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It’s not so much the six pack itself, but the manner in which it is obtained that can indicate whether or not the person is healthy.
Just a few centuries ago, wealthy aristocrats would have chuckled wryly over the rims of their fancy goblets at the thought of six-pack abs, which were considered a mark of the peasantry.
Poor people didn’t have fast food in the 16th century, and they worked the land all day, every day, often resulting in a lean and chiseled physique.
Five hundred years later, the script is flipped, kind of—rich and poor alike are decades deep into a love affair with the six pack.
But is this change of heart really a healthy one?
In short, sometimes yes, but oftentimes no.
Getting to a clear answer starts with a skin-deep understanding of the roles of fat in the body.
A Closer Look at Fat
Healthy omega fatty acids are instrumental in cell growth, energy storage, tissue protection, hormonal regulation, and more.
It is because of fat that humans can absorb vitamins A, D, E, and K.
In some cases, fats help proteins execute their functions, and in others, they can counteract proteins that get converted into pro-inflammatory substances.
They may have been exiled to the attic of the well-intended, yet slightly misguided food pyramids of the 90s, but make no mistake: fats are an essential macronutrient, just like protein and carbohydrates.
Dip too low below a certain threshold, and you could lose much more than your love handles.
Minimum Viable Body Fat Percentages by Gender
Universal standards for minimum viable body fat have yet to be established, and considering the many circumstances that can affect these numbers (environment, genetics, chronic conditions, body type, etc.) they may never be.
Still, most experts are at least comfortable throwing out a minimum body fat range for men and women.
Here’s what we landed on as an average of the dozen or so sources we consulted on the matter:
- Men: 7-15 percent
- Women: 14-25 percent
Fat is an essential part of the fetal development process, which is why women need more of it.
Aside from this purpose, both men and women need a minimum reserve of fat to be used in tissues like bone marrow, viscera (abdominal organs/tissues), and even the brain.
Taking only this immediately required fat into account, men could technically get to around two percent, and women could dip below ten percent, but not sustainably and not without consequences.
In order to have a six pack, men have to drop down to about five or six percent body fat, and women would need to be around eleven or twelve percent.
So, is it really that bad to just be two or three percent below the recommended minimum?
What about a really fit athlete who eats 2,000+ calories and works out a lot?
The jury may be split, but it’s not looking so good for the six pack.
When Six-Pack Abs Are Bad
It may be convenient for the sake of researching and writing to treat all six packs the same, but there’s a big difference between extremely sculpted abs and “Hey, I can see a couple lines!”
That difference may even cross the minimum body fat threshold, especially if a person is genetically predisposed to distribute less fat to the lower abdomen (meaning they could have visible abs at a slightly higher body fat percentage than normal).
Most of the research findings below expressing the pitfalls of low body fat reference more extreme cases (i.e., the very shredded six-pack).
Underweight Status Is Connected to Increased Mortality
In a large review from the University of Zurich covering 31,578 participants from studies spanning a period of 16 years, the 3% of participants who were underweight demonstrated increased “all-cause mortality” when compared to the non-underweight majority.
Though the majority of the underweight participants (89.9%) were women, the researchers noted that gender had no effect on this correlation between mortality and weight status.
Smoking status also had no effect, and authors noted that death by cancer, cardiovascular disease, and respiratory diseases was not observed in this population.
Study Finds Low Body Fat Compromises Immune Function
Admittedly, the direct connections between underweight status and infection risk are muddled by a swirling cocktail of mitigating factors like malnutrition, underlying conditions and treatments (e.g., chemo-related weight loss), and others.
Regardless of how they’re linked, a study from Innsbruck Medical University confirmed that underweight status and infection risk are indeed positively correlated.
After reviewing findings from both industrialized and underdeveloped nations, authors found a “u-shaped” rise in infection rates, denoting both underweight and overweight people experienced infections more frequently.
Considering the evidence in favor of fat’s ability to fight infection, this is a double whammy in the sense that underweight people may be both more prone to and less prepared for infections.
Hormonal Imbalances In Underweight Females
A finding from Ivane Javakhishvili Tbilisi State University in Georgia uncovered a number of troubling implications that being underweight has on reproductive health.
