Giancarlo Caldesi has given up two of his favourite foods - sugar and wheat - to stay healthy. Before Coeliac Awareness Week begins on Monday, Kate Whiting joins the chef and his wife Kate for a masterclass in gluten-free gourmet 

From your first spoonful of cereal at breakfast, to that lunchtime sandwich and cupcake teatime treat, much of what we eat every day contains wheat, and with it, the protein that forms gluten.

Now imagine you were Italian and you'd grown up eating pasta and pizza. You'd trained as a chef to cook the meals you love and then one day, you're diagnosed with coeliac disease and have to stop eating them altogether.

This is exactly what happened to 63-year-old Giancarlo Caldesi, who runs two restaurants and a cookery school with his British wife Katie, and who also has type 2 diabetes.

"I close my eyes and think of original pizza in Naples - best pizza ever - and it makes me want to sit down and cry," admits the father of two boys, when we meet in London cookery school La Cucina Caldesi.

Just the day before, after a three-year struggle with "debilitating" symptoms, he'd finally had the official diagnosis from his doctor following positive blood test results. Caused by the immune system reacting to gluten, coeliac disease affects one in 100 people, with symptoms including bloating, diarrhoea, constipation, tiredness, mouth ulcers, sudden weight loss, hair loss and anaemia.

The only treatment is to entirely cut out gluten from the diet, which includes cutting wheat, barley and rye, in order to manage symptoms and avoid serious long-term complications.

His own experiences have spurred Giancarlo and his wife on to create a 'New Food, New You' cookery course, to show people that it is possible to cook gluten (and sugar) free meals that are still tasty and satisfying.

While Katie does most of the teaching, Giancarlo pops in from the restaurant to make sweet fresh almond milk from whole nuts in his special Kuvings machine. His arthritis is playing up today after a long flight back from Vietnam, but he's still able to shake hands, something he couldn't do when he was eating gluten.

"One of the major problems with any disease is that you think everything is normal. You eat something and then you have to run to the loo, you think that's normal. You tend to find excuses for yourself all the time and you don't find the truth of what is really wrong," he says.

"It's like the engine of a Ferrari, where you get that clean beautiful sound and then you put some sugar or gluten into it, some ghastly stuff, and suddenly that beautiful sound is gone and you know something is not right.

"When you eat the wheat, it makes you feel very sleepy, also your intestines are no good, you rush to the toilet - it's very debilitating, because you have to think of quick exits. You feel foggy and fuzzy and my arthritis was getting stronger and stronger."

Together, Giancarlo and his artist wife, who met in 1997 when she came to paint a mural at his first restaurant, devised a menu that is tasty and wholesome, filling but not draining.

Over a buzzy four hours, we make 10 recipes, some from ancient Rome, such as Lagana Seeded Wine Crackers with gluten-free ground flaxseeds and buckwheat flour, a delicious cake with no sugar or gluten, with the very tempting sounding title Black Bean and Sweet Potato Chocolate Mud Cake - and my personal highlights, Sweet Potato and Buckwheat Pizza and Courgetti.

The latter, 'spaghetti' made from courgettes, is something of a revelation. Very quick and fun to make, using a spiralizer which shreds the courgette into curly strips, it tastes like a healthier version of the real thing. Katie tells me her 12 and 14-year-old boys don't even notice the difference, as long as she peels the courgette first to disguise the green.

On this new diet, Giancarlo has lost 11 kilos and feels like a new man: "From the top of my head, three quarters of my body is feeling completely different, liberated actually, full of life. I can rationally think straight and faster, and the magical thing is it's lasting.

"And also now, if I eat something wrong, I know immediately because of the pain. And I don't eat those things, because I have decided to be well is worth more."