Whether you are just starting on your keto journey or you’ve been doing it for a while, at some point you may well look at adding intermittent fasting to your plan.
Often seen as part of the current weight loss health trend, fasting has been around for thousands of years and it has some well-researched and important health benefits besides helping you to lose a few pounds.
Many people who follow a ketogenic lifestyle also practice intermittent fasting. The good news is that it’s not as difficult as many people think.
But let’s start at the beginning.
What is Keto?
The ketogenic or keto diet, is a low-carb, high-fat diet that promotes fat for energy use rather than glucose. This state is called ketosis and is achieved by limiting carbohydrate intake, which prompts the body to burn fat stores instead of carbohydrates for fuel. Along with the keto diet, many people incorporate intermittent fasting into their routine to further enhance the benefits. Intermittent fasting involves periods of fasting and eating within a specific time period. In this article, we'll explore the benefits of combining keto with intermittent fasting and how it can help with various health conditions.
What is Intermittent Fasting?
Intermittent fasting means taking a break from eating. It’s a type of eating pattern in which you alternate periods of fasting with periods of eating. There are several variations including alternate-day fasting, periodic fasting, and time-restricted feeding.
Time-restricted feeding is a popular form of intermittent fasting where you limit your daily eating to a specific time period, usually an 8-hour window. For example, you may eat from 10 am to 6 pm and then fast for the remaining 16 hours of the day. Intermittent fasting and time-restricted feeding can be used together.
Time-restricted feeding: With this variation, your eating window is limited to a specific timeframe, usually between 6 and 10 hours. The 16/8 method also falls under the time-restricted feeding category. With the 16/8 phase, you fast for 16 hours and consume all your daily calories within an 8-hour window.
Alternate-day fasting: Alternate-day fasting involves alternating between fast days and eating days. On fasting days, you either consume zero calories or limit your calorie consumption.
Periodic Fasting: This refers to longer fasting periods extending beyond the typical 16-24 hour fasting window. It involves fasting for multiple consecutive days or a few times each week.
One Day A Meal (ODAM): A more hardcore version of intermittent fasting where you have only one meal per day.
Benefits of Keto and Intermittent Fasting
Of course, one of the main reasons that people try intermittent fasting and pair it with a ketogenic lifestyle is to lose weight. But there are lots of other benefits that come from regular fasting. It’s a powerful combination that can help you achieve your health goals. By restricting your carbohydrate intake and incorporating periods of fasting, you can switch your body from using glucose for energy to using fat. This metabolic switch has been shown to have numerous benefits for weight loss, insulin levels, and overall health. Let’s look at a few of those benefits in more detail.
Weight Loss and Fat Loss
Weight loss and fat loss are two terms that are often used interchangeably, but they are not the same in the context of keto and intermittent fasting.
Weight loss: Weight loss refers to a decrease in overall body weight
Fat loss: Fat loss involves the reduction of body fat while maintaining or increasing muscle mass.
Since both methods force the body to rely on stored fat for energy instead of glucose, keto and intermittent fasting can help achieve both weight loss and fat loss.
Intermittent fasting may also help increase ketone levels in the body, which can further promote fat burning and improve metabolic health. By reducing calorie intake during periods of fasting and regulating food intake during non-fasting periods, individuals can achieve substantial weight loss results over short periods of time, typically within a matter of weeks.
Overall, the combination of keto and intermittent fasting can lead to enhanced fat loss and substantial weight loss in short periods of time.
Improved Insulin Resistance
Insulin resistance is a metabolic condition in which cells in the body become resistant to the effects of insulin, leading to high levels of insulin in the blood. This can over time cause a range of health problems, such as increased risk of type 2 diabetes, heart disease, and other metabolic disorders. Check out our other blog posts onKeto and Diabetes and aboutthe effects of sugar on the human body.
The good news is that the combined keto and intermittent fasting plan can greatly improve insulin resistance. One of the primary ways it does this is by keeping glucose levels steadier than typical carbohydrate-heavy diets.
When you eat a lot of carbohydrates, the body has to produce a lot of insulin to help manage the glucose in the blood. This can lead to spikes and crashes in blood sugar levels, which can cause problems for those with insulin resistance. The low-carb nature of the keto diet and the fasting periods in intermittent fasting help to avoid these spikes and crashes, allowing the body to better regulate its insulin levels.
In addition, the combined keto and intermittent fasting plan also reduces insulin levels over time by promoting the use of fat for energy instead of glucose. When the body is in a state of ketosis, it burns fat for energy, which means less insulin is needed to manage glucose levels. As a result, the body becomes more sensitive to insulin, and the risk of insulin resistance decreases.
Lower Blood Pressure
High blood pressure, also known as hypertension, is a serious condition that can lead to heart disease, stroke, and other complications.
