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What Sugar Can Do to Your Brain

Excess consumption is linked to conditions like Alzheimer's.

Key points

  • Excess added sugar consumption is linked to brain diseases.
  • Even "natural" sweeteners should be consumed in moderation.
  • Overall, decreasing your intake of added sweeteners of any kind may be the best plan for health.
Source: Suzy Hazelwood/Pexels + Holdendrils/Pixabay
Source: Suzy Hazelwood/Pexels + Holdendrils/Pixabay

You’ve likely heard some version of the story: Don’t eat sugar; it’s bad for your health. Indeed, research shows that consuming too much of the sweet stuff (especially when added) is linked to all sorts of issues with our brains and bodies. But “sugar” can come in a number of forms with different potential impacts on health. So, what does the research really say about the link between sugar and your brain health?

Your brain is only about 2 percent of your body’s weight. Yet it uses up around 20 percent of your total energy. Most of this energy comes in the form of glucose. You’d think, then, that more sugar is better as it relates to brain health. Yet, consuming more added sugar (especially in beverages) is linked to worse brain health including an increased risk of developing Alzheimer’s disease.

Added Sugars ss. Sugars Found Naturally in Foods

One of the most important points, as it relates to research connecting health and sugar intake, is the difference between added sugars and sugars found naturally in foods. For example, there are significant differences in what happens if you eat a blueberry or drink a blueberry-flavored sugary soda. The blueberry has more fiber, antioxidants, and natural vitamins and minerals. This helps explain why the most convincing associations between brain conditions like depression and dementia and sugar are when we drink it in the form of sugary beverages (think soda, coffee drinks, energy drinks, etc.).

Of course, there are a number of different forms that added sugar can take. There’s honey, maple syrup, coconut sugar, agave nectar, cane sugar, evaporated cane juice, and so on. You’ve likely heard people extol the virtues of “natural sugar” like coconut sugar and honey over the dangers of table sugar. There is some truth to this; both honey and maple syrup have a slightly lower effect on blood sugar than table sugar, and each contains vitamins, minerals, and antioxidants that are missing in standard sugar. Yet this doesn’t negate the fact that all types of “natural” sugars tend to significantly impact blood sugar, which, when done repeatedly, is thought to be an issue as it relates to risk for a number of diseases including brain problems.

To avoid spikes in blood sugar and other issues with metabolism, many have instead turned toward artificial and “natural” sugar alternatives. This list includes artificially synthesized molecules like aspartame and sucralose as well as sugar alcohols (erythritol, xylitol) and plant-derived sweeteners like stevia and monk fruit. It’s important to note that we don’t know that much yet about the long-term health impact of any of these alternatives, though some research has suggested that the artificial sweeteners in particular may be worth avoiding.

As it relates to the more “natural” sweeteners, some recent work has questioned whether erythritol in particular might be linked to negative health effects on our brains and bodies. Yet conflicting research suggests that, mechanistically, this molecule could have healthful effects on our metabolism. Other work highlights potential health benefits associated with sweeteners like stevia and allulose. We’re also learning that one of the major links between these types of molecules and our brain health may be by way of these sweeteners’ effects on our microbiome.

Research-Supported Recommendations

All of this can seem incredibly complicated. Are there any good options when it comes to getting our sweet fix while supporting our health? To this end, the research would suggest the following may be good general guidelines.

  1. In general, we will all benefit from an overall reduction in added sugars and training our brains to be more sensitive to sugar by reducing overall intake.
  2. In general, eating sugar in the form of whole foods is a better option than any processed food containing sugar, as the fiber and other nutrients can help offset the sugar’s effects on your biology.
  3. When it comes to natural sugars, there is a bit of data to suggest that certain forms (e.g., honey) may have a slight edge over table sugar, but, as per point 1, any form of added sugar should be consumed in moderation.
  4. When it comes to sugar alternatives, we are still learning about potential health effects (both good and bad) that may stem from their consumption, but these effects may work by way of the microbiome.
  5. Among sugar alternatives, some data suggest that monk fruit, stevia, and allulose may be the most promising as it relates to the overall risk-benefit profile, but, again, there’s lots more to learn.

Facebook/LinkedIn image: Theera Disayarat/Shutterstock

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