The Science Of Intermittent Fasting
Intermittent fasting is an eating schedule that alternates between fasting and feeding. You set a time window for eating, eat only within that window, and fast the rest of the time.
For example, you might eat only between the hours of 10:00 AM and 6:00 PM .
IF is not a diet in the conventional sense, but rather, an ancient pattern of eating.
Historically, during hunter-gatherer days and even earlier, our ancestors were often in a natural fasting state while seeking food.
Modern industrial agriculture may have eliminated hunger for most people, but the widespread availability of packaged, processed food has also led to many new diseases stemming from obesity and high blood sugar.
Essentially, it turns out that having food available all the time is unnatural, and modern approaches to fasting work by reintroducing periods of scarcity for health purposes.
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For most people today, fasting is a voluntary act, whether undertaken for health or religious reasons.
The health benefits of fasting relate to cellular pathways that remain inactive or minimally active when youre fully fed, such as:
- Growth hormone release
In a nutshell, avoiding food intake while fasting enables your body to naturally cleanse, repair and regenerate cells and tissues for optimal function.
Added bonus benefits include better cognition, brighter mood, and greater energy levels.
How Much Weight Can You Lose On : 8 Diet
To lose weight on the 16:8 diet, its important to match the fasting with healthy eating and exercise. If done so correctly, theres a typical weight loss of around seven to 11 pounds over a ten week period. This is according to a review of 40 different studies published in Molecular and Cellular Endocrincology who found that on average, someone weighing just over 90kg would lose 5% of their total body weight in the ten week period.
A 2018 study published in the Journal of Nutrition and Healthy Eating revealed that the 16:8 diet plan can help people lose weight, without having to count calories as the 8-hour fast produces the same kind of calorific restriction and weight loss.
However, whether theres a distinct weight loss advantage achieved on the 16:8 diet compared to other diets remains to be seen. Some studies have demonstrated that theres almost no difference between people who do intermittent fasting compared those who count calories and cut back on unhealthy food.
Intermittent Fasting & Keto Diet Results Weightloss
This keto breakfast recipe is chock filled with fiber-filled veggies, savory breakfast meats, as well as buttery eggs. The very best part? Youll be ultra-full by the time youre finished with this dish, as well as it just costs you 5 internet carbs. To keep it Bulletproof, use bacon or sausage from pastured pigs without fillers.
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The Ketogenic Diet Keeps You Satisfied
Another great perk of the keto diet is its high level of satiety.
Not only does ketosis itself tend to stifle hunger, but the high level of healthy fat in the keto diet also makes it much easier to stay satisfied in a fasted state and eliminates those intense feelings of hunger and cravings throughout the day.
This is perfect for someone doing intermittent fasting.
How To Do Intermittent Fasting 16/8
To do intermittent fasting correctly and reap all the health benefits, heres what to do:
- Pick your fasting window: Choose what the hours of fasting will be. The easiest approach is to have an early dinner and skip your morning breakfast. For example, eating only from 1 p.m. to 9 p.m.
- Have healthy meals during your eating window: A bad diet during your eating window can offset the metabolic benefits of intermittent fasting, so stick to nutritious whole foods. Heres a list of the best keto-friendly foods to eat.
- Eat fatty, satisfying meals: While you dont need to be keto to try intermittent fasting, eating fatty foods will make it a lot easier and sustainable. Keto foods are healthy and satisfying, so you wont be hungry during your fasting window. Practice smart snacking and youll do great.
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What Is A Ketogenic Diet
A ketogenic diet means eating high-fat, moderate-protein, and low-to-no carbohydrates.
When the levels of ketones in our blood get elevated, we enter the metabolic state called ketosisthe root of the term keto diet.
The calorie breakdown of a typical ketogenic diet looks like:
- 70-80% of calories from fat
- 15-30% calories from protein
- 0-10% calories from carbohydrates
Most ketones pack more energy per unit than carbs. They can also fuel the vast majority of your cells. For the few other types of cells that need glucose, your body will synthesize it from protein. This is a natural process called gluconeogenesis.
Intermittent Fasting Or Keto Which Is Better
If you don’t really enjoy being active then exercising is a hard thing to do. Exercising just to lose weight is even harder. So what is the preferred weight loss method for people who don’t like to exercise? Most of the times it’s simply to eat less. In second place comes cutting out carbs. But in the recent years we’ve seen a popularity in intermittent fasting. At the same time, the ketogenic diet has seen a huge growth as well but isn’t as popular as intermittent fasting. So which method is better? The short answer is: it’s not that simple. Firstly, the methods above can all help you lose weight but some have benefits beyond just weight loss. And then there are feasibility factors to consider. Some method is a lot harder execute than the others.
