I've recently taken up running but I'm concerned that several of my toenails have turned greyish in colour. They also feel a bit sore. My trainers are comfortable and fit well, so I don't know what could be causing this. Could it be a fungal infection, and if so, how can I clear it?

This does sound like a fungal or yeast infection of the toenails, also known as tinea unguium. Initially the nails appear dull, grey or chalky, may be painful, and if left untreated will lift from the nail bed and eventually detach. Funguses and yeasts thrive in warm, damp conditions, so the combination of sports and ill-fitting trainers are a common cause. Other factors can include poor circulation, low immune status or systemic yeast infection, often triggered by an imbalance in the bowel bacteria.

In terms of diet, try to increase your intake of brightly coloured fruit and vegetables, particularly mixed summer berries which contain high levels of antioxidants and bioflavonoids, useful for boosting both circulation and immunity. Also increase natural live yoghurt to help boost beneficial bacteria, and garlic, a natural antifungal. Avoid alcohol, sugary foods and refined (white) carbohydrates as yeasts and funguses thrive on them.

In terms of topical treatment, Neem is one of the best natural antifungals. Try washing the area daily with Maximum Strength Neem Soap, then applying a drop or two of pure Neem Oil, one on the surface and one underneath the edge of the nail. Once you notice an improvement, continue this treatment for as long again to ensure best results.

Fungal infections can be stubborn, so it is wise to treat internally as well as topically. Try Biocare's Bioacidophilus Forte to help correct imbalanced gut flora, and either Neem Tincture or Higher Nature's Citricidal grapefruit seed extract, both natural antifungal agents. The homeopathic remedy Graphites may also help, although for best results seek treatment from a professional homeopath - see the Society of Homeopaths www.homeopathy-soh.org to find a homeopath near you.

Neem products are available from Xynergy Health Products www.xynergy.co.uk tel 08456 585858. Other supplements and homeopathic remedies are available from healthfood shops.

Stella New RSHom is a registered homeopath and dietary therapist based in West Sussex. Prior to her training she spent many years as an expedition leader, taking groups into some of the most challenging parts of the world, where she was inspired by the use of natural remedies for treating all manner of ailments. Email stella@stellanew.co.uk