Are DIY home health test kits worth it?

From hormone levels to cholesterol, vitamin D, iron deficiency and more – you can now buy one-off home testing kits to check for a huge range of health issues. 

But, while the idea of a quick check for reassurance might seem convenient, you might find yourself left with more questions and less cash – or, concerningly, falsely reassured that everything's fine when it isn't. 

Since 2020, when millions became used to self-testing due to the pandemic, DIY test kits that promise to diagnose everything from thyroid issues to bowel cancer have become increasingly mainstream. 

The NHS is also making more use of home test kits for certain health screening checks, which can be more convenient and improve take-up rates.

But with some private self-test kits costing hundreds of pounds, it's worth knowing the limitations of going it alone. 

Several studies, including a previous Which? investigation in 2020, and more recently research published in the British Medical Journal (BMJ) in July 2025, have warned that relying on self-testing can be risky. 

Bear in mind that any tests you really need should be available free via your NHS GP. And if a test you do at home requires further action or NHS treatment, you'll need to follow up with your GP and possibly do the test again anyway.

What health self-testing kits are available?

A quick google or browse of your local pharmacy or supermarket will reveal a wide range of self-test kits available to buy. 

There are at-home test kits for cholesterol levels, STIs, blood glucose levels, prostate health and fertility and hormone tests, among many others. 

Boots has its own range which includes rapid tests for vitamin D and iron levels, while Newfoundland offers a huge range of tests from Coeliac disease to HIV testing and dozens of other conditions (largely available in Tesco). Standalone brands like Numan, Thriva, Randox and more also crop up online.

These kits can cost anything from a few pounds for the most basic checks to hundreds of pounds for more comprehensive lab-tested blood samples. 

Some, like a pregnancy or Covid test, will give you a speedy result at home, while others need to be sent as a blood or cheek swab sample to a lab for analysis and may involve a follow-up chat with a health professional.

Pros and cons of home testing kits

Depending on what they are testing for, some test kits will give you a simple indicator, usually of whether a certain marker level is raised or not and whether this falls between expected levels, for example vitamin D levels or cholesterol. These are relatively simple to interpret (though still not foolproof). 

Others will give you reams of complex information that isn't necessarily easy to unpick, or explained fully. Some brands charge extra for a consultation to discuss the results.

When we asked health experts to analyse a range of self-test kits back in 2020, they were unimpressed. One of the main issues is that the test is a blunt tool, and you may not be applying it correctly, or even know what needs checking most. 

One GP told us: ‘Interpreting bloods is a real art and needs to be done in the context of why they were ordered and what else is going on.’

One diabetes test kit we analysed, for example, didn’t address non-blood-related symptoms of the condition in the user information pack. If someone's blood test looked OK, they might not seek further treatment, which could be dangerous. 

The risk of false reassurance is a real problem. If you've gone to the trouble of purchasing and taking a test, you are probably worried about a specific problem. But getting a normal result from one test doesn’t necessarily mean there’s nothing wrong – it could have been the wrong test for you. 

Equally, if you do receive an abnormal result from an at-home testing kit, it may not in fact be any cause for alarm and could cause much more worry than necessary. 

If you do receive a test result that requires further investigation, it's likely you'll need to follow up with your GP anyway. And they will need to run their own tests to confirm any private results, so it won't necessarily save you any time in the long run.

2025 study raises fresh concerns about regulation of self-test kits

A 2025 study by the University of Birmingham, published in the BMJ, renewed concerns about issues with self-testing kits, warning that while many of these kits carry claims of very high accuracy rates, the supporting evidence is often not publicly available. 

The study looked at 30 self-test kits priced between £1.89 and £39.99, and noted that only eight provided information about who should or should not use the test, while four specified the presence of symptoms. 

Sue Davies, Which? policy expert, said: 

'Consumers should be careful with self-tests – they can be expensive, tricky to interpret and don't always come with an expert consultation to help you understand your results.

It's also likely you'll need to follow up with your GP if you receive an abnormal test result, so we would always recommend involving them from the start if you have any particular health concerns. 

Most tests you'll need will be available for free on the NHS and your GP will also be able to speak to you about how you're feeling and spot any symptoms that might not show up on a test.'

Best cholesterol monitors - we lab-tested a range of products against an industry standard device. Only one brand impressed enough on both accuracy and quality of the advice given to get our recommendation. Seven were so inaccurate we've named them Don't Buys

Are self-test kits worth it?

Testing yourself at home can certainly be a convenient and quick option, and the NHS itself is making more use of home kits to screen for bowel cancer and STIs. 

If you're struggling to be heard on a certain issue, it can be handy to have backup too. But losing the context of discussion with a health professional before and after can limit its usefulness and leave you out of pocket. 

Professor Jon Deeks, from the University of Birmingham, who conducted the 2025 study, explained: 'While these kits have been approved for sale, they are not subject to the same stringent regulations as pharmaceutical products. 

'Our recent research raises concerns about the suitability, accuracy and usability of many of the self-testing products available that require users to sample, test and interpret results themselves.'

If you don't feel like your health concerns are being heard, don't be afraid to raise this with your doctor's surgery. See our guide to getting the most from your GP

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Free health checks you can get on the NHS

A range of home self-tests are available for free as part of NHS initiatives or screening programmes for certain age groups, including:

• NHS bowel cancer screening Available for people aged 50 to 74. Eligible people will be sent a kit in the post.
• STI tests At-home STI test kits are provided by different organisations in different areas, such as Sexual Health London and SH:24

Over-40s can make use of the NHS Health Check, also known as the 'health MOT'. It's an in-person check at your GP surgery and is available to people aged 40 to 74. 

It checks your risk levels for common later-life health issues including heart disease, diabetes, kidney disease and stroke, and includes a cholesterol test, blood pressure check and may include a blood test. You can have a repeat one every five years.

Many pharmacies, including some supermarket ones, will also do free blood pressure checks for anyone eligible (usually if you're over 40 years old).

Other screening tests done at health centres include cervical screening, breast screening and AAA screening. You can find out more on the NHS screening guide.

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