Why eating less and cutting carbs work
Most of us have done it and know that it works: eat less and lose weight. Cut out all carbs and lose weight. These methods work well in the short term because your body loses water and you burn more than you consume. But with the eating-less approach your body realises after a while that it’s getting a lot less energy in form of food than it’s used to so it might slow down your metabolism. This is a natural adaptation process and leads to the well-known plateau many people experience.
Intermittent fasting describes different types of eating intervals. The most popular types of IF are:
Which is better?
The bottom line
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Can You Have Cheat Days On Intermittent Fasting With Keto
If your key goal is to lose weight, a cheat day on this diet will not inhibit progress. According to research, it suggests that you should stick to keto friendly foods to prevent blood sugar spikes and reversing ketosis.
So long as your chosen intermittent fasting method allows a day of food, then it is fine.
Should You Be Worried About Refeeding Syndrome
Some legitimate health complications can arise when you fast or are malnourished for longer than 5 days. One of these complications is called refeeding syndrome, which is caused by potentially fatal shifts in fluid and electrolyte balance that can happen when we eat after a period of undernourishment.
This happens because the concentration of fluids and minerals in our body relies heavily on what we eat. Low carbohydrate diets, like the ketogenic diet, increase the excretion of vital minerals like sodium and potassium.
If you add a prolonged fast onto the ketogenic diet, you can lose an unhealthy amount of these essential minerals.
Fasts that are shorter than 5 days, however, arent likely to cause issues especially if you break your fast with a low carbohydrate meal that is filled with mineral rich foods. A meal with dark leafy greens, avocado, and salmon with some unrefined salt would be an ideal way to break a longer fast.
During a shorter fast that lasts less than 24 hours, however, you wont have to worry about refeeding syndrome at all. Either way, it may be best to check out the mineral supplements that we recommend in this article to ensure proper mineral balance.
But what about muscle? Its only common sense that consuming no protein and less calories will lead to an unhealthy amount of muscle loss. Thats right it is only common sense.
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Can You Do Keto And Intermittent Fasting Together
If your goal is losing weight, combining keto and intermittent fasting would most likely give you the results youre looking for, but its important to remember that it may not work for everyone. Fasting intermittently while following a high-fat, low-carb diet may help you lose weight faster, but it is unnecessary to reach actual ketosis.
Both diets are incredibly restrictive and challenging to follow long-term. If you decide to try keto fasting weight loss, it is not recommended to start both diets simultaneously. If adding IF to the keto diet, consider beginning with a small fasting window while you sleep to avoid skipping meals. You may also consider following a modified keto diet that allows for healthy carbohydrate foods such as fruits, whole grains, and starchy vegetables.
As with any nutritional changes, it is important to monitor your food intake and not lose sight of its role in your day-to-day functions. Adequate nutrition is more than just a tool for burning fat it is necessary for your body to function.
What To Eat While Intermittent Fasting
During your fasting window, you shouldnt eat anything. During your eating window, enjoy nutrient-dense keto foods like healthy proteins, vegetables, and fats.
Avoid breaking your fast with processed foods, carb-heavy meals, and dirty keto foods, as these can hinder the health benefits of fasting in the first place.
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Intermittent Fasting Vs Keto: Which One Is The Best
Both keto diet and intermittent fasting are practiced for weight loss. And it is important to know which the best among intermittent fasting vs keto is.
As we all know that diet remains in the topmost position for the weight loss solution ever. So itâs better not get confused between the well-known weight loss explication. Because, the truth is that everyone is not the same, so you canât pick one haphazardly. The adjudication needs to be made based on your body demand, rather than whatâs trending in social media.
Tips To Combine Intermittent Fasting With A Ketogenic Diet
Luisa Torres, PhDLuisa is a science communications manager at LifeOmic and neuroscientist and science writer covering topics related to aging, metabolism, and brain health.
Luisa Torres, PhDLuisa is a science communications manager at LifeOmic and neuroscientist and science writer covering topics related to aging, metabolism, and brain health.
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Why Combining Intermittent Fasting With Keto Has Become Popular For Weight Loss
Doing keto or IF can help with weight loss in the short term, though each diet is very restrictive, so they certainly arent for everyone.
But how about combining them? Could two be better than one?
First, in some experts view, it does make sense to pair the two approaches. The keto diet increases levels of ketones in the body during times of fasting, ketones are also increased. The brain will rely less on glucose for energy when in a state of nutritional ketosis. Therefore, the transition into a fasted state during the day eventually becomes seamless after eating low-carb or ketogenic for a few weeks, says Dominic DAgostino, PhD, associate professor at the University of South Florida in Tampa and founder of KetoNutrition.org.
