Table 3.
A summary of the effects of linoleic acid consumption on lipid risk markers for cardiovascular disease in healthy individuals (ordered by date of publication).
| Author (Year) | Study | Subjects | Age | Duration | Treatment | Linoleic Acid Results |
|---|---|---|---|---|---|---|
| Bronsgeest-Schoute et al. (1979) [39] | Randomized crossover | 41 total 24 males 17 females |
19–35 years mean, 22.1 years |
4 weeks | 14 to 15% E LA (25 to 50 g/d), with at least 600 mg C for 2 wk, and 2 wk of less than 200 mg C. | ↑serum C (high C diet compared with low C diet) ↔TG |
| Sanders et al. (1983) [41] | Randomized double-blinded crossover | 10 total 6 males 4 females |
22–35 years | 4 weeks | 10 g/d fish oil supplement (1.7 g EPA and 1.2 g DHA) or vegetable oil (3.4 g/d LA) for 2 wk. | ↔total C, ↑TG, ↓HDL-C (compared with fish oil) |
| Iacono et al. (1991) [33] | Randomized crossover | 11 males | 44–62 years mean, 53.6 years |
100 days | Baseline period of 20 d (typical US diet, but meeting RDAs), followed by a lower LA diet (3.8% E; 16 g/100 g dietary fat) and a higher LA diet (10.8% E; 37.8 g/100 g dietary fat) for 40 d. | ↓total C, ↓LDL-C, ↓apoB (both diets compared to baseline; 10.8% E LA diet had further decreases) ↔HDL-C, ↔TG, ↑apoA1 (both diets compared to baseline) |
| Zock et al. (1992) [34] | Randomized multiple crossover |
56 total 26 males 30 females |
Males: 19–48 years mean, 25 years Females: 18–49 years mean, 24 years |
9 weeks | Three diets were followed for 3 wk: high in LA (12% E LA), high in SA (11.8% E SA; 3.9% E LA), and high elaidic acid (7.7% E elaidic acid; 3.8% E LA). | ↓total C, ↓LDL-C ↑HDL-C, ↑HDL:LDL ratio ↓TG (compared to SA diet) ↓apoB, ↑apoA1:apoB ratio |
| Mensink et al. (1992) [48] | Intervention trial | 58 total 27 males 31 females |
Young (specific ages not stated) | 53 days | 17 d on a diet high in SFA (19.3% E; primarily PA and SA), followed by 36 d on a diet replacing 6.5% total E from SFA with MUFA (15.1% E; 14.5% E OA) or PUFA (12.7% E; 12.6% E LA) diets. | ↔Lp(a), ↑LDL-C (compared to MUFA diet) |
| Mensink et al. (1992) [48] | Intervention trial | 56 total 26 males 30 females |
Young (specific ages not stated) | 3 weeks | SA diet (11.8% E), LA diet (12% E), or TFA diet (7.7% E). | ↔Lp(a) (compared to SA diet) ↓Lp(a) (compared to TFA diet) ↓LDL-C |
| Sola et al. (1997) [42] | Randomized crossover |
22 males | Mean, 49.7 (SE, ± 0.6 years) | 32 weeks | Stabilization period for 8 wk, followed by two 8 wk dietary treatments separated by an 8 wk washout period. The dietary treatments included a diet rich in OA (18.2% E MUFA) and one rich in LA (18.1% E PUFA). | ↑oxidized HDL3, ↔total C, ↔LDL-C ↔HDL2-C, ↔HDL3-C ↔TG, ↔apoB ↓apoA1, ↓apoA2 |
| Sanders et al. (1997) [35] | Randomized crossover |
26 males | 18–34 years | 17 weeks | 3 wk of a SFA diet (16% E SFA; mostly PA and SA), followed by 3 wk of an n-3 diet (1.5% E EPA and DHA or 5 g/d) or an n-6 diet (1.5% E LA or 5 g/d), separated by an 8 wk washout period. | ↑TG, ↑HDL3-C, ↑apoA2 ↓HDL2-C (compared with n-3 diet) ↓total C, ↓LDL-C, ↓apoB ↑Lp(a) (compared with SFA diet) |
| Pang et al. (1998) [44] | Randomized single-blinded |
29 males | 18–35 years | 8 weeks | After a 2 wk stabilization period, the subjects followed either an ALA-rich diet (10.1 g/d, 3.5% E ALA and 12.1 g/d, 3.1% E LA; ALA:LA ratio of 1:0.9) or an LA-rich diet (1 g/d, 0.1% E ALA and 21 g/d, 6.7% E LA; ALA:LA ratio of 1:66) for 6 wk. | ↔total C, ↔LDL-C ↔HDL-C, ↔HDL2-C ↔HDL3-C, ↔TG |
| Wagner et al. (2001) [36] | Randomized double-blinded crossover |
28 males | 19–31 years mean, 23.7 years | 11 weeks | After 2 wk of adjustment, the subjects consumed 80 g/d PUFA-rich corn oil (11.3% E LA and 9.6% E OA) or 80 g of a MUFA-rich mixture of olive and sunflower oils (5.7% E LA and 13.6% E OA) for 2 wk. | ↓total C (after crossover; compared with MUFA-rich mixture) ↓LDL-C, ↓TG, ↓VLDL-TG ↓VLDL-C (after initial 2 wk) ↔HDL-C |
