"I've had a prickly rash for two months — what could it be?"

That is the question I very wisely Googled at 3am (piece of advice: don't do that!) when I'd been kept awake for another night with itchy arms.

It of course came up with all the classics — skin cancer, lymphoma, and some rare forms of all sorts. Google likes to catastrophise, and before long you can convince yourself of the worst case scenario whilst staring into the abyss that is your phone.

So rather than booking a plot at the local boneyard, I booked a doctor's appointment the next day (which is a mean feat within itself) and met with a lovely doctor who said: "The good news is it isn't skin cancer!" — phew. But she then went on to say: "We don't know what might have caused it. Have you changed your washing powder, soap? It might be the menopause" (gets blamed for most things these days) "or we could try a blood test just to be sure."

As I was putting on my coat, she flippantly asked: "Have you started taking any new supplements?"

I almost dismissed this question. I have always believed that what the body doesn't need it gets rid of — you know what assuming did.

I went home and thought about anything new I had started taking and realised I had started one called Neurobright in June — around the time the symptoms started. Nothing odd in this one, I thought. But when I cross-checked the other plethora of supplements I was taking, I realised I was taking a number of different ones containing the same types of vitamins.

Cue some more fervent Googling — this time at a more reasonable hour — and more specifically: "Are there any supplements or vitamins that cause prickly heat or rashes on sun-exposed areas if you take too much?"

Answer: Vitamin B6 makes your skin photosensitive and can cause persistent rashes on sun-exposed skin.

So I went back to my pill pot and checked. Well, what do you know — it turned out I was getting 2,500% NRV of B6 a day. FFS.

I did some more digging and what I found was alarming. Over-supplementing — taking more than the body needs — can be extremely harmful, even with nutrients that are otherwise beneficial in normal amounts. The risks depend on which vitamins are taken and how much.

And it is not just restricted to vitamins. I have now met three people who have had severe reactions to Turmeric, including nasty rashes — so it is worth looking into everything you are taking.

Fat-soluble vitamins (A, D, E, K) are stored in body fat and the liver, so excess amounts can accumulate and cause toxicity. Water-soluble vitamins (like C and B vitamins) are usually excreted, but very high doses can still cause adverse effects.

Some vitamins in excess can harm the liver, kidneys, or heart. High doses of certain supplements may also interfere with the absorption or function of others.

Contrary to popular belief, "more" is not always better. Some large-scale studies have linked excessive supplementation with increased mortality or higher cancer risk.

High doses of vitamins (like K or E) can alter blood clotting or interact with prescription drugs — including anticoagulants and chemotherapy.

• Food first. Most people get enough vitamins from a balanced diet. Supplements should fill gaps, not replace meals.
• Check labels. Many fortified foods already contain vitamins — adding pills on top can cause accidental overdosing.
• Talk to your doctor. Especially if you take multiple supplements or medications. Blood tests can determine whether you actually need supplementation.
• Stack carefully. If you take more than two or three supplements, cross-check the ingredients. Overlap is more common than you think.

At NeuroBalance, Amino Acid Therapy is one of the tools we use to support neurotransmitter balance — and this experience is exactly why we take a careful, targeted approach.

We do not recommend a blanket stack of supplements. We look at what is actually needed, in what dose, and from what source. As we say on our Science page: cheapest or most expensive are not always best. The right dose and the right quality matter — and we will always work with you to find options that suit both your needs and your budget.