Intermittent Fasting Plus Keto for Weight Loss

Many health-conscious people follow intermittent fasting or a Keto diet for weight loss and to control certain health conditions. While both methods have their own benefits, many people may wonder if it's safe and effective to combine intermittent fasting and the Keto diet.

A ketogenic diet refers to cutting carbohydrates and fuelling the body with fat. This approach helps you to burn fat more effectively. Intermittent fasting controls your eating timings and thus aids in your weight loss. Combining these two eating strategies may prove beneficial for weight loss and metabolic health, but you need to know how to do so efficiently.

Let us understand these two diet methods in detail and learn if pairing them is safe and effective.

Intermittent Fasting

Intermittent fasting (IF) is a diet strategy which permits you to plan when to eat. Intermittent fasting includes calorie restriction or fasting and normal food eating during a specific time. This fasting may also help to reduce inflammation and improve brain functioning and blood sugar control.

One of the most popular methods of IF is 5:2 which means five days of normal eating and two days of extremely low-calorie eating. Another way of IF includes not eating for a 24-hour period or time-restricted eating (TRE) like only for eight hours and fasting for 16 hours each day.

Other most commonly followed methods in IF are 18:6, 20:4 and alternate-day fasting. The period when you don't eat or drink (besides water or other calorie-free drinks) is termed the fasting window, while the rest is termed the eating window. This diet approach allows you to choose to fast during the mornings and eat later in the day or vice versa, depending on your lifestyle. If you wish to follow IF for weight loss or get healthier, it is important that you eat only healthy meals and exclude fast food and sugary and highly processed foods.

Keto Diet

The ketogenic (Keto) diet refers to a high-fat, moderate-protein and very low-carbohydrates eating method. This diet excludes the consumption of carbohydrates and prioritizes eating fats. The aim of a typical Keto diet is to transition your body from one that burns carbohydrates to one that relies on fat for energy. This process is called ketosis and may lead to quick weight loss.

Through this diet, carbohydrate consumption is reduced to 20 to 50 grams per day which force the body to rely on fats as the energy source. Apart from weight loss, the Keto diet has been used for many years to treat epilepsy. Moreover, the Keto diet may reduce blood sugar, lower triglyceride levels and thereby minimise the risk of developing heart disease. It is also believed that the Keto diet may help in improvising the symptoms of Alzheimer's disease.

One of the advantages of the Keto diet is that it allows you to eat high-fat foods like butter, bacon, cream and nuts. By consuming fats you might stay away from the hunger pangs as fat‑rich foods keep you full for a long time.

Combining Keto Diet and Intermittent Fasting for Weight Loss

You can combine the Keto diet and intermittent fasting by putting in place an eight-hour eating window and ensuring that you stick to the required amount of carbohydrates, protein and fat distributions to remain in the state of ketosis.

Both of these diet approaches encourage your body to use fat for energy rather than glucose. Thus, combining them may boost weight loss. Due to IF, you eliminate at least one meal from your day and this creates a calorie deficit which is a key component of weight loss. Precaution must be taken that you compensate the body with more healthy food during the eating window. Replacing carbohydrates with fats when you are on a Keto diet may decrease your appetite. This may help you with intermittent fasting as well.

Foods Allowed on Keto Intermittent Fasting

Foods which have zero or low carbohydrates can be included in this combined eating approach. You can consume −

  • Eggs

  • Oil

  • Unprocessed meat like beef, pork, lamb and poultry

  • High-fat fish such as salmon, mackerel and sardines

  • Butter and other full-fat dairy products

  • Nuts like brazil, macadamia and pecan

  • Green and leafy vegetables

  • Berries but in moderation

One must ensure that these foods should be consumed in the right amount.

Food Not Allowed on Keto Intermittent Fasting

All foods containing 10 grams or more of carbohydrates should be avoided in this dietary approach. You cannot consume −

  • Grains and starches like wheat, rice, rye, corn, quinoa, buckwheat and bulgur

  • Grain products like pasta, bread, cereals, oatmeal, muesli, pizza and pastries

  • Legumes such as beans, chickpeas, lentils and peas

  • Fruits

  • Root vegetables like potato, sweet potato, yam and parsnip

  • Sugar and sweetened foods like sauces, juice and soda

Tips to start an Intermittent Fasting Keto Diet

Healthcare experts may not advise people to start Keto and IF at the same time as it could be a huge shock to the body. It is thus recommended to start with Keto and after a couple of weeks to months (varying from person to person) switch to IF. Additionally, it's important to choose the correct timing for the fast. For some people not eating overnight for 12 to 16 hours may be a natural habit, but some others may find it difficult.

Begin with delaying breakfast for an hour or so and then slowly extend the time. Thus, your body will get accustomed to going without eating for a longer time. Once the body is adjusted to the new eating pattern, you can reintroduce breakfast earlier in the day and extend the overnight fasting time.

Ideally in a Keto-IF, try to schedule your breakfast at 11 am, lunch at 3 pm and dinner at 6 pm. You can have dessert usually before 7 pm if you feel hungry. Avoid eating or drinking (except water) anything post 7 pm. The length of time to stay on Keto-IF should be no more than six months. You can then transition to a more low-carbohydrate diet.


Pregnant or breastfeeding women should avoid intermittent fasting. Also, people with health conditions like diabetes, gastrointestinal disorders or heart disease should consult their doctor before adopting this dietary approach. Some people may also experience adverse reactions like overeating on non-fasting days, fatigue or irritability.

If you are taking any prescribed medicines for blood pressure or any other health condition, it may be unsafe for you to go on Keto-IF. People who have sleeping problems, are under 18 years or have a history of disordered eating should also avoid going for a Keto-IF.


Intermittent fasting and a Keto diet can promote the use of fats and ketones for energy and you may naturally end up intermittent fasting while on a Keto diet. Although combining IF and Keto diet may augment each other's effectiveness, combining them for better results may vary from person to person. Both of these diet strategies can help in weight loss but may also lead to electrolyte imbalance. Hence, one must stay hydrated.