February 21, 2012
Chronic Stress Associated With Shorter Telomeres
A pair of studies find a connection between stress and cellular aging as measured by lengths of telomeres. Chromosomes have telomere caps which are special sequences of DNA which get shorter as cells divide. Short telomeres interfere cell division and therefore make the body less able to do repairs. First, women who felt most threatened by the prospect of stressful tasks have shorter telomeres.
The ability to anticipate future events allows us to plan and exert control over our lives, but it may also contribute to stress-related increased risk for the diseases of aging, according to a study by UCSF researchers.
In a study of 50 women, about half of them caring for relatives with dementia, the psychologists found that those most threatened by the anticipation of stressful tasks in the laboratory and through public speaking and solving math problems, looked older at the cellular level. The researchers assessed cellular age by measuring telomeres, which are the protective caps on the ends of chromosomes. Short telomeres index older cellular age and are associated with increased risk for a host of chronic diseases of aging, including cancer, heart disease and stroke.
My advice: Live lower stress lives.
Depressed people suffer from chronic stress and shorter telomeres.
Scientists of a new study published this week in Biological Psychiatry sought to bring all this prior work together by studying the relationships between telomere length, stress, and depression.
They did so by measuring telomere length in patients with major depressive disorder and in healthy individuals. They also measured stress, both biologically, by measuring cortisol levels, and subjectively, through a questionnaire.
They found that telomere length was shorter in the depressed patients, which confirmed prior findings. Importantly, they also discovered that shorter telomere length was associated with a low cortisol state in both the depressed and healthy groups.
First author Dr. Mikael Wikgren further explained, "Our findings suggest that stress plays an important role in depression, as telomere length was especially shortened in patients exhibiting an overly sensitive HPA axis. This HPA axis response is something which has been linked to chronic stress and with poor ability to cope with stress."
My advice: conduct your life in ways that reduce the risk you'll find yourself in stressful situations. Also Always Look On The Bright Side of Life.
I think that the goal of living a lower stress life (I have chosen this) is often in direct conflict with the goal of maximising your income and career prospects. Lawyers in big law firms earn big buck but in my experience they all to a greater or less extent suffer from high stress - there is the demand to get the work done in a 24/7 email/blackberry culture, the risk of an error which will cost the bucks, the knowledge that people only care about how much you've billed in the last 6 months and couldn't care less about past contributions, and staff hastles. A lot of lowly paid occupations are probably highly stressed (social worker?) but there are not many highly paid occupations that are low stress.
Improved cognitive function may result in an unimpeded view of reality, to your ultimate detriment.
Exercise caution when you exercise.
I would read the first as suggesting not necessarily a lower stress life, but training yourself (and children) with the ability to deal with stress. [recognizing that some stress, say war, is best avoided period]
This could be an artifact.
Depression and stress are correlated with high calorie diets.
The empty-calorie comfort foods may be responsible.
As stated above, there could be a third factor causing both the shorter telomeres and the negative emotions. This could be bad diet, lack of exercise, genetic factors, etc. Also, the shorter telomeres could be causing our brains to age in a way which causes them to be less successful at handling stress and/or more susceptible to depression.
If measuring telomeres is reasonably cheap and noninvasive, a study tracking a thousand people or more over a decade or so could tell us whether stress-causing events, such as the death of a spouse, cause telomere shortening. I'd also be interested in seeing whether Presidents, who famously age more than one might expect in 8 years, lose more telomeres during their term of office than do other people.
In other words, empty-calorie comfort foods cause one to eat empty-calorie comfort foods.
A downward (and outward) spriral
very skeptical of every physical condition, 'especially' at the cellular level, that are attributed to psychological factors.
in many cases, it needs to be turned around to physical conditions causing a psychological outcomes. not sure it applies in the above case, but I'll take this one with a grain of salt.
how many people are prescribed psychotropic meds, before a full physical examination is made?
i fear we lean too much on psychology, because it can never actually be wrong, at least relative to our understanding of our phsyiology, where we accept that there are so many things we just don't know.
would love to see a long term study with vegans...
they hit 40, and wake up looking like 60.
(there are exceptions, but this seems to be the case for most.)
should have included one of my favorite examples, in the above...
SSRI...Selective serotonin reuptake inhibitor, eveybody is on them, or knows someone who is on them. they come in 53 'flavors'.
ask them, or oneself, if they got their serontin levels checked when the meds were prescribed. how often does one go in to recheck the serotonin levels, to see if the 'levels' are 'better'?
Since the author of this study also recently published -
"Dynamics of telomerase activity in response to acute psychological stress"
- which measured telomeres/telomerase activity in immune cells, the most current study probably does also.
T-lymphocytes telomere length varies over time, so may not really reflect an intrinsic aging rate.
To add to the confusion, the stress hormone, cortisol, is raised in calorically restricted lab animals, but they live longer.
I believe cortisol increases the number of population doublings when added to cell cultures - maybe slowing cellular aging?
mark I. - the jury is out on SSRIs. For example, see -
"Increased Fracture Risk and Psychotropic Medications"
"the jury is out on SSRIs..."
I love your phrasing. the concept of a jury is more apt in the field of psychology than any other 'science'. considering that the jury is paid by the actual industry which wants to market their drugs...no bias there.
my skepticism allows for the possiblity that ssri are wonderful, in some, as yet undefined, statistical way.
the broad theme though, is that I get queezy when someone uses liberal arts witchcraft to validate a legitimate scientific endeavor.
psychology isn't just seeing what one wants to see, it also includes ignoring things that are patently obvious. take zyprexa/olanzipine...
find a kid, 90% of the time they will be male, who is on the med. observe their belly. there is a characteristic swollen pot belly, abnormal from the usual pot belly, consistent with what appears to be a liver at twice it's normal size.
despite my indictment of psychology and psychiatry, there have been brilliant men in the field.
milgram and zimbardo(even though he is a crazy loon). they see it for what it is...or, they see man, for what we are.
Mark, I believe checking the Serotonin levels would require a brain biopsy, I don't believe you can measure the blood levels but I could be wrong.
I was recently diagnosed with a fatty liver. I'm working in Afghanistan and have no access to alcohol. I had suspected it and asked my Doctor in the states to check for this, however she did not. So I had an ultrasound out here, and guess what? Fatty liver. I'm only about 15 pounds overweight at this point, not sure how that's happened! NAFLD, I suppose.
I wonder if it's possible that the large amounts of depression are a result of fatty liver problems. I wouldn't doubt it, I've read up on it and it apparently allows toxins to float around in your system which should have been cleaned up.
Possibly due to the combined biological burden of hundreds of chemicals which never existed in nature, yet we are now born with? Or simply lifestyle issues? Probably a combination.
Speaking of SSRI's and memory loss, there seems to be a fair amount of anecdotal evidence linking the two.