What are "general health blood tests" and when do you need to take them?

Want to live a long and healthy life? Testing and tracking your key health biomarkers is a “must”.

Medical review by

Dr Alasdair Scott MBBS FRCS PhD

gut doctor, PhD and our research director


Key Takeaways

  • Heart disease, stroke, dementia and cancer all take years - often decades - to develop.
  • But the problems that cause these conditions start early, in our 20s, 30s and 40s.
  • Testing and tracking your health markers over time is the only way to know if your health is on the right path to prevent disease.
  • You should regularly test your cholesterol, HbA1c sugar-handling, liver, kidney, thyroid and essential nutrients with our General Health and Lifestyle Blood Test.

Your health is the most precious gift you’ll ever have and yet, for many of us, the first time we really pay attention to it is when something goes wrong. But if you want to live for as long as possible, in as good health as possible, then you need a more proactive approach. We’ll go through why general health blood tests are important and what they can tell you.

If you don’t test you won’t know

Checking and testing before things go wrong isn’t a new idea. After all, we do an MOT on our car every year. We understand that some problems don’t show any signs until it’s too late and that it’s easier, cheaper and safer to fix them before they get to this point.

But why don’t we take this approach with our health? The major causes of death and poor health in the UK are heart disease, diabetes, cancer and dementia. But none of these happen overnight. They take years (often decades) to develop. Your health in your twenties, thirties and forties has a huge impact on how likely you are to develop these conditions in later life. Sure, you feel fine now, but what’s actually happening inside your body?

Blood tests can give you a snapshot of what’s going on with your general health. Even more importantly, by tracking your markers over time, you can see what path your health is on and predict the future. Figure 1 shows four “normal” HbA1c results in someone who’s testing every 4 years. All good, right? Wrong.

These results show a clear path towards diabetes and all the problems it causes. But the future isn’t set in stone. You have the power to change course. But if you don’t test you won't know what path you’re on.

HbA1c health trajectory
Figure 1: Diabetes risk over time. Haemoglobin A1c (HbA1c) tells us your average blood sugar levels in the last 2-3 months. If your HbA1c levels are creeping up slowly over the years when you test, you can predict the path towards pre-diabetes and diabetes.

What are the key biomarkers to test for in a general health check?

Exactly what to check may depend a little on your age and past medical history, but there are some key biomarkers that we should all check regularly. This is because they tell us about our major body systems and often show abnormalities well before any symptoms start.

We recommend checking your HbA1c sugar-handling, cholesterol levels, liver, kidney, thyroid and essential vitamins and minerals. We include all these tests in our General Health and Lifestyle Blood Test.

HbA1c sugar-handling

The HbA1c test shows you how your body is handling your blood sugar. Diabetes is a condition where your body can’t handle blood sugar properly and it’s associated with a lot of medical problems like heart disease.

But you might not know that, although diabetes is at one end of the scale, HbA1c is really a continuum from good to poor sugar-handling. In general, a lower HbA1c is associated with better health. Even before you get to diabetic levels, a higher HbA1c has been shown to increase your risk of developing heart disease1, cancer2 and dementia3.

Lipid profile (cholesterol and triglycerides)

Your lipid profile (the level of cholesterols and triglycerides in your blood) is an important risk factor for heart disease, stroke and dementia; three of the top ten causes of death globally4.

When it comes to cholesterol levels, “normal” isn’t good enough. You need to be aiming for “optimal” levels to have the best chance of living better for longer. But there’s no way to know your cholesterol levels unless you test them.


Thyroid health

Your thyroid gland is involved in your metabolism and affects nearly every part of your health, from your cholesterol to your gut and even your skin. Thyroid conditions can start at any age. Some 5% of the general population have an underactive thyroid and another 5% are thought to be undiagnosed5. Thyroid-stimulating hormone (TSH) is the main biomarker in your blood for checking your thyroid health.

Thyroid gland

Liver health

Your liver filters, processes and metabolises nearly everything you put into your body. While you probably know that alcohol can injure your liver, did you know that fat build up in the liver can do the same damage? So-called non-alcoholic fatty liver disease is fast becoming one of the commonest reasons for people needing a liver transplant.

