If you type the phrase “10,000 steps” into the Amazon.com search bar, about a half dozen book titles will come up with promises to help you take 10,000 steps daily so you can “walk your way to better heath,” “lose weight…at any age,” and achieve “lifelong fitness,” among other happy outcomes. Where is the science that turned the number 10,000 into health magic?

Nowhere, actually. The idea that taking 10,000 steps daily can make you live healthier and longer originated in a Japanese marketing campaign in the mid-1960s. That’s when a company began selling a Fitbit prototype called the manpo-kei—Japanese for “10,000-step meter.” Since then, 10,000 has been a number in search of a study result to back it up.

Don’t get me wrong. Walking is great exercise, and really good for you. Study after study has demonstrated that. But none of them has nailed an optimal number of steps to take. Rather, taken together, they pretty much show that up to a point, more is better than less.

For instance, one research trial involving almost 17,000 women with an average age of 72 found that those who took at least 4,400 steps per day were more than 40 percent less likely to have died of any cause four years later than women who took only 2,700 steps daily. (They were all tracked with gadgets that measured their steps.) Women who took 5,900 steps a day were even less likely to die during the follow-up period, but the difference wasn’t as dramatic. The positive effect continued up until about 7,500 steps daily. Then it leveled off. Ten thousand steps a day didn’t protect from death any better than 7,500 steps.

Another study, this one involving more than 2,000 adults ages 38 through 50, found that those who took at least 7,000 steps a day had a lower body mass index (BMI), a lower incidence of high blood pressure, and a lower incidence of diabetes than those who took fewer steps. Not surprisingly, after 11 years of follow-up, they were also less likely to have died than those who took fewer than 7,000 steps each day. But here’s the thing: Walking more than 10,000 steps on a daily basis didn’t confer extra benefit. Other studies also didn’t reach the conclusion that 10,000 is the be-all and end-all.

None of this is to say that taking 10,000 steps daily is a bad idea. And if the number 10,000 motivates you to incorporate more physical activity into your life, then it’s a great idea! Just know that science doesn’t compel you to reach that number.

Moreover, there are ways to exercise other than walking if walking doesn’t appeal to you—or doesn’t appeal to you on a daily basis. My wife and I like to go for walks, but on days we don’t, I work out on a stationary bike. I enjoy mixing it up. Some people like to row, for instance. Others enjoy working in the garden—pulling weeds, carrying away brush, and digging to plant new bulbs are perfectly legitimate forms of physical activity.

Because there are so many ways to work exercise into the day, I like the way the CDC puts its recommendation. It talks about the amount of time one should spend exercising. Specifically, it says that all adults (ages 18 and up) should engage in at least 150 minutes of moderate-intensity activity per week—which could be done, say, 30 minutes five days a week. Brisk walking is given as an example, not a directive. As long as the exercise requires the exertion that brisk walking does, it’s fine. (It’s also fine that “brisk” is a moving target, meaning something different for an 18-year-old than for an 80-year-old.)

I should mention that the CDC also recommends doing strength-training exercises two days a week to keep your muscles strong and, for people 65 and older, activities to improve balance, like standing on one foot. (Of course, balance exercises are good for people of all ages, not just those who are older.)

Not there yet? Don’t beat yourself up. Take it in steps, whether literally or metaphorically.