Fasting On Keto: How Long Is Too Long?

Fasting for too long on the keto diet can have adverse effects on your health. The keto diet is a restrictive high-fat diet, and intermittent fasting restricts the number of hours you will be eating. There is a lack of research on the long-term effects of combining the two, so it's unclear exactly what you're getting into if you try them together.

Combining the two diets may be too restrictive, making it difficult to stick to the low-carb count and confined eating window. Even children who follow keto to help control epilepsy have a hard time adhering to the plan.

Before deciding to follow keto and IF together, be sure to consult your healthcare team. Your provider can help you determine whether this combined diet plan is a good fit for you, and then they can adjust any meds you’re on to help increase your chances for success in the safest way possible.

The benefits of combining keto and intermittent fasting

The ketogenic (keto) diet and intermittent fasting are two of the most popular health trends. Both methods are used by health-conscious people to lose weight and control certain health conditions. While both approaches have solid research backing their purported benefits, many wonder if it is safe and effective to combine the two.

Intermittent fasting is an eating method that alternates between calorie restriction (or fasting) and normal food consumption during a specific time period. There are many different types of intermittent fasting routines, including the 5:2 method, the Warrior Diet, and alternate-day fasting. The most popular type of intermittent fasting is the 16/8 method, which involves eating during an eight-hour timeframe before fasting for 16.

The keto diet is a high-fat, very low-carb way of eating. Carbs are typically reduced to 20-50 grams per day, which forces your body to rely on fats instead of glucose for energy. This metabolic process is called ketosis, where the body breaks down fats to form substances called ketones, which serve as an alternative fuel source.

Benefits of Combining the Two

Combining the keto diet with intermittent fasting is likely safe for most people. It could offer the following benefits:

• May help you reach ketosis faster: Intermittent fasting may help your body reach ketosis quicker than the keto diet alone. During fasting, your body shifts its fuel source from carbs to fats. Insulin levels and glycogen stores decrease, leading your body to naturally start burning fat for fuel.
• May lead to more fat loss: Combining the keto diet with intermittent fasting may help you burn more fat. Intermittent fasting boosts metabolism and promotes thermogenesis, or heat production, which may help utilise stubborn fat stores.
• May preserve muscle mass: Intermittent fasting may preserve muscle mass during weight loss and improve energy levels, which may be helpful for keto dieters looking to improve athletic performance.
• May reduce hunger: Studies show that intermittent fasting can reduce hunger and promote feelings of fullness, which may aid weight loss.

Who Should Try Combining the Two?

Combining the keto diet with intermittent fasting may be beneficial for people with type 2 diabetes or prediabetes, as it may aid with weight loss and potentially allow for a reduction in medications. However, if you have type 1 diabetes, the keto diet might not be safe. People with type 1 who try this diet may be susceptible to a condition called diabetic ketoacidosis, where the buildup of ketones can be dangerous.

Additionally, pregnant or breastfeeding women and those with a history of disordered eating should avoid intermittent fasting. People with certain health conditions, such as diabetes or heart disease, should consult a doctor before trying intermittent fasting on the keto diet.

Combining keto and intermittent fasting may help you reach ketosis faster and lead to greater fat loss. However, while this combination may work for some, it is not necessary to mix both approaches, and some people should avoid this combination. As with any major lifestyle change, it is advisable to speak to your healthcare provider first.

How to reach ketosis faster

Ketosis is a metabolic state in which the body burns fat for energy instead of carbohydrates. This is achieved by reducing carbohydrate intake to a minimum and increasing the consumption of healthy fats. While this process usually takes a few days, there are ways to speed it up.

Reduce Carbohydrate Intake

The first step to reaching ketosis is to reduce your carbohydrate intake. Aim for a maximum of 50 grams of carbs per day, or even less if possible. Be mindful of hidden sources of carbohydrates, such as condiments and sauces, which can add up quickly.

Increase Healthy Fat Consumption

Make sure to consume enough high-quality fats, such as nuts, extra virgin olive oil, coconut oil, and fatty fish like salmon, tuna, sardines, and mackerel. These healthy fats should make up about 70%-80% of your daily calorie intake.

