When I visit my neurologist’s office, the assistant walks behind me and tells me to turn right up ahead and then go the second room on the left, the one numbered 7. Sometimes she’ll have me get on the weight scale and tell me to read the numbers. Because most assistants in other doctors’ offices lead the way, I’ve concluded that my neurologist is measuring my cognitive abilities. So far, I’ve passed, but it feels like, at my age, I’m being constantly evaluated. One day I’ll turn right instead of left, and it’ll be all over.

When I fumble at the grocery stand, I get looks from the checkers, like: ah, another old person who doesn’t know how to use her credit card in our new machine. Or when I can’t instantly remember my phone number, I get a condescending but patient response: She must be losing it.  Or has she already lost it?

Maybe it’s paranoia. When you think you’re being observed, or you have a fear of Alzheimer’s, any mistake can lead you to the conclusion that you’re going down the dementia path. If I were 20 and misplaced my keys, I would laugh it off. But now, I second guess myself constantly— like when I can’t remember the name of someone. It’s a common complaint as we age, but it’s easy to attribute it to something serious.

Both my parents had dementia, and one of my family members was just diagnosed with early Alzheimer’s. Will I be next? In surveys, Americans fear dementia more than any other health scare: cancer, diabetes, heart attacks. Unlike cancer, there is no remedy for dementia, only medications that might slow its progression.

Maybe I fear dementia because I’ve seen it up close with my parents. I clearly remember the time I handed my mom her toothbrush, and she asked what she was supposed to do with it. Her dentist had told us her teeth were in bad shape, and we needed to make sure she was brushing. But obviously she had forgotten how to do it or even what a toothbrush was for.

Or the time we were getting ready for a potluck dinner at my niece’s. When I was growing up, my mom cooked extravagant meals for a family of nine. But now, in her mid-80s, she didn’t know how to cook green beans.

To avoid or slow the progression of dementia, doctors advise getting more exercise, abstaining from alcohol, eating the right foods and getting enough sleep. I’ve done all of that. But I’ve come to realize that the best thing is to stop worrying and anticipating something that may never happen. We all need to prepare ourselves for old age: making sure our will is up to date and that plans and wishes for the last stages of life are recorded and made known to our loved ones.

But beyond that, we need to enjoy life, especially as our days are numbered. Worrying is not useful and distracts us from enjoying the company of friends, from noticing the sunset, from hearing bird songs. That’s what brings us pleasure, and research shows that being happy also helps avoid dementia.

Enjoy this day, I tell myself. None of us knows how many we’ll have.