TABLE 2.
Risk of incident prediabetes (n = 902 cases) among those initially healthy (n = 1867) at exam 5 (baseline, 1991–1995) in the Framingham Heart Study Offspring Cohort, by mean total dairy and milk-based product intakes1
| HR (95% CI) |
||||||||
| Intake, by category2 | Median intake2 | Respondents/cases, n | Person-years, n | Crude rate | Model 1 | Model 2 | Model 3 | Model 4 |
| Total dairy | ||||||||
| 0 to <4 | 2.7 | 258/135 | 2475.2 | 5.5 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| 4 to <7 | 5.7 | 378/179 | 3926.7 | 4.6 | 0.81 (0.64, 1.01) | 0.82 (0.65, 1.03) | 0.83 (0.66, 1.05) | 0.79 (0.63, 1.00) |
| 7 to <14 | 10.1 | 746/368 | 7962.2 | 4.6 | 0.76 (0.62, 0.94) | 0.77 (0.63, 0.95) | 0.79 (0.63, 0.99) | 0.74 (0.59, 0.93) |
| ≥14 | 18.4 | 485/220 | 5439.2 | 4.0 | 0.63 (0.49, 0.80) | 0.65 (0.51, 0.82) | 0.67 (0.50, 0.88) | 0.61 (0.46, 0.81) |
| P-trend | 0.0003 | 0.001 | 0.009 | 0.002 | ||||
| High-fat dairy | ||||||||
| 0 to <1 | 0.7 | 165/79 | 1581.3 | 5.0 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| 1 to <4 | 2.6 | 887/418 | 9353.4 | 4.5 | 0.89 (0.69, 1.13) | 0.85 (0.67, 1.09) | 0.87 (0.68, 1.11) | 0.81 (0.63, 1.04) |
| 4 to <7 | 5.2 | 514/262 | 5518.4 | 4.7 | 0.83 (0.64, 1.08) | 0.80 (0.61, 1.04) | 0.79 (0.60, 1.03) | 0.72 (0.55, 0.95) |
| 7 to <14 | 8.9 | 236/110 | 2676.7 | 4.1 | 0.67 (0.49, 0.92) | 0.62 (0.46, 0.85) | 0.60 (0.43, 0.83) | 0.56 (0.40, 0.78) |
| ≥14 | 17.5 | 65/33 | 673.4 | 4.9 | 0.77 (0.50, 1.18) | 0.81 (0.52, 1.24) | 0.80 (0.51, 1.25) | 0.75 (0.47, 1.17) |
| P-trend | 0.046 | 0.06 | 0.04 | 0.03 | ||||
| Low-fat dairy | ||||||||
| 0 to <1 | 0.2 | 330/181 | 3124.6 | 5.8 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| 1 to <4 | 2.5 | 497/237 | 5223.5 | 4.5 | 0.80 (0.66, 0.97) | 0.81 (0.67, 0.99) | 0.82 (0.67, 1.00) | 0.79 (0.65, 0.97) |
| 4 to <7 | 5.4 | 392/190 | 4289.9 | 4.4 | 0.77 (0.63, 0.95) | 0.80 (0.65, 0.98) | 0.81 (0.65, 1.00) | 0.75 (0.61, 0.94) |
| 7 to <14 | 9.2 | 447/204 | 4980.1 | 4.1 | 0.74 (0.60, 0.90) | 0.76 (0.62, 0.94) | 0.78 (0.62, 0.99) | 0.73 (0.58, 0.91) |
| ≥14 | 17.6 | 201/90 | 2185.2 | 4.1 | 0.73 (0.56, 0.95) | 0.75 (0.57, 0.97) | 0.76 (0.56, 1.02) | 0.68 (0.51, 0.92) |
| P-trend | 0.03 | 0.049 | 0.13 | 0.03 | ||||
| Total milk | ||||||||
| 0 to <1 | 0.3 | 364/197 | 3561.6 | 5.4 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| 1 to <4 | 2.5 | 575/277 | 6198.5 | 4.5 | 0.76 (0.64, 0.92) | 0.75 (0.63, 0.91) | 0.76 (0.63, 0.92) | 0.76 (0.63, 0.92) |
| 4 to <7 | 5.3 | 423/186 | 4607.6 | 4.0 | 0.69 (0.56, 0.85) | 0.68 (0.56, 0.84) | 0.70 (0.57, 0.87) | 0.70 (0.57, 0.86) |
| 7 to <14 | 9.3 | 334/157 | 3588.7 | 4.4 | 0.76 (0.62, 0.95) | 0.77 (0.62, 0.95) | 0.82 (0.65, 1.02) | 0.78 (0.62, 0.98) |
| ≥14 | 17.5 | 171/88 | 1846.7 | 4.8 | 0.82 (0.63, 1.07) | 0.80 (0.62, 1.04) | 0.81 (0.61, 1.08) | 0.79 (0.59, 1.05) |
| P-trend | 0.34 | 0.32 | 0.52 | 0.353 | ||||
| Skim milk | ||||||||
| 0 to <1 | 0.1 | 492/254 | 4868.0 | 5.2 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| 1 to <4 | 2.3 | 559/271 | 6049.1 | 4.5 | 0.83 (0.69, 0.98) | 0.82 (0.69, 0.98) | 0.82 (0.68, 0.98) | 0.81 (0.68, 0.97) |
| 4 to <7 | 5.2 | 361/161 | 3946.4 | 4.1 | 0.79 (0.65, 0.97) | 0.81 (0.66, 0.99) | 0.83 (0.67, 1.03) | 0.83 (0.67, 1.02) |
| 7 to <14 | 9.2 | 307/143 | 3336.4 | 4.3 | 0.83 (0.67, 1.02) | 0.85 (0.69, 1.04) | 0.89 (0.71, 1.11) | 0.83 (0.66, 1.04) |