Intermittent Fasting

Intermittent fasting involves alternating between periods of fasting and normal eating. This method can help you reach ketosis faster. Try the 16/8 method, which involves fasting for 16 hours and restricting your food intake to an 8-hour window. If you're new to intermittent fasting, start with a shorter fasting period and gradually increase the duration. Stay hydrated during your fast and listen to your body—if you experience negative side effects, shorten the fasting period.

Exercise

Exercising is another effective way to boost ketosis. Intense exercise, in particular, can help you reach ketosis faster. Try incorporating intense workouts at the beginning of your fast. For example, go for a long walk or do some sprinting intervals.

Avoid Common Mistakes

Be mindful of potential mistakes that can hinder your progress. Avoid overeating protein and make sure you're consuming enough healthy fats. Stay hydrated and maintain your electrolyte levels by drinking plenty of water and consuming electrolytes or electrolyte-rich foods like avocados, leafy greens, and bone broth.

Remember, combining intermittent fasting with a keto diet may not be suitable for everyone. Always consult with your healthcare provider before making any significant dietary changes, especially if you have a medical condition or are taking medications.

The downsides of combining keto and intermittent fasting

Combining keto and intermittent fasting may be a popular approach to weight loss, but it is not without its downsides. Here are some of the potential disadvantages to be aware of:

Lack of research

While both keto and intermittent fasting have been individually studied and shown to be effective for weight loss, there is a lack of rigorous research on combining the two approaches. This means that the potential benefits, effectiveness, and safety of this combined approach are not yet fully understood.

Restrictiveness

The keto diet is already a highly restrictive diet, eliminating many food groups and requiring careful planning to ensure nutritional needs are met. Adding intermittent fasting on top of this further restricts not only what you can eat but also when you can eat. This level of restriction can be challenging to stick to and may not be suitable or safe for everyone.

Potential nutritional deficiencies

The keto diet, when not carefully planned, can lead to nutritional deficiencies. Adding intermittent fasting may exacerbate this issue by further reducing the number of calories and nutrients consumed. This could result in excessive weight loss or the loss of lean muscle mass if not properly managed.

Adverse reactions

Some people may experience adverse reactions when combining keto and intermittent fasting. These could include overeating on non-fasting days, irritability, and fatigue. It may also lead to a combination of side effects from each approach, such as nausea and constipation.

Difficulty sustaining

Combining keto and intermittent fasting requires a significant level of commitment and can be challenging to maintain, especially over the long term. This is due to the restrictiveness of the diets, which can make it difficult to stick to, particularly when trying to maintain a social life and a flexible schedule.

Not suitable for everyone

While this combined approach may be beneficial for some, it is not suitable for everyone. It should be avoided by pregnant or breastfeeding women and those with a history of disordered eating. People with certain health conditions, such as diabetes, heart disease, kidney disease, or a history of eating disorders, should consult a healthcare professional before attempting this restrictive diet combination.

In conclusion, while combining keto and intermittent fasting may offer potential benefits for weight loss, it is important to carefully consider the downsides and potential risks. It is always advisable to consult a healthcare professional before making any significant dietary changes, especially when combining restrictive approaches.

What to eat on keto

The ketogenic (keto) diet is a high-fat, very low-carb way of eating. Carbohydrates are typically reduced to 20 to 50 grams per day, which forces your body to rely on fats instead of glucose for its main energy source. This metabolic process is called ketosis.

Animal Proteins

Fish and shellfish are keto-friendly. Salmon and other fish are not only carb-free but also rich in B vitamins, potassium, and selenium. Meat and poultry are also considered staple foods on the keto diet. They contain no carbs and are rich in B vitamins and minerals. Eggs are also an extremely healthy protein source on keto, with each large egg containing less than 1 gram of carbs and about 6 grams of protein.

