High blood sugar levels may lead to dementia.

A study conducted by German researchers have found that people with high blood sugar levels performed badly on memory tests compared with those with lower blood sugar.

The research was conducted with 141 participants of an average age of 63, who did not have type 2 diabetes or pre-diabetes.

The participants had to undergo a blood sugar examination and complete a series of memory tests.

The researchers also took note of the size of each participant’s hippocampus area, which plays an important role in memory.

Researcher Agnes Flöel of Charité University Medicine in Berlin says she and her colleagues found that people who had higher long-term blood sugar levels had difficulty recalling words.

She says this "correlated long-term blood-sugar levels with the number of words people could recall on a memory test."

"We also found that people with higher blood-sugar levels had smaller volumes in the size of their hippocampus," she says.

The findings were reported in the medical journal Neurology, published by the American Academy of Neurology, adds that with this research, lowering blood sugar levels may prevent memory problems in the future.

However, Flöel points out that the study was conducted on a small scale and does not prove cause and effect.

There's a need for large clinical trials to test whether lowering glucose will help with the prevention of dementia, she says.

Robert Ratner, the chief scientific and medical officer for the American Diabetes Association, says that this study at least shows an “association. They are looking at a single glucose level in time and memory. They haven't shown that the memory loss is either due to the higher glucose level, or that lowering glucose would improve memory."

He says, "It’s not surprising that glucose levels can potentially have these kinds of negative impacts. The risk of dementia is higher in people with diabetes.

"It has been well established that elevated glucose impacts brain function and recovery in people following a stroke,"

Keith Fargo of the Alzheimer’s Association says that when the body loses its ability to regulate glucose levels in the blood, the brain will not work as well as it should.

Research done by Senior Research scientist, Rachel Whitmer, shows that people with type 2 diabetes who have poor blood-sugar control are at a greater risk of dementia.

"Elderly people with type 2 diabetes are almost twice as likely to develop dementia."

Prevention is better than cure- so how do you lower your blood sugar levels if you are in the normal range?

Ratner says this is due to “genetics, diet and hormonal response.

For those who have perfectly normal glucose metabolism, there is little they can do to change their level. The body controls glucose very tightly. The body is that good."

If you want to keep your blood sugar in a healthy range, that doesn't mean "you should never eat sugar," he says.

This means a healthy diet of a reasonable number of calories and balanced protein, fat and carbohydrate intake, he says.

Exercise is also important, because it will help improve the body’s ability to utilize insulin, making a person more insulin-sensitive.

Adds Whitmer: "We know people who live an active lifestyle and eat a healthy diet are less likely to get type 2 diabetes and dementia. Having a healthy lifestyle is good for the brain."