In the study, 48 underweight women and 55 overweight women were subjected to “clinical and hormonal analyses.”
The results indicated that both overweight and underweight participants had hormone imbalances that could affect their general and reproductive health.
Among underweight women, “non-classical congenital adrenal hyperplasia and ovarian dysfunction” were observed.
Congenital adrenal hyperplasia (CAH) refers to malfunction of the adrenal glands, which results in one or more imbalances in hormones produced by these glands (cortisol, aldosterone, and testerone, for example).
In other words, maintaining six-pack abs consistently instigates hormonal imbalances in women.
Planet Fitness Study Shows Women Prefer “Dad Bod” Over Toned Physique
Finally, we can’t ignore the sociocultural elements that motivate people to pursue six-pack abs, because realistically, many of us will jeopardize our health to appeal to the opposite sex.
But the ‘80s and ‘90s are over—terms like “dad bod,” “fat acceptance,” and “body positivity” are pinging around our increasingly connected social spheres.
Of all people, a study sponsored by Planet Fitness showed that modern women actually prefer the “dad bod” over toned abs.
Here are some of the most important takeaways from the 2,006-participant survey:
- 47 percent of all female respondents and 58 percent of mothers believe dad bods are the “new six-pack.”
- 78 percent of female respondents felt that the dad bod is a sign of confidence.
To clarify, we’re talking about a small-to-moderate amount of fat on an otherwise muscular frame here, not full-blown obesity.
Still, if sex appeal factors into your motivation to earn those washboard abs, it might be time to recalibrate for a new generation of women.
When Six-Pack Abs Aren’t so Bad
There’s no politically correct way to say this, but on a purely biological basis, six-pack abs aren’t as much of a health threat to men as they are to women.
Whether or not a woman intends to have children, her body will program itself to do so with essential fat stores, whereas the male body has a more primitive and minimalistic relationship with fat: stay warm, protect sensitive tissues, and facilitate the cellular functions mentioned above.
For this reason, men can drop further below the recommended body fat minimums for longer with fewer consequences.
Ectomorphic Body Type
Regardless of gender, a person who is lean by virtue of their body type and/or metabolism (and not because of dramatic “crash” diets and abusive cardio routines) is generally less likely to experience the above problems.
This body type is referred to as an ectomorph, which the Encyclopedia Britannica describes in their typically colorful prose as a “human physical type tending toward linearity.”
It may sound like a humble brag to the majority of us non-ectomorphs, but this is the person who often complains that they can’t gain weight, even with a 3,000-calorie diet.
Sure, they may experience some joint instability and other issues related to frailty, but it’s a markedly different situation than sweating yourself into an unnaturally low body fat percentage.
Temporary Weight Loss (Actors)
Here, we encounter a very fine line.
On the one hand, rapid weight loss is associated with hair loss, menstrual/hormonal irregularities, mononucleosis (“mono”), fatigue, and more.
On the other hand, high-profile athletes and actors with access to training staff, dieticians, etc. can usually drop down to a low body fat percentage with minimal issue.
This is because they’re still getting the macronutrients they need, and they can afford the products and services that make this transition a healthier one.
Most importantly, the fact that they often return to their natural weight after wrapping filming (or the season, competition, etc.) helps to soften the impact on overall health and longevity.
Redefining Core Strength for the Post-Abs Landscape
The ironic nature of six-pack abs is that, if you have to work to get them (i.e., they’re not consistent with your body type already), they may cause you some health problems.
For both the naturally six-pack-inclined and those who would strive to reach that hardly sustainable figure, we find that a focus on a strong core is better than the focus on a shredded core.
Beyond the “show” muscles that we know as the abs, there’s a deeper muscle called the transverse abdominis (TA) that bears great importance functionally (standing up, sitting down, breathing, walking, and much more).
Think of the TA as a belt that wraps around the spine to stabilize it—you can find quarantine-proof TA exercises here. By abandoning the campaign for six-pack abs and exercising the TA, your hips and glutes, and the paraspinals, you can achieve something much greater than a six pack: a strong core and confidence in your own skin.