| French et al. (2002) [38] | Intervention trial | 3 males 3 females |
Mean, 25 years | 8 months | The subjects consumed 8 different diets for 21 d each, with a break of 7 d between diets. The diets provided 10% E PA, with levels of LA starting at 10% E and gradually decreasing to 2.5% E. | ↓total C, ↓LDL-C (from 4.5% E to 10% E LA; 10% E LA produced the lowest LDL-C) ↓HDL-C (from 2.5% E to 10% E LA; 2.5% E LA produced the highest HDL-C) |
| Goyens et al. (2005) [40] | Randomized double-blinded | 21 males 33 females |
Males: mean, 52.6 years (SD, ± 13.7) Females: mean, 47.7 years (SD, ± 11.1) |
10 weeks | Following a 4 wk run-in period, 18 subjects per group consumed a control diet (7% E LA and 0.4% E ALA, ALA:LA ratio of 1:19), low-LA diet (3% E LA, 0.4% ALA) or high-ALA (7% E LA, 1.1% E ALA). Both treatment diets had an ALA:LA ratio of 1:7. | ↓total C,↓LDL-C, ↓apoB ↓total:HDL cholesterol ratio (High-ALA group compared with control) ↔HDL-C, ↔apoA1 ↔TG (all groups) ↓medium VLDL (Low-LA group compared with control) ↓small VLDL (High-ALA group compared with control) |
| Thijssen et al. (2005) [43] | Randomized crossover | 18 males 27 females |
28-66 years mean, 51 years (SD, ± 10) |
17 weeks | Each participant consumed each diet for 5 wk, with a washout period of ≥ 1 wk. The diets did not differ, except for the replacement of 7% E with SA, OA, or LA. | ↔total C, ↔LDL-C ↔HDL-C, ↔TG ↔apoA1, ↔apoB ↔total:HDL cholesterol ratio ↔lipoprotein particle sizes (all diets compared) |
| Liou et al. (2007) [46] | Randomized crossover | 22 males | 20–45 years mean, 27.9 years (SEM, ± 1.1) |
10 weeks | Following a 2 wk phase without consumption of fish and seafood, each subject consumed the high LA diet (10.5% E LA; LA:ALA ratio of ~10:1) and the low LA diet (3.8% E LA; LA:ALA ratio of ~4:1) for 4 wk each. ALA was maintained at ~1% E for each diet. | ↔total C, ↔LDL-C ↔HDL-C ↔LDL:HDL cholesterol ratio, ↔TG |
| Damsgaard et al. (2008) [45] | Randomized double-blinded |
64 males | 19–40 years | 10 weeks | Following a 2 wk run-in period, the participants consumed fish oil capsules (3.1 g/d n-3 LC PUFA; 1.8 g/d EPA, 0.2 g/d DPA, and 1.1 g/d DHA) or olive oil capsules (3.7 g/d OA) for 8 wk. Within each group, the subjects consumed either a low-LA diet (12.7 g LA/100 g fats or 4% E LA) or a high-LA diet (40.3 g LA/100 g fats or 7% E LA; 7.3 g/d higher LA). | ↓TG (fish oil groups compared with olive oil groups; TG decreased by 51% in the low-LA group compared to a decrease of 19% in the high-LA group; not significant) ↔total C, ↔LDL-C ↔HDL-C |
| van Schalkwijk et al. (2014) [37] | Randomized double-blinded crossover |
12 males | 30–60 years mean, 51 years (SD, ± 7) |
12 weeks | A supplement spread of 60 g/d MCFA (65% C8:0 and C10:0) or LCFA (71% LA) for 3 wk, with a washout period of 6 wk between treatments. | ↓total C, ↓LDL-C ↓VLDL-C, ↓TG ↓LDL-TG, ↓VLDL-TG |
| Dias et al. (2017) [47] | Randomized Intervention trial |
6 males 20 females |
18–65 years | 6 weeks | A SFA-rich diet (18.9% E SFA and 2.9% E LA) or an n-6 PUFA-rich diet (12.6% E SFA and 12.7% E LA) for 6 wk. Each diet was supplemented daily with 400 mg EPA + 2000 mg DHA. | ↔total C, ↔VLDL-C ↔LDL-C, ↔ HDL-C ↔VLDL-TG, ↔total TG (no difference between diets; however, both diets reduced VLDL-C, VLDL-TG and total TG) |
Abbreviations: ALA, alpha-linolenic acid; apo, apolipoprotein; C, cholesterol; d, days; DHA, docosahexaenoic acid; DPA, docosapentaenoic acid; E, energy; EPA, eicosapentaenoic acid; HDL, high-density lipoprotein; LA, linoleic acid; LCFA, long-chain fatty acid; LDL, low-density lipoprotein; Lp, lipoprotein; MCFA, medium-chain fatty acid; MUFA, monounsaturated fatty acid; OA, oleic acid; PA, palmitic acid; PUFA, polyunsaturated fatty acid; SA, stearic acid; SFA, saturated fatty acid; TFA, trans-fatty acid; TG, triglyceride; VLDL, very-low-density lipoprotein; wk, weeks; ↑, increase; ↓, decrease; ↔, no significant difference between groups.