Asthma sufferers may be prone to bone loss
There may be a link between asthma and a decrease in bone mineral density, according to a study by South Korean researchers in the journal Annals of Allergy, Asthma & Immunology. Among more than 7,000 patients studied, 433 of whom had airway hyper-responsiveness or asthma. In people with these conditions, lumber spine and thigh bone density was significantly lower than those without the conditions. The prolonged use of corticosteroids, the most effective asthma medication, is known to be a risk factor of osteoporosis. However, the findings of this study have to be further investigated, says allergist Dr John Oppenheimer, associate editor of the journal. Reasons for bone loss could include corticosteroid use, low levels of vitamin D or even race.
Too much or too little sleep may result in worse memory in older age, finds a new study led by Brigham and Women's Hospital in Boston. Women who slept five or fewer hours, or nine or more hours per day, either in midlife or later life, had worse memory, equivalent to nearly two additional years of age, than those sleeping seven hours per day. Women whose sleep duration changed by greater than two hours per day from middle age to older age also had worse memory than women with no change in sleep duration. The study, published in The Journal of the American Geriatrics Society, involved more than 15,000 female nurses aged 70 or above.
A fattening gene
A team of researchers from Germany and Japan have discovered a gene that controls fat metabolism, possibly paving the way for the development of a drug that would prevent people becoming overweight. The researchers identified SIRT7, a gene from the sirtuin protein group that plays a major role in the utilisation of energy in a high-fat diet. They fed a high-fat diet to genetically modified mice that lacked the gene and also a control group. The mice without SIRT7 maintained their normal weight, while the controls put on significantly more weight.