Table 1.
Study characteristics: baseline participant characteristics of included randomized controlled trials
| Reference, year | Country | Duration | n (F/M) | Mean BMI, kg/m2 | Mean age, year | Health status | Lipid-lowering therapy (E/C) | Intervention | Control | Intervention program |
|---|---|---|---|---|---|---|---|---|---|---|
| Cooper et al., 198217 | USA | 3 weeks | 15 (5/10) | NR | 28.0 | Healthy subjects | None | Lacto-vegetarian | Omnivorous | Dietary |
| Kestin et al., 198918 | Australia | 6 weeks | 26 (0/26) | 25.5 | 44.0 | NR | None | Lacto-ovo-vegetarian | High-fat omnivorous | Dietary |
| Ornish et al., 199019 | USA | 12 months | 41 (5/36) | 27.5 | 57.8 | With CAD | None | Low-fat lacto-ovo-vegetarian | Omnivorous | Multi-interventional |
| Ling et al., 199220 | Finland | 4 weeks | 18 (14/4) | 26.6 | 42.8 | Healthy or with unrelated conditions | NR | Uncooked vegan | Omnivorous | Dietary |
| Ornish et al., 199821 | USA | 5 years | 35 (3/32) | 27.1 | 59.3 | With CAD | 9 (0/9) | Low-fat lacto-ovo-vegetarian (Ornish) | Omnivorous | Multi-interventional |
| Nicholson et al., 199922 | USA | 12 weeks | 11 (5/6) | NR | 54.3 | With non-insulin dependent DM | 4 (3/1) | Low-fat vegan | Omnivorous | Dietary |
| Barnard et al., 200023 | USA | 2 months | 35 (35/0) | 25.5 | 36.1 | Healthy menopausal women | None | Low-fat vegan | Omnivorous | Dietary |
| Ågren et al., 200124 | Finland | 3 months | 29 (28/1) | 24.3 | 50.8 | With rheumatoid arthritis | None | Uncooked vegan | Omnivorous | Dietary |
| Gardner et al., 200525 | USA | 4 weeks | 120 (60/60) | 26.5 | 48.5 | Without DM or heart diseases | None | Low-fat lacto-ovo-vegetarian | Low-fat omnivorous | Dietary |
| Barnard et al., 200626 | USA | 22 weeks | 99 (60/39) | 34.9 | 55.6 | With T2DM | 54 (27/27) | Vegan | Omnivorous (ADA diet) | Dietary |
| Burke et al., 200627 | USA | 6 months | 182 (159/23) | 34.1 | 44.1 | Overweight and obese | 10 (8/2) | Lacto-ovo-vegetarian | Omnivorous | Multi-interventional |
| de Mello et al., 200628 | Brazil | 4 weeks | 17 (3/14) | 26.2 | 59.0 | With T2DM and macroalbuminuria | None | Low-protein lacto-vegetarian | Omnivorous | Dietary |
| Aldana et al., 200729 | USA | 12 months | 93 (40/53) | 31.0 | 61.5 | With CAD | Yes (N subjects NR) | Low-fat lacto-ovo-vegetarian (Ornish) | Omnivorous | Multi-interventional |
| Burke et al., 200730 | USA | 18 months | 176 (153/23) | 34.0 | 44.0 | Overweight and obese | None | Low-fat lacto-ovo-vegetarian | Low-fat omnivorous | Multi-interventional |
| Elkan et al., 200831 | Sweden | 12 months | 58 (52/6) | 24.0 | 50.3 | With rheumatoid arthritis | None | Gluten-free vegan | Omnivorous | Dietary |
| Barnard et al., 200932 | USA | 74 weeks | 99 (60/39) | 34.9 | 55.6 | With T2DM | 54 (27/27) | Vegan | Omnivorous (ADA diet) | Dietary |
