Eating lots of carbs, sugar may raise risk of cognitive impairment, study finds

October 16, 2012, Mayo Clinic

People 70 and older who eat food high in carbohydrates have nearly four times the risk of developing mild cognitive impairment, and the danger also rises with a diet heavy in sugar, Mayo Clinic researchers have found. Those who consume a lot of protein and fat relative to carbohydrates are less likely to become cognitively impaired, the study found. The findings are published in the Journal of Alzheimer's Disease.

The research highlights the importance of a well-rounded diet, says lead author Rosebud Roberts, M.B., Ch.B., a Mayo Clinic epidemiologist.

"We think it's important that you eat a healthy balance of protein, carbohydrates and fat, because each of these nutrients has an important role in the body," Dr. Roberts says.

Researchers tracked 1,230 people ages 70 to 89 who provided information on what they ate during the previous year. At that time, their cognitive function was evaluated by an expert panel of physicians, nurses and . Of those participants, only the roughly 940 who showed no signs of cognitive impairment were asked to return for follow-up evaluations of their cognitive function. About four years into the study, 200 of those 940 were beginning to show , problems with memory, language, thinking and judgment that are greater than normal age-related changes.

Those who reported the highest carbohydrate intake at the beginning of the study were 1.9 times likelier to develop mild cognitive impairment than those with the lowest intake of carbohydrates. Participants with the highest were 1.5 times likelier to experience mild cognitive impairment than those with the lowest levels.

But those whose diets were highest in fat—compared to the lowest—were 42 percent less likely to face cognitive impairment, and those who had the highest intake of protein had a reduced risk of 21 percent.

When total fat and were taken into account, people with the highest carbohydrate intake were 3.6 times likelier to develop mild cognitive impairment.

"A high could be bad for you because carbohydrates impact your glucose and insulin metabolism," Dr. Roberts says. "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."

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2 comments

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droid001
1 / 5 (1) Oct 16, 2012
"Those who consume a lot of protein and fat relative to carbohydrates"
How many is a lot?
ziphead
not rated yet Oct 17, 2012
"Those who consume a lot of protein and fat relative to carbohydrates"
How many is a lot?


Human brain requires roughly 100-150 grams of glucose a day, and it cannot utilize anything else but.

If you take much less than 100-150 grams of carbs a day, body will have to decompose some of the protein, extract amino acids from it to synthesize minimum amount of glucose required; other tissues will switch to fat utilization only.

If you take significantly more than 100-150 grams of carbs a day, excess glucose damages proteins in your body, sends signals via insulin and other pathways that that it is a glut time; all your tissues start utilizing glucose ( => possibly more radical damage), your fat cells start to deposit fat.

To give you an idea; 2 big slices of bread contain I think about 100 grams glucose.

There is no new science here really; just reconfirming the good old truths.

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