In my experience working in the field of allergy and environmental medicine, Candida patients do far better only when they have modified their environments and not just their diets to reduce airborne moulds and humidity levels.

Many of my patients complain of a combination of joint pain, mood swings, obesity they can't shift, irritable bowel syndrome and bloating, food cravings and depression. Diagnostic dieting and a careful case history usually reveal a Candida overgrowth problem. This partially responds to changes in the diet, nutritional supplements and foods which discourage gut Candida. Nevertheless, on this regime, they never really get completely better. They also tend to yo-yo on and off the diet, not surprising as it is restrictive, boring and difficult to manage socially.

I have long suspected that what passes for a diagnosis of gut Candida overgrowth is probably more accurately termed a general gut 'dysbiosis', and it seems likely that a number of different organisms and yeasts can be responsible for this syndrome. I suspect that people with gut dysbiosis are also sensitive to inhaled moulds, which somehow trigger those in the gut and make people feel worse.

But, if efforts are made to reduce the total mould count in the home especially the bedroom and to avoid certain mould traps, my patients do appear to get over the problem and are able to return to a normal life and diet.

Air contains dust and mould spores, which are very small (less than five microns) and able to pass easily through filters. In my experience, almost all houses in England suffer from too high a mould count because of our damp climate. Luckily, though, it's not too difficult to dry out most indoor environments.

We have no instruments to measure mould count directly in air, although we know that mould count rises with the ambient humidity level. Inexpensive humidity metres are now available which can give an indication of mould count, but no information about individual moulds. Moulds sporulate (multiply) seasonally and are generally highest in summer. Ideally, the humidity should be kept below 35 per cent. Although some may find this too dry for comfort, it certainly lowers the overall mould count.

Central heating, low light heaters and dehumidifiers all help to dry the air. The latter should be plumbed in as they will wring out a lot of water from the air, and should be left on indefinitely. Although they are relatively expensive to run, they will really improve a bedroom.

Besides drying out your house, it's also important to avoid gardening and compost heaps, and even indoor houseplants. Initially, you should also refrain from mowing the lawn since cut grass contains a good deal of mould. In fact, it's a good idea to shut your windows when the grass is being mowed.

Organic food is good for your health in other ways, but it often has a higher mould count than the non organic variety as fungicides are not used.

The problem is compounded by old beds, pillows and mattresses, which trap dust and mould and are constantly breathed in while we sleep. Using a dustproof mattress and pillow covers, and washing the bedclothes frequently can cut down moulds considerably.

A typical patient of mine with this problem was Nora. She was 48 years old when she came to see me, complaining of a gradual onset over five years of weight gain, bloating and wind, water retention (ankle swelling), joint paints, mood swings and just feeling constantly tired. Dieting had signally failed to reduce her weight problem.

Nora had a responsible job in the armed services and was extremely capable. She'd had a hysterectomy eight years before I met her and had suffered a difficult infection which had required several courses of antibiotics.

She lived in a semidetached house with a garden near a river. She was a keen gardener and had noticed her symptoms were worse after mowing the grass, especially early in the season. She also had many indoor plants, which caused condensation on the insides of the windows.

When Nora first came to see me, she'd already been keeping a food diary, which included observations about the weather and how she felt on wet or damp days. This, together with a careful history, enabled us to diagnose a Candida problem following her operation and course of antibiotics.

Nora embarked on a basic anti Candida diet (see the WDDTY Guide to Candida and ME), avoiding sugar, yeast, most cheeses, anything fermented, wilted or visibly mouldy, and increasing her intake of olive oil and garlic. I suggested nutritional supplements, including probiotics.

But perhaps the most important part of her treatment was reducing the total load of mould in her life. This involved getting rid of houseplants, drying the air with dehumidifiers and making liberal use of central heating. I also suggested that she use low light heating in damp corners, have any obvious mould removed (by someone else) and avoid cutting the grass.

Gradually, Nora improved on this regime. After some weeks, she was able to broaden her diet. As her morning diarrhoea was cured, she was delighted to find that she could attend camp. Her mood and energy had returned to normal, her joints were better and she had lost some weight.

She still felt depressed in damp weather, but was able to cope now that she understood why.

!ADr Diana Samways