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Diet Soda Tied to Memory Loss

You can cut your chance of stroke and dementia by avoiding diet soda.

Your daily diet soda may seem harmless—after all, you tell yourself, it doesn't have calories.

Wrong. According to a study of about 4,300 volunteers, aged 45 and up, diet soda may triple your chance of stroke or dementia within the decade. When the same researchers looked at brain scans and results of cognitive tests, they found that people who drank diet soda every day tended to have smaller brains and poorer memory, two risk factors for dementia.

Sugary soda and fruit juice aren’t safe, either, they concluded. In fact, two sweet beverages a day was associated with more long-term memory loss.

Another group, at the University of Miami, also concluded that a daily diet soda could increase your risk of stroke. And in that research, it was linked to heart attacks as well.

That’s a big price to pay for fizzy sweetness.

The Miami researchers found that you could safely drink diet soda—just not every day. However, you may not want to take the risk, since researchers are still guessing at the answers to the question of why diet soda is bad for you. It is tied to obesity and diabetes, in part because it may cause poor circulation. Those circulation issues may be the underlying reason it could add to your risk of stroke, dementia, and long-term memory loss. You need a constant supply of blood to the brain. High sugar intake is also tied to poor circulation that could hurt your brain.

What about those healthy-sounding fruit smoothies? Whole fruits and vegetables are a better choice. Juices are a fast, fiber-less, shot of sugar, which also could aggravate long term memory loss, as well as weight gain. You can make your smoothie healthier by including vegetables and almond or soy milk.

Energy drinks aren’t healthy either—they’re often packed with sugar and the stimulants may be dangerous. Consuming just 16 ounces of an energy drink elevates blood pressure and stress hormones in young, healthy adults, according to a 2015 study by the American Heart Association. Sport drinks, which contain minerals and electrolytes to replace water and electrolytes lost through sweating during exercise, are a better bet, but probably unnecessary, and should be sugar-free.

There’s really no good reason to use the most popular artificial sweeteners, because they also don’t reliably help you lose weight. In mice studies, at least, they appear to promote weight gain. In one study, 10-week-old mice ate a daily dose of aspartame, sucralose, or saccharin. After only 11 weeks, the mice on the artificial sweeteners were showing signs of high blood sugar, a precursor to diabetes​ that is associated with weight gain. ​

Perhaps you’ve been drinking lots of diet soda for years. You don’t need to panic every time you forget where you put your keys. But it's a good idea to learn to love water or unsweetened ice tea and coffee.