If you’ve played the free version of any mobile games, you’ve probably seen more than your fair share of advertisements for other games while playing. After all, running ads for other applications is the primary source of income for most apps that have a non-paid version.

You may have noticed a number of ads for “brain games,” along with some pretty wild claims about their effect on cognitive function. Some advertisements will display “Your brain age is…” and a number that starts at 100 but begins to decline as the video of gameplay continues. The implication is that this game will either assess your cognitive state, or even reverse your brain’s aging process. Other ads charge out of the gate with “This game cures Alzheimer’s!”

First, that claim about curing Alzheimer’s is utterly false. There is no cure for this disease, and there are certainly no computer games that will diagnose, prevent, or reverse it. These advertisers are preying on anxiety about getting older. And it works. Dementia is frightening.

The truth is that there is no proof that these games provide anything but a diversion. Published science (the kind where actual science people do experiments using the Scientific Method, and then more science people say “hey wait, let’s do that again to make sure”) has found no real cognitive benefit to these so-called “brain games.” Nobody went in aged 85 and came out with the brain function of a 30 year-old, no matter what the advertisements might indicate.

But…the people who play the game got better at it; that means they’re reversing cognitive decline, right? Not that any experts can detect outside of playing the game itself. In other words, when you play a game over and over, you tend to get better at it because you learn what to do.

But…isn’t stimulation good for your brain as you age? Of course it is. But there are vastly more and better ways to get that stimulation and keep your brain as healthy as possible for as long as possible, other than matching shapes on a smartphone. Reading books, talking to other people, going for walks or other physical activity, eating right—all of these are far superior to playing a mobile game. Perhaps playing a mobile game is preferable to sitting and doing nothing, or staring at a TV, but probably not by much.

One of the common tactics used by con artists is to prey on fear or anxiety. Notice when an advertisement for a new mobile app is using this same method, and ignore ads that use unproven medical claims. A game that was proven to improve brain function and slow or reverse dementia would be considered a medical device and have to be approved by the FDA. And let’s face it—it would likely cost a lot more than $1.99.

Besides, almost every mobile game you see advertised in this way ends up just being a knockoff of a certain other confection-based game you probably already have installed.