Data about soy was provided by 3 cohorts. A significant protective effect of soybeans, and soymilk against type 2 diabetes risk was found in one cohort (11), but no associations with tofu (8) and miso soup (2) were found in the other cohorts.
| Author | Cohort name | Subjects | Years of follow-up | Cases | End point | Consumption of | Relative Risk (RR) | Adjustments |
| 11) Villegas R (2008) | The Shanghai Women's Health Study | 64,227 women aged 40-70. (China) | 4.6 (1997-2000 to 2004) | 1,605 | Type 2 diabetes mellitus incidence (self-reported) | Soybeans (dried and fresh) |
RR = 0.53 (0.45-0.62; P = < 0.0001) for the highest vs lowest quintile of consumption. Amount specific data (g/d): 2.8: RR = 1. 6.6: RR = 0.62 (0.54-0.73). 11.1: RR = 0.57 (0.48-0.60). 17.3: RR = 0.58 (0.50-0.68). 32.0: RR = 0.53 (0.45-0.62). Effect modification: Consumption of soybeans was inversely associated with the risk of type 2 DM among both premenopausal and postmenopausal women. The associations of soybean consumption with risk of type 2 DM were not modified by BMI or WHR. | Age, energy intake, BMI, waist-to-hip ratio, smoking, alcohol consumption, vegetable intake, fiber, physical activity, income level, educational level, occupation, and hypertension. |
| 11) Villegas R (2008) | The Shanghai Women's Health Study | 64,227 women aged 40-70. (China) | 4.6 (1997-2000 to 2004) | 1,605 | Type 2 diabetes mellitus incidence (self-reported) | Soy milk |
RR = 0.61 (0.54-0.70; P = < 0.0001) for the highest vs lowest quartile of consumption. Amount specific data (g/d): 0: RR = 1. 12.3: RR = 0.52 (0.39-0.68). 71.4: RR = 0.58 (0.51-0.66). 214.3: RR = 0.61 (0.54-0.70). Effect modification: Consumption of soybeans was inversely associated with the risk of type 2 DM among both premenopausal and postmenopausal women. The associations of soybean consumption with risk of type 2 DM were not modified by BMI or WHR. | Age, energy intake, BMI, waist-to-hip ratio, smoking, alcohol consumption, vegetable intake, fiber, physical activity, income level, educational level, occupation, and hypertension. |
| 11) Villegas R (2008) | The Shanghai Women's Health Study | 64,227 women aged 40-70. (China) | 4.6 (1997-2000 to 2004) | 1,605 | Type 2 diabetes mellitus incidence (self-reported) | Soy products other than soy milk |
RR = 0.88 (0.75-1.04; P = 0.13) for the highest vs lowest quintile of consumption. Amount specific data (g/d): 16.8: RR = 1. 31.8: RR = 0.79 (0.68-0.93). 46.4: RR = 0.59 (0.50-0.70). 64.3: RR = 0.78 (0.66-0.90). 103.6: RR = 0.88 (0.75-1.04). Effect modification: Consumption of soybeans was inversely associated with the risk of type 2 DM among both premenopausal and postmenopausal women. The associations of soybean consumption with risk of type 2 DM were not modified by BMI or WHR. | Age, energy intake, BMI, waist-to-hip ratio, smoking, alcohol consumption, vegetable intake, fiber, physical activity, income level, educational level, occupation, and hypertension. |
| 8) Song Y (2005) | The Women's Health Study | 38,018 women aged ≥ 45. (USA) | 8.8 (1993-2003) | 1,600 | Type 2 diabetes incidence (according to ADA criteria) | Tofu |
RR = 1.06 (0.75-1.49; P = 0.95) for the highest vs lowest tertile of consumption. Amount specific data (servings): None: RR = 1. 1-3/mo: RR = 0.95 (0.74-1.22). ≥ 1/wk: RR = 1.06 (0.75-1.49). | Age, total energy intake, smoking, exercise, alcohol use, history of hypertension, history of high cholesterol, family history of diabetes, fiber, glycemic load, magnesium, and total fat. |
| 2) Hirayama T. (1990) | No cohort name. | 265,118 adults (122,261 men, 142,857 women) aged ≥ 40 from 6 prefectures in Japan. | 17 (1966-1982) | 946? (454 men, 492 women) | Diabetes mortality | Soybean paste soup | RR = 1.01 (90% CI = 0.89-1.13; No P-value) for consumption ≥ 4 vs ≤ 3 times/wk. | Age and sex. |