2 |
(26/39) | 6 to 12 months | Significant reduction in BMI (4.2 kg/m2) in diet group | [191] |
| 2 | Thompson et al. | 2005 | Standard diet or high-dairy diet or high-fiber and high-dairy diet |
Obese adults Mean age: 41.4 ± 8.9 y BMI: 34.8 ± 3.1 kg/m2 |
(72/0) | 48 weeks | Similar weight loss in all diet groups Standard diet: 10.1 kg High-dairy diet: 11.7 kg High fiber and high dairy diet: 10.4 Similar fat mass loss in all diet groups Standard diet: −7.5 kg High-dairy diet: −9.0 kg High fiber and high dairy diet: −8.5 kg Similar increase in HDL and reductions in total cholesterol, LDL, fasting glucose and insulin, leptin, hs-CRP |
[197] |
| 3 | Turner-McGrievy et al. | 2015 | Vegan Vegetarian Pesco-vegetarian Semi-vegetarian Omnivorous |
Overweight or obese adults Mean age: 48.74 ± 7.5 y BMI: 34.96 ± 5.2 kg/m2 |
(17/46) | 6 months | Weight loss Vegan: −7.5% Vegetarian: −6.3% Pesco-vegetarian: −3.2% Semi-vegetarian: −3.2% Omnivorous: −3.1% |
[205] |
| Effects of Intermittent Fasting on Body Weight and Health | ||||||||
| Author | Year | Diet | Participants | n (M/F) | Duration | Main Findings | Ref | |
| 1 | Varady et al. | 2009 | Alternate day fasting (Fast day: 25% of energy needs, alternated day: ad libitum food intake) |
Obese adults Mean age: 46.0 ± 2.4 y BMI: 33.8 ± 1.0 kg/m2 |
(4/12) | 10 weeks | Weight loss −5.6 ± 1.0 kg Body fat percent decreased from 45 ± 2% to 42 ± 2% Significant decreases in total cholesterol, LDL, TG, and blood pressure |
[209] |
| 2 | Harvie et al. | 2011 | IER (∼2710 kJ/day for 2 days/week) or CER (∼6276 kJ/day for 7 days/week) |
Overweight or obese premenopausal women Mean age: 40.05 y BMI: 30.6 ± 5.1 kg/m2 |
(0/107) | 6 months | Weight loss IER: −6.4 kg CER: −5.6 kg Similar reductions in hs-CRP, leptin, total cholesterol, LDL, TG, and blood pressure. Reductions in fasting insulin and insulin resistance in both groups greater in the IER group. |
[212] |
| 3 | Schübel et al. | 2018 | ICR (5:2, weekly energy deficit ∼20%) or CCR (daily energy deficit ∼20%) or control group |
Overweight and obese adults Mean age: 50.2 ± 8 y BMI: 31.4 ± 3.8 kg/m2 |
ICR: n: 49 CCR: n: 49 Control: n:52 |
50 weeks | Weight loss ICR: −5.2% ± 1.2%, CCR: −4.9% ± 1.1% Control: −1.7% ± 0.8% Similar reductions LDL, HDL, cholesterol, TG, insulin, HOMA-IR levels, and adipokines (adiponectin, leptin) |
[213] |
BMI, body mass index. CER, continuous energy restriction. CCR, continuous calorie restriction. CHO, carbohydrate. EE, energy expenditure. EEDLW, energy expenditure measured by doubly labeled water. HCD, high-carbohydrate diet. HDL, high-density lipoprotein. hs-CRP, high sensitivity C-reactive protein. HPD, high-protein diet. ICR, intermittent calorie restriction. IER, intermittent energy restriction. LCD, low-carbohydrate diet. LDL, low-density lipoprotein. LFD, low-fat diet. REE, resting energy expenditure. TEE, total energy expenditure. TG, triglyceride. T2D, type 2 diabetes. VLCD, very low-carbohydrate diet. VLCK, very low-calorie-ketogenic. VLCKD, very low-carbohydrate ketogenic diet. VLDL, very low-density lipoprotein.