What the science says, and what to do next
By Austin Perlmutter, MD
Excess added sugar consumption is linked to brain diseases, especially when in liquid form (sugary beverages)
Even "natural" sweeteners like honey and maple syrup should be consumed in moderation
Overall, decreasing intake of added sweeteners of any kind may be the best plan for health
Stevia, monkfruit and allulose may be among the best sugar alternative options based on current risk/benefit analysis, but there's still more to learn
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? Read on!
Your brain is only about 2% of your body’s weight. Yet it uses up around 20% 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 for developing Alzheimer’s disease.
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 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, since both honey and maple syrup have a slightly lower effect on blood sugar than table sugar, and each contain 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 towards 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 monkfruit. 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.
What should you actually eat?
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 monkfruit, stevia and allulose may be the most promising as it relates to overall risk/benefit profile, but again, there’s lots more to learn.