7 signs of ageing and the blood values behind them

The signs of ageing tend to creep in around 40, so gradually that you often only spot them in hindsight.

What strikes me: most articles list the signs neatly and leave it there.

I find that a shame, because behind every sign sits biology, and sometimes a blood value that says something about it.

For a few signs there is no blood value at all, and I will be honest about that.

What are the first 7 signs of ageing?

The first signs are subtle: less energy, slower recovery after sport and more brittle bones. Then come a fuller belly, thinner skin, worse sleep and a quiet inflammation. Together those seven signals form the story of ageing, and some show up in your blood.

Sign one is energy. You notice that an ordinary workday feels heavier around three in the afternoon than it used to.

Sign two is slower recovery. After a hard training session or a day of chores, the stiffness lingers longer.

Sign three is your bones. They grow less dense over the years, something you often only feel after a fall or a fracture.

Sign four is belly fat. A little gathers around your waist over time, even when the scale barely moves.

Sign five is your skin. Skin is where many people notice ageing first: thinner, drier and lined.

Sign six is your sleep. You wake more often, and the deep sleep of your twenties comes back less easily.

Sign seven you do not see and barely feel: a quiet, low-grade inflammation that rises with age. Researchers call this inflammaging.

Which signs can you see back in your blood?

Five of the seven signs have a blood value that can say something about them. For energy you look at ferritin, B12 and TSH, for bone loss at vitamin D, and for belly fat at HbA1c. The quiet inflammation, finally, is measured with hs-CRP.

Start with energy, because for many people that is where the most is to be gained. A low iron store, a vitamin B12 shortage or a slow thyroid often feels identical: flat and tiring faster. Ferritin, B12 and TSH can give direction here, though your GP decides what a value means in your case.

When fatigue lasts a long time, it can help to know which shortages play a part. In recognising vitamin deficiency symptoms you can read which vitamins people often have checked.

Your muscles are a trickier story. From roughly age 30 muscle mass declines gradually, and that decline can speed up later in life into sarcopenia (PMID 30312372). No direct blood value for muscle mass exists, but you notice it in slower recovery and less strength.

Bones and vitamin D belong together. Vitamin D plays a role in the uptake of calcium, and in the Netherlands a lower vitamin D value in winter is not unusual. Thuisarts describes in plain language who has a greater chance of a shortage.

If you want to know which values relate to your bones, read preventing osteoporosis with vitamin D and calcium.

Belly fat looks harmless, but it is metabolically active tissue. As more fat gathers around your organs, your body can handle sugar less smoothly. HbA1c gives a picture of your average blood sugar over the past weeks, and glucose of the moment itself.

Then the sign you do not see: inflammaging. Over the years the level of low-grade inflammation slowly rises, and that process is linked to cardiovascular disease and frailty (PMID 30065258). hs-CRP is a sensitive inflammation value that can catch a glimpse of this.

If you want to know what that value is exactly, look at the marker hs-CRP (high-sensitivity CRP). How your blood relates to your calendar age sits in what your blood reveals about your biological age.

Which signs say nothing about your blood?

Two signs will not be caught in a tube: your skin and your sleep. Wrinkles form because your skin makes less collagen, and there is no blood value for that. Worse sleep often has to do with lifestyle and your body clock, not with one measurable substance.

Take the skin. Research shows that collagen production in ageing skin declines, partly because skin cells do their job less well (PMID 16723701). No supplement and no blood test changes that number, however much we might wish it did.

I find it more honest to say that than to pretend a marker for wrinkles exists.

Sleep is just as little a blood value. The structure of your sleep changes with age: you wake more often and deep sleep grows shorter. What does help lies mostly in rhythm, light and movement, and you discuss that better with your GP than with a lab.

More on energy and sleep as you age sits in staying vital with age: energy, sleep and the blood values you can check.

What do you do with these signals?

Start by writing down which sign occupies you most, and since when. Take that story to your GP, who can place a complaint that a single blood value cannot. If you want a measured starting point, you can have several of these values drawn.

My advice stays plain. A blood value is a snapshot, not a verdict on how old your body is.

If you want to look at several of these values at once, an extended health checkup brings ferritin, HbA1c and inflammation values into view, among others.

For the broader background by age, read which blood values to monitor from your 40s.

Does something swell up, do you lose weight unexpectedly, or does fatigue last for weeks? Then that story belongs with a doctor, not with a search engine.

References

1. Ferrucci L, et al. Inflammageing: chronic inflammation in ageing, cardiovascular disease, and frailty. Nat Rev Cardiol. 2018;15(9):505-522. PMID 30065258.
2. Cruz-Jentoft AJ, Bahat G, Bauer J, et al. Sarcopenia: revised European consensus on definition and diagnosis. Age Ageing. 2019;48(1):16-31. PMID 30312372.
3. Varani J, Dame MK, Rittié L, et al. Decreased collagen production in chronologically aged skin. Am J Pathol. 2006;168(6):1861-1868. PMID 16723701.
4. RIVM and Thuisarts. Public information on vitamin D, ageing and health. Available via rivm.nl and thuisarts.nl.

Every blood test result at Vitalcheck includes a professional assessment by a BIG-registered doctor. A blood value is not a diagnosis: always discuss treatment decisions with your GP.