Fatty acids and telomere length.

Purpose of review: This narrative review includes the latest clinical and preclinical evidence on fatty acid exposure and telomere length, a widely accepted hallmark of aging.

Recent findings: A large body of literature focused on n-3 (omega-3) polyunsaturated fatty acids (PUFAs). Observational studies reported beneficial associations with telomere length for self-reported consumption of n-3 PUFA-rich foods; for estimated intake of n-3 PUFAs; and for n-3 PUFAs blood-based biomarkers in most (but not all) studies involving lipidomics, a promising tool in the field. Benefits were also observed in preclinical studies using different mouse models. Regarding other lipids, inconsistent findings were observed for circulating linoleic acid, whereas inverse associations with telomere length were reported for the n-6/n-3 PUFA ratio. Finally, a study using Mendelian randomization reported that monounsaturated fatty acids and PUFAs have a positive effect on telomere length, whereas the opposite was observed for saturated fatty acids.

Summary: Evidence supporting that n-3 PUFAs might have beneficial effects on maintaining telomere length reinforce the salutary effects of these dietary fats. Approach considering the n-6/n-3 PUFA ratio is discouraged because it is sustained in the incorrect assumption that all species from the n-6 and n-3 families are functionally equivalent.