Science
It's also one of the most common alternatives to sugar, found in over 6,000 products and sold as NutraSweet® and Equal®.
The same amount of aspartame and sugar has the same number of calories as sugar, but since aspartame is 200 times sweeter than sugar it goes a lot farther.
Because of this, aspartame often used in diet sodas to cut down on calories. But in April 2015 PepsiCo announced that it will no longer use aspartame in Diet Pepsi, amid popular concern that aspartame causes cancer and other health problems.
Do these claims actually hold water? In its Reactions video series, the American Chemical Society put the rumors to scientific scrutiny.
The concern about aspartame causing cancer comes from the fact that your body breaks it down into formaldehyde, which is a substance known to cause cancer under long term exposure.
It's worth noting that there's an inconsistency here: 12 oz. of fruit juice can put up to 5 times more formaldehyde into your body than the same amount of diet soda, yet no one is concerned about fruit juice causing cancer.
And there's no reason to be concerned about the formaldehyde from fruit juice, either. Formaldehyde is used pretty much immediately in the body to make amino acids, the components that make up proteins - it doesn't get stored and build up to potentially harmful levels. What's not used to in the process of making proteins is turned into formic acid, which is then excreted in urine or broken down by carbon dioxide and water.
Flickr / Rusty Clark - Back In One Piece
Just don't do this.
One study compared vital signs, lab tests, and symptoms of a group of people who took pills with the amount of aspartame in 10 liters of diet soda per day for 24 weeks with a group that took a placebo pill. The scientists found no differences between the two groups, even at that extremely high daily dose of aspartame.
No link has been found between aspartame and cancer, and people have been looking: aspartame is one of the most heavily researched food additives of all time since the FDA approved it for human consumption in the early 80s.
Besides the concerns about cancer, some people have claimed reactions to aspartame including headaches, seizures, nausea, anxiety, and depression. To test this, scientists ran a study in which people who claimed to have reactions to aspartame were given snack bars with the sweetener or control snack bars that didn't contain aspartame. Again, there was no difference between the two groups, and zero evidence of an acute response to aspartame.
Aspartame is only really a concern for people with phenylketonuria, a condition with makes them unable to break down phenylalanine, another byproduct of aspartame in the body. If phenylalanine accumulates in the body, it can cause brain damage. But anyone who metabolizes phenylalanine normally doesn't need to worry.
Despite the hype they get, claims about dangers of aspartame are from "anecdotal evidence or flawed studies," the video says. So enjoy that diet soda, in moderation.