Table 1

 Characteristics of included randomised controlled trials in adults

TrialParticipantsIntervention*Control*Duration (years)†, country
Aukland reduced fat (Ley 2004)16 176 adults with impaired glucose toleranceReduced fat diet (no specific goal)Usual diet4.1, New Zealand
BDIT pilot studies (Boyd 1996)17295 women with dysplasia on mammographyTotal fat 15%, replace fat by complex carbohydratesHealthy diet (no advice on fat)6.8 intervention, 7.5 control, Canada
beFIT 199718-20409 people with mild hypercholesterolaemiaTotal fat <30%, saturated fat <7%, dietary cholesterol <200 mg/dayDelayed dietary changesUnclear (maximum 0.5), USA
Bloemberg 19912180 men with untreated raised total cholesterol levelsTotal fat 30%, polyunsaturated fat to saturated fat ratio 1.0, dietary cholesterol 20 mg/MJUsual diet0.5, Netherlands
BRIDGES (Hebert 2001)22106 women with recent stage I or II breast cancerTotal fat 20%, high fibre, plant basedNo formal interventionUnclear (1 maximum), USA
Canadian diet and breast cancer prevention (Boyd 1997)23≥896 women with mammographic densities >50%Total fat 15%, protein 20%, carbohydrates 65%, isocaloricUsual diet2.0, Canada
CARMEN 200024 25153 healthy people, body mass index 26-34Fat reduced by 10%, increased simple/complex carbohydratesAttain national “normal” intakeUnclear (maximum 0.5), Europe
CARMEN (metabolic syndrome substudy) 20022422 people with at least three risk factors for metabolic syndromeAs for CARMEN studyAs for CARMEN study0.5 intervention, 0.4 control, as for CARMEN study
De Bont 198126148 women with type 2 diabetesFat 30%, reducing intake of meat fat and dairy foods, improving saturated fat to polyunsaturated fat ratio, increasing intake of carbohydratesUsual diet with carbohydrates ≤40%0.5, UK
DEER (Stefanick 1998)27197 men and 180 postmenopausal women with raised low density lipoprotein and reduced high density lipoprotein cholesterol levelsNational cholesterol education programme step 2 diet: fat <30%, saturated fat <7%, <200 mg/day dietary cholesterolUsual diet1.0, USA
German fat reduced (Seppelt 1996)2870 women with body mass index 24-29Buy low fat foods from trial shopBuy usual fat foods from trial shop0.8 intervention, 0.7 control, Germany
Kentucky low fat (Anderson 1990)29 30118 moderately hypercholesterolaemic, non-obese white peopleFats 25%, protein 20%, carbohydrates 55%, dietary cholesterol <200 mg/dayNo diet intervention0.9, USA
Sarkkinen 199331159 community dwelling people with serum total cholesterol levels 6.5-8.0 mmol/LAmerican Heart Association diet: total fat 30%, saturated fat <10%, monounsaturated fat 10%, polyunsaturated fat 10%. Low fat diet: total fat 28-30%, saturated fat <14%, monounsaturated fat 10%, polyunsaturated fat 4%Monounsaturated fat diet: fat 38%, saturated fat <14%, monounsaturated fat 18%, polyunsaturated fat <6%.
Control diet: fat 38%, saturated fat <18%, monounsaturated fat 15%, polyunsaturated fat <5%
0.5, Finland
Mastopathy diet (Boyd 1988)3221 women with severe cyclical mastopathyTotal fat 15%, carbohydrates 65%Healthy diet, no advice on fat 0.45, Canada
MeDiet (Castagnetta 2006)33115 healthy postmenopausal women with high testosterone levelsSicilian diet (reduced intake of total, saturated, and omega 6 fats, increased intake of fish, whole cereals, legumes, seeds, fruit, and vegetables)Increase fruit and vegetable intake4.3, Italy
Moy 200134267 siblings of people with early coronary heart disease, with one or more risk factors for cardiovascular disease Nurse management, aim for total fat ≤40 g/dayPhysician risk management1.9, USA
MSFAT (Van het Hof 1995)35240 healthy people aged 20-55Trial shop - low fat products ad libitumTrial shop - usual fat products ad libitum0.5, Netherlands
