There’s a lot of hype surrounding the ketogenic diet lately, and people have been using it for everything from weight loss to diabetes. Here’s the low down on this popular diet.
What exactly is a “keto” diet?
A true ketogenic diet is one that is very high in fat, low in protein, and very low in carbohydrates. It is typically comprised of about 80% fat, 15% protein and 5% carbohydrate. Ketogenic diets typically restrict carbs to less than 50 grams of carbohydrate per day, although the exact amount of carb restriction needed to enter ketosis varies depending on the person. Most people will see results with carb restriction in the 20-50 gram range.
The nuts and bolts:
Due to its high fat content, a ketogenic diet basically mimics “starvation” mode in the body since it cuts off our preferred energy supply from carbs and forces the body to tap into its fat stores and burn fat for energy, rather than stored carbohydrate found in our muscles, liver, and other organs. Glucose, or sugar, from carbohydrates is the body’s preferred energy source, and it will do anything it can to turn the nutrients we eat into sugar if stores are low. Even protein foods get turned into glucose if the body needs it. The glucose that we don’t either burn off or utilize for metabolic functions in our liver, brain, muscles, and other vital organs gets turned to fat. When the body does not get enough glucose, either from periods of starvation, or in this case, a carb-restricted ketogenic diet, it is forced to tap into its fat stores for energy and start burning ketone bodies.
Ketone bodies are acidic and change the pH of your blood. Thus, it takes the body some time to adjust to this new way of burning fuel. You may have heard this referred to as “keto-adaptation” or getting the “keto flu.” The keto flu is essentially your body getting used to burning ketones instead of glucose, and it can last anywhere from a few days to a few weeks. It is very important to stay hydrated during this process as elevated blood ketones can cause fatigue, headaches, difficulty concentrating, and dehydration. Typically, once the body adapts to a high fat, low carb and low protein diet, it will enter nutritional ketosis and stay relatively stable. To make sure you’re truly in ketosis, you can pick up urine ketone strips over the counter at any major drugstore.
I’ve heard that ketoacidosis is bad. What’s that all about?
Sometimes ketone bodies can lead to metabolic acidosis. This only occurs in individuals with diabetes whose bodies make very little insulin. This life-threatening condition is called ketoacidosis and will quickly lead to the emergency room. Ketoacidosis is metabolic derailment caused by lack of insulin, and it’s very different than nutritional ketosis. In nutritional ketosis resulting from a ketogenic diet, blood ketone levels will never be high enough to be dangerous. Although ketogenic diets can significantly improve blood sugar control in some diabetics (thanks to their low carb content), those who rely on insulin as their only source of medication should consult their healthcare provider before starting a ketogenic diet, as they will require close monitoring to ensure they reach nutritional ketosis, and not ketoacidosis.
All in all, here are the pros and cons:
Rapid initial weight loss is a notable benefit (but weight loss will likely plateau after a while)
Improvements in blood sugar control and potentially improvements in insulin resistance
Reduction in appetite due to the satiating factor of fat (it empties slower from the stomach)
Health in the long haul remains unknown in regards to ketogenic diets and heart disease, kidney health, liver disease, and insulin resistance. We definitely need more research in this area!
Perfectly healthy foods get the kibosh - fruits and certain types of vegetables are no-no’s on a keto diet. Thus, you’ll need to take a good quality multi vitamin supplement and make sure you’re consuming supporting nutrients to actually keep you in ketosis
Ketogenic diets are low in fiber (the diet eliminates most fruits, beans, legumes, all grains, and many vegetables), so you may need to take a fiber supplement
A high fat diet may be disrupt the delicate balance of healthy bacteria in the gut (known as the gut microbiome) because it lacks prebiotic-rich foods
Quality of life - ketogenic diets are incredibly restrictive and hard to follow
The final verdict:
A ketogenic diet can promote weight loss and be beneficial in the treatment of type 2 diabetes, but should be carefully planned to ensure adequate nutrient intakes and a good balance of healthy fats, especially if you have a history of heart disease. Too often, I see keto-crazed folks piling up on bacon, fried foods, mayonnaise, and the list goes on. A ketogenic diet can be done correctly (think avocados, nuts, fish, unsweetened full fat Greek yogurt, organic eggs, olive oil, and coconut oil).Typically, these types of very restrictive diets work best only in the most motivated individuals. Be cautious of diets that completely eliminate whole food groups. And remember – all foods fit in moderation.