What You Need to Know About the Ketogenic Diet
The ketogenic diet is very trendy lately. It is a diet extremely low in carbs and very high in fat. After 24 to 36 hours, glycogen stores in the liver and muscles are depleted, insulin secretion decreases, and ketone bodies formation (ketogenesis) becomes the only option to feed the brain.
What is the ketogenic diet?
To achieve this ketogenic effect, carbohydrate intake must be between 20g and 50g per day, mostly from low carbohydrate vegetables. In comparison, a regular diet contains about 175g to 250g of carbohydrates per day. With the ketogenic diet, it is not possible to eat starchy foods or fruits. Fat intake is approximately 75 to 80% of total calories, and protein intake is moderate. The adaptation to ketogenesis is responsible for the side effects often experienced at the beginning of this diet, such as fatigue, nausea, dizziness, headache, difficulty sleeping, constipation, ketosis breath and episodes of hypoglycemia.
The possible benefits of the ketogenic diet
This diet has been known for decades to be successful for the treatment of epilepsy in children. Recently, people started trying it to treat all kinds of other conditions. Some recent short-term studies suggest that this diet may promote weight loss, increase resting energy expenditure, decrease appetite or cravings, increase satiety, lower blood pressure, and improve diabetes control as well as the lipid profile (decrease triglycerides and increase good HDL cholesterol). However, it must be understood that these are preliminary studies and that other longer-term studies are underway to better evaluate these effects. Meanwhile, current scientific evidence does not support this diet except to treat epilepsy.
The dangers and potential risks of the ketogenic diet
- It has been associated with an increase in LDL cholesterol, which has a negative impact on heart health. Favoring good fats could perhaps counter this effect.
- It can create nutritional deficiencies, including B vitamins, beta carotene and vitamin C (largely found in fruits, vegetables, whole grains and legumes) as well as calcium. The contribution of several phytochemical compounds with antioxidant properties is also very limited. It has been shown that beta carotene, vitamin C and polyphenols found in phytochemicals, thanks to their antioxidant properties, exert a protective effect against various pathologies including cardiovascular disease and cancer.
- The fiber intake in this diet is often below recommendations, which can increase the risk of colon cancer and affect the gut microbiota. A balanced intestinal microbiota is important for health. A diet low in fiber and carbohydrates and high in fat and animal protein is associated with a reduction in microbiota diversity. It is also associated with a reduction of the good bacteria that produce short-chain fatty acids which are beneficial for health (including for the immune system) and an increase in the bad bacteria associated with obesity, inflammation and chronic disease.
- The long-term effects of the ketogenic diet are not known. This diet is characterized by weak long-term adherence. Thus, if people do not follow the plan in the long term and return to their old ways, they risk putting back on the weight that they lost and often even more.
- The ketogenic diet has the effect of acidifying the body, which can lead to the loss of bone calcium, and, therefore, a demineralization of bone tissue and increased risk of osteoporosis. This state of ketoacidosis can also lead to the development of kidney stones. This diet can also be dangerous for those who have diseases such as diabetes and hypertension and who take medication, since the dose of the medication must be adjusted along the way according to changes in their biochemical parameters.
To be followed only under medical supervision
Because of the potential risks associated with the ketogenic diet, close supervision by healthcare professionals (Physician, Registered Dietitian) is necessary for people who follow this diet. To ease its adoption, SOSCuisine will soon launch a ketogenic meal plan, available under medical supervision.
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