Checking the levels of your liver enzymes and proteins can give you an indication of liver health well before any permanent damage occurs.

Kidney health

Your kidneys filter waste from your blood and help to keep your body fluids and minerals in balance. Some 15% of people aged 35 and above have chronic kidney disease (CKD)6, which is where the kidneys don’t function as well as they should. Common causes are diabetes and high blood pressure. CKD doesn’t come with symptoms until it gets more advanced, which is why it’s important to check your kidney health regularly.

Iron status

Iron is a vital nutrient which helps to make a protein in your red blood cells called haemoglobin that carries oxygen around your body. If you aren’t getting enough iron in your diet, your body can’t make enough haemoglobin and you’ll become anaemic. People on a plant-based diet are at particularly high risk.

You can also become iron deficient if you’re losing blood. This is common for women before the menopause but it can also happen with bleeding from the gut, which can be an early warning of bowel cancer.


Calcium is important for your bone and muscle health and most of us get plenty in our diet without even thinking about it. But did you know that calcium levels can also be a sign of some cancers and serious disease? That’s why it’s important to keep an eye on your calcium levels every now and then.

Vitamin D

Vitamin D deficiency affects 1 in 6 people in the UK8. Vitamin D is important for your bones and immune system, as well as regulating calcium and phosphate levels in your body. We don't get enough sunlight in the UK so we're all at risk of deficiency.

Sunshine vitamin D

Vitamin B12

Vitamin B12 is involved in making your red blood cells along with having other important functions in your body. Low vitamin B12 levels can lead to anaemia, where you can feel run-down, tired and be more prone to getting infections. If you’re a vegetarian you’re more at risk of vitamin B12 deficiency than meat-eaters. People on fully plant-based diets are at even higher risk, with 50% of vegans likely to be deficient9.

How can you test your general health?

Testing the above body systems, vitamins and minerals will ensure that you’ve covered all the bases to keep tabs on your general health.

Our General Health & Lifestyle Blood Test can check all of these things with a simple at-home blood test. This panel tests for all the key indicators of the major body “systems”. If something isn’t as it should be, these biomarkers often give a warning sign before you have any symptoms at all.

Simply take your sample at home and post it to our lab for analysis. Our doctors will write you a detailed report to help you understand your results along with recommendations on what to do to optimise your health.

General Health and Lifestyle Blood Test

When and how often should you test your general health?

When and how often you test your general health is a balance between your risk, the cost of testing and how quickly these markers change. In general, the older you are, the higher the risk of your health going off track. But you might also have some personal risk factors - family history, eating a plant-based diet, being overweight - that you need to take into account.

The National Heart, Lung and Blood Institute in the USA have guidelines10 on testing your cholesterol levels that are a sensible starting point for other general health tests, too:

AgeHow often to check your general health
20 - 40Every 5 years
40 - 60Every 1-2 years
60 plusEvery year
Table 1. How often to check your general health based on your age.

If any of your markers are abnormal (or not optimal) then of course you should test more frequently. In general, it’s worth waiting 6 months between testing because it often takes time for your markers to shift when you make lifestyle changes.

Keep your health on track

What if my general health is going off track?

If you’ve taken our General Health and Lifestyle Blood Test and your health isn’t where it should be, there will be next steps you can take to improve your health.

Sometimes it’s just a case of getting more of a particular nutrient in your diet or considering supplements. Other times there may be a specific issue that needs further investigation or management by your doctor.

However, a lot of the time, it’s your lifestyle that needs to change to get your health back on track. While we can (and do) make recommendations about your diet, exercise and sleep, there’s only so much we can tell from tests alone. To really help you, we need to get to know you.

That’s where our Health Reset program comes in. In this 12-week program we deep-dive on your health and wellbeing and come up with a plan to optimise your exercise, diet, sleep, mental health and engagement. What’s more, your health coach will give you the support and accountability to put your plan into action.

If you’re interested in becoming your healthiest self, book a free discovery call today to find out how we can help you.

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