Table 2.
Intakes of subtypes of grains and effect on coronary heart disease, stroke, cardiovascular disease, cancer, and mortality. Analysis of high versus low intake and dose-response analysis
| Type of grain | High v low analysis | Dose-response analysis | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| No of studies | RR* (95% CI) | I2 | P value† | Dose (g/day) | No of studies | RR* (95% CI) | I2 | P value† | ||
| Coronary heart disease | ||||||||||
| Whole grain bread | 7 | 0.83 (0.75 to 0.92) | 0 | 0.64 | 90 | 5 | 0.83 (0.76 to 0.92) | 0 | 0.53 | |
| Whole grain breakfast cereals | 4 | 0.72 (0.64 to 0.82) | 0 | 0.92 | 30 | 4 | 0.81 (0.75 to 0.88) | 0 | 0.69 | |
| Rye products | 2 | 0.81 (0.70 to 0.94) | 0 | 0.47 | 30 | 2 | 0.97 (0.91 to 1.05) | 54 | 0.14 | |
| Added bran | 3 | 0.78 (0.63 to 0.95) | 65 | 0.06 | 10 | 2 | 0.72 (0.58 to 0.89) | 34 | 0.22 | |
| Germ | 2 | 0.73 (0.33 to 1.64) | 65 | 0.09 | 2 | 2 | 0.88 (0.76 to 1.03) | 0 | 0.65 | |
| Refined grains | 4 | 1.16 (0.84 to 1.59) | 48 | 0.12 | 90 | 5 | 1.13 (0.90 to 1.42) | 57 | 0.05 | |
| White bread | 2 | 1.07 (0.86 to 1.34) | 50 | 0.16 | 90 | 2 | 0.96 (0.53 to 1.76) | 86 | 0.007 | |
| Refined grain breakfast cereals | 2 | 1.15 (0.79 to 1.67) | 70 | 0.07 | 30 | 2 | 1.14 (0.75 to 1.73) | 72 | 0.06 | |
| Total rice | 4 | 0.98 (0.90 to 1.07) | 0 | 0.44 | 100 | 4 | 0.99 (0.95 to 1.03) | 7 | 0.36 | |
| Total grains | 3 | 1.07 (0.91 to 1.25) | 0 | 0.47 | 90 | 2 | 1.07 (0.88 to 1.30) | 0 | 0.40 | |
| Stroke | ||||||||||
| Whole grain bread | 2 | 0.88 (0.75 to 1.03) | 0 | 0.89 | 90 | 1 | 0.88 (0.72 to 1.07) | — | — | |
| Whole grain breakfast cereals | 2 | 0.99 (0.53 to 1.86) | 77 | 0.04 | 30 | 2 | 1.07 (0.69 to 1.64) | 78 | 0.03 | |
| Refined grains | 4 | 0.95 (0.78 to 1.14) | 23 | 0.28 | 90 | 5 | 0.91 (0.81 to 1.02) | 29 | 0.23 | |
| Total rice | 4 | 1.02 (0.94 to 1.11) | 0 | 0.95 | 100 | 4 | 1.00 (0.97 to 1.03) | 0 | 0.87 | |
| Total grains | 4 | 0.89 (0.79 to 1.00) | 6 | 0.36 | 90 | 5 | 0.93 (0.85 to 1.02) | 62 | 0.03 | |
| Cardiovascular disease | ||||||||||
| Whole grain bread | 4 | 0.83 (0.75 to 0.92) | 0 | 0.78 | 90 | 3 | 0.87 (0.80 to 0.95) | 0 | 0.71 | |
| Whole grain breakfast cereals | 2 | 0.74 (0.65 to 0.84) | 4 | 0.31 | 30 | 2 | 0.84 (0.78 to 0.90) | 0 | 0.82 | |
