People with type 2 diabetes appear to have poorer cognitive functioning, a new study has found.

Canadian researchers carried out a detailed analysis of all the available studies that investigated the link between type 2 diabetes and a reduction in cognitive abilities known as executive functioning.

Executive functioning refers to mental processes that are required to perform activities such as managing time, planning, paying attention, organising and strategising. It also inhibits certain emotional and reflexive behaviours, such as inappropriate emotional reactions and impulse purchasing.

The researchers looked at 60 studies involving almost 10,000 people with type 2 diabetes and over 69,000 without the condition. They found that those with type 2 diabetes had poorer executive functioning.

"This facet of brain function is particularly important because we rely on it when we are attempting to behave in a way that is contrary to our natural inclinations or what the environment impels us to do," commented the researchers from the University of Waterloo.

They noted that while there are many complications associated with type 2 diabetes if the condition is not properly controlled, ‘the types of behaviours that are recommended to help individuals control type 2 diabetes are all things that do not come naturally to most people'.

"Human beings have fairly reliable preferences for high-calorie foods and to resist medical routines that are inconvenient or time consuming.

"The problem is the fact that effective diabetes management relies pretty heavily on executive function. Essentially people with type 2 diabetes may be hit with the double whammy of having more need for executive control, but, possibly because of the disease's effect on the brain, less intact resources for exerting it," they said.

However, the researchers pointed out that recent studies have suggested that adults, particularly older adults, can improve their executive functioning by staying physically active and taking part in cognitively stimulating activities. Both of these have been found to strengthen the part of the brain that is responsible for self-control.

"Fortunately, there are a few things that can help optimise the brain structures that support executive function. Aerobic exercise and cognitively challenging activities, such as learning new things, solving difficult puzzles and other problem-solving activities, all help to keep your brain sharp.

"Aerobic exercise is probably the most important, however, because it has benefits to both the brain and the rest of the body simultaneously," the team added.

Details of these findings are published in the journal, Psychosomatic Medicine.