It’s quite fashionable nowadays. The internet is full of stories of how everyone from movie stars to everyday people have shed stubborn pounds on the ketogenic diet. Some suggest that this type of diet may also be helpful in managing diabetes and preventing Alzheimer’s disease. So is it a miracle diet or just the latest fad?
How does the keto diet work?
The ketogenic diet is a type of high-fat, moderate-protein, low-carbohydrate diet that differs from general healthy eating recommendations. Many nutrient-dense foods are sources of carbohydrates, such as fruits, vegetables, whole grains, milk, and yogurt. In a ketogenic diet, carbohydrates from all sources are severely restricted. To keep carbs under 50 grams per day, keto dieters often don’t eat bread, grains, or cereals. And even fruits and vegetables are limited because they also contain carbohydrates. For most people, the ketogenic diet requires major changes in the way they normally eat.
Why Does the Keto Diet Restrict Carbohydrates?
Carbohydrates are the main source of energy for our body. Without enough carbohydrates for energy, the body breaks down fat into ketones. Ketones then become the main source of fuel for the body. Ketones provide energy for the heart, kidneys and other muscles. The body also uses ketones as an alternative source of energy for the brain. Hence the name of this food pattern.
For our bodies, a ketogenic diet is actually a partial fast. During a state of total fasting or starvation, the body has no source of energy. Therefore, it breaks down lean muscle mass for fuel. With the ketogenic diet, ketones provide an alternative source of energy. Unlike a complete fast, the ketogenic diet helps maintain lean muscle mass.
Is the Keto Diet Safe?
This type of diet is not recommended for people with:
- thyroid problems
- liver diseases
- gallbladder disease
- pancreatic disease
- eating disorders or history of eating disorders
Additionally, there are short-term and long-term health risks for everyone associated with the ketogenic diet. Short-term health risks include flu-like symptoms. For example, upset stomach, headache, fatigue and dizziness. This is called the “keto flu.” Some people also report trouble sleeping. Reducing your intake of fiber-rich vegetables, fruits and whole grains can also increase your risk of constipation. People on the ketogenic diet often need to take a fiber supplement to maintain the rule, but this should be discussed with a healthcare provider.
Long-term health risks of the keto diet include kidney stones, liver disease, and vitamin and mineral deficiencies. To limit carbs, many nutrient-dense fruits and vegetables are cut out. Therefore, the intake of vitamin A, C, K and folic acid is usually low.
What about the science?
The ketogenic diet has been used to help control epilepsy, a disorder characterized by seizures, for more than 100 years. More recent studies are evaluating the ketogenic diet as an alternative dietary treatment for obesity and diabetes. Research results on the benefits of the ketogenic diet for these health conditions are extremely limited. Studies on the effectiveness of the ketogenic diet have been done with small groups of people. And, most Alzheimer’s research is based on research done on laboratory animals. More research is needed to fully assess the safety of this type of diet. Additionally, studies need to be done on the long-term health effects of the ketogenic diet.
The high-fat nature of the ketogenic diet is highly controversial. A large body of research has shown that diets high in saturated fat can increase the risk of heart disease and other chronic health problems. The risk that people on a ketogenic diet may take to their long-term cardiovascular health has not been fully studied.
Body mass index and individual metabolic rates affect how quickly different individuals produce ketones. This means that on the ketogenic diet, some people lose weight more slowly than others.