Is a high protein low carb diet the answer to our prayers?


People naturally love a one size fits all approach, it’s in our nature. But, as with most nutrition related subjects the ‘very low carb, high protein approach’ just isn’t as simple as it sounds. We are often confused about what constitutes a carb. Similarly we are often misinformed about the type of carbs that are recommended, consequently carbs in general have been given a bad name. On the other hand protein has been endorsed as being the new saving grace, but again there are caveats to this that seem to be ignored.

First we must define what we mean when we refer to carbohydrates and when we refer to proteins. Carbohydrates are found in many different foods including fruits, vegetables, milk and beans, not just in bread, cookies, pasta, soft drinks and pastries. Additionally carbohydrates like bread, and pasta vary in their nutritional value according to whether they are made up of wholegrains or refined grains. Since carbs are almost everywhere, Foods containing carbohydrates are an important part of a healthy diet but it is important to choose nutrient rich carbohydrates that also provide vitamins, minerals and fibre, not just energy. Similarly proteins are an essential part of a healthy diet but the type of protein chosen is crucial. Some foods can be very high in protein but extremely high in saturated fat and salt, whilst others can be really nutritious.

To simply recommend a low carbohydrate high protein diet is too vague and if interpreted incorrectly could be harmful. If someone were to adopt a truly low carbohydrate diet they would struggle to consume essential vitamins, minerals and fibre from fruits, vegetables and wholegrains. Similarly if someone were to only focus on the protein content of their diet it is likely they would over consume in red and processed meats and consequently salt and saturated fat.

We must also remember that it is  impossible to observe one nutrient in isolation, we must understand how changes influence the diet as a whole. If someone is reducing their carbohydrate intake, their calorie intake will fall as a result. Often this is compensated with more fat and protein and vice versa. As a result it is not just that nutrients we are then measuring, it is the relationship.

“A low-carbohydrate diet that limits the intake of fruits, vegetables, and legumes cannot be endorsed,” (Harvard school of public health)

While there is evidence to suggest that restricting refined carbohydrates and promoting lean meat and vegetarian sources of protein can be beneficial to a person’s risk of disease, many people take this too far without understanding the consequences. Very high protein diets can lead to kidney problems in vulnerable people, and research shows it could increase risk of colonic disease.

Finally, although research is showing that low-carbohydrate may be superior to low-fat diets for weight loss in the very short term, there is little evidence to suggest this is the case after a period of about six months. It is clear that we need a lot more long term research in this area.

It may be a boring message, and not the quick teatox or cleanse that many want, but most of us in the western world simply need to increase the number of fruits, vegetables, wholegrains, and vegetarian sources of protein like nuts, seeds, and beans in our diets, and try to reduce the amounts of salt, sugar and saturated fat. Balance and variety is the key to a healthy diet, not overly simplistic diets.