Aching joints and food: what a hair screen can and cannot tell you

This page is about aches and joint discomfort that people suspect might be linked to something they eat. It covers what people commonly report, which foods get trialled most often, how to run a fair six-week elimination with a structured reintroduction — and, just as importantly, when joint symptoms are not a job for a diet experiment at all. Joint pain is the topic on this site where we are most cautious, because some of the conditions that cause it are serious, treatable, and get worse if they are ignored while somebody quietly gives up tomatoes for two months.

What this screen is — and what it is not

What it is

• A hair sample screen that reports entries generated by the proprietary, non-diagnostic process across 700+ items on the Gold panel (350 foods and drinks plus 350 non-food items), for £49
• A shortlist — a way of choosing which handful of foods to trial first instead of guessing your way through your whole diet one item at a time
• A structure for a six-week elimination and a careful reintroduction, which is the part that actually teaches you anything
• Non-invasive and low effort: 9 or 10 strands of hair, posted by you in an ordinary envelope — no kit is supplied and none is needed
• Processed at a UK lab, with your report emailed within 3 working days of your sample arriving (allow 5–7 days from posting)
• Covered by a 90-day money-back guarantee, on the condition that you follow your plan for at least 6 weeks and keep a food diary

What it is not

• Not a test for arthritis, rheumatoid arthritis, osteoarthritis, psoriatic arthritis, gout, lupus or any other named condition. It does not screen for them, cannot rule them out, and must never be used instead of seeing a GP about them.
• Not a diagnostic test of any kind, and not an allergy test — it measures no antibodies, no inflammatory markers, no uric acid and nothing happening inside a joint
• Not proven. Hair-based screening has no proven accuracy for identifying food intolerance, and the same sample can produce different results on different occasions. The report on its own proves nothing about your body.
• Not a treatment. Nothing about the screen relieves, prevents or improves joint pain. If anything changes for you, it changes because of the dietary experiment you ran, not because of the report.
• Not a way of telling whether your aches relate to age, injury, activity levels, posture, weight, medication, an infection, or anything else non-dietary

Before you change anything: joint symptoms that need a doctor

Please read this section before the rest of the page. Joint pain has a long list of possible causes and several of them are conditions where early assessment genuinely matters. A food screen has nothing useful to say about any of them.

Book an appointment with your GP — and do not spend six weeks on an elimination diet first — if any of the following apply:

• A joint that is swollen, hot, red or tender to touch, particularly a single joint that has come on quickly
• Morning stiffness lasting more than about 30 minutes, or stiffness that eases only after a long period of moving about
• Joint pain that has persisted for several weeks, is getting worse, or is waking you at night
• Pain in several joints at once, especially if it is symmetrical (the same joints on both sides)
• Joint symptoms alongside fever, an unexplained rash, unintended weight loss, night sweats or profound fatigue
• A joint that gives way, locks, or cannot bear weight, or pain that followed an injury
• Any joint symptoms in a child, or in anyone taking medication that affects the immune system

None of that is a reason to panic; it is a reason to get looked at. Blood tests, imaging and a proper clinical examination can distinguish between causes that a food diary never will. If your GP has already assessed you and you are dealing with mild, grumbling, comes-and-goes aches with no red flags, then exploring diet is a reasonable thing to do alongside — never instead of — whatever your doctor has advised.

Why joints are the hardest symptom to pin on food

Joints fluctuate on their own

Aches wax and wane for reasons that have nothing to do with your dinner: how much you walked yesterday, how you slept, a cold coming on, a change in the weather, a new pair of shoes, a stressful week, or simply the natural cycle of whatever is going on in that joint. Many joint problems have naturally good spells and bad spells. If you remove a food during a bad spell, you will very often feel better a fortnight later — and the food had nothing to do with it. This is the single biggest reason people become convinced of a food link that does not hold up.

The delay problem

Where people do report a food link, it is usually described as delayed and vague rather than immediate and obvious: heavier, stiffer, more achy the day after a particular meal, rather than a sharp reaction within minutes. A delay of a day or more makes it almost impossible to identify the food by memory alone, because dozens of other things happened in between. That is exactly why a written diary and a one-food-at-a-time reintroduction matter far more here than in any other symptom on this site.

What the evidence actually says

We would rather lose a sale than mislead you. There is no robust scientific evidence that screening a hair sample can identify which foods cause symptoms, and no evidence that it can tell you anything about your joints. Hair is largely non-living keratin. Independent testing of this style of screening has found poor repeatability. We are not going to dress that up.

