With a low-carb diet, you eat less carbohydrates than recommended. Some low-carb diets aim to improve blood sugar levels. Others are designed to lose weight or are based on the idea that it would be healthier to avoid certain products that contain carbohydrates.
There are advantages and disadvantages to a low-carb diet. One advantage is that these diets are usually high in protein, and eating enough protein during weight loss can help maintain muscle mass. A disadvantage is that many low-carb diets tend to provide a lot of (saturated) fat and very little fiber.
A low-carbohydrate diet, or «low-carb, high-fat diet,» is a diet that gets relatively high energy from protein and fat and low energy from carbohydrates. A low-carb diet provides 50 to a maximum of 130 grams of carbohydrates per day. We speak of a ketogenic diet if you take a maximum of 50 grams of carbohydrates per day, which is extremely low.
One comparison: the average adult woman eats about 225 grams of carbohydrates per day. This is a normal amount. The Health Council of the Netherlands advises that those who want to eat healthy get 40-70% of their energy from carbohydrates. For the average adult woman this equates to about 200 to 350 grams per day.
What is the purpose of a low-carb diet?
Some low-carb diets aim to improve blood sugar levels. For people with type 2 diabetes, such a diet under the supervision of a dietitian may be helpful. A low-carb diet can cause people to lose weight if they consume fewer calories than before the diet. Losing weight has a positive effect on the insulin sensitivity of overweight diabetics.
Many low-carb diets are designed to help people lose weight. The best known low-carb weight loss diets are Atkins, Dukan, and Dr. Frank. Other relatively low-carb diets are the Total Wellness Diet, the Mayo Diet, South Beach, Scarsdale, and the 17-day diet.
Then there are the low-carb diets based on the idea that it is healthier to avoid certain carbohydrate products. The Paleodiet is an example of this.
Can you lose weight on a low-carb diet?
Any type of diet where less energy is consumed than used will result in weight loss. This also applies to a low-carb diet where fewer calories are consumed than before. But if you eat the same amount of calories, a low-carb diet will not result in greater weight loss than a high-carb diet.
Low-carb diets do not cause more long-term weight loss than high-carb diets.
What are its benefits?
A low-carb diet is usually rich in protein. A low-carb, high-protein diet can give you a greater sense of satiety. So you will feel fuller for longer. Also, protein is important for building muscle. Eating enough protein during weight loss can help maintain more muscle mass.
What about the downside?
The disadvantages of a low-carb diet can be:
Low-carb diets are often also high in fat. High-fat diets are also often (too) high in saturated fat. Because of the risk of cardiovascular disease, the Dutch Health Council recommends replacing saturated fat products with unsaturated fat as far as possible. The guidelines of the Nutrition Centre are in line with this.
A low-carbohydrate diet increases the risk of deficiency of some nutrients, in particular certain B vitamins, dietary fibre and iodine. In addition, the positive health effects of some carbohydrate-rich products are lost. For example, whole-grain products reduce the risk of heart disease, type 2 diabetes and intestinal cancer.
Many people do not stick to a waste diet for long because it is too strict, too one-sided, or impractical. Also, weight loss is often not permanent because a healthy eating pattern has not been learned.
Ketogenic diet (very low-carb diet)
With a ketogenic diet, very few carbohydrates are eaten. That is, a maximum of 50 grams per day.
The carbohydrates you eat are converted into glucose in your body. Glucose gives your cells the energy they need, for example, to move and breathe. Glucose is stored as glycogen in the liver.
Normally, the liver gives glucose to the blood when the blood glucose level drops. But if you don’t eat enough glucose there is little glycogen stored in your liver and so this is not possible. This ensures that there is little glucose in the blood. The body realizes this and switches to burning fatty acids. When you burn fatty acids there are «ketones» or «ketone bodies». Ketones can be used by the brain, muscles and nervous system instead of glucose.
Ketones make the blood more acidic. The body has been following a ketogenic diet in «ketosis. Although in healthy people the body is able to maintain the acidity of the blood, not enough research has been done on the long-term health effects of ketosis.
The ketogenic diet is often even more difficult to maintain than a low-carbohydrate diet.
Low-carb diet for type 2 diabetes
A low-carb diet appears to have a positive effect on blood sugar levels in patients with type 2 diabetes in the short term. When weight is lost on such a diet, this weight loss also has beneficial effects on the body’s sensitivity to insulin and blood sugar levels. Weight loss is especially positive for overweight diabetics. More research is needed on the long-term effects of a low-carbohydrate diet on the health of people with type 2 diabetes.
If you have diabetes and want to follow a low-carb or ketogenic diet, good medical guidance and/or the guidance of a dietician is very important.
The ketogenic diet can be used in the treatment of epilepsy. In that case, it is always an adjunct to drug treatment. The diet can only be followed under medical supervision and is not effective for everyone. In the case of diseases such as multiple sclerosis (MS), there is currently not enough scientific evidence on the possible effects of the ketogenic diet.