| Bran | 3 | 0.82 (0.76 to 0.88) | 0 | 0.64 | 10 | 2 | 0.85 (0.79 to 0.90) | 0 | 0.37 | |
| Germ | 2 | 1.06 (0.97 to 1.16) | 0 | 0.41 | 2 | 2 | 1.05 (0.96 to 1.15) | 0 | 0.41 | |
| Refined grains | 2 | 1.02 (0.91 to 1.14) | 16 | 0.27 | 90 | 3 | 0.98 (0.90 to 1.06) | 56 | 0.11 | |
| Total breakfast cereals | 2 | 0.80 (0.70 to 0.90) | 55 | 0.14 | 30 | 3 | 0.80 (0.68 to 0.93) | 73 | 0.03 | |
| Total rice | 3 | 0.96 (0.90 to 1.03) | 0 | 0.54 | 100 | 3 | 0.98 (0.95 to 1.00) | 0 | 0.47 | |
| Total grains | 3 | 0.94 (0.84 to 1.06) | 0 | 0.47 | 90 | 1 | 0.83 (0.70 to 1.00) | — | — | |
| Total cancer | ||||||||||
| Whole grain bread | 3 | 0.89 (0.78 to 1.01) | 42 | 0.18 | 90 | 3 | 0.91 (0.85 to 0.96) | 0 | 0.63 | |
| Brown rice | 3 | 1.07 (0.91 to 1.26) | 27 | 0.26 | 100 | 3 | 0.98 (0.92 to 1.04) | 0 | 0.61 | |
| Refined grains | 1 | 0.98 (0.82 to 1.16) | — | — | 90 | 2 | 0.94 (0.90 to 0.99) | 0 | 0.60 | |
| White rice | 3 | 0.87 (0.76 to 1.01) | 53 | 0.12 | 100 | 3 | 0.98 (0.92 to 1.05) | 49 | 0.14 | |
| Total breakfast cereals | 1 | 0.90 (0.86 to 0.95) | — | — | 30 | 2 | 0.90 (0.82 to 1.00) | 36 | 0.21 | |
| Total rice | 4 | 0.95 (0.88 to 1.02) | 65 | 0.03 | 100 | 4 | 0.98 (0.95 to 1.01) | 55 | 0.08 | |
| Total grains | 1 | 0.92 (0.80 to 1.06) | — | — | 90 | 2 | 0.97 (0.96 to 0.99) | 0 | 0.51 | |
| All cause mortality | ||||||||||
| Whole grain bread | 5 | 0.81 (0.74 to 0.88) | 57 | 0.05 | 90 | 2 | 0.85 (0.82 to 0.89) | 0 | 0.36 | |
| Whole grain breakfast cereals | 3 | 0.79 (0.72 to 0.86) | 50 | 0.14 | 30 | 2 | 0.87 (0.84 to 0.90) | 0 | 0.85 | |
| Oats or oatmeal | 3 | 0.89 (0.76 to 1.04) | 90 | <0.001 | 20 | 1 | 0.88 (0.83 to 0.92) | — | — | |
| Refined grains | 2 | 1.02 (0.93 to 1.12) | 0 | 0.64 | 90 | 4 | 0.95 (0.91 to 0.99) | 20 | 0.29 | |
| Pasta | 1 | 0.61 (0.26 to 1.45) | — | — | 150 | 2 | 0.85 (0.74 to 0.99) | 54 | 0.14 | |
| Total bread | 3 | 0.77 (0.72 to 0.81) | 0 | 0.42 | 90 | 3 | 0.83 (0.80 to 0.85) | 0 | 0.41 | |
| Total breakfast cereals | 2 | 0.87 (0.81 to 0.93) | 47 | 0.17 | 30 | 3 | 0.89 (0.83 to 0.96) | 92 | <0.001 | |
| Total grains | 13 | 0.91 (0.87 to 0.95) | 4 | 0.41 | 90 | 7 | 0.96 (0.90 to 1.02) | 71 | 0.002 | |
*RR<1 favours those with higher intake.
†P for heterogeneity.