The keto diet is an extremely powerful weight loss plan with a ton of benefits. However, combining keto with intermittent fasting (the practice of limiting your meals to certain days/times) can take your weight loss journey to the next level.
The fat burning properties of the ketogenic diet only increase when you pair intermittent fasting and keto. But that’s not all. Several other benefits arise from this combination. Let’s dive into the reasons you’ll see amazing keto plus intermittent fasting results.
First, if you don’t know too much about keto, we recommend our intro article on the benefits of the keto diet. There’s a wealth of great science that proves that keto makes a real difference in weight loss.
Before we dive into fasted keto, let’s take a quick look at intermittent fasting.
What is Intermittent Fasting?
Intermittent fasting is not a diet in the traditional sense. It doesn’t limit what foods you eat or how much food you eat. It’s essentially a meal timing plan. It sets a schedule for when you eat, with long periods of fasting between meals.
We’ll flesh this out in more detail below, but one popular variant of intermittent fasting is called 16:8. On the 16:8 plan, for 16 consecutive hours of the day you will fast (no food, but you can and should drink water) and you will fit all of your meals into an 8-hour block.
One example of the 16:8 plan would be to have your first meal of the day at lunchtime, at noon. From there, you are free to have meals and snacks until 8 PM. Then, from 8 PM until noon the next day, you will return to fasting.
By grouping meals in this way, you kickstart several weight loss processes in your body which dovetail perfectly with the keto diet.
Why Try Intermittent Fasting?
Intermittent fasting might seem too simple to be true—just keep your meals in an 8-hour window, that’s all?
This analysis by Harvard University shows consistent evidence of a link between intermittent fasting and fat loss across several clinical studies. So, it works, but why?
When you go for a long period without food, your body’s insulin levels drop. When this happens, it triggers your body to begin breaking down stored fat to use as fuel. This doesn’t happen when you have meals placed throughout the course of the day because the constant influx of food keeps insulin levels high enough to prevent this fat burning state.
Why Combine Keto and Intermittent Fasting?
Intermittent fasting on keto is such a great plan because they tackle the same goals from different angles. Both are about torching fat by using your body’s natural responses.
Remember, intermittent fasting is about WHEN you eat and keto is about WHAT you eat. This means you’ll go through fasted periods, then eat high-fat keto meals during the other periods. By pairing them, you’ve essentially created a complete weight loss nutrition plan.
Here are the top reasons we recommend intermittent fasting on keto.
1. Fasting Gets You Into Ketosis and Keeps you There
Ketosis is the process of breaking down fat to use as fuel. During this process, your body metabolizes fats in the foods you eat, as well as stored fat in the body, to provide the energy you need.
Here’s where we start to see how the partnership between the keto diet and intermittent fasting pays off big time. Intermittent fasting lowers insulin levels and triggers your body to start consuming fat for fuel, which is exactly what you want to be doing on keto.
Essentially, the keto diet provides a steady intake of fats and intermittent fasting triggers your body to start using those fats for fuel. When you go for an extended period without food (such as those 16 fasted hours in the 16:8 plan) your body gets directed to consume fat, so it begins ketosis in a natural way.
By combining the two your body is pushed into ketosis and remains there for extended periods, causing you to burn fat uninterrupted for hours. Meanwhile, if you go on a keto diet without intermittent fasting, your process of ketosis may be interrupted, or at least slowed down, every time you take in a meal. You won’t be able to avoid carbs entirely on the keto diet and each time you have a few, it’ll slow down the process of ketosis.
2. Increase Fat Burning and Decrease Cravings
Studies have shown that intermittent fasting alone aids in weight loss, even without a restricted diet or conscious calorie reduction.
The keto diet has also shown evidence of contributing to weight loss. Both on their own are good, so putting them together makes sense already, right?
But the truth is that Keto + Intermittent Fasting are greater than the sum of their parts.
