Does our metabolism really slow down with age? (2021 study)

At the end of this month, I'll be 30 – that's right 30 YEARS OLD! I'm staring into the abyss of oldness and will shortly transcend my 20s. I know what you're thinking – it's all downhill from here. My metabolism will take a hit, and I will slowly or rapidly start packing on the pounds! Or will I?

Prefer to watch than read? Then please check out the video below:

Metabolism research

Does our metabolic rate really slow down as we hit 30, 40 or even 50 years old?  Hey, don't ask me – I'm not even 30 yet – what do I know!? Let's ask science – let's check out a 2021 study on 'Daily energy expenditure through the human life course' containing 6,421 subjects. Here's the data, and it's pretty evident, after adjusting for fat mass and fat-free mass, that from age 20 to 60, our metabolic rate and total energy expenditure stays super steady.

No drop at 30 (thank god), and not even a drop at 40 or 50. When it does start to drop, it's in our 60s, and even then, the drop is pretty steady, and I think I'm okay with not rocking abs in my 60s. 

I love studies like this! They let us know that we're not doomed to have a slower metabolic rate, and if you're already in your 40s or 50s, you're still benefiting from a decent metabolic rate, and even if you're over 60, it's really not that bad! 

'Andy, this is getting my nipples hard, but I know my metabolism's slower – I was super lean in my 20s, I eat the same, I still workout, but I continue packing on the pounds – my metabolism sucks!'

It’s not your metabolism slowing down – it’s your lifestyle!

Well, maybe it's not your metabolism – maybe it’s your lifestyle! Maybe, just maybe, you've steadily become more, and more, inactive – I know I have. I've gone from being an All Arms Physical Training Instructor in an infantry regiment – taking physical training multiple times per day. Then an in-person PT where I was on my toes all day, so still super active, and if anything, I struggled to eat enough. To then being an online coach – spending my entire week behind a desk. Don't get me wrong – I love it – I’m living the dream! But the reality is, I, as well as most other people, are becoming more and more inactive. If you've not adjusted your daily calories to account for the drop in activity levels, then you'll inevitably start gaining weight. This steady, but pretty substantial drop in activity levels as our lives become more comfortable does mean weight loss, or weight maintenance, gets harder as we age. Not only that, but our kids impacting our sleep, body aches and pains, sarcopenia (age-related muscle loss), pregnancy weight gain, and hormonal changes through menopause are all factors that can make things more challenging. 

But as we can see from the graphs, the biggest player – your metabolism is in a pretty strong position, so use that as motivation and work on correcting other things that might have regressed as we've aged. Are you less active? If yes, then get more active – cash in more steps, whenever you can. Have you lost some muscle mass? Well, let's correct that by rebuilding things in the gym. 

Knowledge is power!

Knowing that your metabolism isn't broken. Knowing it's probably the same as it was in your 20s. Knowing that it's ultimately you, your activity levels, and your habits that are really who's in charge of your physique – is very encouraging, empowering and motivating! 

Parting shot

Don’t allow your age to prevent you from achieving amazing results, whether you’re in you’re 20s or 60s, you have the ability to completely transform your physique – all you’ve got to do is want it and work hard for it!