If you’ve been following a carb-free diet in the hope of shedding some extra kilos, you may be unwittingly putting your health at risk.
Food fads that replace carbohydrates with protein and fat, such as the ketogenic (keto) or paleo diets, have gained popularity in recent years, but according to food scientist Dr Vincent Candrawinata many people across the country could be facing serious kidney issues due to their eating habits.
The keto diet requires people to cut out foods such as bread, rice, potato and sugar-based products such as soft drinks, cakes, lollies and biscuits and instead load up on protein-rich, high-fat foods such as meat, dairy and oils. The idea is that the body uses fat as its biggest source of fuel, breaking it down into ketones in a process known as ketosis.
While the popular paleo diet encourages its loyal followers to cut out grains, legumes, refined sugars and dairy and eat plenty of meat, seafood, nuts and starchy vegetables.
However, Candrawinata says the increased portions of protein in the diet results in higher levels of ketones, which is linked to kidney failure.
“For most healthy people a high-protein diet generally isn’t harmful, particularly when followed for a short time, however studies have confirmed that there are significant risks of [following] a high-protein diet with carbohydrate restriction for the longer term,” he says. “Those with existing kidney issues are at higher risk.”
Carbohydrates are the body’s main source of energy. In their absence, your body will use protein and fat for energy. However, when the body begins to burn fat, it also begins to burn the muscle tissue as well.
“Once your body begins to burn large amounts of body fat, compounds called ketones are accumulated in the body,” he explains.
A high-protein diet can also result in nutritional deficiencies due to a lack of fibre, “which can cause problems such as bad breath, headaches and constipation”.
Candrawinata says there are much healthier ways to lose weight that won’t cause other problems in the long run. He recommends eating a balanced diet made up of ‘good’ carbohydrates such as whole grains, legumes and nuts, adding fish, chicken and lean meats into your diet, drinking more water and exercising regularly.
Many health experts in the past have also criticised low-carb diets and labelled them dangerous fads. A recent study, published in Lancet Public Health journal, found those with low-carb diets died an average of four years earlier than those with moderate intakes of carbohydrates.