Over the past several years, there have been some pretty major shifts in the world of diet and nutrition. Among the most popular nutritional strategies used by many are the keto diet and intermittent fasting. But what, exactly, are these different dietary tools? What are the benefits of making them part of your fitness routine, and how can they be used together effectively?
The Keto Diet Basics
Also known as the ketogenic diet, the ultra-low-carb diet commonly referred to as "keto" was originally created as a treatment for epilepsy in the 1920s. By greatly restricting your intake of carbohydrates — to under 50g per day — the goal of the ketogenic diet is to train your body to run on fat for fuel rather than carbs. In addition to burning fat, this shift in fuel consumption also leads to the production of substances known as ketones — chemicals created by converted fat in order to provide fast fuel for your hungry brain.
And getting your body into this unique state, called ketosis, is the entire goal of the ketogenic diet.
Although the stated benefits of the ketogenic diet are still undergoing research and are subject to some criticism, there is substantial evidence to support the use of keto to lose weight, improve blood sugar levels and balance cholesterol. In fact, some studies even suggest that a ketogenic diet will help to reduce feelings of hunger, supporting your overall weight loss goals.
Introducing Intermittent Fasting
As its name suggests, the practice of intermittent fasting (IF) requires you to refrain of eating during specific intervals. There are lots of versions of this, however. In its most common form, IF asks men to place all of their eating for the day during an 8-hour window and fast for the remaining 16 hours. It's generally recommended that women use a 10-hour feeding window.
By strategically limiting your calorie intake to these specific times, you expand the natural fast that your body undergoes while you sleep. As a result, your body is forced to make certain adaptations — including a shift to burning fat for fuel and adjusting your hormone levels in a way that facilitates muscle growth.
Clearly, there's some pretty significant overlap between the benefits of the keto diet and intermittent fasting. In fact, many people use fasting to induce ketosis.
How can you actually make these approaches part of your wellness routine, though? When it comes to using fasting to induce ketosis, it's important to consider both when and what you eat.
The when of your diet will be dictated by your program of intermittent fasting. As mentioned, the most common method uses feeding and fasting windows every day of the week. Some, however, find it easier to take entire days off from eating — packing all of that fasting time for the week into one massive session. This requires a significant amount of discipline, though, and may not be realistic for everyone.
Fortunately, there isn't a lot of research to suggest that one IF plan is superior to another. The real deciding factor is simply which arrangement works better for you.
Next, the what must be considered. In order to achieve ketosis, your carbohydrate intake must be extremely low. To compensate, your fat intake should be significantly higher than it otherwise would be. For that to happen, you'll need to avoid sugary foods, including fruits, grains and root vegetables. Instead, your diet will focus on meats, dairy, fish and low-carb vegetables like tomatoes and peppers. If your carb intake goes too high, your body will exit ketosis.
The keto diet and intermittent fasting are both highly effective weight loss strategies but require some significant planning and dedication to execute properly.