Many a parent has been driven to the point of madness by successive "why?" questions from preschoolers, but it's a good sign that they ask and they do better if they get a detailed explanation than if you just answer 'because.'

The American Academy of Family Physicians (AAFP), recently accepted a six-figure grant from the Coca-Cola Corporation to "educate consumers about the role their products can play in a healthy, active lifestyle," and nutrition experts from Harvard University are not very happy about the new partnership.

Satellite observations and a state-of-the art regional atmospheric model have independently confirmed that the Greenland ice sheet is loosing mass at an accelerating rate, according to a new study published in Science.

The mass loss is equally distributed between increased iceberg production, driven by acceleration of Greenland's fast-flowing outlet glaciers, and increased melt water production at the ice sheet surface. Recent warm summers further accelerated the mass loss to 273 Gt per year (1 Gt is the mass of 1 cubic kilometer of water), in the period 2006-2008, which represents 0.75 mm of global sea level rise per year.

Contrary to conservative wisdom, exercising up to the end of pregnancy has no harmful effect on the health of the mother or child, and may even be beneficial for both, indicates a study published in the International Journal of Obesity.

160 healthy women between the ages of 25 and 35 took part in the study, all of whom had sedentary habits and no risk of premature birth. Of this group of women, half followed an exercise regime under the supervision of experts in Physical Activity and Sports Science in collaboration with the Gynaecology and Obstetrics Unit of Hospital Severo Ochoa in Madrid.

A team of researchers said this week that they may have identified the genes responsible for bipolar disorder in children. Their study, published in BMC Psychiatry, implicates malfunctioning circadian clock genes, four alterations of the RORB gene to be specific, in the development of the disorder.

Scientists studied the RORA and RORB genes of 152 children with Bipolar and 140 control children. They found four alterations to the RORB gene that were positively associated with being bipolar. "Our findings suggest that clock genes in general and RORB in particular may be important candidates for further investigation in the search for the molecular basis of bipolar disorder," explained co-author Alexander Niculescu.

The controversy surrounding prescription drug advertising is immense. Advocates for prescription drug direct-to-consumer advertising (DTCA) claim that it educates consumers, improves the quality of care and contributes to better patient adherence. While opponents argue that it leads to inappropriate prescribing and portrays non-medical problems as treatable medical illnesses.

Thanks to a new paper calling for stricter federal regulation of DTCA, the policy debate over the practice is certain to intensify even more. Soon to appear in the American Journal of Public Health, the study suggests that while there are some benefits stemming from (DTCA), there are significant risks that are magnified by its prominence.