| Miller et al., 200933 | USA | 4 weeks | 18 (9/9) | 22.6 | 30.6 | Healthy with BMI < 30 and no history of metabolic, hepatic, renal, or systemic disease | None | Low-fat lacto-ovo-vegetarian (Ornish) | Omnivorous (Mediterranean/South Beach) | Dietary |
| Kahleova et al., 201134 | Czech | 24 weeks | 74 (39/35) | 35.1 | 56.2 | With T2DM | 38 (22/16) | Lacto-vegetarian | Omnivorous (EASD diet) | Multi-interventional |
| Mishra et al., 201335 | USA | 18 weeks | 291 (242/50) | 35.0 | 45.2 | BMI ≥ 25 and/or T2DM | NR | Low-fat vegan | Omnivorous | Dietary |
| Bunner et al., 201436 | USA | 16 weeks | 42 (39/3) | 27.5 | 45.7 | With prior migraine diagnosis | NR | Low-fat vegan | Omnivorous | Dietary |
| Lee et al., 201637 | South Korea | 12 weeks | 93 (75/18) | 23.5 | 57.9 | With T2DM | 49 (23/26) | Vegan | Omnivorous (conventional diet recommended by the Korean Diabetes Association) | Dietary |
| Lee et al., 201738 | South Korea | 10 days | 30 (30/0) | 21.5 | 20.0 | Healthy subjects with no physical and/or psychological disease | NR | Lacto-ovo-vegetarian | Omnivorous | Multi-interventional |
| Wright et al., 201739 | New Zealand | 6 months | 65 (39/26) | 34.4 | 56.0 | Obese or overweight and with T2DM, IHD, hypertension, and/or hypercholesterolaemia | Yes (N subjects NR) | Low-fat vegan | Omnivorous | Dietary |
| Kahleova et al., 201840 | USA | 16 weeks | 75 (67/8) | 33.3 | 53.4 | Overweight and obese without DM | 9 (5/4) | Low-fat vegan | Omnivorous | Dietary |
| Shah et al., 201841 | USA | 8 weeks | 100 (15/85) | 30.7 | 61.3 | With CAD | 95 (47/48) | Vegan | Omnivorous (AHA diet) | Dietary |
| Sofi et al., 201842 | Italy | 3 months | 118 (92/26) | 30.6 | 50.0 | Clinically healthy, BMI ≥ 25, and the presence of ≥1 of the following: TC > 190 mg/dL, LDL-C > 115 mg/dL, TG > 150 mg/dL, and glucose levels 110–126 mg/dL | None | Low-calorie lacto-ovo-vegetarian | Low-calorie omnivorous | Dietary |
| Djekic et al., 202043 | Sweden | 10 weeks | 31 (2/29) | 28.0 | 67.0 | With IHD | 31 (16/15) | Lacto-ovo-vegetarian | Omnivorous | Dietary |
| Kahleova et al., 202044 | USA | 16 weeks | 244 (211/33) | 33.4 | 55.0 | Overweight and obese | NR | Low-fat vegan | Omnivorous | Dietary |
| Garousi et al., 202145 | Iran | 3 months | 75 (39/36) | 31.0 | 43.2 | Overweight and obese adults with NAFLD | None | Lacto-ovo-vegetarian | Omnivorous (standard weight-loss diet) | Dietary |
| Barnard et al., 202246 | USA | 16 weeks | 62 (48/14) | 33.3 | 57.4 | Overweight and obese | 23 (11/12) | Low-fat vegan | Omnivorous (Mediterranean) | Dietary |
Overweight, BMI 25–29.9 kg/m2, obese ≥ 29.9 kg/m2; ADA, American Diabetes Association; AHA, American Heart Association; BMI, body mass index; CAD, coronary artery disease; DM, diabetes mellitus; E/C, experimental/control group; EASD, European Association for the Study of Diabetes; IHD, ischaemic heart disease; NAFLD, non-alcoholic fatty liver disease; NR, not reported; Omnivorous, contains all food groups; T2DM, type 2 diabetes mellitus.