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The #1 Eating Habit to Avoid to Keep Your Brain Sharp, Says Dietitian

You may want to limit your intake of this ingredient.

There are so many lifestyle factors that play roles in your brain health. Socializing, sleep, physical exercise, and nutrition are just some of the pillars that can keep you sharp. When it comes to nutrition, there are certain foods we know can aid in brain health, like those high in omega-3, fruit, vegetables, and items rich in antioxidants.

While these are the foods you should be enjoying frequently, there is one eating habit you should avoid to keep your brain sharp… consuming high amounts of refined sugar. Read on to learn more about how processed sugar can negatively impact your brain.

It is important to first differentiate between the sugar naturally found in foods like milk and fruit from the processed sugar often added to food and drinks. When talking about refined sugar, think about what you use in baking, what might add to your coffee, the type of sugar in soda and juice, and the form found in an array of candy, pastries, and even savory sauces.

The American Heart Association estimates that adults consume about 77 grams of sugar per day, about three times the recommended intake for women. For reference, the AHA recommends women consume fewer than 25 grams daily, while men should have no more than 36 grams.

sugary junk food

A diet high in refined sugar is thought to increase risk of developing type 2 diabetes, and research suggests a type 2 diabetes diagnosis increases one's risk of developing Alzheimer's disease. Another study documented a correlation between blood glucose levels and dementia, where higher glucose levels in individuals with and without diabetes were related to increased risk of dementia.

While there are genetic factors that likely play a role in brain health and risk of memory-related disease, current research indicates that your food and drink choices have an impact, too. In fact, another study completed in rats found that a high-sugar diet, especially in the form of high-fructose corn syrup, can increase brain inflammation and lead to impaired memory.

A modest amount of sugar likely will not impact your health negatively, and if you find yourself consuming multiple sources of sugar daily, try cutting back to meet the AHA's recommendations for sugar intake. Swap regular soda for diet or unsweetened sparkling water, use a zero-calorie sugar substitute in place of sugar, swap candy for fruit, and load up on protein and fiber-dense foods to keep you full and satisfied, and less likely to overeat sugary items.

Many of the current studies analyzing the impact of sugar on the brain have been conducted on animals. While this is helpful is providing us preliminary information and serves as a template for how to conduct similar studies in humans, more research is needed to build conclusive guidelines around sugar intake for brain health.

However, what we currently know points to limiting your intake of refined sugar to reduce your risk of many diseases, like type 2 diabetes, Alzheimer's, dementia, and even obesity and heart disease.

Melissa Rifkin, MS, RDN, CDN
Melissa is a Connecticut-based registered dietitian with over 15 years of experience, including clinical and outpatient settings, and runs the popular nutrition education Instagram account, Confessionofadietitian. Read more about Melissa