Hitting your 40s is often a brilliant, confident time of life, but it’s also a decade where your body’s internal chemistry starts to undergo some massive changes.
It’s easy to write off daily fatigue, sudden mood changes, or a sluggish metabolism as just the natural price of getting older or dealing with a busy schedule, but beneath the surface, your hormone levels, metabolic health, and nutrient absorption are entering a completely new phase that requires much closer attention.
Relying on standard checkups isn’t always enough to spot potential issues before they turn into chronic problems. Keeping a close eye on a few specific, vital blood markers is the smartest way to take control of your long-term well-being and ensure your body has exactly what it needs for the years ahead. Here’s what you should be asking your GP to check out.
Midlife is the perfect time for a proper health audit.
Perimenopause and the years that follow can throw up an exhausting list of symptoms. Crushing fatigue, brain fog, broken sleep, anxiety, weight changes, low mood and sudden dips in energy that make you feel like a completely different person. The frustrating part is how often these symptoms get brushed off as being normal and no big deal, when in reality, there are several important health markers worth checking properly.
Women are often very good at soldiering on through symptoms, but issues like low iron, thyroid problems or poor blood sugar control can creep up during midlife and massively affect how you feel day to day. A few routine blood tests can shed real light on what’s happening inside your body, and help you make more informed decisions about your health going forward. It’s a piece of self-care that often pays off in ways you wouldn’t expect.
Ferritin, iron and haemoglobin
Heavy or more frequent periods during perimenopause can leave many women genuinely depleted of iron without realising it. Low iron stores can cause fatigue, dizziness, poor concentration, breathlessness, hair shedding, restless legs, itchy skin, anxiety and that constant wiped-out feeling that just won’t go away. It’s also one of the most commonly missed reasons for women feeling rotten in midlife.
Ferritin is the most important marker here because it reflects your stored iron levels rather than just what’s circulating in your blood that day. You can technically be within the “normal” range and still feel awful if your stores are scraping the bottom. It’s worth asking your GP for a copy of your results so you can see the actual numbers rather than just being told everything is fine.
Foods rich in iron include red meat, lentils, tofu, beans, dark leafy greens and fortified cereals. Pairing plant-based sources with vitamin C-rich foods boosts absorption, while avoiding tea or coffee with meals also helps. In some cases, you may need supplements or even an IV infusion to properly rebuild your stores.
HbA1c
HbA1c is a blood test that gives an overview of your average blood sugar levels over the past three months. It’s particularly useful because it picks up insulin resistance, pre-diabetes and type 2 diabetes risk long before you’d notice any obvious symptoms. For women in midlife, this matters more than it might at first appear.
Hormonal changes, loss of muscle mass, poor sleep and increased belly fat during menopause can all affect blood sugar regulation. The result is more energy crashes, stronger cravings, persistent hunger and that constant urge to snack. Women often blame themselves for lacking willpower, but unstable blood sugar can have a huge impact on appetite and energy.
Building meals around a palm-sized portion of protein, plenty of fibre-rich plants and a small amount of healthy fats can help support steadier glucose levels throughout the day. A simple HbA1c gives a far more meaningful picture of what’s actually been happening with your blood sugar over time than the trendy continuous glucose monitors being marketed to people without diabetes.
Cholesterol
Cholesterol levels often rise after menopause due to falling oestrogen levels, even in women who eat well and exercise regularly. While cholesterol itself isn’t something you can feel, elevated LDL cholesterol is one of the biggest risk factors for cardiovascular disease, which becomes a much bigger issue for women in midlife and beyond. Heart disease in women is hugely under-discussed, and getting a proper read on your cholesterol is one of the simplest ways to stay ahead of it.
The conversation around menopause needs to include heart health far more than it currently does. Women are often shocked when cholesterol rises seemingly out of nowhere in their forties and fifties. Increasing your intake of viscous soluble fibre from foods like oats, beans, lentils, chia seeds, flaxseeds, and barley can help support healthier cholesterol levels. This needs to sit alongside regular movement and a generally good diet, but small dietary tweaks can make a real difference without needing medication for many women.
Thyroid function (TSH and T4)
Thyroid problems become increasingly common in women as we age, yet the symptoms overlap heavily with perimenopause, which is exactly why so many cases get missed. An underactive thyroid can cause fatigue, weight gain, constipation, low mood, dry skin, brain fog and hair thinning. Sound familiar? It’s not surprising that women are often told they need to “accept feeling tired and sluggish” when the real issue is a thyroid that needs medical attention.
If something feels properly off, ask your GP for a thyroid function test that checks both TSH and T4 levels. If you’re diagnosed with Hashimoto’s, an autoimmune thyroid condition, you’ll likely need thyroxine medication, which can help you feel completely back to normal. Nutrition won’t cure a thyroid condition, but eating enough protein, iodine, selenium, and iron can support normal thyroid function alongside any treatment prescribed by your doctor. The improvement once a thyroid issue is properly treated can be genuinely life-changing.
Vitamin D
Vitamin D deficiency is incredibly common in the UK, particularly during autumn and winter when sunlight is in short supply. Even low levels, under 50 nmol/L, can contribute to fatigue, low mood, muscle aches and poorer bone health. This becomes even more important during and after menopause, when falling oestrogen levels increase the risk of bone loss and osteoporosis.
Vitamin D is one of the nutrients that comes up most often in midlife health conversations. It plays a key role in immune health, muscle function and bone health, all of which become increasingly important as we age. The problem is that it’s pretty much impossible to get enough vitamin D from food alone, which is why people in the UK are advised to consider a supplement during the winter months.
The recommended dose is 10mcg, or 400IU, but you may actually need more depending on your levels. That’s why knowing your numbers through a blood test really matters rather than just guessing.
The non-blood test everyone should know about
Blood pressure might not involve a needle, but it’s one of the most important health checks women over 40 should be keeping an eye on. High blood pressure often has no obvious symptoms, which is why it’s sometimes called a silent risk factor. Hormonal changes, stress, poor sleep, weight gain and genetics can all contribute to it creeping up without you noticing.
The good news is that lifestyle changes can make a meaningful difference. Regular movement, cutting back on excess alcohol, improving sleep quality and eating a diet rich in fibre, potassium and minimally processed foods can all help support healthier blood pressure. Most GP surgeries will do a blood pressure check for free, and you can buy a decent home monitor for around £30 if you’d rather keep an eye on it yourself between appointments. It’s one of the easiest health markers to track, and one of the most important.
How to get these tests done in the UK
Most of these tests are available through your GP, although getting them all in one go can sometimes require a bit of persistence. If you’re experiencing symptoms, it’s worth booking a proper appointment and explaining what’s been going on, rather than ticking the box at a standard check-up. Some GPs are brilliant at ordering comprehensive bloods, while others may need a bit of polite pushing to look beyond the basics.
For those who’d rather skip the wait, private blood testing has become much more affordable and accessible in recent years. There are several companies offering at-home finger-prick tests that cover all five of these markers, with results delivered within a few days. Prices typically range from £50 to £150 depending on what you include, and you can usually share results with your GP afterwards if anything needs follow-up. For women whose GP isn’t keen on extensive testing, this can be a useful workaround.
