Scientists in Kazakhstan have recently reported developing a life-lengthening yoghurt drink after the country’s 72-year-old leader, Nursultan Nazarbayev challenged them to provide him with “an elixir of youth and energy” that would enable him to continue his rule. He certainly would not be the first to attempt to find an answer for the problems associated with ageing; be it the odd nip and tuck, the collagen face cream or dutifully swigging bright green antioxidant wheat and barley drinks, more and more of us are trying to find solutions for staying younger for longer. Indeed, in the last decade we have seen a boom in available products, technology and procedures that aim to either slow, reduce or even prevent the ageing process from creeping up on us.
Recent studies indicate, however, that simple dietary steps can have the potential to naturally slow biological ageing. Omega-6 and omega-3 are two families of fat that must be consumed in the diet; they play an essential role in many aspects of health including modulating immunity, regulating inflammatory pathways, brain structure and function, maintaining cardiovascular health and also, it now appears, in determining how fast our biological clock ticks by affecting part of our genes called telomeres .
Found within the nucleus of every cell, our genes are located on twisted, double-stranded molecules of DNA called chromosomes. It is at the ends of the chromosomes that the stretches of DNA called telomeres are found. These telomere ‘caps’ protect our genetic data and make it possible for cells to divide. Telomere length is regulated by the enzyme telomerase and shorter telomeres have been associated with poor health behaviours and age-related diseases . Although telomeres typically shorten with ageing, this is not inevitable as telomeres can also lengthen, with evidence emerging that blood levels of certain polyunsaturated fatty acids may be one of the factors that can prevent telomere shortening over time.
Polyunsaturated fat and telomere length
Identifying those factors that affect telomere stability is a key factor in understanding the ageing process.
The omega-6 and omega-3 polyunsaturated fatty acids have long been known to influence normal growth and development; when it comes to influencing our telomeres, the ratio of omega-6 to omega-3 in cells and tissues appears to be of major importance. Specifically, a higher omega-6:omega-3 ratio, which is common in those consuming a typical Western-style diet can have a severe and negative impact on telomere length and therefore on cell ageing as a direct result . This high omega-6:omega-3 ratio is indicative of an ‘inflammatory’ status, with telomere length linked to and regulated by exposure to proinflammatory cytokines and oxidative stress products arising from the omega-6 – arachidonic acid (AA). Inflammation triggers the production of immune cells known as T-lymphocytes, which are directly linked to telomere shortening. In addition, the oxidative stress that arises as a direct result of inflammation promotes further telomere erosion during cell division, with the additional synthesis of proinflammatory products leading to an ‘inflammatory cycle’ that effectively ‘eats away’ at our telomeres. This triad of inflammation, oxidative stress, and immune cell ageing provides a direct target for nutritional interventions. As an example, not only can the omega-6:omega-3 ratio be altered by increasing omega-3 supplementation, but also by decreasing omega-6 intake.
Understanding the omega-6:omega-3 ratio
The terms ‘omega-6’ and ‘omega-3’ relate to two families of fatty acids. Some metabolites of omega-6s are inflammatory while others are anti-inflammatory; whilst the prevalence of omega-6 in the Western diet is linked to increased inflammation, this inflammatory status is more the result of the lack of omega-3s, which are not only less inflammatory but also serve to shuttle the omega-6 down an anti-inflammatory pathway. When omega-3 fatty acids aren’t present in sufficient quantities within the diet, the body utilises the omega-6 AA-producing metabolites that drive the inflammatory response . To develop an anti-inflammatory regime, the prevention or reduction of AA accumulation must be achieved. By reducing AA we reduce the substrate for the formation of inflammatory products, lower oxidative stress and the production of T-lymphocytes, thereby buffering the ‘inflammatory cycle’. The Kazakhstan scientists may have overlooked a simple answer to their president’s demands – fish oil, or more specifically, eicosapentaenoic acid!
Is EPA the elixir of life?
Eicosapentaenoic acid (EPA) is a long-chain omega-3 fatty acid predominantly associated with fish and shellfish, and our intake of marine-sourced EPA is low in comparison to intake of omega-6-rich food. Given that the principal omega-6 and omega-3 fatty acids AA and EPA provide valuable information on the measure of the body’s inflammatory status, managing the AA:EPA ratio can offer significant long-term health benefits and reduce the risk of developing chronic low-grade inflammation. Given the concerns over contamination of many fish species with PCBs, dioxins and methylmercury, advised consumption levels fall short of the amount needed to offer therapeutic levels of EPA. Highly purified EPA supplements, in contrast, offer a safe and convenient method of achieving the high cellular levels required to reduce inflammation, lower oxidative stress and restore immune balance.
Keeping it real
Whether a leader such as Nazarbayev wishing to cling to his leadership a little longer, or Goldie Hawn’s and Meryl Streep’s characters in the 1992 film ‘Death Becomes Her’ wishing to preserve themselves for vanity’s sake, it is doubtful indeed that there will be such a product developed in any current reader’s lifetime. The idea that short telomeres predict early disease, and that disease is linked to early mortality is, however, certainly worth considering. If it is possible to slow cell ageing simply by increasing EPA and reducing AA, which could have broad effects by slowing the onset of age-related diseases, the outcome has to be food for thought.
- Kiecolt-Glaser JK, Epel ES, Belury MA, Andridge R, Lin J, Glaser R, Malarkey WB, Hwang BS, Blackburn E: Omega-3 fatty acids, oxidative stress, and leukocyte telomere length: A randomized controlled trial. Brain, behavior, and immunity 2012.
- Cassidy A, De Vivo I, Liu Y, Han J, Prescott J, Hunter DJ, Rimm EB: Associations between diet, lifestyle factors, and telomere length in women. The American journal of clinical nutrition 2010, 91:1273-1280.
- Kang JX: Differential effects of omega-6 and omega-3 fatty acids on telomere length. The American journal of clinical nutrition 2010, 92:1276-1277; author reply 1277.
- Patterson E, Wall R, Fitzgerald GF, Ross RP, Stanton C: Health implications of high dietary omega-6 polyunsaturated Fatty acids. Journal of nutrition and metabolism 2012, 2012:539426.