"At restaurants, every meal had to be steak and salad."

London - Emma Houlton loves her food; whether it’s a Sunday roast with all the trimmings or an Italian meal, she’s always happy to tuck in.

But just five years ago, Emma, 29, would have baulked at eating pasta, bread, pizza dough and potatoes.

Why? Because, like thousands of others, she believed high-protein, low-carb regimes like the Atkins or Paleo diets were the most effective way to be slim.

But, after cutting down on carbs so much that she wouldn’t even eat dairy products as they contain lactose – a sugar – Emma believes she has permanently damaged her health.

“I was only a size eight but found it hard to stay slim,” she says. “Then, when I was 22, I saw a documentary about the Atkins diet, thought it was great and cut most carbs out of my diet.

“Breakfast was an omelette, lunch was chicken with lettuce and dinner was something meaty with vegetables like kale, cabbage, sprouts or runner beans, which don’t contain starch.

“I got all the classic symptoms associated with a low-carb diet: dry mouth, tiredness, crankiness and bad breath.”

But she saw great results – her 54kg weight was much easier to maintain.

Unbelievably, Emma, a creative director, stuck to the regime for three punishing years.

“At restaurants, every meal had to be steak and salad,” she says. “I’d go to a friend’s house for dinner and if they’d made pasta, I’d eat a tiny amount, so as not to be rude, and end up feeling really ill – with chronic bloating and having to dash to the toilet.

“I decided to come off the diet, and started eating normally, but the bloating became so bad I went to my GP. When he asked about my diet and I told him what I’d been doing, he pretty much rolled his eyes and said that in simple terms, my body had stopped producing the enzymes I needed to process carbohydrates.

“He said I’d have to reintroduce around one or two grams a week very slowly, and gave me peppermint oil capsules to relieve the symptoms. For weeks I had stomach aches, bloating and kept going to the toilet. It was embarrassing and painful.

“Although I’m better now, I have been diagnosed with irritable bowel syndrome. It only started during the low-carb regime. It’s effectively wrecked my health.”

Dr Sarah Brewer, author of Nutrition: A Beginners Guide, believes drastic no-carb diets like Emma’s can damage digestion.

“Bacteria in the bowel react very quickly to changes in the diet and the gut only has one way of complaining – through poor digestion,” she says. “It should recover but can take a while.

“It’s the quality of carbs you should focus on, not the quantity. Cutting out processed foods, such as white bread, cake and pastries is good for reducing the risk of diabetes, but carbohydrates shouldn’t be cut out all together. A healthy diet should consist of low-glycemic index carbs from foods such as healthy grains, fruit and lots of vegetables.”

Emma believes her diet had another damaging consequence. Soon after she came off it, she broke a bone in her foot while out running and believes being deficient in calcium for months may have left her bones vulnerable.

“The doctors suggested that the fact I hadn’t been drinking milk for over two years may have weakened my bones,” she says.

While low-carb diets have waned in popularity since a peak in the early 2000s, many still embark on them. Research shows nearly 50 percent of women sometimes feel guilty about eating carbohydrates and one in 10 always does. Such is the pressure to keep thin, many are willing to risk their health by cutting them out.

Mother-of-three Brooke Power, 27, suffered migraines and dizziness during 10 months on such a diet. She wanted to shed weight after the birth of her second daughter Zoe. Although she lost 20kg, she gave up when she realised it had affected her fertility.

“The only carbs I’d eat all day were the 50g of porridge made with water for breakfast,” says Brooke. “After that, it would be chicken salad, protein shakes or egg whites.”

She was losing 1kg a week. “I loved the results, but I was crying all the time because I was so hungry – but the more I did it, the more obsessed I was about leaving carbs out of my diet. The headaches and exhaustion were terrible. I’d feel dizzy and almost passed out several times. My hair became thinner. My periods stopped then became erratic. I put it down to the diet.”

Brooke’s rapid weight loss on the no-carb diet was to blame, says Dr Sarah Brewer.

“If you lose 5 to 10 percent of your body weight very quickly – as she did – the body reacts by shutting down ovulation because it knows it won’t be able to cope in a pregnancy. As soon as you start eating a well-balanced diet again, and regain weight, ovulation should begin again.”

Brooke conceived again almost immediately after reintroducing carbs.

Despite having learnt a hard lesson, she still sees carbohydrates as something of an enemy. “Even now I feel a bit guilty when I overdo it on carbs,” she says.

Dietitian Sioned Quirke says she often sees women in her clinical practice consumed with guilt.

“They think they’ve ruined their diet because they’ve eaten a slice of bread or a potato, but the reality is we need carbohydrates in our diet for energy and fibre to help our bowel function, as well as vitamin B. If you’re lacking vitamin B12, found in many fortified cereals, you can develop anaemia as it helps form red blood cells.

“Cutting out one food group is a sure way to become ill. Every cell needs glucose, so if you suddenly become depleted in it, you’ll begin to suffer lethargy, headaches, cramps, irritability, depression.

“You might have constipation, because of the lack of fibre. The bowel often doesn’t recover from a drastic change of diet.

“If you continue the regime for many months, the body starts to take its energy from protein stores in the muscles. So your muscles – including your heart – will be wasting away. Your skin, hair and nails will become thin, dry and flaky.

“I don’t think you’d survive for longer than about five years on an extremely low-carb diet.”

Gillian O’Toole, 32, who runs her own jewellery business, says she still feels guilty when carbs pass her lips, although ditching them has played havoc with her health. She took up the Paleo, or caveman, diet – based on the food supposedly eaten by Paleolithic humans.

Within three days of starting the Paleo diet – lots of meat, no sugar, carbs, caffeine or dairy – she had lost over 3kg, but felt so ill it felt like her body was in shock.

“I nearly passed out. I felt sick and couldn’t function properly. Around day three I developed a headache so bad I thought it was a migraine and my skin and scalp became dry and itchy.

“I started reintroducing things like sweet potato, but two weeks later noticed lumps in my armpit and was absolutely petrified it could be cancer.

“My GP reassured me it wasn’t cancer but tiny boils, and it was down to my unbalanced diet. I started eating carbs again and soon the lumps had gone.”

Dr Sarah Brewer says boils could result from an immune system weakened by rapid weight loss. “In those without diabetes, boils are usually associated with low immunity that promotes infection of hair follicles,” she says, and recommends vitamin supplements to dieters.

Gillian says her diet is back to normal now. “Even though the experience really scared me, I still feel guilty eating carbs. It’s ridiculous women are prepared to risk their health just to be slim, but we’re all as bad as each other.” – Daily Mail