| ≥14 | 17.5 | 148/73 | 1603.4 | 4.6 | 0.85 (0.65, 1.11) | 0.84 (0.64, 1.10) | 0.84 (0.62, 1.12) | 0.82 (0.61, 1.10) |
| P-trend | 0.24 | 0.29 | 0.49 | 0.293 | ||||
| Whole milk | ||||||||
| 0 to <1 | 0 | 1587/763 | 16797.8 | 4.5 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| ≥1 | 2.5 | 280/139 | 3005.5 | 4.6 | 0.88 (0.73, 1.06) | 0.84 (0.70, 1.01) | 0.80 (0.66, 0.98) | 0.84 (0.69, 1.01) |
| P-trend | 0.17 | 0.07 | 0.03 | 0.073 | ||||
| Cheese | ||||||||
| 0 to <1 | 0.6 | 401/199 | 4073.7 | 4.9 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| 1 to <4 | 2.3 | 1071/502 | 11372.6 | 4.4 | 0.88 (0.74, 1.04) | 0.87 (0.73, 1.03) | 0.87 (0.73, 1.03) | 0.83 (0.70, 0.98) |
| ≥4 | 5.5 | 395/201 | 4356.9 | 4.6 | 0.88 (0.71, 1.09) | 0.91 (0.73, 1.13) | 0.92 (0.74, 1.14) | 0.86 (0.69, 1.07) |
| P-trend | 0.37 | 0.64 | 0.71 | 0.41 | ||||
| Cream and butter | ||||||||
| 0 to <1 | 0.4 | 543/264 | 5540.8 | 4.8 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| 1 to <4 | 2.2 | 579/275 | 6289.4 | 4.4 | 0.91 (0.77, 1.08) | 0.88 (0.74, 1.05) | 0.85 (0.72, 1.01) | 0.82 (0.69, 0.98) |
| 4 to <7 | 5.4 | 246/115 | 2693.7 | 4.3 | 0.84 (0.68, 1.06) | 0.84 (0.67, 1.05) | 0.80 (0.64, 1.01) | 0.78 (0.62, 0.97) |
| 7 to <14 | 10.1 | 277/141 | 2986.8 | 4.7 | 0.98 (0.79, 1.21) | 0.94 (0.76, 1.16) | 0.88 (0.71, 1.10) | 0.88 (0.71, 1.10) |
| ≥14 | 19.7 | 222/107 | 2292.5 | 4.7 | 0.93 (0.73, 1.17) | 0.86 (0.68, 1.10) | 0.75 (0.58, 0.97) | 0.76 (0.59, 0.98) |
| P-trend | 0.84 | 0.48 | 0.09 | 0.18 | ||||
| Yogurt | ||||||||
| 0 | 0 | 642/346 | 6208.5 | 5.6 | 1 (reference) | 1 (reference) | 1 (reference) | 1 (reference) |
| >0 to <1 | 0.3 | 554/265 | 5961 | 4.4 | 0.89 (0.76, 1.05) | 0.95 (0.81, 1.12) | 0.97 (0.82, 1.15) | 0.92 (0.78, 1.09) |
| 1 to <3 | 1.7 | 467/200 | 5336.6 | 3.7 | 0.77 (0.64, 0.92) | 0.81 (0.67, 0.97) | 0.80 (0.66, 0.98) | 0.76 (0.62, 0.92) |
| ≥3 | 4 | 204/91 | 2297.2 | 4.0 | 0.88 (0.69, 1.12) | 0.93 (0.73, 1.20) | 0.96 (0.73, 1.27) | 0.95 (0.72, 1.26) |
| P-trend | 0.12 | 0.23 | 0.35 | 0.333 | ||||
Cox proportional hazards models to estimate HRs (95% CIs) were adjusted as follows: Model 1 was adjusted for age, sex, and energy intake. Model 2 was adjusted as for model 1, plus parental history of diabetes, baseline smoking status, dyslipidemia or treatment, and hypertension or treatment. Model 3 was further adjusted for means of other dietary characteristics, including intake of coffee, nuts, fruits, vegetables, meats, alcohol, fish; the glycemic index (used as a measure of carbohydrate quality); and other dairy intake, as appropriate (for example, for associations of low-fat dairy intake, high-fat dairy intake was included in model 3). Model 4 was adjusted as for model 3, with further adjustment for baseline BMI and weight change over follow-up.
Units are servings per week, with the following grams per serving: skim milk, 245 g; whole milk, 245 g; cream, 15 g; sour cream, 12 g; sherbet and ice milk, 96 g; ice cream, 66 g; yogurt, 227 g; cottage and ricotta cheese, 105 g; cream cheese, 28 g; other cheese, 28 g; butter, 5 g.
Where Model 4 trends seemed to be potentially nonlinear, tests for nonlinearity were conducted using restricted cubic splines; these tests were statistically significant for total milk (P-nonlinear trend = 0.001), skim milk (P-nonlinear trend = 0.02), whole milk (P-nonlinear trend = 0.01), and yogurt (P-nonlinear trend = 0.04). Other potential nonlinear associations were not statistically significant.