Does Our Metabolism Die After 30?
4 weeks post-partum / 1 year post-partum
When I gave birth to my son, and I looked at my post-partum body in the mirror, I was sure I had just kissed my youth goodbye. That’s what everybody said. Your hips will widen, your belly will forever bulge, and your metabolism will be so slow that if you inhale anything other than air, you will gain fat…
The pressure to bounce back into your pre-baby body is so intense, and the comparison game becomes so toxic. You look at Stacey, who could feed a village with her milk supply, draining the pounds away while nursing her perfect baby. And then you look at yourself, your breasts drier than the lime wedges they give you at the Mexican restaurant, unable to fit into your old clothes and feeling like this is your new reality. Forever.
We Millennials have a plethora of jokes about how our knees and backs are cracking, our livers can’t keep up anymore with our college drinking habits, and being asked to go out of our house past 9 pm is an insult…because the reality of our bodies changing with the decades is real, and nobody prepared us for the absolute train wreck it was going to be. Feeling tired, grouchy, stressed, overworked — and underpaid — are the staples of adulthood in a world that feels less and less like it gives a damn about us.
When the 30s hit with the full weight of parenthood and careers, things like staying physically active or losing accumulated weight feel like gargantuan tasks. Not only because our bodies seem to fail us but because we’re immersed in a culture and system that make the fostering of positive, healthful habits a chore rather than an engrained part of who we are. In juxtaposition, there is an unrealistic societal demand to look and live like actors in tv commercials, with the perfect bodily ratios and an overall appearance of having our shit together. Anybody would resent that.
But how much truth is there in the generalized idea that once we hit this seemingly dreadful age, our bodies truly shut down? What is a metabolism anyway?
The incredible human machine is run by constant chemical interactions. The endocrine system is a complex network of glands and organs that produce and release hormones. These chemical messengers regulate various physiological functions and maintain homeostasis (balance) in the body. These hormones travel through the bloodstream to target cells, influencing metabolism, growth and development, immune function, mood, and reproduction. The endocrine system is crucial in coordinating and controlling numerous bodily functions, ensuring that the body's internal environment remains stable and functions optimally.
Metabolism is the combination of all the chemical processes that allow an organism to sustain life. For humans, this includes conversion of energy from food into energy for life-sustaining tasks such as breathing, circulating blood, building and repairing cells, digesting food, and eliminating waste. - Fatima Cody Stanford, MD, MPH, MPA, FAAP, FACP, FTOS, Harvard Health Publishing
For a long time, there was a widely accepted belief that metabolism began to progressively slow down sometime between your 20s and 30s, meaning that with each passing year and decade, our ability to burn energy became slower and slower. This is when most adults in the Western world have established careers and school-aged children and when most people begin to notice that losing weight is not as easy as it used to be. However, the most recent research on Total Energy Expenditure (TEE) challenges this preconception. One of the main takeaways of this large study by Pontzer et al. is that metabolism peaks in adulthood but remains stable throughout middle life (the 20s to 60s) and then declines after older adulthood.
19 years old / 32 years old
So, if it’s not a slower metabolism, then what is it? Is it all in our heads?
No, it is very much real, but it doesn’t seem to be good ol’ metabolism’s fault for most otherwise healthy adults. The hypothesis is that priorities compete as we age, become parents, and work to make a living. Do we hit the gym, run some laps after work, or unplug on the couch and scroll on our phones? Do we wake up at the crack of dawn and log some miles on the bike, or do we wash sheets covered in vomit from the latest stomach bug circulating at our kids’ school? What about social life? Sometimes, it’s almost like we have to choose between seeing friends and having a good time over a few glasses of wine, over meal-prepping and sticking to the low-carb diet everybody is doing (I will tell you my beef with low-carb diets in another article.)
The above are oversimplified examples, but they are glimpses of the things that compete for time that we could otherwise spend taking care of ourselves in the ways doctors and health professionals recommend. Most Americans “fail” to meet the minimum requirements of weekly physical activity and nutritional guidelines. Still, I find failing not to be the appropriate word. If anything, I believe that we are being failed to. Without removing the accountability each individual has over their own well-being, we need to consider that we as persons are fighting a machine of misinformation, anti-science, and pro-profit food, healthcare, and wellness industries.
Food companies engineer products that distort our palate and make us crave more, market them into every waking hour of our lives, and successfully make them part of the culture. Healthcare and insurance systems make it a hassle and sometimes prohibitively expensive to get proper guidance on our metabolic health. Disappointed people then turn to quacks who peddle pseudo-science, eroding trust in evidence-based medicine and giving rise to uncredentialled wellness authorities with millions of followers, who then are told to fear every foodstuff, buy their supplements and follow alternative treatments and weight-loss programs instead.
Let’s find, then, a bit of liberation in the fact that we aren’t just rotting away into old age. Our metabolism can perfectly support whatever aspirations we may have regarding our bodies, at least from an energy standpoint, whether to become a later-life athlete or simply be able to do things you used to and not want to die. Made-up ailments like adrenal fatigue are not the culprit of what is making us feel like dog turd. Pregnancy and the post-partum, while a beautiful nightmare, are not dooming us women into oblivion. Even premenstrual syndrome and menopause are manageable nowadays, thanks to advances in modern medicine. However, taking ownership of our well-being in this world and age is tough and confusing. The only way around that is to stay educated, trust science, and get proper guidance.
Don’t let anybody tell you you’re “too old” to do whatever you want. Your body’s got you. All it asks for is a little love and care in return.