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By Marika Sboros
It’s bad enough worrying about losing your marbles as you age, without thinking that what you put into your mouth could increase the risk of those marbles going missing.
Scientific evidence is there, for anyone willing to see it, to show a connection between diet and brain function in general, and dementia diseases, including Alzheimer’s, in particular. Yet there is still controversy among neurologists and other medical specialists that the link exists.
Research also shows that sugar and other high-carbohydrate foods in excess “age your brain”, and significantly increase the risk of developing a dementia disease.
If you doubt it, just ask British nutrition specialist Patrick Holford. It’s putting it mildly to say he is no fan of sugar.
In a new blog on his website, Holford says sugar, like petrol, is “dangerous stuff”. He joins other top nutrition specialists internationally, who say that while sugar is a source of the glucose your brain uses for fuel, it isn’t a good one.
Halford is a big fan of unrefined carbohydrate foods, including grains. Other specialists, among them Dr Robert Lustig, an American paediatric endocrinologist and professor of clinical paediatrics, at the University of California, San Francisco where he is a professor of clinical paediatrics, and American child and adult psychiatrist Dr Ann Childers, say carbohydrate foods are not the best for your brain. Childers says your body can make more than enough glucose to meet the brain’s needs from protein foods, and fat is the best fuel source for optimum cognitive function.
When it comes to sugar, which some Holford says the real problem with sugar – apart from the fact that it has no nutritional value whatsoever – is that when you eat it in excess, it can “literally burn your brain”.
He says the evidence is there to show that this is “exactly what happens in many people who develop Alzheimer’s”.
Holford explains the mechanism of action behind which sugar damages your brain: in excess, it forms toxic compounds called “advanced glycation end-products” (AGES); it leads to the harmful effects of too much insulin, the hormone the body releases when blood sugar levels spike.
He says you should think of glucose, or blood sugar, as “high-octane fuel”, and the goal of good nutrition as to deliver “slow-releasing” carbohydrates that gradually break down into pure glucose fuel, he says. This “seeps into the bloodstream” and is then escorted into cells to help keep your energy high.
Too much glucose overloads brain cells which are less capable of dealing with the overload than muscle cells, Holford says. This is known as “glucose neurotoxicity”, and it is backed up by studies showing higher blood glucose levels are associated with less functioning brain tissue in critical areas of the brain, he says.
“The hormone insulin escorts glucose into cells, either ensuring hungry cells get their due, or dumping excess glucose into storage,” says Holford.
“It’s a careful balancing act,” he says, “and one that’s likely to go wrong if you keep eating sugary or reﬁned carbohydrates.
“The more you eat these, the higher your insulin levels, and the more often you’ll have peaks in your blood sugar levels, followed by troughs.”
This “seesawing” will leave you tired and unable to concentrate, eventually experiencing “blank-mind” episodes and fading memory, he says. Over time, your body will become less responsive to its own insulin and will develop “insulin resistance” (IR), the precursor condition to full-blown type 2 diabetes.
What does all this have to do with preventing Alzheimer’s?
“Everything,” says Holford.
Research is there to show that IR, related conditions such as hyperinsulinema or hypoglycemia, and diabetes significantly increase the risk of Alzheimer’s. And while there are likely to be many reasons why an upset in blood sugar control damages the brain, says Holford, one stands out:
“The fact that occasional blood sugar peaks actually sugar-coat proteins, and damage them, creating damaged AGEs. A lifetime of sugar abuse, glycation (adverse interactions between glucose and proteins, for instance) and AGE creation lead to more and more artery and brain damage.
“The more the arteries become damaged, the worse the circulation to the brain and the less reliable the supply of nutrients becomes. So, ironically, eating too much sugar can lead to temporary glucose starvation to cells, as well as damage caused by excess glycation.”
And as he points out, it’s “one thing to know that sugar is bad for your brain, but another to quit eating it – especially when the desire for something sweet is one of the body’s strongest instincts”.
In evolutionary terms, Holford says, we are “all programmed to love sugar” because it releases dopamine and beta-endorphin, neurotransmitters that make you feel good. The more sugar you eat, the more you want, as you become less and less responsive to it, he says.
“In short,” says Holford, “ you become addicted to (sugar) and no addiction is easy to break.”
He quotes the late Dr Emanuel Cheraskin, Professor of Medicine at University of Alabama, who called sugar “the mother of all addiction”.
He also quotes Dr Candace Pert, Research Professor at Georgetown University Medical Centre in Washington DC, one of the chief scientists involved in the discovery of the central role endorphins play in addiction, who says: “I consider sugar to be a drug, a highly puriﬁed plant product that can become addictive. Relying on an artiﬁcial form of glucose – sugar – to give us a quick pick-me-up is analogous to, if not as dangerous as, shooting up heroin.”
- For more information on how to prevent Alzheimer’s read Holford’s Alzheimer’s Prevention Plan.
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