This is a strategy that practitioners counsel patients on at the Cleveland Clinics Functional Ketogenics Program. Adding intermittent fasting can take things up to the next level, says the Clinics Logan Kwasnicka, a certified physician assistant at the Cleveland Clinic in Ohio. That next level may be overcoming a weight loss plateau, as people may eat fewer calories when doing IF. It can also be a natural progression from a keto diet for those who feel satiated eating so much fat and arent bothered by shrinking their eating window.
Insulin Resistance And The Importance Of Nutrition
And there are a couple of reasons for that. Number one, they have insulin resistance. Okay. And that’s gonna take some time to fix that. And when you have insulin resistance, you just don’t pull the nutrients that much. So you’re always gonna feel a little unsatisfied. So that tends to cause you to eat more. The other reason why you might not feel satisfied is the food that you’re eating is not nutrient-dense. Okay. When you do grass-fed beef, oh my gosh, it has so many more nutrients than corn-fed beef. And you won’t know it until you try it. So even though it might have more of an I don’t know, earthy taste to it, or a kind of a, a different taste, it’s way more nutrient-dense, more omega-three fatty acids there are even phytonutrients in there because the cow has eaten a lot of grass.
Keto Can Fuel And Protect Fasting
Studies show that intermittent fasting can increase the production of stem cells in the intestines, muscles, and brain. At the same time, IF preserves the ability for stem cells to regenerate independently in the long term.
Yet ending a fast with sugary processed foods can lead to precancerous lesions and increased cancerous activityespecially in the intestines and liver.
Combining intermittent fasting with a high-fat, low-carb keto diet fertilizes the fresh crop of new cells with energy-packed ketones, while protecting them from the damage wrought by carbs and insulin.
How Long Should You Intermittent Fasting On Keto
Research suggests that whilst on keto, intermittent fasting methods should change between long and short periods. This is to ensure you do not encounter severe nutrient deficiency. To prevent this and ensure you are safe, you can take nutrient supplements alongside the diet to attain those you may be deprived or low of.
Some may also develop refeeding syndrome. This is where the body sees a fatal shift in fluids and electrolytes due to undernourishment. These shifts can cause detrimental effects to your health and hormones.
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Who Should Try Combining Intermittent Fasting And Keto
If you’re looking to shed pounds quickly, the IF and keto combo could be the right one for you. It may depend on what pre-existing health conditions you have.
“Individuals with type 2 diabetes may benefit from ketogenic diet and IF as it may aid with weight loss and potentially allow you to reduce your medications,” says Gyimah. People who’ve been diagnosed with prediabetes may also see similar benefits, including dropping pounds and reducing insulin, Gyimah adds.
However, if you have type 1 diabetes, keto might not be safe. People with type 1 who try this diet may be susceptible to a condition called diabetic ketoacidosis, Gyimah says, which basically means the buildup of ketones in their bodies can be dangerous. Regardless of what health conditions you have, it’s best to check in with your healthcare provider before starting any dietary changes, especially keto or IF.
Try The Most Popular/effective Method
The most popular method is 16/8. Otherwise known as the timed restricted eating routine. This involves 16 hours of fasting and 8 hours of eating. During the eating window you should consume balanced keto meals. Either 2 large meals or 3 smaller meals. Avoid snacking to maximise results and to maintain a strong digestive system. Overeating can cause your digestive system and your metabolism to slow down. This can cause stomach issues and weight gain.
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Best Foods For Intermittent Fasting
Here is the list of 9 best foods for intermittent fasting that we recommend.
These 9 secret foods will enhance the effectiveness of fasting. IF will only have a positive effect on your body when you carefully monitor your diet during the eating period. Fasting for 12-16 hours and then eating calorie-packed foods will turn your hard work into no work. For 100% results, you need to have an optimally balanced diet. Following are the 9 best foods for intermittent fasting:
Combining Keto & Intermittent Fasting: Benefits + Challenges
Although they may seem different on the surface, Keto and IF share many similarities. They both encourage the body into a Ketogenic state, and have the potential to increase fat burning. Theres also a lot of crossover between the potential wellness benefits, from heart health to insulin sensitivity.
You may be wondering whether it’s safe and effective to combine the two — extending your fasting window, and consuming a high-fat diet during your eating window.
The good news is that because both diets work via similar underlying mechanisms, they have the potential to complement each other. Keto and IF act synergistically towards the same end goal – making the body more adept at burning fat as a fuel. You might also find that the common challenges of each diet are canceled out when you combine them together:
- Restricting food intake through IF may make it easier to get into and stay in ketosis, as this kick-starts the depletion of carbohydrate levels.
- A Ketogenic diet may make intermittent fasting feel easier as your body becomes more fat-adapted, and you feel more satiated from consuming higher-fat foods.
- If youre fairly new to Keto, you may find that IF helps you stick to the diet, as you have fewer meals to think about and prep.
That being said, there are some potential drawbacks to be aware of:
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