Can Sugar Effect Your Cognitive Ability?

Do you enjoy drinking soda?

Well, don’t be surprised if you start forgetting where you left your keys, because according to US scientists eating too much sugar can eat away at your brainpower. The recently published study showed how a steady diet of high-fructose corn syrup (like those found in sugar and other refined sweet treats) zapped lab rats’ memories.

The Science

The study was conducted at the University of California Los Angeles (UCLA) where researchers fed two groups of rats a solution containing high-fructose corn syrup — a common ingredient in processed foods — as drinking water for six weeks.

One group of rats was supplemented with brain-boosting omega-3 fatty acids in the form of flaxseed oil and docosahexaenoic acid (DHA), while the other group was not.

Before the sugar drinks began, the rats were enrolled in a five-day training session in a complicated maze. After six weeks on the sweet solution, the rats were then placed back in the maze to see how they fared.

Sugar & The Brain

A closer look at the rat brains revealed that those who were not fed DHA supplements had also developed signs of resistance to insulin, a hormone that controls blood sugar and regulates brain function.

“Because insulin can penetrate the blood-brain barrier, the hormone may signal neurons to trigger reactions that disrupt learning and cause memory loss,” Gomez-Pinilla said.

In other words, eating too much fructose could interfere with insulin’s ability to regulate how cells use and store sugar, which is necessary for processing thoughts and emotions.

Everyone is always focused on the effect of high-fructose corn syrup on weight gain and obesity, but this study shows that a high-fructose diet not only harms the body, but harms the brain as well.

What Kind of Sugar Is Most Damaging?

High-fructose corn syrup is commonly found in soda, condiments, applesauce, baby food and other processed snacks. What is worse is that the average American consumes more than 40 pounds (18 kilograms) of high-fructose corn syrup per year, according to the US Department of Agriculture.

The Standard American Diet (SAD) is saturated with sugar, high omega-6 fatty acids, excessive calories, trans fats, processed and pesticide-laden foods. People who have a simple, carbohydrate-based diet (bread, pasta, potatoes, rice, fruit juice and sugar) have a 400% increased risk of getting Alzheimer’s disease. New research has also linked a sugar-laden diet to Alzheimer’s disease, which some scientists are now calling “type 3 diabetes.”

Alzheimer’s disease, diabetes, depression, and obesity are national health epidemics that continue to grow. The answer is NOT to see them as individual, separate disorders, but rather as different outcomes of the same unhealthy lifestyle that have exactly the same cure. The best way to prevent Alzheimer’s is to eliminate all the risk factors that are associated with the disease—and the good news is that most of them are either preventable or treatable.

We Can Help

Being serious about brain health has no age limit, especially when a better brain can help improve your focus, mood, and memory. You can create a brain-healthy life by learning how to love and care for the most important part of your body- your brain. To learn how we can optimize your health, please call us today at 888-288-9834 or visit us online to schedule a visit.

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  1. Julie Nelson says:

    I have so valued Dr. Amen’s work and I have even sought help for a family member through your clinic. At the same time I have to say, after working with and for a functional medicine doctor, sugar is not the enemy. I strongly disagree with your titling Sugar as being an detriment to the brain. Working the body you reference and rightly so fructose & corn syrup an culprits to brain dysfunction. Then title it as such instead of gimmick it up with demonizing sugar. Sucrose is the answer and the brain, liver, muscle tissues, conversion to energy in the cells is optimal. Proper food combining is as essential. Those who starve themselves of proper carbs and sugars are hurting themselves just as much! Again I value your work in so many ways, but this blog is misleading the public! Thank you for giving my response your attention. – Julie Nelson

    • Sarah O says:

      I believe the Amen clinic was talking about the added sugar in those foods. I eat all those items with no added sugar. Maybe in some cases to much food that breaks down into sugar in the body could be harmful. I am Vegan so that really would take a lot of food off my plate, as I stay with plant foods only.

    • Dave says:

      Julie, if you eat vegetables they have fructose and glucose in them in case you didn’t know. Nobody is saying to stop natural sugars in fruits and veggies but if you think soda HFCS sugar and sugar added to foods are necessary then be my guest…

      Obesity in the U.S. is correlated with high carb diets and added sugar to processed foods. Veggies and fruits are ok.. but fruit juice, soda and processed foods are not ok. Too much bread and pasta are also not a good idea.

    • amanda sechrist says:

      I agree with Julie!! I think you are right that sugar is not the enemy. As a former food addict, I always thought “sugar” was what set my binge but really restricting any food set my binges. I learned to focus on health, whole foods, and really no food is the enemy.

  2. Malcolm says:

    So what was the out come of the rats return to the test maze?

    • Cindy says:

      Malcom, I am with you. My first thought was, “Huh?”. It is a glaring miss. I can only assume the sugar rats did not fare well in the maze but they needed to shorten the article. If they did do well, then this article is moot about the effects of sugar regarding cognitive skills. I do find these “rat” studies are always the extreme. Sugar vs. Omegas? Not sugar vs. no sugar? If it didn’t come out in the Omega rats favor then that is a story in itself.

      • Cheryl says:

        Right, I read the article through twice wondering if I missed how the rats fared with and without the sugar. I thought that was exciting news though, that the rats which were fed the omega/DHA were protected from developing insulin resistance! As a partially reformed chocoholic that’s good reason for me to protect myself with a supplement & regular fish/flax in the diet.

    • Jeff says:

      Ditto. Not a very comprehensive summary without citing the results of the maze experiment. “Glaring miss” or intended omission due to inconclusive results? I’m sure the article still has merit but the poor summary kind of compromises the message. I’m not a troll – I promise. I never comment on these things but this was just too much.

  3. Dan Stanley says:

    I wanted to thank you for all the work you are doing to help us have a healthy brain.

    I have been quoting you in a post-graduate program dealing with the relationship between healthy physical life design and spiritual life design activities.

    Dan Stanley, PhD

  4. Sheryl Hamilton, PhD says:

    At the 2015 AACC World Conference, my friend Sheila Wright and I signed up for the brain health coaching course. We were told that a scan would come with it. Although I have not yet finished the course, I would like to go ahead and schedule my SPECT scan. Since June 2 at the age of 66, I have had a heart attack, a virus that attacked my middle ear resulting in hearing loss and imbalance. I am 5 feet 1 inch, weigh 99 lbs, don’t smoke, never did, no diabetes, & no family history of heart problems. Oh, and I had Graves Disease at the age of 25. I need to find out how to over come all this damage to my body. Thank you.

  5. Ramona Etheredge says:

    When you test patients do you make us run thru a maze for six weeks?
    I hate that HFCS has been put into everything including my husbands beer, he can barely find his way back home.; and why aren’t beer companies required to print out the ingredients of beer?

  6. Pamela Taylor says:

    So after eating a high sugar meal I feel as if I have dropped several IQ points. I feel sluggish in mind as well as body. I definitely do not have the clarity I need to function at a high level. Vilanizing sugar is like vilanizing crack cocaine. It’s long overdue. Thanks for always speaking the truth.

  7. George says:

    I cannot tell you how much better I feel after giving up soda, ice cream and other sugar related foods. I have an appointment next month at one of the Amen Clinics. Can hardly wait.


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