For people who combine the keto diet and fasting, there’s a potential to experience mental clarity, an increase of fat burning, and experiencing more energy. A keto diet is when a body burns fat instead of glucose. Combined with fasting, it can create a killer combo. Interested in pairing a keto diet with fasting? As a newbie, it may be a good idea to ease into one of the two first, but in time, combining both can expedite weight loss and offer many other benefits. We discuss everything more in-depth in the Body Reboot book and below are 7 simple yet incredible benefits of fasting. 

What happens when you fast? 

Dr. Bubbs does an excellent job at summarizing what happens when you fast, and why your body will burn through carbs first followed by fat. 

Fasting is the controlled and voluntary removal of all food for a specific period of time. When you fast, your body’s blood sugar and insulin levels begin to fall. To ensure your body (and brain) have energy, your liver releases its glycogen carbohydrate stores to supply organs with glucose and keep blood sugars stable. You typically have enough glycogen in your liver, and muscles, to keep you going for 24-36 hours. Once you’ve exhausted your glycogen stores, your liver produces glucose from the amino acids (via a process called gluconeogenesis).

After two to three days, your low insulin levels will stimulate the breakdown of triglycerides, the kind of fat found in your body-fat stores. The triglyceride is broken down in its three free fatty acids that can be used by virtually all tissues for energy (except your brain) and glycerol backbone is used to make more glucose.

To keep your brain happy, your liver begins to produce ketones – beta-hydroxybutyrate and acetoacetate – which provide your brain with approximately 75% of its fuel requirements. Ketone production can ramp up as much as 70x during fasting. Lastly, during fasting your body pumps out significant amounts of growth hormone (GH) in order to preserve muscle mass and lean tissue.

1. Leads to weight loss

Of course, one of the biggest perks of fasting is weight loss. Harvard Health Publishing discloses how exacting fasting works and how you can use it to your benefit when you’re trying to lose weight. 

High levels of small, dense LDL cholesterol, as well as high triglycerides mentioned above and lipoprotein (a) all serve as reliable markers for cardiovascular disease risk. Fasting has been shown to reduce all three of these parameters. It makes sense that if you abstain from food, your body will breakdown its own fat stores to fuel activity, thus improving your lipid profile.

If you’re overweight, pre-diabetic or diabetic (type-2) fasting can be a powerful tool to reversing chronically high blood sugar and insulin levels, poor metabolic health and CVD risk. Today’s constant snacking society and plethora of processed foods has no doubt contributed to the current obesity and diabetes epidemic. Fasting is a simple, effective and cost-efficient strategy to improve your health.

2. Higher levels of endorphins

In addition to losing weight and experiencing mental clarity, Medical News Today claims that you will have a higher level of endorphins. That means you’re more likely to feel happy and stay in good spirits while you fast. 

Since the body is unable to get its energy from food during fasting, it dips into glucose that is stored in the liver and muscles. This begins around 8 hours after the last meal is consumed.

When the stored glucose has been used up, the body then begins to burn fat as a source of energy, which can result in weight loss.

As well as aiding weight loss, Dr. Razeen Mahroof, of the University of Oxford in the UK, explains that the use of fat for energy can help preserve muscle and reduce cholesterol levels.

A woman with a tape measure around her mouth

When the body has used up glucose stores during fasting, it burns fat for energy, resulting in weight loss.

“A detoxification process also occurs, because any toxins stored in the body's fat are dissolved and removed from the body,” he adds, noting that after a few days of fasting, higher levels of endorphins – “feel-good” hormones – are produced in the blood, which can have a positive impact on mental well-being.

3. Mental clarity

As we’ve hinted at throughout this article so far, Ruled.me discloses that fasting can result in mental clarity. Having a foggy brain never helps when you’re trying to accomplish things, which is why mental clarity is a fantastic perk of fasting. 

Once your body is keto-adapted, your brain can effectively run on ketones, which are derived from fat breakdown in the liver.

Fat is considered one of the most energy-efficient fuels for your body to run on, and your brain is a huge consumer of energy.

Most high-carb advocates are campaigning on the deprivation your body undergoes when you do not continuously refuel on grains and fruits. They want you to be carrying around an apple and a granola bar wherever you go, but the beauty with keto is that you don’t.

Even if your body is out of glycogen (which it most likely is if you’re in ketosis), it can rely on the abundance of fat from the foods you eat and stores you have. That means your powerhouse of a brain can run full power all the time. Less mental fogginess, and more focus.

