What foods to avoid

ALCOHOL: It damages the mucus in our intestines, allowing unfriendly bacteria to dominate. CAFFEINE: It can raise stress hormones and sugar in the blood which impacts the gut. Try slowly cutting the week before you start the diet to avoid a caffeine withdrawal headache. SUGAR AND ARTIFICIAL

SWEETENERS: These can contribute to an imbalance of gut bacteria but sugar contained within whole fruit (not juiced) is fine. DAIRY: No cheese and milk, but live yoghurt is fine from week three. GRAINS: Wheat and rye contain gluten which can irritate the gut lining. Also avoid quinoa, rice and oats on the 30-day plan. BEANS AND PULSES: These contain substances called lectins which can irritate the gut lining, leading to unbalanced gut flora. Eat them again after the 30-day plan if they don’t cause you bloating.