Another new day, another new year – another good time to consider what you can do to improve not just the quantity, but also the quality of your years on this planet.

You could resolve to be more stressed. No, that isn’t an error, and yes, I meant to write more, not less, stressed.

Doctors have been droning on about how bad stress is for your health for so many years now that you probably don’t hear it any longer.

Of course they are right in some cases, but not always. Doctors, bless their little, mostly good hearts, are not always right. They are not gods. They are not perfect founts of wisdom about good health and how best to achieve it.

And much as they love to believe they practise the science of medicine, they practise the art of medicine just as much. And their prescriptions don’t come with a one-size-fits-all label.

A growing body of scientific research is proving that you can – and should – ditch the idea that biology is destiny and that your genes mostly dictate your health.

Environment and lifestyle habits are proving to be far more important keys to longevity. And along the way, that research is proving that stress is not by definition bad for you.

Studies support the intriguing notion that small doses of “stressors”, including poison, radiation and heat, would you believe, can be beneficial. It’s due to the “hormesis” effect, defined on the US National Institutes of Health’s website as:

“a term used by toxicologists to refer to a biphasic dose response to an environmental agent characterised by a low dose stimulation or beneficial effect and a high dose inhibitory or toxic effect”.

In the fields of biology and medicine, the site continues, hormesis is defined as “an adaptive response of cells and organisms to a moderate (usually intermittent) stress”.

Hormesis used to be considered the preserve of weirdos, but these days, reputable scientists are saying it can reverse the ageing process. They say that’s because a little bit of stress appears to kick-start the body’s natural repair mechanisms, to repair any damage it may have caused. As long as the damage isn’t too severe, so the theory goes, the repair systems go overboard by repairing damage (including to DNA) the stressor (or stressors) didn’t do.

Apparently there is already indirect evidence of the positive effects of hormesis on human longevity.

A New Scientist report in 2006, for example, refers to research between 1980 and 1988 by US scientists at John Hopkins University Medical School who tracked 28,000 nuclear shipyard workers to study the effects of low doses of radiation.

“To their surprise”, the report says (I’d say that was putting it mildly, and was more like to their “absolute amazement”) , the researchers found the mortality rate of these workers to be 24% lower than in a control group of 32,500 shipyard workers of similar ages who were not exposed to radiation.

The New Scientist article refers to other research showing that “feeding fragments of DNA to elderly human cells grown in culture, which mimics the effect of DNA damage, restores their DNA repair capabilities to levels usually seen only in youthful cells”.

Thankfully, the article also says you don’t have to – and certainly shouldn’t – expose yourself to dangerous radiation or noxious chemicals to benefit from hormesis. That isn’t something you should try on your own at home, as radiation exposure has documented and horrifically negative effects. And you might not get the dose just right to turn radiation’s normally harmful effects into healing.

Instead, you could just try eating eat less – much, much less. Extreme calorie restriction – usually a euphemism for near-starvation diets – is proving to be a sufficiently low-level stressor to boost longevity.

The calorie restriction needs to be really extreme – not just halving the massive portions all the fatties in South Africa and other countries wolf down on a regular basis.

If eating too little sounds like too big a stressor to you, there are other, slightly more pleasurable ways to trick your body’s repair mechanisms into overcompensating.

One of them is exercise. Once again, you need to get the dose right. Too much exercise can be as bad as too little.

If you are not much of a fan of exercise, then you could just take to your bed – or stay on the couch – and get deep sleep. It has been described as “probably the most important longevity secret”.

Tags: #Longevity, diet, eating, sleep, stress