Table 1 Characteristics of the included studies
Study | Country of origin | Original design | Number of participants (Male/Female) | Age (years) | Follow-up (years) | Dairy products type | Group cut-off value |
Bonthuis et al. (2010) [21] | Australia | Cohort | 663/856 | 25–78 | 14.4 | Total dairy | Mean: (163; 339; 628) g/day |
Breslow et al. (2000) [22] | America | Cohort | 8363/11641 | 18–87 | 8.5 | Total dairy | (0–3.0; 3.0–7.0; 7.0–10.0; >10.0) servings/day |
Chow et al. (1992) [23] | America | Cohort | 17633/0 | >35 | 20 (maximum) | Total dairy | (<46; 46–95; 96–142; >142) servings/month |
Kelemen et al. (2005) [24] | America | Cohort | 0/29017 | 55–69 | 15 | Total dairy | Median: (1.0; 1.13; 1.24; 1.34; 1.45) servings/1000 kcal |
Kojima et al. (2004) [25] | Japan | Cohort | 45181/62643 | 40–79 | 9.9 | Milk | (seldom; 0.5–4 servings/week; everyday) |
Yogurt | (seldom; 1–2 servings/month; 1–7 servings/week) | ||||||
Cheese | (seldom; 1–2 servings/month; 1–7 servings/week) | ||||||
Butter | (seldom; 1–2 servings/month; 1–7 servings/week) | ||||||
Matsumoto et al. (2007) [26] | Japan | Cohort | 4531/7075 | 19–93 | 9.2 | Milk, butter and yogurt | (not everyday; everyday) |
Park et al. (2007) [27] | America | Cohort | 293888/0 | 50–71 | 6 (maximum) | Whole milk | (0; 0–0.5; 0.5–1; 1–2; > = 2) servings/day |
Low-fat milk | (0; 0–0.5; 0.5–1; 1–2; > = 2) servings/day | ||||||
Skim milk | (0; 0–0.5; 0.5-1; 1–2; > = 2) servings/day | ||||||
Cheese | (<0.1; 0.1–0.25; 0.25–0.5; 0.5–0.75; > = 0.75) servings/day | ||||||
Yogurt | (0; 0–0.5; > = 0.5) servings/day | ||||||
Praagman et al. (2015) [28] | Europe | Cohort | 8901/25508 | 20–70 | 15 | Fermented dairy | Median: (8.8; 52.2; 128; 351) g/day |
Yogurt | Median: (3.8; 26.2; 62.9; 144.5) g/day | ||||||
Cheese | Median: (6.6; 19.6; 31.8; 53.2) g/day | ||||||
Sharma et al. (2013) [29] | Multiethnic | Cohort | 70333/76056 | 45–75 | NA | Total dairy | (<=0.5; 0.6–1.0; 1.1–1.6; >1.6) servings/day |
Song et al. (2013) [30] | America | Cohort | 21660/0 | 40–84 | 28 (maximum) | Total dairy | (<=0.5; 0.5–1.0; 1.0–1.5; 1.5–2.5; >2.5) servings/day |
Whole milk | (<=1; 2–6; > = 7) servings/week | ||||||
Skim/low-fat milk | (<=1; 2–6; > = 7) servings/week | ||||||
Wang et al. (2015) [31] | Japan | Cohort | 39639/55341 | 40–79 | 19 | Milk | (0; 1–2 servings/month; 1–2 servings/week; 3–4 servings/week; everyday) |
Study | Cancer type | Endpoints | Adjusted factors | Quality assessment | |||
Bonthuis et al. (2010) [21] | All cancer | All cancer death | Age, sex, total energy intake, body mass index, alcohol intake, school leaving age, physical activity level, pack years of smoking, dietary supplement use, b-carotene treatment during trial and presence of any medical condition | 9 | |||
Breslow et al. (2000) [22] | Lung cancer | Lung cancer death | Age, sex, smoking duration and packs per day smoked | 8 | |||
Chow et al. (1992) [23] | Lung cancer | Lung cancer death | Age, smoking status and industry/occupation | 8 | |||
Kelemen et al. (2005) [24] | All cancer | All cancer death | Age, total energy, carbohydrate, saturated fat, polyunsaturated fat, monounsaturated fat, trans-fat total fiber, dietary cholesterol, dietary methionine, alcohol, smoking, activity level, body mass index, history of hypertension, postmenopausal hormone use, multivitamin use, vitamin E supplement use, education and family history of cancer | 6 | |||
Kojima et al. (2004) [25] | Colon and rectal cancer | Colon and rectal cancer death | Age, family history of colorectal cancer, body mass index, frequency of alcohol intake, current smoking status, walking time per day, and educational level | 9 | |||
Matsumoto et al. (2007) [26] | Colon, stomach, lung, liver, pancreatic, bile duct and blood cancer | Colon, stomach, lung, liver, pancreatic, bile duct and blood cancer death | Age and sex | 9 | |||
Park et al. (2007) [27] | Prostate cancer | Prostate cancer death and advanced prostate cancer | Age, race, education, marital status, body mass index, vigorous physical activity, smoking, alcohol consumption, history of diabetes, family history of prostate cancer, screening for prostate cancer by use of prostate-specific antigen, intakes of tomatoes, red meat, fish, vitamin E, alpha-linolenic acid and total energy | 8 | |||
Praagman et al. (2015) [28] | All cancer | All cancer death | Age, sex, total energy intake, smoking habit, body mass index, physical activity, education level, hypertension at baseline, intakes of alcohol and energy-adjusted intakes of fruit and vegetables | 9 | |||
Sharma et al. (2013) [29] | All cancer | All cancer death | Time on study, years of education, energy intake, smoking behaviors, body mass index, physical activity, history of diabetes, alcohol intake, history of hormone replacement therapy, and history of oophorectomy | 8 | |||
Song et al. (2013) [30] | Prostate cancer | Prostate cancer death | Age, cigarette smoking, vigorous exercise, alcohol intake, race, body mass index, baseline diabetes status, red meat consumption, total energy intake from recorded food items, assignment in the original aspirin trial and assignment in the original β-carotene trial. In addition, the models for whole milk and skim/low-fat milk were mutually adjusted for each other | 8 | |||
Wang et al. (2015) [31] | All cancer | All cancer death | Age categories, smoking status, drinking status, physical activity, sleeping duration, body mass index, education level, participation in health checkups, green-leafy vegetable intake, and history of hypertension, diabetes and liver disease | 9 | |||