This post is also downloadable as a Word format handout. 

I blogged a couple of weeks ago on "Exercise 3: US Department of Health & Human Services, resources for assessment & advice" and quoted the fine 2008 "Physical activity guidelines for Americans" with its recommendation that - besides regular aerobic exercise - "People are encouraged - on at least two days per week - to strengthen the major muscle groups involving legs, hips, back, chest, stomach and shoulders.  Exercises for each muscle group should be repeated for 8 to 12 repetitions per session."

Here are half a dozen studies that one could loosely put under the broad umbrella of positive psychology.  Zorba the Greek said "Take what you want and pay for it, says God." and Niemiec et al's study, on the effects of achieving different kinds of goal, supports this statement (for all six research studies mentioned in this blog post see below for abstracts and links).  Quoting Niemiec et al's somewhat awkward language: "The relation of aspiration attainment to psychological health was found to differ as a function of the content of the goals. Attainment of the intrinsic aspirations for personal growth, close relationships, community involvement, and physical health related positively to basic psychological need satisfaction and psychological health.

Looking back over relevant research papers that caught my attention last month, some stand out for me more than the others.  Here are three on depression that stood out and got me thinking.  The Fergusson et al paper looks at links between alcohol abuse and major depression.  There has been debate for years on whether alcohol dependence leads to depression or depression leads to alcohol dependence.  In this kind of debate, it's usually a good bet that both pathways contain some truth.  What this study adds is that often it is the alcohol dependence that is primary.  As the authors state " ... the associations between AAD (alcohol abuse or dependence) and MD (major depression) were best explained by a causal model in which problems with alcohol led to increased risk of MD as opposed to a self-medication model in which MD led to increased risk of AAD." 

Here are five papers mostly looking at aspects of overweight.  The first, published recently in the Lancet, is a huge study on the effects of body-mass index (BMI) on subsequent mortality in nearly 900,000 adults.  It shows progressive excess mortality above the BMI range 22.5-25 kg/m2.  (To calculate your BMI click here).  At 40-45 kg/m2, the reduction in life expectancy of 8-10 years is comparable to the effects of being a smoker.  The second paper, by Neovius et al, also involved large numbers - over 45,000 older adolescents.  Again it showed excess mortality at long term follow-up, and commented "Obesity and overweight were as hazardous as heavy and light smoking, respectively".  The third study by Katseva et al looked at modifiable risk factors in European patients with cardiac disease.  The findings were depressing with obesity, for example, increasing stepwise from 25% at first survey, to 32.6% at second, to 38% at third survey.  Overall the authors concluded "These time trends show a compelling need for more effective lifestyle management of patients with coronary heart disease ... To salvage the acutely ischaemic myocardium without addressing the underlying causes of the disease is futile; we need to invest in prevention." 

Here are five papers on lifestyle and the benefits of making healthy choices.  The first by Cohen et al on sleep habits and susceptibility to the common cold, showed increased risk of developing a cold after infection for those with shorter sleep duration.  Interestingly the increased risk was even greater for those with poor sleep efficiency.  Sleep efficiency is calculated by dividing the time spent asleep by the time spent in bed trying to sleep.  The Good Knowledge section of this website contains useful information on assessing and treating sleep difficulties.

Fish, fish oils, and n-3 fatty acids are often in the health news.  Here are seven recent papers illustrating the breadth of fish oil relevance.  The papers look at treatment of rheumatoid arthritis, the potential of flax as a dietary source of n-3 fatty acids, effects on indicators of cardiovascular disease, potential protection against dementia, reduction in mortality, and importance in pregnancy.  The papers also illustrate the patchwork, three steps forward/one step back, meandering, spreading, accretion of scientific knowledge.  As the proverb goes "One swallow doesn't make a summer".  Similarly, a single research study is usually simply one brick in the gradual building of our knowledge.  For more on fish and n-3 fatty acids, see other relevant blog posts I've written, articles in the linked Connotea database, and some recommended websites.     

Last month's BMJ published another in the long line of research articles that highlight the huge importance of lifestyle choices for our health:

Dam, R. M. v., T. Li, et al. (2008). "Combined impact of lifestyle factors on mortality: prospective cohort study in US women." BMJ 337(sep16_2): a1440-  [Free Full Text]

It seemed time to post on recent research involving happiness and wellbeing.  Here are four studies from the current issues of the Journal of Happiness Studies (the September edition is open access with all full articles freely viewable) and the Journal of Positive Psychology.  Ad Bergsma discusses advice on how to be happy given across the ages.  He refers to some of the other articles in this edition of the Journal of Happiness studies, including papers on the happiness advice of Epicurus, Schopenhauer, and the ancient Chinese philosphers.  Maarten Berg looks at the possible value of ‘New Age' suggestions on happiness.  Paul Gilbert and colleagues look, very interestingly, at different types of positive emotion and suggest that it may be what they call "safe/content" feelings that are particulary protective against a variety of unhappy emotional states.  Veenhoven reviews thirty studies on happiness and longevity and argues that, although happiness does not seem to cure illness, it does a good job of reducing the chances of getting ill - with a similar effect size to the benefits of being a non-smoker rather than a smoker.

This week's recent research post is a mixed bag of six studies covering the physiological & psychological changes triggered by being separated from one's partner, why similar levels of anxiety & interpersonal sensitivity can lead to social anxiety in some individuals and paranoia in others, how difficulty identifying feelings is associated with increased somatization, the frequency of burnout in family doctors around Europe, personality factors that predict a longer life, and how wrong the old saying is that "Sticks & stones may break my bones, but words will never hurt me"!  

Back in January I wrote a blog post entitle "Does a healthy lifestyle really make a difference? "   I highlighted that it makes a hell of a lot of a difference.  At around that time another major study was published that hammered this point home even more thoroughly and I've been meaning to mention it in a post ever since.  The recent publicity on poor fruit and veg intake in the UK population triggered me into looking the earlier study out.