The effects of a 6-month high dose omega-3 and omega-6 polyunsaturated fatty acids and antioxidant vitamins supplementation on cognitive function and functional capacity in older adults with mild cognitive impairment

The aim of the present study was to examine the effects of a high-dose omega-3 and omega-6 fatty acids supplementation, in combination with antioxidant vitamins, on cognitive function and functional capacity of older adults with mild cognitive impairment (MCI), over a 6-month period in a randomized, double-blind, placebo-controlled trial. Forty-six older adults with MCI (age: 78.8 ± 7.3 years) were randomized 1:1 to receive either a 20 mL dose of a formula containing a mixture of omega-3 (810 mg Eicosapentaenoic acid and 4140 mg Docosahexaenoic acid) and omega-6 fatty acids (1800 mg gamma-Linolenic acid and 3150 mg Linoleic acid) (1:1 w/w), with 0.6 mg vitamin A, vitamin E (22 mg) plus pure γ-tocopherol (760 mg), or 20mL placebo containing olive oil. Participants completed assessments of cognitive function, functional capacity, body composition and various aspects of quality of life at baseline and following three and six months of supplementation. Thirty-six participants completed the study (eighteen from each group). A significant interaction between supplementation and time was found on cognitive function (Addenbrooke’s Cognitive Examination-Revised (ACE-R), Mini-Mental State Examination (MMSE) and Stroop Color and Word Test (STROOP) color test; p < 0.001, p = 0.011 and p = 0.037, respectively), functional capacity (6-min walk test and sit-to-stand-60; p = 0.028 and p = 0.032, respectively), fatigue (p < 0.001), physical health (p = 0.007), and daily sleepiness (p = 0.007)—showing a favorable improvement for the participants receiving the supplement. The results indicate that this nutritional modality could be promising for reducing cognitive and functional decline in the elderly with MCI.