Stress and Depression Shorten Telomeres, Life Expectancy

Telomere length has been linked with a greater risk of early mortality. This means dying sooner. Now research finds that children who have stressful and unstable family environments will have reduced telomere length.

What are Telomeres?

Telomeres are at the end of each chromosome, and each time a cell divides, the telomeres become shorter. Because our life span is connected to how many times our cells can divide, shorter telomeres mean fewer cell division and a shorter life expectancy.

However, research over the past two decades has also found that other factors outside of cellular division shorten telomere length. These include toxins, diet and other factors. Now we find a child’s family environment will help determine telomere length.

‘Harsh’ Families Reduce Telomere Length

The study, published in the Proceedings of the National Academy of Sciences, comes from Princeton University and the University of Michigan. The researchers studied 40 African American boys who were aged nine and part of the Fragile Families and Child Wellbeing Study. Half of the children were raised in families that had more instability, less family structure – such as breakups between parents – and were subjected to more severe punishment. Most were also from low-income families. These were identified as ‘disadvantaged’ children with ‘harsh environments.’

The other 20 children were from “advantaged” environments – which means they had more stable families with better parenting quality – meaning not subjected to harsh punishments and many other stress factors. The families of these children were identified as being ‘nurturing environments.’

The research discovered that boys in ‘disadvantaged’ and ‘harsh’ family environments had an average of 19% shorter telomere length compared with children from the ‘advantaged’ and ‘nurturing’ family environments.

But when family stability was separated from the other factors, it was found that those boys with multiple changes in family structure – such as multiple partners, divorce or moving between parents – had a 40% reduced telomere length compared to the boys with more stable families.

Shorter telomere length was also associated with less household income and single mothers. And having a mother who graduated from high school resulted in an average of 32% longer telomere length.

Stress linked to shorter telomere length

Research from The Netherlands’ Vrije University confirmed that increased stress will  also reduce telomere length. The researchers followed 2,936 adults as part of the Netherlands Study of Depression and Anxiety. The research found those with higher markers of physiological stress – such as interleukin-6 (IL6), c-reactive protein (CRP), tumor necrosis factor-alpha (TNFa), and cortisol factors – had decreased telomere length.

The researchers calculated that those in the highest quartile (highest 25%) of these stress markers had lower telomere lengths that corresponded to a lifespan reduction (and faster aging) of about ten years.

Depression also produces shorter telomere length

Another study from the VU University Medical Center found that depression produced shorter telomere length as well. This study tested 1,095 adults diagnosed with major depression, 802 patients in remission from depression, and 510 healthy control volunteers.

This study found that the longer and more severe the depression, the shorter the telomere length. Those with severe depression lasting longer than four years showed the shortest telomere lengths.

Even those with a past depression, even after recovery, had shorter telomere lengths compared to the healthy controls with no depression history.

Toxins also decrease telomere length

Other studies have linked toxins and other disease factors with telomere length, and studies have related tough childhoods with increased depression. In another article, we showed how pesticide exposure decreases telomere length.

The science is pulling together the relevant facts showing that our future relates directly to not only how we treat our bodies, but how we treat each other. An unstable family environment with stress and violence leaves an indelible mark upon the children of that family – not just emotionally, but relating to their future physical well-being.

Food for thought for all parents.

REFERENCES:

Mitchell C, Hobcraft J, McLanahan SS, Siegel SR, Berg A, Brooks-Gunn J, Garfinkel I, Notterman D. Social disadvantage, genetic sensitivity, and children’s telomere length. Proc Natl Acad Sci U S A. 2014 Apr 22;111(16):5944-9. doi: 10.1073/pnas.1404293111.

Révész D, Verhoeven JE, Milaneschi Y, de Geus EJ, Wolkowitz OM, Penninx BW. Dysregulated physiological stress systems and accelerated cellular aging. Neurobiol Aging. 2014 Jun;35(6):1422-30. doi: 10.1016/j.neurobiolaging.2013.12.027.

Verhoeven JE, Révész D, Epel ES, Lin J, Wolkowitz OM, Penninx BW. Major depressive disorder and accelerated cellular aging: results from a large psychiatric cohort study. Mol Psychiatry. 2013 Nov 12. doi: 10.1038/mp.2013.151.