Before starting a ketogenic diet or any other very restrictive diet, we strongly encourage you to consult your doctor or a member of your diabetes care team.
The ketogenic diet is arousing growing interest among people with type 2 diabetes because it would have benefits, among other things, on weight and glycemic control (blood sugar levels). It is however premature to recommend the adoption of the ketogenic diet to a diabetic person given the lack of knowledge on its medium and long effects term. Like other very restrictive diets, the ketogenic diet is difficult to maintain for more than a few months and can lead to overeating in response to deprivation.
What is the ketogenic diet?
The ketogenic diet, also called “very low carb diet” or “very low carb diet” contains mainly fats (lipids) and very few carbohydrates. According to studies, the carbohydrate content can vary between 20 and 50 g per day. This is the level from which we observe the production of ketones. For comparison, the diet currently recommended for people with diabetes (conventional diet) and presented in the form of a balanced plate provides between 130 and 225 g of carbohydrates per day! The conventional diet provides enough carbohydrates to meet the needs of the brain, estimated at 130 g per day.
To function throughout the day, the body needs energy from the food we eat. Carbohydrates are normally the main source of energy. In the ketogenic diet, lipids take over from glucose as fuel. The brain is the exception because a natural barrier blocks access to lipids. In the event of a severe restriction in carbohydrates, as in the ketogenic diet, the brain must therefore resort to an alternative source of energy called “ketone bodies”.
During the first days of a ketogenic diet, the body responds by drawing energy from the glucose stores stored in the liver and muscles. The use of these reserves releases a significant amount of water which is eliminated in the urine, causing a temporary and rapid weight loss due to dehydration. When glucose stores are depleted, the liver uses fats and proteins to provide energy to the body. The degradation of lipids by the liver generates ketone bodies which are primarily used to fuel the brain. Part of the ketone bodies is eliminated by breathing, which explains the “fruity” breath present in people who follow this diet.
In addition to this unpleasant breath, certain side effects usually occur during the first weeks following the start of the ketogenic diet. The most commonly reported are fatigue, headache, dizziness, nausea and muscle cramps. Hypoglycemia can also occur in some people with diabetes depending on their medication.1 Constipation sets in quickly and persists due to the lack of fiber. This problem is accentuated in the presence of insufficient hydration.
Effectiveness of the ketogenic diet
Many benefits are attributed to the ketogenic diet. However, several shortcomings in the studies reviewed limit the scope of the results obtained and make it difficult to evaluate this diet.
Here are the main weaknesses of these studies:
- Great variability, between studies, in the amount of carbohydrates in ketogenic diets tested; some diets qualified as ketones could provide up to 125 g of carbohydrates per day!
- Lack of consistency in the composition of the ketogenic diet in terms of the type of fat and protein to be consumed and the amount of vegetables.
- Some conventional diets tested did not comply with the recommendations and contained a significant proportion of refined starchy foods and foods with added sugar.
- Inability to verify whether participants actually maintained their adherence to the assigned diet (ketogenic or conventional) until the end of the study.
- Short-term studies, numerous biases, no distinction between diabetics and non-diabetics, absence of control group, small number of participants, etc.
What about the effects on weight when diets are not calorie restricted? Studies of type 2 diabetics with excess weight show that after 1 and 2 years, the ketogenic diet provides modest weight loss similar to that of the conventional diet. The decrease or loss of appetite that is associated with the presence of ketones in the blood does not seem to persist in the long term. It has also not been possible to demonstrate that the intensive use of fats in the ketogenic diet would be more effective in increasing basal metabolism than the conventional diet. In short, the ketogenic diet does not seem to be more effective in the long term for weight loss than the conventional diet.
Effects on blood sugar control
A decrease in A1C (gyrated hemoglobin) may be expected in a diabetic who follows a ketogenic diet because the amount of carbohydrates consumed is minimal. Over a period of 3 to 6 months, studies have shown a greater reduction in A1C with the ketogenic diet than with the conventional diet. However, this difference was no longer present after 1 year.
A decrease in anti-diabetic medication has also been observed in the short term with the ketogenic diet, but the long-term results are contradictory.
Long-term effects of the ketogenic diet
To date, the long-term effects of the ketogenic diet are still unknown since the duration of studies does not exceed 2 years. However, several researchers are concerned about its potentially harmful health impacts. The low consumption of certain foods such as fruits, vegetables and whole grain products whose recognized protective effects against certain cardiovascular diseases and cancer, could also lead to deficiencies in certain minerals, vitamins, and antioxidants in the medium term. In addition to chronic constipation, the lack of fiber in this diet could generate other negative effects on intestinal health by disrupting the micro biota (intestinal flora). This imbalance could therefore reduce the efficiency of the immune system.
Some precautions if you decide to follow a ketogenic diet
If you still decide to go on a ketogenic diet, here are some ways to lessen its potential unwanted side effects:
- Measure your blood sugar more often if you are at risk for hypoglycemia1;
- Take a multivitamin and dietary fiber supplements;
- Stay well hydrated with water throughout the day;
- Eat vegetables low in carbohydrates rather than eliminating vegetables completely (e.g. peppers, broccoli, lettuce, cucumber, etc.);
- Consume foods rich in calcium such as: firm cheeses, yogurt, almonds, etc.
- Choose good fats for heart health found in foods like olive and canola oil, nuts and oily fish.
Stay Healthier Note
In conclusion, unlike miracle diets, the conventional diet, represented by the balanced plate model, offers the diabetic person and those around him a varied diet, sustainable in the long term and where the pleasure of eating is at Appointment. Mediterranean or vegetarian diets are also interesting options. The choice of one or the other of these diets depends on the preferences of each since they have all demonstrated their beneficial effects on the health of people with type 2 diabetes. For complete details related to diabetes you can visit our site Stay Healthier.