Mental Clarity and Keto

As you get used to fasting, you should start to fast naturally. Meaning, only eat when you’re hungry. Don’t plan your fasting – let it happen naturally.

4. Improves eating patterns 

Lifehack says that fasting can also improve your eating patterns and make you more wary of your food selections. It does a great job at helping you discern between healthy and unhealthy foods and how you can change your bad habits moving forward.  

Fasting can be a helpful practice for those who suffer with binge eating disorders, and for those who find it difficult to establish a correct eating pattern due to work and other priorities.

With intermittent fasting going all afternoon without a meal is okay and it can allow you to eat at a set time that fits your lifestyle. Also, for anyone who wants to prevent binge eating, you can establish a set time in where you allow yourself to eat your daily amount of calories in one sitting, and then not eat till the following day.

5. May help treat cancer 

Ruled.me reveals that fasting may even help treat cancer! Here’s why that may be the case: 

Although there is little to no literature on the effects of 2 or 3 day fasts on muscle loss in humans, many clinical trials are currently being conducted on the effects of 2 or 3 day fasts on cancer patients.

In initial case studies, people who were undergoing chemotherapy voluntarily fasted for anywhere between 48 to 140 hours. Each person reported less side effects and an improved quality of life regardless of how long they fasted.

This implies that fasting for 2 days to a week can have a protective effect on the cells in the body while they are undergoing intense bouts of toxicity.

Fasting and Cancer

Other studies have found that fasting was as effective as chemotherapeutic agents in delaying progression of different tumors and increased the effectiveness of chemotherapeutic drugs against melanoma, glioma, and breast cancer cells. Although this research may not apply to your life, it does suggest that intermittent fasting can help support your body in times of toxic stress.

6. Promotes longevity 

As you continue to improve your health by combining the keto diet and making positive decisions in life, Lifehack says that the changes can help you live longer. That makes perfect sense if you think about it! 

Believe it or not, the less you eat the longer you will live. Studies have shown how the lifespan of people in certain cultures increased due to their diets.

However, we don’t need to live amongst a foreign community to reap the benefits of fasting. One of the primary effects of ageing is a slower metabolism, the younger your body is, the faster and more efficient your metabolism. The less you eat, the less toll it takes on your digestive system.

7. Improves lipid profile

Last but not least, Dr. Bubbs explains how fasting can improve your lipid profile. If you’re wondering what lipids are, they affect how your heart functions. You may be able to keep your heart healthy by going on the keto diet and fasting to reduce the risk of heart disease and stroke. 

High levels of small, dense LDL cholesterol, as well as high triglycerides mentioned above and lipoprotein (a) all serve as reliable markers for cardiovascular disease risk. Fasting has been shown to reduce all three of these parameters. It makes sense that if you abstain from food, your body will breakdown its own fat stores to fuel activity, thus improving your lipid profile.

If you’re overweight, pre-diabetic or diabetic (type-2) fasting can be a powerful tool to reversing chronically high blood sugar and insulin levels, poor metabolic health and CVD risk. Today’s constant snacking society and plethora of processed foods has no doubt contributed to the current obesity and diabetes epidemic. Fasting is a simple, effective and cost-efficient strategy to improve your health.

Bonus Tips: 

Harvard Health Publishing gives us another tip, which is to avoid sugars and refined grains. We agree! Stay away from snacking and be mindful about what you’re eating. Implementing these small habits over time will hopefully help you maintain bigger and better practices moving forward. 

Avoid sugars and refined grains. Instead, eat fruits, vegetables, beans, lentils, whole grains, lean proteins, and healthy fats (a sensible, plant-based, Mediterranean-style diet).

Let your body burn fat between meals. Don’t snack. Be active throughout your day. Build muscle tone.

Consider a simple form of intermittent fasting. Limit the hours of the day when you eat, and for best effect, make it earlier in the day (between 7 am to 3 pm, or even 10 am to 6 pm, but definitely not in the evening before bed).

Avoid snacking or eating at nighttime, all the time.

Check out the Body Reboot book to learn more about the keto diet and how fasting may further improve your ability to lose weight and improve your health. For a limited time, you can get a free copy of our book! Help us cover shipping and head over to this page to get a free copy.

Sources: Dr. Bubbs, Harvard Health Publishing, Medical News Today, Ruled.me, Lifehack