Impact of Fatty Acid Supplementation on Cognitive Performance among United States (US) Military Officers: The Ranger Resilience and Improved Performance on Phospholipid-Bound Omega-3’s (RRIPP-3) Study

Nutrients
Q1
May 2021
Citations:18
Influential Citations:1
Interventional (Human) Studies
84
S2 IconPDF Icon

Enhanced Details

Methods
Double-blind, randomized, placebo-controlled trial of 555 healthy US Army IBOLC officers (mean age 23.4 ± 2.8 years; 98.6% male) entering Ranger Course after IBOLC. Participants were randomized to krill oil or macadamia nut oil; cognitive, resilience, and mood outcomes were assessed at baseline, mid-study (≈14 weeks), and after Ranger Course (≈16 weeks).
Intervention
Krill oil concentrate capsules delivering approximately 2.3 g/day omega-3s (EPA:DHA ≈ 2:1), administered as 8 capsules daily for about 20 weeks during IBOLC; identical-appearing placebo capsules contained macadamia nut oil; dietary supplements provided only during IBOLC and not during Ranger Course.
Results
Krill oil supplementation did not improve cognitive performance, resilience, or mood compared with placebo in healthy young military officers during IBOLC and Ranger Course. Primary cognitive outcomes (Stroop Color‑Word Inhibition test and Symbol‑Digit Modalities Test) showed no significant group-by-time differences; resilience and mood measures likewise showed no treatment effects. Ranger Course graduation rates did not differ between groups (p = 0.8319). Hypotheses for real-world visuospatial planning and visuomotor control could not be tested adequately due to changes in scoring during the study. Overall, there is no evidence that krill oil omega-3 supplementation enhances cognitive performance or operational readiness in this setting.
Limitations
High attrition (~44% completion) and compliance variability; some real-world outcome measures were not consistently collected due to scoring changes; possible capsule-sharing and nonadherence; limited generalizability to young, healthy military personnel; potential underpower to detect small effects.

Abstract

Studies have assessed omega-3 fatty acids and cognitive decline among older adults and cognitive development among children, although less is known about cognitive or neurological effects among young adults. We examined whether omega-3 supplementatio...