Being healthy from a body composition standpoint likely means staying between 8 to 17% body fat for men and 16 to 30% for women (1). There will be exceptions to these rules, but right now these are the best lines in the sand that we have.
These numbers are likely a lot wider than you had in your head and if you combine these ranges with a sufficient amount of muscle mass (2) to keep you functional in life and metabolically flexible we have arrived at some solid landmarks for health.
Most people (not all) that you see on Instagram with insanely chiseled abs are very likely NOT healthy. In fact, if you take their blood work they may even be told to seek immediate medical attention.
The vast majority of humans probably can’t and shouldn’t maintain resting eight packs all year long.
If we look at Pontzer’s data on the Hadza hunter gathers we see that males were 13.5% body fat on average and females were 20.9%, but the spread was around 5% in both cases (3).
Even with this small sample size, this is a range I can get behind when we define health. These ranges are also supported by the 2017 paper by Maffeton et al. which unfortunately found that statistically, 91% of the US population is OverFat (1).
When you are happy with your body and are living inside these ranges then we need to MAXIMIZE food consumption because in reality that is the HEALTHIEST choice one can make.
For females, this looks like an energy availability of around 45 calories per kilogram of fat-free mass and for males it may be a little lower at 40 kcal/kg of FFM (4). Eating more while staying weight stable is most always probably a good thing.
Energy availability is a fancy pants research term that means how many calories you need BEFORE taking into account exercise divided by how much fat-free mass you have (muscle, bone, organs etc).
For example, if we have a 155-pound female who is 28% body fat eating 1,500 kcals and burning about 250 kcals in exercise per day that would equal an energy availability of 24.6 kcal/kg.
Thus, long-term this is NOT a viable solution.
I get visibly angry at the number of women who have been put on 1,200-calorie diets that never end. How did 1,200 become the number anyways?! Ridiculous.
“In females, many physiological systems are substantially perturbed at an energy availability of <30 kcal/kg FFM/ day.” [this is probably <25 kcal/kg FFM/ day for males given we don’t directly turn calories into baby humans and males are far more expendable]
-Mountjoy et al. 2018
Eventually, we need to rev the system and for this same female above that likely equates to more than 2500 kcals per day!!!!
Say it again for the people in the back. 2,500 kcals.
We need to stop asking our bodies to make choices between adaptation and survival…
Because survival will always win.
Living your life in a low-energy non-adapting state because…social media sounds pretty terrible and is NOT at all healthy.
Everything has a cost, but most people are unaware of the price tag.
If we are after health, a six-pack 100% is not necessary and in many cases, living too lean may even be inadvisable.
So let’s work to define what healthy looks like for YOU and once we get there we need to flip the switch to eating MORE not less.
1. Maffetone PB, Laursen PB. The Prevalence of Overfat Adults and Children in the US. Front Public Health. 2017;5:290.
2. Abramowitz MK, Hall CB, Amodu A, Sharma D, Androga L, Hawkins M. Muscle mass, BMI, and mortality among adults in the United States: A population-based cohort study. PLoS One. 2018;13(4):e0194697.
3. Pontzer H, Raichlen DA, Wood BM, Mabulla AZ, Racette SB, Marlowe FW. Hunter-gatherer energetics and human obesity. PLoS One. 2012;7(7):e40503.
4. Mountjoy ML, Burke LM, Stellingwerff T, Sundgot-Borgen J. Relative Energy Deficiency in Sport: The Tip of an Iceberg. Int J Sport Nutr Exerc Metab. 2018;28(4):313-315.