I have signed up for a charity trek in Brazil, which takes place in October this year. It's a gruelling 10 day challenge through the jungle, covering 180 miles, which includes cycling and canoeing as well as many, many miles of hiking. I'm 45 and I've never participated in anything like this before, but I've got plenty of time to train and I've enlisted the advice of a personal trainer. The charity is also providing information and support. However, I know it's going to put my body under a lot of pressure. Aside from getting fit, what else can I do to prepare for this kind of effort? Are there any supplements I should be taking?

In terms of preparation, getting your gut really healthy is at the top of the list. Ensuring that levels of good bacteria are high will make you less susceptible to bacteria and parasites that cause traveller’s diarrhoea, as well as raising overall immunity and helping to protect against fungal and yeast infections that tend to thrive in hot, steamy jungle conditions. For some reason mosquitoes seem to be particularly attracted to anyone with constipation, so it is also wise to try and address any irregularity beforehand.

Try to include plenty of fibre-rich vegetables and wholegrains in the diet, plus natural live yoghurt and onions, leeks, garlic and bananas, all of which help boost beneficial gut bacteria and encourage regularity. Try a mid-strength probiotic such as Biocare’s Bioacidophilus Forte for 2-3 months before you go, switching to Biocare’s Travelguard once you are there which contains added protection against bugs and parasites.

To help increase strength and endurance Spirulina can be very helpful. This blue-green algae is the only plant source of glycogen, the body’s main immediate and long-term energy source. During intense or sustained exercise glycogen helps to increase energy reserves and muscle functioning. Try taking 10 capsules of Synergy Organic Spirulina 30mins before training and on the trek before setting out each day, available from xynergy.co.uk tel 08456 585858. B vitamins also help sustain energy levels under stressful conditions – and B1 is said to help repel mosquitoes! Try Biocare’s B-Complex.

It’s important to take care of all scratches, cuts and blisters as these can develop into tropical ulcers if left untreated – try Kiwiherb’s antifungal and antibacterial Manuka Paint that is easily applied on the go. For a natural, DEET free bug repellent, try Neem Herbal Outdoor Spray, especially formulated for use against mosquitoes in the notorious Florida Everglades, both available from xynergy.co.uk tel 08456 585858.

Stella New RSHom MBANT is a registered homeopath and nutritional therapist with clinics in Midhurst and Farnham, and technical consultant for Xynergy Health Products. 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