Are Hair Intolerance Tests Accurate? An Honest Answer

This page answers the question most people ask in the last minute before they order: does a hair-sample intolerance screen actually work? The honest answer has two halves and we will give you both. Hair screening is not a validated diagnostic method, it is not endorsed by the NHS, NICE, the British Dietetic Association or Allergy UK, and published critical reviews of hair and bioresonance testing have found that it does not reliably identify food intolerances. What it does produce is a structured shortlist — and a shortlist is what turns a six-week elimination diet from an impossible guessing game into something you can actually run. Everything below explains exactly where that line sits, so you can decide with the facts in front of you rather than after the fact.

What this screen is — and what it is not

What it is

• A hair-sample screen across 700+ items on the Gold report at £49 (350 foods and drinks plus 350 non-food items), or the top 100 items on Silver at £37
• A personalised report that groups entries generated by the proprietary, non-diagnostic process into a shortlist worth exploring first
• A structure for a six-week elimination and a staged reintroduction — the part that does the real work
• Emailed within 3 working days of your sample arriving at our UK lab (allow 5–7 days from posting, because the post is not ours to promise)
• Covered by a 90-day money-back guarantee, with the conditions stated openly: follow the plan for 6 weeks and keep a food diary

What it is not

• NOT a diagnostic test. It cannot diagnose, treat, cure, relieve or prevent anything
• NOT a validated method. There is no robust published evidence that hair screening identifies which foods do or do not suit you
• NOT recognised or recommended by the NHS, NICE, the British Dietetic Association or Allergy UK
• NOT an IgE allergy test. It does not measure antibodies, and it says nothing about immediate or severe allergic reactions
• NOT a coeliac test, a lactose-intolerance test or a test for any other named condition — those need your GP
• NOT proof of anything on its own. The report does not demonstrate a link between a food and how you feel; only your own elimination and reintroduction can start to do that

The evidence position, stated without spin

We are a business selling a screen, so you are right to discount what we say about it. Here is the position anyway, put as plainly as we can manage.

Hair-sample and bioresonance-style intolerance screening has not been shown to work in the way a clinical test is expected to work. Reviews published in the scientific and dietetic literature have looked at commercial intolerance testing of this kind and reported the same broad findings: the results do not reliably match what people actually react to, different samples from the same person can return different item lists, and there is no established biological mechanism that would explain how a food intolerance leaves a readable signature in a strand of hair. None of the UK bodies that assess this sort of thing — the NHS, NICE, the British Dietetic Association, Allergy UK — endorse it. Several of them advise explicitly against relying on commercial intolerance tests.

We are not going to argue with any of that, because it is correct, and because a company that argues with the evidence is telling you something about itself. The useful question is not “is the screen accurate?” It is “what is a shortlist worth, if a shortlist is all it is?” That question has a real answer, and we come to it below.

Why “accuracy” is a harder word here than it looks

Accuracy is measured against a reference standard: a test is accurate if it agrees with something already known to be true. For food allergy, that reference exists — specific IgE, skin-prick testing and supervised food challenge, all arranged through a clinician. For food intolerance, it largely does not. There is no single blood marker, scan or biopsy that establishes an intolerance for most foods. The nearest thing to a reference standard is a carefully run elimination followed by structured reintroduction, ideally supervised by a dietitian, and that is a process, not a laboratory value.

So when any company — us included — quotes an accuracy percentage for an intolerance test, ask what it was measured against. We do not quote one, because we cannot defend one. What we can tell you is what the screen physically does, what it cannot do, and what you would need to do yourself to learn anything trustworthy.

What a hair sample can and cannot physically show

The hair you post to us is dead. The living part of hair is the follicle beneath the scalp; once the shaft has grown out, it is keratin — a structural protein, no longer metabolically active, with no blood supply, no immune activity and no ongoing chemistry connected to your digestion.

Hair analysis does have legitimate laboratory uses. Because the shaft grows steadily and locks in some substances that circulate in the blood while it is forming, hair can be used to look at exposure to certain drugs or heavy metals over a period of months. That is a real mechanism: a substance was in the bloodstream, and traces of it were deposited into the growing shaft.

Food intolerance is not that kind of thing. An intolerance is a difficulty processing a food — typically involving enzymes, gut transit, fermentation or the way your body handles particular compounds. None of those processes deposit a food-specific marker into a strand of hair, and no published work establishes that they do. So the honest description of what our lab does is this: it uses your sample in a proprietary, non-diagnostic bioresonance process to generate a reference list at a defined threshold. That list does not measure bodily reactions or establish an intolerance. That list is an output of a screening device. It is not a measurement of your digestive system, your enzymes, your gut bacteria, your antibodies or your immune response, and it should not be read as one.

So why do people still find it useful?

Because of a practical problem the evidence does not solve for you.

If you suspect food is involved in how you feel, the recommended approach is elimination and reintroduction. But an ordinary adult diet contains several hundred distinct ingredients across a week, and food reactions can be delayed by hours — which means working backwards by memory across three meals and a dozen ingredients rarely lands anywhere. Faced with that, most people do one of three things: cut out one obvious food, notice nothing, and give up; cut out a large group of foods at once, feel something change, and never find out which part mattered; or do nothing at all, for years.

A shortlist changes the shape of the task. Instead of “which of several hundred things?”, you have a defined set of items to remove for six weeks and reintroduce one at a time. That is a task with a beginning and an end. It is not a more accurate task — the shortlist did not come from a validated method — but it is a tractable one, and a tractable plan that gets finished teaches you more than a perfect plan you never start.