What the screen is genuinely useful for is narrower and more practical: it turns an overwhelming, open-ended question — “could it be something I eat?” — into a short, ordered list of items worth exploring first. Elimination diets fail far more often from being too broad and too vague than from picking the wrong starting food. A shortlist gives you a manageable experiment you can actually finish, and the experiment is the thing that produces the answer. If you want the best-evidenced route instead, ask your GP for a referral to a registered dietitian, who can supervise an elimination properly.

Foods people commonly report and trial

The list below is what people most often mention and most often try removing. It is not a list of foods that cause joint pain, and being on it does not mean a food is a problem for you. Treat it as the folklore and the starting points, not as findings.

Nightshades

Tomatoes, potatoes, peppers, chillies and aubergine are the classic self-experiment for aching joints. The idea circulates widely; the evidence for it is thin. Some people are convinced their aches settle without them, and the only honest way to find out whether you are one of them is to remove the whole group cleanly for six weeks and then bring them back one at a time. Watch for hidden sources: paprika and cayenne appear in a huge range of spice blends, and tomato turns up in sauces, soups and ready meals.

Gluten and wheat

Bread, pasta, cereals, barley, rye and a long tail of sauces, stock cubes and processed foods. If you are going to trial gluten, one thing must come first: coeliac disease is diagnosed by your GP through blood tests and sometimes a biopsy, and those tests only work while you are still eating gluten. Our screen does not test for coeliac disease and cannot exclude it. Cutting gluten out before being tested can make a coeliac diagnosis harder to reach, so speak to your GP before you remove it.

Dairy

Milk, cheese, cream, butter and yoghurt, plus the milk proteins hidden in baked goods, sauces and processed foods. Dairy is one of the most commonly trialled groups for almost every symptom, which is partly a reflection of how much of it most UK diets contain. If you remove it, take calcium into account — a dietitian or your GP can advise on that.

Alcohol

Frequently reported, and worth trialling for a straightforward reason: it is one of the few things on this list where people often notice a next-day difference. Bear in mind alcohol affects sleep, hydration and activity too, so a change after removing it does not necessarily point to anything food-specific. Alcohol also interacts with many medicines — if you take anything regularly, that is a conversation with your pharmacist or GP.

High-purine foods

Red meat, offal, some shellfish, and beer are the foods usually named in discussions of purines. We need to be careful here. Purine intake is discussed in relation to gout, which is a medical condition diagnosed and managed by a doctor, usually with a blood test and treatment that has nothing to do with a hair screen. Our screen does not test for gout, does not measure uric acid, and nothing on this page is guidance on managing it. If you have had a sudden, severely painful, hot and swollen joint — often a big toe, though not always — that is a same-week GP appointment, not a diet trial.

Ultra-processed foods, additives and sugar

Some people trial a general reduction in ultra-processed food rather than a single ingredient. It is a reasonable thing to try but a poor experiment: you change dozens of variables at once, usually eat more vegetables, often lose a little weight and frequently drink less alcohol, so if you feel better you will have no idea why. If you want an answer rather than a general improvement, change one thing at a time. The Platinum panel at £65 additionally covers preservatives, E-numbers and vitamin and mineral markers if that is the direction you want to explore.

Does this sound like you?

These questions are for people whose GP has already looked at their symptoms and found nothing needing treatment, and whose aches are mild and intermittent.

• Has your GP assessed your joints and found nothing that needs investigating or treating?
• Do your aches come and go, rather than being constant, worsening, or tied to one visibly swollen joint?
• Have you noticed you feel stiffer or heavier the day after certain meals, drinks or eating out — more than once?
• Have you already tried cutting something out at random, felt unsure whether it helped, and given up without a clear answer?
• Are you willing to keep a written daily diary for six weeks, rather than relying on memory?
• Would a shortlist of five or six things to trial first be more useful to you than an open-ended list of everything you eat?

If you answered no to the first question, start there. If you answered no to the fifth, the screen will not help you much — the diary is where the information comes from.

How to run a focused six-week elimination

The plan below is also what the 90-day money-back guarantee asks of you: six weeks of following your plan, with a food diary. To be plain about it, the guarantee is a promise about your money, not a promise about your joints.

