Studies have shown that a diet high in carbohydrates make the chance of developing Mild Cognitive Impairment, or MCI, 4 times greater in the elderly. MCI is a precursor to Alzheimer’s. Studies at Mayo Clinic are showing the same results with sugar.
Not everyone with MCI develops Alzheimer’s, but a large percentage do, according to Rosebud Roberts, professor of epidemiology at Mayo Clinic. Studies have shown that a diet high in carbohydrates may contribute to the growth of beta amyloid plaques, proteins found in the brains of people with Alzheimer’s.
Approximately 6% of elderly people develop MCI, of these 10-15% will develop Alzheimer’s. Alzheimer’s disease is the cause of death of about 60,000 in the UK each year according to the Alzheimer’s Society.
Early identification of MCI is crucial, early treatment has a much higher success rate. The Mayo Clinic research studied 1230 people aged 70-89 with specific information on what they had eaten in the last year. 940 people with no cognitive impairment were asked to return every 15 months, by the 4th year 200 of the 940 were exhibiting signs of MCI, with problems with memory, language, thinking, and critical judgment skills.
Compared to people with low carbohydrate diets, those with a high carbohydrate diet were 3.68 times more likely to develop MCI. “If we can stop people from developing MCI, we hope we can stop people from developing dementia. Once you hit the dementia stage, it’s irreversible,” Professor Roberts told USA Today. “A high-carbohydrate intake could be bad for you because carbohydrates impact your glucose and insulin metabolism.
Sugar fuels the brain, so moderate intake is good. However, high levels of sugar may actually prevent the brain from using the sugar – similar to what we see with type 2 diabetes.”
The diets highest in “good fats” such as nuts and healthy oils, and high in lean protein, showed the least occurrence of MCI and Alzheimer’s disease. Carbohydrates like fruits and vegetables do not show the same spike in blood sugar levels as breads and cereals.