Obesity linked to heightened sense of smell for food

By Dr. Ananya Mandal, MDNov 17 2010

New research shows that obese and overweight people have a greater sense of smell for food. The study at the University of Portsmouth explains why some people struggle to stay slim. The researchers say that it is known that part of the brain that processes information about odour is also connected to the feeding centres of the brain. This study adds to the knowledge and is published in the journal Chemical Senses.

As obesity rises worldwide this is extremely relevant. Too much food and little physical activity may be important causes but researchers are looking for deeper reasons behind the epidemic also.

Psychologist Dr. Lorenzo Stafford and his team asked 64 volunteers to take part in a series of experiments that tested their smelling ability. Findings showed that people appear to be slightly better at smelling food odours after they have eaten rather than when they are hungry. Dr Stafford explains this saying that it could be the body’s way of detecting and rejecting foods no longer needed in order to maintain the right energy balance and stop a person eating too much. Another finding showed that people who are overweight - those with a higher body mass index or BMI - have a far heightened sense of smell for food compared to slim people, particularly after they have eaten a full meal. He says that this sharper sense of smell may compel the individual to carry on eating, even when they are full.

Dr. Stafford said, “It could be speculated that for those with a propensity to gain weight, their higher sense of smell for food related odours might actually play a more active role in food intake… Hopefully this research will stimulate more work in this area with the potential to help those who struggle with their weight and those who treat people with weight problems.”