Dairy and Dairy Alternatives

Cheese is a great fit for the keto diet, as most varieties are very low in carbs and high in fat. Plain Greek yogurt and cottage cheese are also suitable, as they are high in protein and can be eaten in moderation. Cream and half-and-half are also keto-friendly, but they should be consumed in moderation. Unsweetened plant-based milk, such as soy, almond, and coconut milk, are also good choices.

Green Leafy Vegetables

Green leafy veggies are extremely low in carbs, making them excellent for keto. They are also rich in vitamins, minerals, and antioxidants. Some keto-friendly leafy greens include lettuce, spinach, kale, collard greens, and cabbage.

High-Fat Veggies

Avocados and olives are unique among vegetables as they are fairly high in fat and low in net carbs. They also contain fiber and are good for heart health.

Other Non-Starchy Vegetables

Some other non-starchy, low-carb veggies that are suitable for the keto diet include summer squashes, peppers, cauliflower, spaghetti squash, jicama, and turnips.

Other Plant-Based Foods

Nuts and seeds are healthy, high in fat, and low in carbs. Berries are also good for keto, as they are low in carbs and high in fiber. Dark chocolate and cocoa powder are also suitable, as long as they contain a minimum of 70% cocoa solids.

Fats and Oils

Olive oil, butter, ghee, avocado oil, and coconut oil are good choices for fats and oils on the keto diet.

Drinks

Unsweetened coffee and tea are healthy, carb-free drinks that can be enjoyed on the keto diet. Unsweetened sparkling water is also a good keto-friendly alternative to soda.

How to lose weight on keto

The ketogenic, or keto, diet is a low-carb, high-fat diet that has gained popularity as a weight-loss tool. The diet involves reducing carbohydrate intake to a minimum and replacing it with fat, forcing your body to use fat from food or your own fat stores as an energy source. This process is called 'ketosis'.

To lose weight on keto, there are several steps you can take:

Reduce Carbohydrate Intake

To reach ketosis, you need to drastically reduce your carbohydrate intake. This means avoiding or heavily restricting wheat, grains, potatoes, corn, pulses, beans, milk, fruit, and sugar. For someone eating 2,000 calories a day, this means consuming a maximum of 20-50 grams of carbohydrates.

Increase Healthy Fats

On the keto diet, you replace carbohydrates with healthy fats. Avocados, olive oil, nuts, seeds, and full-fat dairy are all good sources of healthy fats.

Choose Whole Foods

Even if you're following keto, it's important to focus on consuming nutritious, whole foods. Relying on processed foods like keto desserts or convenience foods like hot dogs can slow down weight loss and are often high in calories and low in vitamins, minerals, and antioxidants.

Monitor Calorie Intake

To lose weight, you need to create a calorie deficit. While keto-friendly foods like avocados, olive oil, and nuts are high in healthy fats, they are also high in calories, so it's important not to overindulge. Use portion control and track your macronutrients through apps to ensure you're staying within a healthy calorie range.

Incorporate Physical Activity

In addition to diet, incorporating more physical activity can stimulate fat loss and benefit your health in numerous ways. Exercise helps burn calories, build muscle, and boost your metabolism.

Manage Stress and Sleep

Research shows that chronic stress and lack of sleep can negatively impact weight loss. When stressed, the body produces excess cortisol, a hormone that encourages fat storage, especially in the belly area. Lack of sleep also increases appetite. Try techniques like meditation or yoga to reduce stress and improve sleep.

Be Mindful of Snacking

While snacking on healthy foods can prevent hunger and overeating, constantly snacking on high-calorie keto foods like nuts, nut butter, or cheese may cause your weight loss to plateau. Choose lower-calorie options like non-starchy vegetables or proteins to keep you feeling full.

Be Consistent

Small, consistent changes are the key to losing and maintaining weight in a healthy way. Remember that weight loss can vary from person to person, so don't compare your journey to others. Focus on making sustainable changes that you can stick to for the long term.

While the keto diet can be an effective weight-loss tool, it may not be suitable for everyone. It is always recommended to consult with a healthcare professional before starting any new diet, especially if you have any medical issues or are taking medication.

Frequently asked questions