National Diet Heart Study (Open 1st and 2nd) 196836821 community dwelling menDiet B: fat 30%, saturated fat <9%, dietary cholesterol 400 mg/day, polyunsaturated fat 15%, polyunsaturated to saturated fat ratio 1.5. Diet X: fat 30%, saturated fat <9%, dietary cholesterol 400 mg/day, polyunsaturated fat 15%, polyunsaturated to saturated fat ratio 1.5Fat 40%, saturated fat 16-18%, dietary cholesterol 700 mg/day, polyunsaturated to saturated fat ratio 0.40.9, USA
National Diet Heart Study (Open 2nd) 196836498 community dwelling menDiet BC fat 30-40%, saturated fat reduced, dietary cholesterol 400 mg/day, polyunsaturated to saturated fat ratio 1.5-2.0Fat 40%, saturated fat 16-18%, dietary cholesterol 700 mg/day, polyunsaturated to saturated fat ratio 0.40.6, USA
Nutrition and breast health (Djuric 2002)37122 premenopausal women at increased risk of breast cancerTotal fat 15%Daily food guide pyramid0.8 intervention, 1.0 control, USA
Pilkington 19603835 men with angina or who had a myocardial infarctionFat 20 g/day, avoid dairy except skimmed milk and one egg or 21 g cheese daily. Lean meat and fish each once daily, carbohydrates unlimitedAims for fat intake unclear, only skimmed milk, 90 mL/day soya oil, lean meat, unsaturated margarine1.1, UK
Polyp Prevention Trial 199639 402079 people with one or more large bowel polypsFat 20%, 18 g fibre/1000 kcal, 5-8 servings daily of fruit and vegetablesGeneral dietary guidelines3.1, USA
Rivellese 19944163 adults with primary hyperlipoproteinaemiaFat 25%, saturated fat 8%, monounsaturated fat 15%, polyunsaturated fat 2%, dietary cholesterol <300 mg/day, carbohydrates 58%Fat 38%, saturated fat <10%, monounsaturated fat 20%, polyunsaturated fat 10%, dietary cholesterol <300 mg/day, carbohydrates 47%0.4, Italy
Simon low fat breast cancer 199042194 women at high risk of breast cancerTotal fat 15%Usual diet1.7 intervention, 1.8 control, USA
Sondergaard 200343115 people with ischaemic heart disease plus total cholesterol ≥5 mmol/LFat and saturated fat reduced, replace fats with oils, 600 g fruit and vegetables daily, fatty fish once or more weekly, carbohydrates freelyUnclear1.0, Denmark
Strychar 20094430 people with well controlled type 1 diabetes mellitusFat 27-30%, saturated fat ≤10%, monounsaturated fat 10%, carbohydrates 54-57%Fat 38%, saturated fat ≤10%, monounsaturated fat 20%, carbohydrates 45%0.5, Canada
Swedish breast cancer 199045-47169 women after breast cancer surgeryFat 20-25%, replace energy with carbohydratesUsual diet1.5 intervention, 1.9 control, Sweden
Veterans dermatology (Black 1994)48115 people with non-melanoma skin cancerFat 20%, protein 15%, carbohydrates 65%No dietary advice1.9, USA
Women’s Healthy Eating and Living (Pierce 2007)493088 women with breast cancer treated earlyFat 15-20%, increase intake of fruit and vegetables plus 16 oz vegetable juice daily Fat 30%11, USA
Women’s Health Initiative (Howard 2006)5048 835 postmenopausal womenFat 20%, with increased intake of fruit, vegetables, and grainsUnclear, diet related education8.1, USA
Women’s Health Trial: Feasibility 199051261 women at risk of breast cancerFat 20%Usual diet1.9, USA
Women’s Health Trial: Feasibility Study in Minority Populations 200351 1720 postmenopausal women, diverse ethnic and socioeconomic statusFat ≤20%, reduced saturated fat and dietary cholesterol, increased fruit, vegetables, and whole grainsUsual dietUnclear (1.5 maximum), USA
Women’s Intervention Nutrition Study (Chlebowski 1993)522437 women with resected breast cancerFat 15-20%Nutritional adequacy5.0, USA

*Percentages refer to proportion of total energy intake.

†Mean years in trial (not maximal duration).