Mayo Clinic study in seniors finds that diets high in sugars and starches promote brain fog and dementia
By Craig Weatherby
Fat became public enemy number one in the 1980’s.
So fat was reduced in many processed foods, and the flavor loss was addressed by adding carbs and salt.
Why did fat get villainized so vehemently?
Fat carries twice the calories of carbs or protein, while excess saturated fat had been linked to heart disease.
As is now clear, this fat-demonization was often unfair, failed to discriminate among the various kinds of fat, and led to excess intake of carbs.
Ironically, it turns out that excess intake of carbs is likely a much greater threat … and sadly, that imbalance is now all too common.
Scrutiny puts carb-heavy diets on the spot
The term “carbs” is shorthand for carbohydrates – a category that includes fibers and sugars – but it’s usually meant to mean starch.
Starch is the rapidly-digested, nutrient-poor stuff in breads, pasta, potatoes, baked goods, and other “white” foods.
When it comes to health impacts, starches and sugars are very similar, and – when eaten to excess – about equally unhealthful.
Diets overloaded with sugars and starches promote metabolic problems that lead to diabetes and cardiovascular disease (e.g., insulin resistance, high triglyceride levels).
But it’s less well known that carb-dominated diets can also blunt your brain.
We’ve reported some intriguing research in this realm: See “Sugary Brain Damage Blunted by Omega-3s” and “Study 3: Omega-3 Shortage May Cut Brain’s Sugary Fuel Supply” in “Feel-Good Findings: Omega-3s Boost Mood, Reduce Anger, Ensure Brain’s Flow of Fuel”.
Those results dovetail with some we reported in “Blood-Starved Brains Shown Prone to Alzheimer’s”, which confirmed that when brain cells don’t get enough sugar (glucose) – due either to an extreme low-carb diet or lack of omega-3s or other nutrients needed for sugar-transport – this fuel shortage can hurt brain power.
Now, research from a Mayo Clinic team suggests that carb-soaked diets run nearly four times the risk of developing mild cognitive impairment … or, as it’s commonly called, “brain fog”.
Among more than 1,200 people aged 70 to 89, those eating the highest-carb diets were nearly four times as likely to develop mild cognitive impairment (MCI).
MCI is characterized by problems with memory, language, thinking, and judgment … mental difficulties greater than those seen with normal age-related brain changes.
Unsurprisingly, the team’s findings also linked sugary diets to a similarly high risk of losing some mental acuity.
Conversely, those who ate the most protein and fat relative to carbohydrates were much less likely to suffer a cognitive decline.
As the lead author, Dr. Rosebud Roberts, said, “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.” (MC 2012)
Study links excess carbs to fuzzy thinking
The Mayo Clinic researchers tracked 1,230 people aged 70 to 89 years (Roberts RO et al. 2012).
At the outset, the participants reported what they’d eaten during the previous year, and their cognitive function was also evaluated by an expert panel.
Of all the participants, only the 937 who showed no signs of cognitive impairment were asked to return for follow-up mental evaluations, every 15 months.
About four years into the study, 200 of those 937 began to show mild cognitive impairment (MCI) ... and the mayo team detected these correlations between diet and brain fog:
As the authors concluded, “A dietary pattern with relatively high caloric intake from carbohydrates and low caloric intake from fat and proteins may increase the risk of MCI or dementia in elderly persons.” (Roberts RO et al. 2012)
Dr. Roberts put it this way (MC 2012):
“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.”
Clearly, balance is the key to a healthful diet … not too much or too little of any one component.
You can get easily meet your brain’s fuel needs by eating lots of whole plant foods – beans, vegetables, fruits, whole grains – while minimizing refined, “white” carbs and added sugars.
Carbs Fog Aging Brains