This is the whole honest proposition. You are buying a structured starting point and a framework for self-observation, at £49 for the Gold screen, £65 for Platinum, £37 for Silver, £74 for a couples pair or £125 for a family set, with an optional personalised meal plan at £10 to make the six weeks easier to actually eat through. What you are not buying is a verdict about your body.

We have been trading since 2017 and are rated 4.0/5 on Google. The rating describes customer experience; it is not evidence that the reference service measures bodily reactions or works as a diagnostic test.

Does this sound like you?

• You have suspected food is involved for months or years, but every attempt to work it out has fizzled out within a fortnight
• You have already cut out one obvious food, noticed nothing definite, and are not sure what to try next
• You have seen your GP, serious causes have been considered, and you have been left to work out the food side yourself
• You need somewhere sensible to start rather than a diagnosis — and you understand those are different things
• You are willing to run six weeks properly and write things down, because you know that is where any answer comes from
• You would rather be told the method is unvalidated up front than discover it afterwards

If most of those are true, a shortlist is likely to be worth £49 to you. If what you actually want is a definitive answer about a specific symptom, no hair screen will give you that, and we would rather say so now than take your money.

How to run a focused six-week elimination

The report is the smaller half of this. The elimination is the part that generates evidence about you, so run it as an experiment rather than a diet.

1. Start the diary before you change anything. Spend one week eating normally and recording what you eat and how you feel — digestion, energy, sleep, comfort — on a simple daily scale. Without a baseline you cannot tell whether anything changed.
2. Take the top items only. Pick the small number of items flagged as worth exploring first. Removing twenty foods at once makes the six weeks miserable and the result uninterpretable.
3. Remove them completely for six weeks. Partial removal is the most common reason people end up with no clear signal. Check labels; several flagged items hide inside processed foods under other names.
4. Keep everything else stable. Do not start a new supplement, a new exercise programme and a new sleep routine in the same fortnight. One variable at a time is the entire point.
5. Reintroduce one item at a time. After the six weeks, bring back a single item in a normal portion, then wait three to five days before the next one, still recording. Reactions can be delayed, which is exactly why the gap matters.
6. Repeat anything that looks interesting. If an item seems to matter, remove it again and reintroduce it a second time. A pattern that repeats twice is worth something. A pattern that appears once could be the week you had.
7. Write your own conclusions, not the report’s. At the end you should have a short list of items that consistently coincided with how you felt, and a longer list the report flagged that made no difference at all. Both are useful. The second list is not the screen failing — it is the process doing its job.

If the diet is becoming narrow, stressful or difficult to sustain, stop and speak to a GP or a registered dietitian. Long-term restriction has its own costs, and no shortlist is worth an unbalanced diet.

The 90-day money-back guarantee

Given everything above, the reasonable question is why you would risk £49 on an unvalidated method at all. The guarantee is our answer to that, and its conditions are the point rather than the small print.

Follow your plan for at least six weeks, keep a simple food diary while you do it, and if you are no better off, email us within 90 working days and we will refund you in full. The conditions exist because the six weeks are where any change would come from — the report only tells you where to start. Asking for the diary is not an obstacle course; it is the only way either of us can tell what actually happened.

What that arrangement means in practice: the cost of finding out is your time and attention, not your money. We keep your records for six months, so a resend or a query inside that window is straightforward. If you run the plan properly and nothing improves, you have lost nothing financially, and you have learned that those particular items were not the story — which is genuinely worth knowing.

Common questions

Straight answer — does it work?

Not as a diagnostic test, no. There is no robust evidence that hair screening can identify which foods you are intolerant to, and no UK health body endorses it. It works as a shortlist generator: it gives you a defined set of items to test on yourself through elimination and reintroduction. Whether that is worth £49 depends on whether a starting point is what you are missing.

If it is not validated, why sell it?

Because the practical problem is real even though the test is not diagnostic. People need a place to begin, and a structured plan they finish beats an unstructured one they abandon. We sell it on that basis, we say so on every page, and we refund people who follow the plan and get nothing from it. What we will not do is describe it as something it is not.

Would a second sample give the same results?

Not necessarily. Repeat testing of this kind has been reported to produce differing item lists from the same person, and we would rather you heard that from us. It is one more reason to treat the report as a prompt for exploration and to trust your six-week findings over the printout.

Will the report tell me what is causing my symptoms?

No. It lists entries generated by the proprietary, non-diagnostic process; it does not establish cause, and it does not test for any medical condition. If you have persistent symptoms you want explained, that is a conversation for your GP, who can consider causes a hair screen has no view of at all.

Is this an allergy or coeliac test?

No to both. Allergy is assessed with specific IgE blood tests, skin-prick testing or a supervised challenge; coeliac disease requires specific blood tests and confirmation arranged through your GP, and you should not remove gluten before that testing because doing so can affect the results. If you suspect either, see your GP rather than ordering a screen.

Can I test a child?

We screen from age 6 upwards. In practice, we would encourage you to involve your GP or a paediatric dietitian before restricting a child’s diet at all — growing children have less room for a narrowed diet than adults do, and a shortlist is not a reason to skip that conversation.

What do I actually send you?

Nine or ten strands of hair, a few centimetres long, snipped from the crown or nape. There is no kit to wait for: after you order we email the instructions, and you post the strands to our UK lab yourself in an ordinary envelope. Your report follows within 3 working days of the sample arriving.

Related reading

• How hair testing works
• How to test for food intolerance
• Food intolerance vs allergy

More: Food Intolerance Guides