TABLE 1.
Characteristics of participants by quintiles of habitual dietary intake of α-linolenic acid (ALA)1
| Quintile of ALA (g/d) |
||||||
| Variable | 0.16–0.38 | 0.39–0.53 | 0.54–0.70 | 0.71–0.91 | 0.92–2.31 | P for trend2 |
| n | 69 | 72 | 73 | 69 | 70 | |
| Nutritional factors | ||||||
| Total energy intake (kJ/d) | 4105 ± 2383 | 5242 ± 234 | 6237 ± 234 | 7336 ± 238 | 9560 ± 238 | <0.0001 |
| Fatty acid intakes adjusted for total energy intake (g/d) | ||||||
| Linoleic acid4 | 4.73 ± 0.26 | 6.26 ± 0.24 | 6.62 ± 0.22 | 7.9 ± 0.24 | 11.35 ± 0.28 | <0.0001 |
| γ-Linolenic acid | 0.01 ± 0.001 | 0.01 ± 0.001 | 0.01 ± 0.001 | 0.01 ± 0.001 | 0.01 ± 0.001 | 0.50 |
| Arachidonic acid | 7.4 ± 0.42 | 10.5 ± 0.38 | 11.0 ± 0.36 | 13.2 ± 0.39 | 17.6 ± 0.45 | <0.0001 |
| n−3 ≥20-carbon PUFAs | ||||||
| Including supplements | 0.13 ± 0.03 | 0.13 ± 0.03 | 0.18 ± 0.03 | 0.22 ± 0.03 | 0.26 ± 0.03 | <0.0001 |
| Excluding supplements | 0.12 ± 0.02 | 0.13 ± 0.02 | 0.16 ± 0.02 | 0.22 ± 0.02 | 0.21 ± 0.03 | <0.0001 |
| trans-Fatty acids | 1.8 ± 0.1 | 2.0 ± 0.1 | 1.9 ± 0.1 | 1.8 ± 0.1 | 2.1 ± 0.1 | 0.09 |
| Saturated fatty acids | 21.8 ± 0.9 | 22.3 ± 0.8 | 22.2 ± 0.8 | 21.4 ± 0.8 | 23.5 ± 0.9 | 0.04 |
| Monounsaturated fatty acids5 | 19.8 ± 0.8 | 21.7 ± 0.7 | 21.9 ± 0.7 | 22.1 ± 0.7 | 27.8 ± 0.9 | <0.0001 |
| Polyunsaturated fatty acids | 5.99 ± 0.28 | 7.61 ± 0.25 | 8.13 ± 0.24 | 9.53 ± 0.26 | 13.5 ± 0.30 | <0.0001 |
| Sociodemographic factors | ||||||
| Age (y) | 54.6 ± 0.3 | 54.7 ± 0.3 | 54.4 ± 0.3 | 54.5 ± 0.4 | 53.8 ± 0.3 | 0.67 |
| Education (y) | 14.2 ± 0.3 | 14.1 ± 0.2 | 14.6 ± 0.3 | 14.1 ± 0.2 | 14.3 ± 0.3 | 0.67 |
| Married [n (%)] | 48 (70) | 55 (76) | 64 (88) | 56 (81) | 56 (80) | 0.18 |
| Lifestyle factors | ||||||
| Waist-to-hip ratio | 0.94 ± 0.01 | 0.95 ± 0.01 | 0.94 ± 0.01 | 0.94 ± 0.01 | 0.95 ± 0.01 | 0.20 |
| BMI (kg/m2) | 29.4 ± 0.5 | 29.3 ± 0.5 | 28.9 ± 0.5 | 28.8 ± 0.5 | 30.0 ± 0.6 | 0.18 |
| Physical activity (unit) | 7.1 ± 0.2 | 7.12 ± 0.2 | 7.7 ± 0.2 | 7.8 ± 0.2 | 7.3 ± 0.2 | 0.32 |
| Current smokers [n (%)] | 15 (22) | 15 (21) | 15 (21) | 15 (22) | 12 (17) | 0.61 |
| Clinical and biochemical features | ||||||
| Depression symptom score (BDI units) | 5.1 ± 0.8 | 4.5 ± 0.7 | 5.1 ± 0.8 | 4.8 ± 0.8 | 4.9 ± 0.8 | 0.88 |
| Plasma glucose (mmol/L) | 5.39 ± 0.12 | 5.61 ± 0.12 | 5.56 ± 0.12 | 5.67 ± 0.12 | 5.45 ± 0.12 | 0.68 |
| Systolic blood pressure (mm Hg) | 130 ± 1.8 | 129 ± 1.8 | 129 ± 1.8 | 130 ± 1.8 | 129 ± 2 | 0.93 |
| Diastolic blood pressure (mm Hg) | 81 ± 1.2 | 80 ± 1.2 | 81 ± 1.2 | 81 ± 1.3 | 81 ± 1.3 | 0.61 |
| Plasma lipids (mmol/L) | ||||||
| Total triglycerides | 2.11 ± 0.12 | 1.91 ± 0.12 | 2.00 ± 0.12 | 2.00 ± 0.12 | 2.22 ± 0.14 | 0.11 |
| Total cholesterol | 4.84 ± 0.12 | 4.86 ± 0.12 | 4.86 ± 0.11 | 4.94 ± 0.12 | 4.73 ± 0.12 | 0.61 |
| HDL cholesterol | 1.03 ± 0.03 | 1.00 ± 0.03 | 0.99 ± 0.03 | 1.02 ± 0.03 | 0.96 ± 0.03 | 0.20 |
| LDL cholesterol | 3.10 ± 0.10 | 3.18 ± 0.10 | 3.15 ± 0.10 | 3.28 ± 0.10 | 3.13 ± 0.10 | 0.98 |
| Use of statins [n (%)] | 21 (30) | 15 (21) | 19 (26) | 16 (23) | 18 (26) | 0.91 |
| Use of aspirin [n (%)] | 13 (19) | 16 (22) | 20 (27) | 20 (29) | 21 (30) | 0.12 |
| Use of antihypertensives [n (%)] | 11 (16) | 16 (22) | 17 (23) | 20 (29) | 22 (31) | 0.02 |
| Use of antihyperglycemics [n (%)] | 3 (4.4) | 9 (12.5) | 6 (8.2) | 7 (10.1) | 7 (10.1) | 0.46 |
1
BDI, Beck Depression Inventory; PUFAs, polyunsaturated fatty acids.
2
Test for trend across diet groups.
3
Least-squares mean ± SEM estimated from linear mixed models accounting for clustering within a pair unless otherwise indicated (all such values).
4
Excludes trans- and trans-cis-linoleic acid.
5
Excludes trans-monounsaturated fatty acids.