1. Get cleared first. If any red flag in the section above applies, see your GP before starting. Do not delay a medical appointment to run a diet trial.
2. Set your baseline (days 1–7). Before removing anything, spend a week recording what you eat and scoring your joints each morning and evening from 1 to 10, plus how long any stiffness lasts. Without a baseline you cannot tell later whether anything actually changed.
3. Pick three to five items, no more. Take them from the top of your report. A shorter list you can genuinely stick to beats a long list you abandon in week two.
4. Weeks 1–2: remove them completely. Half measures produce unreadable results. Read labels — wheat, milk protein, paprika and tomato hide in a lot of things. Keep everything else about your life as steady as you can: same exercise, same sleep pattern, same medication.
5. Weeks 3–4: hold, and do not judge on single days. Joints have good days and bad days regardless of diet. Look at weekly averages in your diary, never at yesterday.
6. Weeks 5–6: finish the phase properly. By the end you should be able to compare a week of scores against your baseline week. If there is no difference at all, that is a real and useful result: food is probably not the lever here, and your time is better spent elsewhere.
7. Reintroduce one item at a time. Take a normal-sized portion of one removed food, on a day you are otherwise well, then keep everything else unchanged and score your joints for 72 hours. Joint responses, where people report them, are typically slower than digestive ones, so give it the full three days.
8. Leave 3–5 days between each new food, and if something seems to bring symptoms back, set it aside, wait a week, and repeat it once to confirm. A pattern that only happens once is not a pattern.
9. Write your own conclusions down. You should end with three groups: fine, unclear, and worth avoiding for now. Revisit the unclear group in a few months — and take any list of foods you plan to avoid long term to your GP or a registered dietitian, so your diet stays nutritionally sound.

What it costs

Suitable from age 6. Reports are available for six months; transaction records are retained separately under the privacy policy. We have been trading since 2017 and are rated 4.0/5 on Google.

Common questions

Can the screen tell me if I have arthritis?

No, and it is important to be blunt about this. The screen does not test for arthritis, rheumatoid arthritis, osteoarthritis, psoriatic arthritis, gout or any other condition, and a report full of green results does not mean your joints are healthy. Only a doctor can assess joint disease, using examination, blood tests and imaging. If that is the question you want answered, please book a GP appointment rather than a screen.

Will cutting out nightshades help my joints?

We cannot tell you that it will, and there is no good evidence that it does as a general rule. What we can say is that it is one of the most commonly self-trialled changes for aching joints, and that the only way to know whether it makes any difference for you specifically is to run a clean six-week removal followed by a proper reintroduction, with a written diary. Plenty of people run that trial and find no difference at all — which is a genuinely useful thing to learn, because it stops you restricting your diet for no reason.

My joints feel worse the day after a big meal out. Is that a food intolerance?

It might be a food pattern, or it might be several other things travelling together: alcohol, a later night, less sleep, more salt, more sitting, and a bigger portion than usual. That is precisely why one-food-at-a-time reintroduction exists. Change one variable, keep the rest constant, and see whether it repeats. If it only ever happens on evenings out and never when you eat the same food at home, the food is probably not the explanation.

How accurate is hair screening?

It has no proven accuracy. There is no robust scientific evidence that hair analysis identifies food intolerance, and repeat testing of the same sample does not reliably produce the same result. We publish that plainly because it is true and because you deserve to decide with it in front of you. What the report gives you is a starting shortlist rather than an answer, and everything you learn comes from the elimination and reintroduction you run afterwards.

Should I stop taking my medication or supplements during the elimination?

No. Never stop or change prescribed medication because of anything in a screening report or on this page. If a report flags something you take, or you are wondering whether a medicine is relevant to how you feel, that is a conversation with your GP or pharmacist. Also tell them if you plan to remove a major food group for six weeks, particularly if you are pregnant, breastfeeding, managing a long-term condition, or the plan is for a child.

How long does the whole process take?

Order, then follow the emailed instructions to snip 9 or 10 strands of hair and post them yourself — there is no kit to wait for. Your report is emailed within 3 working days of the sample reaching our UK lab, so allow roughly 5–7 days from posting. After that, the elimination itself is the long part: a baseline week, six weeks of removal, then several more weeks of reintroducing foods one at a time. Realistically you are looking at three months before you have a confident picture. Anyone promising you a faster answer about joints is not being straight with you.

Related reading

• How hair sample screening works — and its limits
• Food intolerance vs food allergy
• Trialling gluten: what to know first
• Alcohol and how people react to it
• Fatigue and tiredness

More: Food Intolerance Symptoms