Table 7.
Main studies on the link between the omega-3 fatty acids supplementation and respiratory infections/illness in pediatric age.
| Study | Author | Study Population | Omega-3 Fatty Acids (dosage) | Results |
|---|---|---|---|---|
| Infants fed docosahexaenoic acid- and arachidonic acid-supplemented formula have decreased incidence of bronchiolitis/bronchitis the first year of life. | Pastor et al., 2006 [214] | Infants RCT |
DHA (17 mg/100 kcal) | Reduced incidence of bronchiolitis/bronchitis in the DHA+ group at 5 months (p = 0.0001), 7 months (p = 0.01), and 9 months (p = 0.01) |
| Fish oil n-3 polyunsaturated fatty acids selectively affect plasma cytokines and decrease illness in Thai schoolchildren: a randomized, double-blind, placebo-controlled intervention trial. | Thienprasert et al., 2009 [221] | Children (9–12 years) RCT |
EPA (200 mg) + DHA (1 g) | Fewer episodes (p = 0.014) and shorter duration (p = 0.024) of illness in fish oil group. TGF-β1 concentration was lower in fish oil group (p < 0.001). |
| Enteral Omega-3 Fatty Acid, γ-Linolenic Acid, and Antioxidant Supplementation in Acute Lung Injury. | Rice et al., 2011 [222] | Adults within 48 h of ARI onset RCT |
EPA (6.84 g) + DHA (3.40 g) daily | Not improving in the primary end point of ventilator-free days in patients with acute lung injury. |
| Prenatal Docosahexaenoic Acid Supplementation and Infant Morbidity: Randomized Controlled Trial. | Imhoff-Kunsch et al., 2011 [213] | Pregnant woman; a total of more of 800 infants were included in the trial. RCT |
DHA (400 mg) | At 1 month: shorter duration of cough, phlegm, and wheezing, respectively (p < 0.001). At 3 months: 14% less time ill (p < 0.0001). At 6 months: shorter duration of fever, nasal secretion, difficulty breathing, rash, and “other illness,” respectively (all p < 0.05). |
| A Phase II Randomized Placebo-Controlled Trial of Omega-3 Fatty Acids for the Treatment of Acute Lung Injury. | Stapleton et al., 2011 [223] | Adults within 48 h of ARI onset RCT |
EPA (9.75 g) + DHA (6.75 g) daily | Not reduction of biomarkers of pulmonary or systemic inflammation in patients with ALI. |
| Respiratory hospitalisation of infants supplemented with docosahexaenoic acid as preterm neonates. | Atwell et al., 2012 [215] | Infants born <33 weeks’ gestation RCT |
High DHA (∼1%) vs. standard DHA (∼0.3%) in breast milk or formula | Not reduced hospitalisation for LRTI problems in the first 18 months. |
| The effect of a 1-year multiple micronutrient or n-3 fatty acid fortified food intervention on morbidity in Indian school children. | Thomas et al., 2012 [217] | Children (6–10 years) RCT |
α-linolenic acid (900 mg) + DHA (100 mg) vs. α-linolenic acid (140 mg) | Significantly fewer episodes of URTI/child/year (relative risk (RR) = 0.88, 95% confidence interval (CI): 0.79, 0.97) in high consuming n-3 fatty acids group. Significantly shorter duration/episode of URTI (RR = 0.81, 95% CI: 0.78, 0.85), LRTI (RR = 0.91, 95% CI: 0.85, 0.97) in high consuming n-3 fatty acids group. |
| Effects of Growing-Up Milk Supplemented with Prebiotics and LCPUFAs on Infections in Young Children. | Chatchatee et al., 2014 [218] | Children (11–29 months) RCT |
Growing-up milk with addition of 19.2 mg/100 mL of n-3 LCPUFAs (EPA + DHA, 4:6) | Decreased risk of developing at least 1 infection (p = 0.03) in the active group. Trend toward a reduction (p = 0.07) in the total number of infections in the active group. |
| N–3 Long-chain PUFAs reduce respiratory morbidity caused by iron supplementation in iron-deficient South African schoolchildren: a randomized, double-blind, placebo-controlled intervention | Malan et al., 2015 [219] | Children (6–11 years) with iron-deficiency RCT |
EPA (80 mg) + DHA (420) + placebo vs Fe + EPA/DHA vs Fe + placebo vs placebo + placebo |
Iron supplementation increased morbidity (p = 0.001), mostly respiratory. Increase in morbidity caused by iron supplementation was prevented (p = 0.009) by DHA/EPA. |
| Fish Oil–Derived Fatty Acids in Pregnancy and Wheeze and Asthma in Offspring | Bisgaard et al., 2016 [216] | Pregnant women at 24 weeks of gestation; a total of 695 children were included in the trial. RCT |
2.4 g of n−3 LCPUFA (55% EPA and 37% DHA) daily | Lower risk of persistent wheeze or asthma in the treatment group (p = 0.035). Reduced risk of infections of the lower respiratory tract (p = 0.033) in the treatment group |
ARI, acute respiratory infection; CI, confidence interval; DHA, docosahexaenoic acid; EPA, eicosapentaenoic acid; LCPUFA, long-chain polyunsaturated fatty acid; LRTI, lower respiratory tract infection; PUFA, polyunsaturated fatty acid; RCT, randomized controlled trial; RR, relative risk; TGF, transforming growth factor; URTI, upper respiratory tract infection.