Intermittent fasting causes cells to release stored energy to use as fuel. This aids in fat loss because the cells have no energy reserves. The body has to turn to break down fat to get the fuel it needs.
If you try intermittent fasting without keto you may experience intense hunger cravings when your body goes into this fat burning mode. One of the huge benefits of keto is that it suppresses hunger hormones, such as ghrelin, making it possible to enter fasted periods without feeling intense hunger cravings. This enables you to stick to your meal plan and prolongs the periods where you’re burning fat.
3. Repairs Damaged and Pre-Cancerous Cells
Intermittent fasting induces autophagy. This is the process wherein your cells break down old and damaged parts to use for energy and replace them with new parts. Because of this, damaged cells are repaired instead of replicating and spreading, which may prevent cancerous growth of cells. This is great news, especially since autophagy begins with the brain cells.
Meanwhile, the keto diet begins the process of fat breakdown. This takes place in the liver, which pulls in stored fat so it can be used as fuel. The first place the liver pulls stored fat from is the closest and most convenient spot—itself. The keto diet combats fatty liver, which is a leading indicator of diabetes.
By pairing the keto diet with intermittent fasting you can turn back the clock on damage to your body and prevent diseases. This makes it a great combo for both weight loss and long term health.
4. Gives You an Energy Boost
Remember how keto provides an assist to intermittent fasting by reducing food cravings during fasted periods? Well, intermittent fasting makes the keto diet easier as well.
Many people experience increased mental clarity and energy when on an intermittent fasting plan. This energy boost can be key if you’re among those who feel more sluggish or a little less sharp at times on the keto diet. The fact is, carbs are the easiest thing for your body to turn into fuel, and your body fuels the brain first on whatever is most readily available.
Because the keto diet restricts the number of carbs you take in, it forces your body and brain to use fats as fuel. If your body is expecting carbs for fuel and gets fat, it may struggle at times. Intermittent fasting battles this, thanks to that response that lowers insulin levels and begins fat burning. Your body is expecting to receive fat as fuel when insulin levels drop so the metabolism of fat for fuel syncs with your body’s other processes. It provides a big energy boost and a general sense of well being.
5. It Boosts Your Keto Gains at the Right Time
Experts agree that it is not advisable to begin a keto diet and intermittent fasting at the same time. The shock of going from a standard high-carb diet with standard meal-placement to a restricted diet and meal timing can be a lot for your body to take on at once. It can make the adjustment period harder and cause you to give up on the entire plan.
We recommend beginning the keto diet and maintaining it for 2 weeks. This will get you past the tough early stages and into the keto rhythm you’re looking for. By this time, you’ll have battled any keto flu symptoms, such as irritability and headaches, and come out the other side stronger (and leaner). You’ll likely have lost your first few pounds thanks to the keto diet.
Now’s the perfect time to begin an intermittent fasting plan in tandem with keto. Not only will your body be ready for your adjustment, but you’ll also get all the benefits discussed previously on this list. That means increased fat burning and energy. You’ll go from losing the first few pounds to making even more progress toward your weight loss goals.
Keto + Intermittent Fasting Risks
As with any keto diet variation, consult a physician if you have any health concerns. Individuals with diabetes should be careful when beginning any keto plan because ketosis in diabetic individuals can lead to ketoacidosis, which is a dangerous spike in the acid levels in the blood. This is relatively rare, but a physician should be consulted in case you are at risk.
Overall, the keto diet, as well as intermittent fasting, have very low risk if done safely with a solid plan. They are popular and well-regarded partially because they are so safe and get such amazing results. Begin with the 16:8 plan and see where it takes you.
Keto + Intermittent Fasting Rewards
We highly recommend the fasting keto diet to almost all who are looking to make weight loss progress in a safe, fast, and effective way that also provides long-term health benefits. If you’ve begun a keto diet and are seeing results, adding intermittent fasting can supercharge the benefits you see.