Rising incidence of tooth decay and other orthodontic conditions among children have led to increasing use of dental surgery. The use of local anaesthetic during surgery may affect tooth cell growth and the development of children's teeth, according to a new study by an international team of researchers from China, Switzerland and Britain. Using pig teeth and human young permanent tooth pulp cells, the study found that local anaesthetics commonly used in clinics can affect the proliferation of tooth cells. Longer durations of exposure to high concentrations of local anaesthetic was most harmful because it interferes with the function of mitochondria, the "batteries" of the cell, and induce a cell death mechanism known as autophagy. While the study has identified a potentially harmful effect of local anaesthetic on developing teeth, the research team emphasises that further clinical studies are required before there is enough data to change clinical guidelines, and that parents should not be alarmed or withdraw their children from treatment if they need it.

For better cardiovascular health, check your gut. Bacteria living in your gut may affect your weight, fat and good cholesterol levels, factors necessary to help maintain a healthy heart, according to new research in the journal . Using state-of-the-art deep sequencing technology, researchers from University Medical Centre Groningen studied the association between gut microbes and blood lipid levels in 893 people in the Netherlands. They identified 34 different types of bacteria that contributed to differences in body fat and blood lipids such as triglycerides and good cholesterol (or HDL). Gut bacteria contributed to 4.6 per cent of the difference in body fat, 6 per cent in triglycerides and 4 per cent in HDL. However, gut bacteria had little relationship with bad cholesterol (LDL) or total cholesterol levels. The researchers believe these findings may lead to new therapies to alter the gut bacteria types that contribute to body weight, fat and cholesterol levels to help aid in the prevention of heart disease.

Some people believe that weight is unchangeable and determined by DNA. It's highly debatable, but a new study finds that those who believe so have less healthy body mass indexes, make poorer food choices, and report lower levels of personal well-being than those who don't. Analysing data from both medical and self-reported health measurements of nearly 9,000 men and women, the study in the journal found that as people get older, the belief that weight is beyond their control is associated with less healthy eating behaviour, less exercise, and consuming more frozen, restaurant and ready-to-eat foods. "By fighting the perception that weight is unchangeable, health care providers may be able to increase healthful behaviour among their patients," say study authors Dr Mike C. Parent and Dr Jessica L. Alquist.