In this era of “all or nothing” thinking, more and more scientific studies are proving the value of moderation. The caveat, though, is that each person is unique, and doing what’s best for your health and happiness is the most important thing for you.

Case in point, most educated people will agree that smoking is bad for you. Caffeine has its benefits. Not all fats are “bad.” Some people perform well as vegans, while others function at their best with more meat in their diet. Running is good for you. Yes, but when it comes to taxing your body with long, challenging runs year after year, well … the effects of that aren’t as clear.

Of course, exercise and running are good for you and definitely better than sitting on the couch. But the intensity and duration of those workouts is causing some interesting study results. In fact, a recent study by the University of Illinois at Chicago and Kaiser Permanente discovered that Caucasian males who exercise at high levels are 86 percent more likely to have a buildup of arterial plaque by the time they reach middle age, than people who exercised at lower levels. The study monitored 3,175 participants from 1985 through 2011. Participants were between the ages of 18 and 30 when the 25-year study began.

Participants in the study were divided into three groups: those who exercised less than the nationally recommended guidelines of 150 minutes a week, those who met the national guidelines of 150 minutes a week and those who exercised more than 450 minutes per week. The third group of exercisers had results the researchers didn’t anticipate—a higher incidence of plaque buildup for white men. African American males showed no increase in plaque buildup with higher levels of exercise. Females showed a slight increase. The study did not investigate whether the build-up led to a higher incidence of heart disease, although the initial conclusion is the plaque is more stable than the kind that contributes to heart attacks and strokes. The researchers are now looking at outcomes based upon the data. Stay tuned.

Another study from the Department of Family Medicine and Community Health at the University of Minnesota in Minneapolis also looked at heart plaque buildup, this time in marathoners. For the men’s study, everyone had run at least one marathon a year for 25 years. Some men had varying degrees of plaque buildup, while others had none. For the study of female marathoners, all participants had run at least one marathon a year for 10 to 25 consecutive years. The researchers found minor plaque buildup across the group. Running didn’t seem to have caused any heart damage in either group.

A third recent study, from the Department for Diagnostic and Interventional Radiology and Nuclear Medicine at University Medical Center Hamburg-Eppendorf in Hamburg, Germany, examined the heart health of triathletes. Both men and women were included in the study, with showed 18 percent of the male participants had increased myocardial fibrosis (or scarring) in their heart. Similar scarring was not evident in the female test subjects.

Confusing, right? The bottom line is that being physically active is still considered good for your health, but it isn’t enough to make up for poor choices. Not smoking, eating a balanced diet, stress management, medical history and genetics all play into whether or not you’ll develop heart disease. Besides exercise and good living, be sure to visit your doctor for regular checkups. Even if the health care trend is treating illnesses instead of preventing them, you can do your part to stay fit, healthy and ahead of the heart disease curve.