The GP who gave up fruit and veg to cure her aches and pains

Clare Morrison noticed her muscle pains depended on her diet
New thinking: Clare Morrison noticed her muscle pains depended on her diet
A few years ago I started to feel unwell. My legs ached and tingled, I felt tired and my mood was flat. I slept badly — I suffered from restless legs and my muscles kept twitching — and couldn’t concentrate during the day.
My work as a GP involved having to learn how to use some different software and I just couldn’t get to grips with it at all — my mind was so befuddled. Although only in my early 40s, I stopped enjoying going out and couldn’t get enthused about seeing friends.
Initially, I put this down to depression, but then over the past two years or so I developed muscle pain and stiffness in my legs. In December 2010, I had great trouble climbing into the loft to get the Christmas tree, having neither the strength nor the enthusiasm for it.
Blood tests taken by a colleague were normal. But I worried about how I would cope with my work if things deteriorated any further. Having abandoned all unnecessary commitments, I longed to retire early, so I could stay in bed all day.
I diagnosed myself with fibromyalgia, a chronic, unexplained condition that can affect anyone, but is particularly common in women. It causes a range of symptoms, most notably disabling muscle pains.
It is generally incurable, and frequently causes a profound loss of function, with many sufferers having to give up work and normal activities.
Treatment includes painkillers, antidepressants, anti-epilepsy drugs, and cognitive behavioural therapy, although these rarely do more than improve the symptoms. Many doctors consider fibromyalgia a ‘heartsink’ condition — their heart sinks when a patient has it because it’s so hard to cure — so I didn’t consult my own GP.
Yet I did notice the muscle pains were worse after eating carrots, potatoes and parsnips. My son’s girlfriend made a delicious parsnip soup for a dinner party last year, and I enjoyed a big bowlful. The following day my legs were aching worse than ever, and I felt terrible.
So I decided to keep a food diary (something I sometimes suggest to patients) and worked out that I was also badly affected by potatoes, green beans, carrots, almonds and tomatoes. I searched the internet and found that, among many different theories, some suggested a link between fibromyalgia and dietary oxalate, though this isn’t recognised by the medical profession.

Oxalate can be thought of as a ‘natural pesticide’, an integral constituent of many plants, including root vegetables, stems, leaves, nuts and fruit. In fact, in some plants it forms the bulk of their dry weight.
Oxalate is very effective at deterring small insects and pests from damaging the plant, but even in large animals such as cows, horses and sheep it can cause problems if they ingest high-oxalate plants such as sorrel. Farmers and vets have noted that if animals are put in high-oxalate pasture, they can develop staggering, stiff legs, weakness, depression and diarrhoea. If they eat very large quantities, they can even die of kidney failure.
Oxalate poisoning is more likely if the diet is also deficient in calcium, as calcium binds with oxalate in the bowel, preventing it from being absorbed. It is known to be fatal in humans if you eat enough of it — 11 lb of rhubarb would kill you if you could stomach it.
More in desperation than expectation, I tried a low oxalate diet, cutting out virtually all ‘healthy’ food — I avoided most fruits and vegetables, salads, beans, nuts, wheatgerm, soya —  as well as tea, coffee and chocolate.
Clare struggled to get to grips with new computer software needed for her job as a GP (posed by model)
Mind strain: Clare struggled to get to grips with new computer software needed for her job as a GP (posed by model)
I could eat meat, fish, dairy, cheese, white rice, white pasta and only low-oxalate fruit and vegetables, such as bananas, peas, mushrooms, onions and cauliflower.  Within a few days the symptoms were totally gone; I could walk without pain and sleep normally. My motivation came back — in the eight months since starting the diet I’ve painted the house, landscaped the garden and booked a holiday.
Having suffered from the need to pass water frequently, my nocturnal trips to the bathroom have ceased. And, bizarrely, my teeth have felt clean all day long. I now realise that calcium oxalate (found in foods such as rhubarb and tea) leaves a recognisable grainy texture that stays until you brush your teeth.
Meanwhile, I’ve found eating any high-oxalate food results in tingling legs and muscle pains within a matter of hours. I’ve become so adept at noticing the signs I can tell what foods and drinks have oxalates in a short time after ingesting them.
I’m not an attention-seeking person — in fact, I am embarrassed by my dietary foibles; and I’m not looking for an excuse to avoid fruit and veg, as I’ve always enjoyed eating them. But cutting back hugely on my fruit and veg intake, and only eating from a small selection, has made me feel so well that I am determined to stick with my unusual diet.
Why did my apparent oxalate intolerance start in mid-life? Indeed, why is fibromyalgia so common in middle-aged women?
In truth, I’m not sure. In most people dietary oxalate passes through the bowel without being absorbed. Perhaps the bowel changes under the influence of falling oestrogen, allowing more oxalate to pass into the body. There it forms crystals, which are deposited in the muscles, brain and urinary system, to cause widespread symptoms.
It may also be that certain bacteria in the bowel normally break down the oxalate, but that these bacteria may disappear, perhaps after a course of antibiotics. There must be genetic factors, too, as fibromylagia is more common among families of those affected.
In my role as a GP, I have since seen several female patients in their 40s and 50s with similar complaints. Buoyed by my own response, I recruited five such patients to an unofficial ‘trial’ of a low oxalate diet.
Fruit and veg stall
Relief: Cutting fruit and vegetables from her diet has calmed Clare's symptoms
They had all presented with at least four of the following symptoms: muscle pain, tingly legs, fatigue, irritable mood, bladder irritation, poor concentration, restless legs and poor sleep.
I asked them to score the severity of these symptoms before and after changing to a low oxalate diet. They duly followed the complete opposite of all accepted dietary wisdom.
Out with bran-based cereals, nuts, spinach and smoothies, and in with Rice Krispies, sausages, shortbread and cola! I felt a bit of a quack for suggesting such an outrageous diet, but, after all, it had worked on me, so maybe . . .
To my delight, all the patients improved significantly — on average their symptom score halved after three weeks of the ‘unhealthy’ diet. Some may argue that this could be the placebo effect but, in my opinion, the results were too impressive and sustained for this to be the case.
As a GP of 17 years I’ve come across many patients convinced their alternative approach is beneficial — whether it’s homeopathy or herbal supplements — and my attitude has always been sceptical.
But ‘you are what you eat’, and we are increasingly finding associations between various foods and diseases, which were scoffed at in the past — a fact with which many of my medical colleagues would agree.
The fact that the cause of fibromyalgia is unknown and untreatable makes it imperative that we look at diet as a possible cause.
It is known that dietary oxalate can cause kidney stones.
As well as fibromyalgia, could dietary oxalates be responsible for other unexplained conditions, such as chronic fatigue syndrome (the symptoms of which overlap a good deal with fibromyalgia), irritable bowel syndrome, or restless leg syndrome?
I’m making no pretence of my ‘trial’ being any more than an unofficial (some might say anecdotal) analysis, but I’m really pleased that it helped my patients. The reason I’m writing this now is that I’m hoping it may help others, too.
Look up fibromyalgia on the Arthritis Research UK website and  when it comes to diet, it says: ‘No particular diet has been proven to help fibromyalgia, but we recommend keeping to a healthy weight by eating a balanced diet with plenty of fruit and vegetables.’
I would question the last sentence. Do we really need ‘five a day’? Do we dare challenge the sacred cow that fruit and veg are the panacea for all ills?
At the very least, if you are a rather fed-up middle-aged woman with a range of unexplained symptoms that seem to baffle your doctor, you might want to avoid following the usual advice to eat more fruit and veg.