Excessive shortening of the telomeric ends of chromosomes is a marker of accelerated ageing. Oxidative stress and nutritional deficiency may influence this process. We investigated the effect of omega-3 polyunsaturated fatty acid (n-3 PUFA) supplementation on telomeric shortening in elderly people with mild cognitive impairment (MCI).

Thirty-three adults >65 years with MCI were randomised to receive a supplement rich in the long-chain n-3 PUFAs EPA (1.67g EPA+0.16g DHA/day; n=12) or DHA (1.55g DHA+0.40g EPA/day; n=12), versus n-6 PUFA linoleic acid (LA; 2.2g/day; n=9) for 6 months.

The intervention did not show an increase in telomere length with treatment and there was a trend towards telomere shortening during the intervention period. Linear mixed modelling produced a robust model although statistically underpowered. Telomere shortening was greatest in the LA group (d=0.21) versus the DHA (d=0.12) and EPA groups (d=.06). Increased erythrocyte DHA levels were associated with reduced telomere shortening (r=-0.67, P=0.02) in the DHA group.

Telomeric shortening may be attenuated by n-3 PUFA supplementation, requiring further investigation in larger samples.

PMID: 24342530