When Six-Pack Abs Are Bad for Your Health

Credit: Tim McGuire / Getty Images

Blame it on Ronaldo. Pro athletes and fitness geeks everywhere are obsessed with six-pack abs. What better way to show the world how athletic you really are, right? Not exactly. “Six-pack abs are kind of a status symbol in the fitness industry, and I thought, in order to be legit, I would need the six-pack,” says Noelle Tarr, a personal trainer and former triathlete. The problem, as Tarr found throughout her athletic career, is that you can very easily sacrifice your performance, and well-being, for it.

The main problem is that a six-pack isn’t primarily gained through crunches or sit-ups or athletic prowess. “The vast majority of your ‘six-pack abs’ is simply due to nutrition,” says Sam Leahey, director of sports science at Precision Sport Science. “It’s not as much a function of training.” In fact, he estimates that six-packs abs are probably about 90 percent the result of eating less.

Generally, experts say that a man has to get down to about 10 percent body fat in order for his abs to show. For women, the number is closer to 15 percent fat. And that’s not even for fitness-model-level definition. According to a 2009 guideline from the American Council on Exercise (ACE), about 2 to 5 percent fat in men and 10 to 13 percent of fat in women is essential. That is tough on the body. Essential fat is the fat that is incorporated into bodily tissues, like bone marrow, the spinal cord, and various organs. The ACE categorizes an athletic body fat percentage as 6 to 13 percent for men and 14 to 20 percent for women; others argue that these numbers could be a bit lower for young adults and a bit higher for older adults.

Having a lower than average level of body fat isn’t necessarily harmful but dropping below the fat percentage that is right for your body can mess you up. Tarr, for example, lost so much weight in her pursuit of a six-pack that she stopped getting her period and began suffering from significant anxiety. “I think that my pursuit [of] only the physical and what I looked like was clouding my ability to listen to my body and rest and recover and take care of myself,” says Tarr. At her lowest point, she sustained a severe injury from too much running but was still longing to push herself to get going again so she wouldn’t lose progress toward her flat-ab goal. “In essence, that’s the problem with the six-pack ab mentality. They see it as a destination.” 

So, six-packs don’t automatically make you fit, but they also don’t mean you’re underweight or addicted to exercise. Really, those abs aren’t great correlations for much of anything. “These are not markers of health and wellness,” says Leahey. “Mortality issues aren’t correlated with how many abs you can see in the mirror or the level of skin fold at the abs.” There are quite a few other ways to more objectively measure physical fitness, including looking at relative strength, aerobic fitness, body fat percentages, or relative race times.

“A lot of people who do sports are dedicating a lot of time to that, and that brings them joy,” says Tarr. “There’s nothing wrong with pursuing six-pack abs — if that makes you happy.”