Fortunately, keto and intermittent fasting plans can work together to help lower blood pressure and reduce the risk of these conditions.
One of the ways that keto with intermittent fasting can lower blood pressure is through the reduction of insulin levels. As mentioned in the previous point, when the body is in a state of ketosis, it burns fats for energy instead of glucose. Lower insulin levels and an increased sensitivity to insulin has been linked to a reduction in blood pressure.
Intermittent fasting can also have a positive effect on reducing inflammation in the body, which is another factor that can contribute to high blood pressure. Inflammation is the body's response to injury or infection, but chronic inflammation can lead to a host of health problems, including hypertension. By incorporating periods of fasting into your routine, you can help to reduce inflammation and improve overall health.
Additionally, keto and intermittent fasting plans can help to improve blood sugar control and reduce the risk of other conditions that are commonly associated with hypertension. These include type 2 diabetes, metabolic disease, and heart disease.
Increased Energy Levels
Another common benefit associated with both a keto diet and intermittent fasting is increased energy levels. When the body uses fat for energy instead of glucose, many people report feeling more alert and focused throughout the day.
It is worth noting that physical activity can also increase energy levels, and combining a keto diet and intermittent fasting with regular exercise can lead to even greater benefits in terms of fitness results and overall energy levels.
Reduced Risk of Metabolic Diseases
Following a keto diet with intermittent fasting has significantly reduced the risk of metabolic diseases. One of the key ways in which this combination works is by improving insulin sensitivity and blood sugar control, which are major factors in preventing conditions such as type 2 diabetes and metabolic syndrome.
In conclusion, following a keto diet with intermittent fasting can greatly reduce the risk of metabolic diseases such as type 2 diabetes and metabolic syndrome. This combination improves insulin sensitivity and blood sugar control, resulting in increased energy levels and improved overall health.
Improved Heart Health
Keto with intermittent fasting is a promising approach for improving heart health. Several studies have shown that this combination can have a positive impact on markers of cardiovascular health, including decreased levels of cholesterol, LDL (bad) cholesterol, and triacylglycerol concentrations.
In one study, participants who underwent alternate-day fasting for eight weeks saw a significant decrease in their LDL cholesterol levels, as well as reductions in their overall cholesterol and triacylglycerol concentrations. 
Check out our blog post onKeto & High Cholesterol.
In addition to these short-term improvements, fasting may also have long-term benefits for heart health. By exposing the body to periods of fasting, it may be possible to promote higher levels of metabolic adaptations and improved muscle synthesis. This can lead to a more efficient metabolism and better response to post-workout meals, both of which may contribute to improved cardiovascular health over time.
A few other benefits of intermittent fasting are:
- It changes your relationship with food. People who embrace the lifestyle find that they crave bad food choices less and seem to feel full quicker. This may be one of the reasons why it is often used as a therapy for those with diabetes. Not only do you see weight loss but in some cases, insulin resistance can be prevented or even reversed.
- Fasting should help you lose troublesome visceral fat more quickly. This is the fat that wraps around vital organs in the body such as the liver and which causes inflammation and is thought to play a big role in the development of diseases such as cancer.
- Other studies show that fasting may well have a profound effect on helping to boost the immune system. On top of that, you should find that regular fasting is likely to boost your energy levels and improve your sleep.
Why Keto and Intermittent Fasting Complement Each Other
It can take a couple of days once you start the keto diet to get into ketosis. Combining your dietary change with intermittent fasting can ease you into this process faster – in some cases, it can deepen your ketosis and even prevent you from having that disheartening keto flu with symptoms such as loss of energy and headaches.
When it comes to weight loss, intermittent fasting may work with keto to burn off those stubborn fat stores in the body. In one study with insulin-resistant patients, using intermittent fasting produced improved biomarkers related to general health, and decreased fat mass, all while still maintaining muscle mass.
Getting Started with a Keto Diet and Intermittent Fasting
When getting started on a keto and intermittent fasting diet, these are the steps to go through:
- Choose a fasting window: The first step is to choose a fasting window that suits your lifestyle. The most popular windows are 12 and 16 hours. A 12-hour window means that you can eat anything you want for 12 hours and then fast for 12 hours. A 16-hour window means you can eat anything you want for 8 hours and then fast for 16 hours.
- Sleep also counts: You could schedule your time around your sleep schedule. Some people prefer to have their breakfast shortly after waking up while others choose to have it later in the day. Keep these in mind as you choose your schedule and then adjust accordingly.
- Stay hydrated and calorie-free: calories break your fast. Stay away from calories during your fast. What you can drink: Water, plain black coffee without added sugar or cream, unsweetened black tea, herbal tea without added sweeteners, sparkling water without added sweeteners.
