Sugar is the everyday toxin. While we are constantly bombarded with messaging that sugar is bad for us, the reality is more severe. The truth is that sugar is likely the number one toxin human beings we consume.

Sugar is a carbohydrate that the body uses as fuel to make energy in our cells. All carbohydrate-containing foods are composed of some form of sugar, and many different types of sugars exist. These include glucose, maltose, lactose, fructose, and dextrose. Ultimately, the body converts all forms of carbohydrates into glucose, which is the primary fuel source for our cells. And the body will not differentiate if you are consuming “good” sugars (like fruits, vegetables, and grains), or “bad” sugars (like processed foods, sodas, candy, crackers, and baked goods). Ultimately, your body converts any form of sugar you consume into glucose.  

What’s the Big Deal About Sugar

Humans have thrived on sugar for centuries, and to an extent, sugar is essential for energy production in our cells, especially brain cells. Without a constant supply of glucose to the brain, one may not survive. So what is the big deal about sugar? We are consuming way too much of it. In fact, the average American eats 152 pounds of sugar annually. This is a stark rise from 1882 when we were eating just 6 pounds per capita. Just in the past 50 years alone, sugar consumption has tripled.

The reasons for our obsession with sugar are not surprising, given the highly addictive nature of sugar. The sweetness of sugar stimulates the reward pathways in the brain and has you coming back for more and more. In fact, research done by Serge H. Ahmed shows that the sweet taste is 8 times as addictive as cocaine. Rats offered IV cocaine versus sweetened water always chose the sugar. Furthermore, even previously cocaine-addicted rats switched to the sweetened water. If that’s not enough to confuse your sweet tooth, in a 2012 publication in Nature, “The Toxic Truth About Sugar”, Robert H. Lustig argues that sugar should be a controlled substance like alcohol and tobacco. 

The Long-Term Effects of Too Much Sugar

We have known for years that diets higher in sugar and carbohydrates increase one’s risk for metabolic disorders, like diabetes and metabolic syndrome. However, a wealth of research is now linking blood glucose levels with risks for brain-related disorders, including dementia. Research shows that type 2 diabetes doubles your risk of developing Alzheimer’s disease. The main focus of this research relates to the effects of higher carbohydrate consumption and particular areas of the brain involved in learning and memory, like the hippocampus and amygdala. Even higher normal fasting blood glucose (not even in the diabetic range), seems to be associated with atrophy of the hippocampus and amygdala.    

And it is not just glucose that is the culprit. Insulin, your fat-storage hormone involved in the transfer of glucose into the cells, plays a significant role as well. Particularly, deregulated brain signaling of insulin seems to be a key player in the pathogenesis of Alzheimer’s Disease. This deregulated signaling of insulin in the brain occurs once insulin resistance sets in. The higher carbohydrate and sugar consumption, the higher the risk for insulin resistance. Insulin resistance and ultimately diabetes are among the known risk factors for Alzheimer’s disease. Research also reveals how higher sugar diets change gene expression in the brain in ways that promote more cognitive decline. In particular, the expression of one of the most important growth factors involved in neuroplasticity, brain-derived neurotrophic factor (BDNF), seems to be reduced in the setting of higher sugar diets.

So, a combination of higher glucose concentrations, impaired insulin signaling in the brain, coupled with impaired gene expression of vital growth factors creates the perfect storm for brain atrophy and ultimately cognitive decline and frank dementia.

Practical Steps to Reduce Sugar

However, all is not lost! Now is the perfect time to make some easy, healthy swaps in your diet. First and foremost, get more knowledgeable about where sugar is hiding. Believe it or not, sugar masquerades in dozens of hidden places, from condiments, salad dressings, alcoholic beverages, and of course: carbohydrate-filled pasta, bread, crackers, and more. Eliminating processed foods will significantly reduce your consumption of hidden sugars. Your goal should be to eat a mostly plant-based diet, high in vegetables and fruits with some grains, fish, and organic, pasture-raised meats as condiments. Sticking to the 75/25 rule helps keep perspective on this. Fill 75% of your plate with colorful vegetables, while loading the remaining 25% with meat, fish, and grains. Also don’t forget to incorporate healthy fats throughout the day.  

Choosing the Right Carbs

Complex sugars that occur naturally in starchy vegetables, fruits, and whole grains are a wiser choice than simple sugars. Complex carbohydrates are higher in fiber, making them more slowly digested, with a slower and steadier release of insulin. Fiber is a superstar in and of itself too since it is beneficial for the microbiome or gut ecology. And a better microbiome equates to a better metabolism, less inflammation, and a better gut-brain connection. Lastly, complex carbohydrates are coupled with anti-oxidant and anti-inflammatory bioflavonoids and phytochemicals which synergistically help to optimize health and fight disease. 

But before you simply switch to artificial sweeteners — beware! As already reviewed, artificial sweeteners are highly addictive. On top of that, research suggests that even sugar alternatives increase your risk of obesity, diabetes, metabolic syndrome, and cardiovascular disease. And if that’s not enough, since these sugar alternatives are infinitely sweeter than actual sugar, they end up confusing your metabolism by revving up insulin production and release. Sound advice would be to avoid most artificial sweeteners. The one exception may be stevia which comes from the leaves of the stevia plant. However, you should use it sparingly. A little in your morning tea or coffee should be fine, but make sure to choose a product that is 100% stevia without any additives.  

So, while a treat here and there isn’t a disaster, to optimize your cognitive health for years to come, aim for a diet low in sugar and carbohydrates. However, think of sugar as a recreational drug. If you find it difficult to break habits, be judicious about your choices.   

I promise, there are plenty of healthy and delicious alternatives. Even better, your body and brain will thank you!

Learn More

Dr. Rana Mafee is dual board certified in Neurology and Integrative Medicine. She is passionate about using functional and integrative philosophies to prevent & reverse a host of chronic conditions. Dr. Mafee is particularly focused on helping patients work through neurodegenerative disorders. Head over to her website to learn more.

You can also catch her episode on the Lindsey Elmore Show, Understanding Cognitive Decline, here.