Can an extra 4 000 steps per day really lower your odds of heart disease?

• Walking has tremendous health benefits
• An extra 4 000 steps per day can lower your risk of heart disease
• This is according to a new study, which found that 8 000 steps are even better

Walking is arguably one of the most underrated forms of exercise. Apart from weight loss, among the biggest, proven benefits of regular walking is that it increases muscle strength; reduces the risk of developing breast cancer; boosts your immune system; improves your mood and reduces the risk of depression and anxiety; and can reduce your risk of heart disease by up to 30%, notes Harvard Health.

If you found the last point particularly eye-catching, but you haven't yet incorporated a daily walk into your everyday routine, that’s okay, because simply taking an extra 4 000 steps per day (a number considered low for adults) may help, even if you walk at a leisurely pace.

This is according to a new study of 4 840 Americans ages 40 and older (previous studies on step counts and mortality have been done, but primarily involved older adults or people with debilitating chronic conditions).

The study was done by a research team from NIH’s National Cancer Institute (NCI); National Institute on Aging (NIA); and the Centers for Disease Control and Prevention (CDC), who looked at the association between step count, intensity, and risk of death. Their findings were published in JAMA (Journal of the American Medical Association).

However, doubling or tripling that step count has even greater benefits in terms of lower mortality risk from all causes, the study found.

Number of steps vs. step intensity

Participants were asked to wear a device on their hips, called an accelerometer, that recorded the number of steps they took every day. The more steps they took, the more it was found to lower their risk of dying over the following 10 years, irrespective of age, sex, or race. This was done between 2003 and 2006, and participants were then followed for mortality through 2015 via the National Death Index.

In those who walked 8 000 steps per day, when compared to participants who walked only 4 000 steps per day, it was revealed that they were about half as likely to die for any reason, but particularly from heart disease:

• Taking 8 000 steps per day was associated with a 51% lower risk for all-cause mortality (or death from all causes).
• Taking 12 000 steps per day was associated with a 65% lower risk compared with taking 4 000 steps.

The team also found that the number of steps per day is more important than step intensity (number of steps per minute), as they reported no association between step intensity and risk of death, after accounting for the total number of steps taken per day, although they encouraged future studies of walking intensity and mortality, as very few have been done.

‘The main thing is to get moving’

"At NIA, we've long studied how exercise is important for older adults, and it's good to see further evidence from a large study with a broad sample that the main thing is to get moving for better overall health as we age," said Dr Eric Shiroma, co-author of the study and NIA Intramural Research Program scientist.

In an updated article by Harvard’s Health, Dr Edward Phillips, assistant professor of physical medicine and rehabilitation at Harvard Medical School also said: "This study supports what we know about the marked benefit of achieving about 8 000 steps per day."

Philips explained that most people typically get around 3 000 to 4 000 steps per day without doing any intentional exercise, which includes things such as doing household chores, checking your mailbox, or going grocery shopping, for instance.

"But if you regularly walk another 4 000 steps a day to reach a total of about 8 000 steps per day, there's a dramatic difference in whether you live or die over the next decade," he added.

Although the study's observational findings can't technically prove that walking helped forestall death, the researchers controlled for a number of factors, including the diverse study population and long follow-ups. Another strength of the study is that participants used accelerometers, as opposed to self-reported activity, making the results much more reliable.

Bottom line: Based on these findings, the argument that you need to clock in a minimum of 10 000 steps per day for good health is a myth.