Table 1 Effects of CLA supplementation on inflammation and oxidative stress parameters in human studies
Author (year) | Country (Reference number) | Study design (sex) | Participants numbers (intervention/placebo) | Type and (dose) of CLA administered | Duration (mean age of subjects), [Health status] | Outcome measures |
|---|---|---|---|---|---|---|
Turpeinen et al. (2008) | Finland [57] | RCT (M/F) | 40 (20/20) | CLA capsules contained 65·3% cis-9, trans-11-CLA (2 g/d) | 12-week (20–46 years) [Birch pollen allergy subjects] | IL-5 ↓ IL-6 ↔ TNF-α ↓ IFN-γ ↑ |
Eftekhari et al. (2013) | Iran [26] | RCT (M/F) | 90 (30/30/30) | Participants were divided into 3 groups receiving 3 g/d CLA (50:50 isomer blend of cis-9 trans-11 and trans-10 cis-12) or 1 920 mg/d ω3 or placebo | 2-month (54.3 years) [Atherosclerotic patients] | hs-CRP ↓ MDA ↓ GPx ↑ IL-6 ↔ |
Risérus et al. (2002) | Sweden [50] | RCT (M) | 60 (20/20/20) | Trans 10 cis 12 isomer of CLA (3.4 g/d) or mixture isomers of CLA (3.4 g/d) or Placebo | 12-week (35–65 years) [Metabolic syndrome patients] | CRP ↑ IL-6 ↑ TNF-α ↑ |
Ebrahimi-Mameghani et al. (2016) | Iran [59] | RCT (M/F) | 38 (19/19) | Intervention group: CLA softgel 3 g/d (isomers were not identified) + weight loss diet + 400 IU vitamin E or Control group: weight loss diet + 400 IU vitamin E | 8-week (20–50 years) [Non-alcoholic fatty liver disease patients] | MDA ↔ TAC ↔ |
Mullen et al. (2006) | Ireland [44] | RCT (M) | 30 (15/15) | 2.2 g/d CLA (50:50 isomeric of cis 9, trans 11 and trans trans 10, cis 12) or Placebo | 8-week (40–60 years) [Healthy middle-aged males] | CRP ↔ TNF-α ↔ IL-2 ↓ IL-6 ↔ IL-10 ↔ |
Sluijs et al. (2010) | Netherlands [60] | RCT (M/F) | 401 (201/200) | Participants received either 4 g CLA/d (2.5 g 9-cis, 11-trans CLA/d and 0.6 g 10-trans, 12-cis CLA/d) or placebo supplements | 6-month (40–70 years) [Overweight and obese adults] | CRP ↔  |
Joseph et al. (2011) | Canada [58] | RCT (M) | 27 (crossover) | Mixture of 3.5 g/d CLA (50:50) contain (cis 9, trans 11) and (trans 10, cis 12) or Placebo (safflower) | 8-week (18–60 years) [Hyperlipidemic overweight men] | IL-6 ↔ hs-CRP ↔ TNF-α ↔ Ox-LDL ↔ |
MacRedmond et al. (2010) | Canada [61] | RCT (M/F) | 26 (13/13) | 4.5 g/d CLA (contain mixture of cis-9, trans-11 36.4%, and trans-10-cis-12 37.0%) or Placebo | 12-week (19–40 years) [Overweight mild asthmatics patients] | IL-5 ↔ IL-6 ↔ TNF-α ↔ IFN-γ ↔ MCP-1 ↔  |
Steck et al. (2007) | USA [23] | RCT (M/F) | 48 (16/16/16) | 3.2 g/d and 6.4 g/d CLA (50:50 ratio of cis-9, trans-11 and trans-10, cis-12 isomers) or Placebo (8 g/d safflower oil) | 12-week (18–50 years) [Obese individuals] | CRP ↑ IL-6 ↑ |
Mohammadzadeh et al. (2013) | Iran [47] | RCT (M/F) | 34 (16/18) | 3 g/d CLA(contained isomers 18:2 cis 9, trans 11 and 18:2 trans 10,cis 12 in a 50/50 ratio) or Placebo (sunflower oil) | 6-week (60.4 years) [Rectal cancer patients] | IL-1β ↔ IL-6 ↔ TNF-α ↓ MMP-9 ↓ hs-CRP ↓ MMP-2 ↔ |
Smedman et al. (2005) | Sweden [49] | RCT (M/F) | 53 (28/25) | 4.2 g/d CLA(containing cis-9,trans-11 and trans-10,cis-12 isomers) or Placebo (olive oil) | 12-week (23–63 years) [Healthy human subjects] | CRP ↑ TNF-α ↔ |