A snapshot of the current thinking in medicine, fitness and lifestyle trends that impact your lifehealth and fitness Updated: Jan 21, 2012 22:08 IST
Catch-22: Stress makes you fat, dieting is stressful
It’s a vicious cycle: Stress can make you fat, and being obese creates stress. A bad diet and lack of exercise alone is not sufficient to explain the worldwide rise in obesity. A review of a number of existing studies showed that people who had high levels of the stress hormone cortisol put on weight more easily, found US researchers.
Getting fatter potentiallys trigger the stress response, which in turn encourages additional weight gain. But dieting also stimulates cortisol production, which in turn triggers the stress response that counters weight loss. Conventional wisdom has it that eating food high in fat, salt and sugar, combined with reduced physical activity, causes obesity.
How you live impacts brain ageing
Lifestyle factors can explain why some people stay sharper in old age, say Scottish and Australian scientists. Genetic factors account for about a quarter of the changes in a person’s intelligence between childhood and later life, but it is environmental factors — such as education, occupation, relative deprivation/affluence, diet, physical and social activities and smoking — that have the most impact on how the brain ages.
Many of the genes that affect intelligence inchildhood also influence intelligence in old age, reports the Scottish study published in the journal Nature. But the largest influence was probably environmental.
Sleeplessness makes you hungry, leads to weight gain
Sleeplessness makes you eat more by affecting the brain’s perception of food, shows new research from the Uppsala University in Sweden. A specific brain region that triggers the desire to eat is more activated in response to food images after one night of sleep loss than after a night of normal sleep, showed magnetic imaging (fMRI)of the brain. This makes insomniacs gain weight over time, report researchers in The Journal of Clinical Endocrinology and Metabolism. You need seven to eight hours of sleep every night to have a stable healthy body weight.
Gossip lowers stress, promotes generosity
Haven’t got anything nice to say? Well, now you can say it anyway without guilt. Gossip may be getting an undeserved bad rap, particularly so-called prosocial gossip, which serves to warn others about dishonest or untrustworthy people — unlike the catty, idle chatter that fuels rumours.
Prosocial gossip lowered stress, prevented exploitation and promoted more generous behaviour, found psychologists at the University of California, Berkeley “Gossip can be bad, but we tend to overlook that it can be good as well,” says social psychologist Robb Willer, a co-author of the study, published in the Journal of Personality and Social Psychology. “A lot of gossip is driven by concern for others and has positive, social effects.”