It seems that every article about healthy eating and weight loss in magazines and newspapers currently recommends low carb or cutting out gluten. But what is the truth behind this and should everyone be eating a low carb or gluten free diet?
The simple answer is no. Carbohydrates are an important part of our diet. We may not have evolved eating grains, as the paleo diet points out, but for the vast majority of people, carbohydrates are our main source of energy and an important source of B vitamins and minerals. For hundreds of years we have been eating grains, however it is only in the past 30 years that a majority of the population has become overweight. There are probably two reasons for this: the introduction of processed, refined carbs (think of crisps, chips and breakfast cereals) and the widespread addition of sugar into everyday foods.
Refined carbohydrates and sugar have essentially the same effect on the body. They are broken down into basic glucose units and need little processing, so are absorbed quickly into the bloodstream. This is known as high GI (glycaemic index). Once in the bloodstream, they trigger the release of insulin which mops up the glucose and ushers it into the cells to be used to produce energy. If there is more glucose than the body needs, it is stored as fat. Lower GI foods, such as grainy breads, oats, brown rice, nuts and legumes are absorbed more slowly and don’t cause the huge release of insulin that can result in fat storage or the spike of energy followed by a crash.
Essentially we need to think of carbs less simplistically – low GI carbs provide long-lasting energy and nutrients. Refined carbs and added sugar are what we need to minimise or avoid.
So what about gluten? Gluten is a protein found in grains, such as wheat, that a very small minority (around 1%) of people are allergic to and causes a serious illness called coeliac disease. However, many people believe they are or could be gluten intolerant, which produces mainly digestive symptoms and fatigue. There is little scientific evidence to explain the huge increase in those claiming gluten intolerance in recent years. However, eating too much wheat, especially factory-produced bread, cakes and cereals makes many people feel sluggish and bloated. There is no need to resort to gluten-free products to address this. They generally don’t taste as good as the real thing! Reducing wheat and replacing it with oats or rice is a good idea. For example, substituting a wheat cereal for muesli made with oats or wheat crackers for rice cakes. Rye bread contains less wheat and sourdough bread is fermented for longer, making it more digestible.
For the vast majority of people, eating mostly low GI carbs, such as wholemeal pasta, brown rice, sweet potatoes, oats and bran and wholegrain bread is an essential part of a healthy diet. Even eating some higher GI carbs, such as mashed potato is not a problem when when included as part of a meal. It is the contents of the entire meal that ultimately determines how quickly the glucose enters the bloodstream and protein and fat slows its absorption.
However, for those who are overweight or conscious of maintaining their weight, it is worth looking at the amount of carbs you are eating. A good breakfast needs to include oats or wholegrain bread to provide energy for the day. However, at lunch and dinner, your plate should contain 50% vegetables, with 25% made up of meat or fish and 25% carbohydrates. Eating a low carb meal once a day can also help with weight loss as you’re eating less calories.