- Plan meals ahead of time: It’s important to plan the meals you’ll have ahead of time so you don't binge on something you know you shouldn't have (like high-carb snacks) right after your fast. You could even try meal-prepping.
- Eat balanced meals and nutrient-dense foods and avoid processed foods: Avoiding processed foods is for obvious reasons. The reason to eat a balanced meal and nutrient-dense foods is that these will keep you full for longer while on your fast.
Initial Challenges to Anticipate and How to Overcome Them:
- Hunger and cravings: Switching to a new eating pattern can cause cravings and hunger, especially in fasting periods. To overcome this, stay hydrated with either water or herbal teas, get hobbies so you stay distracted and choose nutrient-dense foods during eating periods so you stay satisfied for longer.
- Low energy and fatigue - It can take your body some time to adjust to using fat stores for fuel when you first begin:
- Food in social situations - social situations revolve around food. Fear of missing out may make it more challenging: Communicate your fasting schedule to friends and family to manage expectations, Plan social events during your eating periods, In social gatherings, focus on conversations and activities
Planning and time management - For intermittent fasting, it’s essential to carefully plan and all this can be a challenge for some people, Set clear start and end times by determining fasting and eating schedules that align with your schedule and lifestyle, Plan your meals in advance of your eating periods, Batch cook your meals so you have them available when you need them, have non-perishable keto-friendly meals on hand for if you need them. You can find some right here.
Calculating Your Macronutrient Needs:
As we mentioned in our blog post about the differences betweenlow carb and keto, a keto diet typically involves consuming 70% - 75% of calories from fat, 20. - 25% from protein and between 5 - 10% from carbs. Obviously, these numbers change per your individual goals so it's a good idea to consult with a healthcare professional.
To calculate your own macronutrient needs,
Determine your goals: Start by clarifying your specific goals, weight loss, muscle gain or weight maintenance. Understanding your objectives will guide you through your calculations
Assess your activity level: Consider your daily activity level, including both exercise and non-exercise activities.
- If you’re new to Time Restricted Feeding, ease into it gradually. Begin with shorter fasting windows such as 12 - 14 hours and gradually increase the duration as your body adapts to the schedule.
- Synchronise your fasting window with natural rhythms: consider starting your fast in the evening after dinner and extending it until the next morning. This is also known as overnight fasting and it follows the body’s natural circadian rhythm.
- Choose an appropriate window: choose a fasting window that suits your lifestyle and preferences. Adjust the time to what works for you.
- Stay hydrated: Drink a lot of water during your fasting windows. You could also drink herbal teas or other zero-calorie beverages to help curb hunger.
- Focus on nutrient-dense meals: when breaking your fast, focus on nutrient-dense foods. Quality protein sources, healthy fats and non-starchy vegetables to support your keto diet while providing essential nutrients.
- Plan meals in advance: Prepare your meals and snacks in advance to ensure they fit your caloric and macronutrient goals. This will help avoid impulsive food choices and make staying on track easier
- Monitor hunger and adjust eating windows: pay attention to your body’s hunger signals and adjust eating windows accordingly. If it’s harder for your body to adjust to a fasting window, consider shortening it and finding other schedules that work for you.
- Use an app: You can use a manual method or get an app from your phone’s app store to track the times for you.
Planning for Time-Restricted Eating Periods
- Tips for easing into intermittent fasting and adjusting the plan as needed
- Start gradually: If you’re new to intermittent fasting, it’s a good idea to ease into it rather than jumping into an extreme schedule. Begin by extending your overnight fast by an hour or two and gradually increase it over time.
- Listen to your body: Pay attention to your body’s signals and adjust your plan accordingly. If you feel excessive hunger, consider shortening your window and modifying your approach.
- Be flexible and adaptable: Remember, it’s about finding a sustainable balance that can be maintained long term
- Prioritise sleep and stress management: Focus on establishing a regular sleep schedule and implementing stress-reduction strategies such as meditation, yoga and deep breathing.
- Seek support: If possible, find people who are on a similar journey to serve as a support system or accountability partners.
- Consult a healthcare professional: If you have underlying health conditions, are on medication or have specific dietary requirements, it’s advisable to consult with a healthcare professional to make sure the plan aligns with your individual needs.
Should I Do a Longer Fast?
hile you can safely introduce intermittent fasting into your lifestyle with little or no impact, it’s important if you want to consider a longer fast to make sure that you check with your GP first.
Longer fasts are anything between two and three days where you stop eating and only take on fluids. This can have some amazing benefits, not least triggering a process called autophagy which is thought to help your body protect against various diseases.
Even if you are fit and healthy, you should always build up to longer fasts slowly and ideally have some supervision to make sure you don’t suffer any adverse effects.
Ever wondered what to stock your fridge with when you go grocery shopping? Our blog onShopping for Groceries and Snacks on Keto in the UK will be an interesting read for you.