It would seem that intermittent fasting (I.F.) and keto are two disparate methodologies.
Many bodybuilders, for example, use intermittent fasting in their diet regimen.
Most would never consider going into ketosis, as keto is often thought of in bodybuilding circles as muscle-wasting.
Of course, it doesn't have to be.
While I.F. is not a necessary component of the keto diet, it is helpful for two reasons:
- Getting yourself into a caloric deficit
- Getting into ketosis as quickly as possible
BOTH of the above are 100% necessary for losing body fat, which presumably is one of the benefits you're aiming for when choosing the keto lifestyle.
What is Intermittent Fasting?
According to Wikipedia,
Intermittent fasting (intermittent energy restriction or intermittent calorie restriction) is an umbrella term for various eating protocols that cycle between a period of fasting and non-fasting over a defined period. Intermittent fasting is under preliminary research to assess if it can produce weight loss comparable to long-term calorie restriction.
Wikipedia
Currently, the most prominent I.F. program is the 16:8 protocol, where you fast from 8pm until 12pm the following day (that's 16 hours) and then eat in the 8-hour window between 12pm and 8pm.
Some people use that every day. Some I.F. only infrequently.
Other protocols call for fasting an entire day (24 hours) while some fast for 36 hours or more.
How does I.F. help keto?
The primary objective of a keto diet is to get your metabolism into a state of ketosis, where your body is producing ketones for energy rather than glucose.
It's when you're in this metabolic state that you stand the greatest chance of body fat weight loss.
The secondary objective of keto is to put yourself into a state of negative caloric balance. There is NO WAY to shed pounds without going into a calorie deficit!
And while going on a keto diet will get you into ketosis in 3-5 days, you can accelerate this process by using intermittent fasting.
PLUS, as an added bonus, I.F. is simply the easiest way to put yourself into a caloric deficit.
Here's how to work intermittent fasting into your keto diet
It's rather simple. Let's start at 8pm tonight, as an example. You don't eat the rest of the night (no late night snacks). Tomorrow, skip breakfast and don't eat until 12pm (noon).
Eat your regular keto diet. I like to eat breakfast food for my 12pm meal, so I scramble some eggs and fry some bacon.
I LOVE orange juice, but I refrain. Too many carbs. I just drink water. You can drink tea or coffee, as long as you don't add any sweeteners (e.g., sugar).
At 2pm, I mix up a protein drink (this is what I use). Add some cream and peanut butter powder and creatine. Then I go to the gym and do heavy lifting and moderate cardio (I ride a bike or walk on the treadmill at a fairly fast clip).
Then, about 6, I eat again. Something high-fat, moderate protein, very little carbs. Fish, chicken, beef. Some green leafy veggies.
Right before 8pm, I drink an MRE like Pure Protein (I get it from Costco).
Then I'm done for the night.
Using I.F. and keto concurrently gets me into ketosis within a day or two and I stay on it for the rest of the week. Sometimes longer.
I do “cheat” on some weekends, where I take in near the top range of carbs (50g) rather than sticking to 20. It's hard.
But I try not to deviate too much from the max 50.
Here's a video I found that explains intermittent fasting in much more detail: