You've heard of it but what exactly is a ketogenic diet? As promised in my prior post, “What’s a Ketone and Why Should You Care?” I will break this down to give you a working understanding. The prior post covers the benefits of a ketogenic diet and defines a ketone and ketosis.
The Anatomy of the Diet
A basic definition is that a ketogenic diet is one that allows your body to produce ketones to burn as fuel to encourage a state of ketosis. It’s helpful to establish for those who do not know, that calories in food come from the carbohydrate, protein and fat that make up that food. So now let’s start with three basic statements regarding the amount of carbohydrate, protein and fat that define a ketogenic diet.
- a ketogenic diet is not just a low carbohydrate diet
- a ketogenic diet is not a high protein diet but rather a moderate protein diet
- a ketogenic diet is a high fat diet
In order for a diet to be ketogenic a person must consume a low amount of carbohydrate. Estimates of what this amount should be range from 5 – 20% of total calories from carbohydrate. For someone consuming an average of 2000 calories/ day this would equate to no more than 100 grams of carbohydrate per day. But it can be as low as 20 grams of carbohydrate per day. It really depends on the person, the fitness level, their age and any degree of insulin resistance (loss of sensitivity to insulin and inability to utilize blood glucose for fuel) that a person has. If this leaves you totally blank about how much carbohydrate we are talking about here then know that a typical piece of sandwich bread or a small apple has about 15 grams of carbohydrate.
But the reason it’s important to point out that a ketogenic diet is not just a low carbohydrate diet is because the tendency is that when a person lowers their carbohydrate intake then they usually will raise their intake of protein in the form of meat, chicken, fish and eggs to make up for the calories not consumed from bread, pasta, fruit and other high carbohydrate foods.
So this leads to the next “not” statement about a ketogenic diet. A ketogenic diet is not a high protein diet but rather a moderate protein diet. Protein must be consumed moderately in order for the diet to be ketogenic. This is because protein can be converted to glucose by the body. So a high amount of protein in the diet can increase glucose in the blood and prevent ketones from being produced. (See prior post linked above.)
Since the purpose of a ketogenic diet is to promote the production of ketones then eating high amounts of protein would be counterproductive. But this is exactly what often happens when people attempt to follow a low carbohydrate diet to achieve ketosis. From a percentage standpoint a moderate level of protein would be anywhere from 10-15% of calories from fat. For a 2000 calorie/day intake this would be no more than 75 grams of protein/day. For a reference point that is about three 3 ounce servings of cooked meat, poultry or fish per day.
That brings us to last statement that a ketogenic diet IS a high fat diet. Unlike carbohydrate or protein, fat cannot be converted to glucose. High fat translates to 65 to 85% of calories from fat. The upper level of 85% I would venture to say is more fat than most people just learning about a ketogenic diet have ever consumed in a given day in their life. So you can see how this might be quite an adjustment. For a 2000 calorie diet that equates to roughly 145-190 grams of fat/day. For a visual, this is about 38 teaspoons of olive oil to equal 190 grams. But remember some of your fat comes as part of the protein foods you normally eat and can be healthy fats if the protein is from a healthy source. (see below)
The reason I have given the somewhat wide ranges above is that 1) there is a bit of variance in what “experts” consider to be the percentages of carbohydrate, protein and fat that make for a ketogenic diet and 2) even the experts agree that the exact levels can vary from individual to individual as far as what levels bring an individual into ketosis. It all really comes down to how much carbohydrate and protein an individual can tolerate to keep blood glucose low enough to promote the formation of ketones. Then the balance of the calories should be consumed as fat.
Putting it All Together
So now, given all the detail above, you may be wondering how you actually would implement this. What’s the readers digest version?
To me if someone is considering this way of eating then consider it because you are considering it as a lifestyle. There really is no benefit to using the diet just to lose weight and then going back to the way you normally eat. Much of the benefit of being predominately in ketosis comes from the therapeutic effect it may have on health for the longterm.
If you are just learning about a ketogenic diet and want to try it I would recommend starting out by limiting your carbohydrate intake and increasing your fat intake as described above. Remember that most vegetables, other than root vegetables, are negligible in carbohydrates and you should use these liberally. Avoid the temptation to eat extra quantities of meat, poultry, or fish to keep yourself full. Cook with and look for ways to add healthy fats to your diet. Healthy fats include:
- Olive oil – drizzle liberally on, well anything! Certainly on salads, but also on any raw vegetable that you’ve sliced up or lightly sautéed, steamed or roasted
- Grassfed butter or ghee, also great on sautéed, steamed or roasted vegetables
- Avocados and avocado oil
- Coconut oil
- MCT oil which is made from coconut oil. Consider blending it into your morning coffee or into smoothies.
- Nuts and nut butters such as almonds, cashews, pecans, brazil nuts, hazelnuts
- Fat from grassfed beef, pastured pork and wild caught seafood
- Egg yolks, preferably organic, from pastured hens
Along with increasing your fat intake, begin to pay attention to how much carbohydrate you eat and how you feel. As you lower your carbohydrate intake and if you actually are in ketosis, you may not feel great for a few days. Most people get beyond this as their bodies adapt to burning ketones for fuel.
And finally be aware that if you increase your fat intake without simultaneously decreasing your carbohydrate and protein intake you may gain weight!
Testing For Success
The above is just dabbling with the diet. There are great benefits to health, blood sugar and lipid metabolism if you eat a lower carbohydrate diet and consume predominately healthy fats, avoiding unhealthy fats. If you do just that, then in my opinion you are doing great! But if you want to follow a ketogenic diet you will need to test for the ketones your body is producing.
Testing can be done two ways. Urine strips are an inexpensive and easy method. Ketones in your urine show that you are producing ketones. These ketones are the extra that your body did not use and are being spilled over into your urine as waste. But the longer a person adheres to a true ketogenic diet then the more efficient their bodies become at using the the ketones for fuel. At that point the level of ketones in the urine may decrease. That’s why many experts recommend testing the blood for ketones which can be done with a device that uses blood from a finger prick much like a home glucose monitor.
If you think you’d like to follow a ketogenic diet I recommend becoming educated. One great source that I recommend is “Keto Clarity” by Jimmy Moore. (This is an Amazon affiliate link and I will be compensated if you purchase through this link.) And if you feel you need one on one help to accomplish your health and nutrition goals you may contact me with any questions or to discuss how I might be able to assist you. Of course, if you plan to adopt any new diet then it is always recommended to speak with your doctor first.