The Complete Guide To Fasting

by Jason Fung

We recommend that blood sugar be checked regularly between two and four times per day, as there is the potential for low blood sugar as well as high blood sugar.

42-Hour Fasts Many clients in the IDM Program routinely skip the morning meal and have their first meal of the day around noon. This makes it easy to follow a sixteen-hour fasting regimen (see here) on regular days. There is nothing magical about eating as soon as you get up. Starting the day with just a large cup of coffee is quite acceptable. Combining this daily routine with an occasional (two to three times per week) thirty-six-hour fast results in a forty-two-hour fasting period. For example, you would eat dinner at 6 p.m. on day 1. You skip all meals on day 2 and eat your regular “breakfast” meal at noon on day 3. This gives you a total fast of forty-two hours.

Incorporating intermittent fasting (16:8 and 20:4) and heavy lifting / interval training (to preserve muscle mass and drain those glucose stores) helped me get into ketosis faster and lose fat more efficiently than using a well-formulated ketogenic diet alone. Diet alone takes about 3+ weeks to get past hunger, but fasting and exercise with keto cuts time in half.

It’s normal for bowel movements to slow down during prolonged fasting—nothing goes into the digestive system, so it makes sense that little comes out.

Discomfort from constipation occurs when your intestines are full of stool, but during an extended fast, there is little inside the colon and therefore little discomfort. This also reflects the fact that the body is recycling all the essential fats and amino acids from the breakdown of old or dysfunctional cells.

Also, if you feel unwell at any point during the fasting, you must stop. You may feel hungry, but you should not feel faint, unwell, or nauseated. This is not normal, and you should not attempt to push through.

A fourteen-day fast delivers seven times the benefit of a two-day fast but is only marginally more difficult.

Top 9 Fasting Tips 1. Drink water: Start each morning with a full eight-ounce glass of water. It will help you start your day hydrated and set the tone for drinking plenty of fluids throughout the day. 2. Stay busy: It’ll keep your mind off food. Try fasting on a busy workday. You may be too busy to remember to be hungry. 3. Drink coffee: Coffee is a mild appetite suppressant. There’s also some evidence that green tea may suppress appetite. Black tea and homemade bone broth may also help control appetite. 4. Ride the waves: Hunger comes in waves; it is not constant. When it hits, slowly drink a glass of water or a hot cup of coffee. Often by the time you’ve finished, your hunger will have passed. 5. Don’t tell people you are fasting: Most people will try to discourage you simply because they don’t understand the benefits of fasting. A close-knit support group of people who are also fasting is often beneficial, but telling everybody you know is not a good idea. 6. Give yourself one month: It takes time for your body to get used to fasting. The first few times you fast will be difficult, so be prepared. Don’t be discouraged. It gets easier. 7. Follow a nutritious diet on nonfasting days: Intermittent fasting is not an excuse to eat whatever you like. During nonfasting days, stick to a nutritious diet low in sugar and refined carbohydrates. Following a low-carbohydrate diet that’s high in healthy fats can also help your body stay in fat-burning mode and make fasting easier. 8...

Try breaking your fast with a snack or small dish to start, then wait for thirty to sixty minutes before eating your main meal.

Here are some suggestions for that first snack: ¼ to ⅓ cup macadamia nuts, almonds, walnuts, or pine nuts 1 tablespoon peanut butter or almond butter A small salad (instead of salad dressing, try cottage cheese or crème fraîche) A small bowl of raw vegetables with some olive oil and vinegar drizzled on them A bowl of vegetable soup

Tips for Breaking Your Fast with a Snack • Make sure your portion sizes are small. You will be eating a full meal shortly, so there is no need to gorge. • Take the time to chew thoroughly.

Don’t forget to drink water! Drink a tall glass of water before you break your fast

a study shows that both decaffeinated and regular coffee suppress hunger better than caffeine in water. Given its health benefits, there is no reason to limit coffee intake. Chia seeds: Chia seeds are high in soluble fiber and omega-3 fatty acids. These seeds absorb water and form a gel when soaked in liquid for thirty minutes, which may aid in appetite suppression. They can be eaten dry or made into a gel or pudding. These may be taken during a fast to help suppress hunger. Once again, while technically breaking the fast, the effect is so slight that it does not significantly detract from the benefits of the fast. The increased compliance more than compensates.

Dizziness If you experience dizziness during your fast, most likely, you’re becoming dehydrated. Preventing this requires both salt and water. Be sure to drink plenty of fluids, and in case you’re low on salt, add extra sea salt to homemade bone broth or mineral water. Another possibility is that your blood pressure is too low—

Headaches Headaches are common the first few times you fast. It is believed that they’re caused by the transition from a relatively high-salt diet to very low salt intake on fasting days. Headaches are usually temporary, and as you become accustomed to fasting, this problem often resolves itself. In the meantime, take some extra salt in the form of broth or mineral water.

Constipation This is common and to be expected. Bowel movements will typically decrease during a fast simply because there is less food intake. If you are not experiencing actual discomfort, then there’s no need to worry about decreased bowel movements. However, increasing your intake of fiber, fruits, and vegetables during the nonfasting period may help with constipation. Metamucil can also be taken during or after fasting to increase fiber and stool bulk.

Heartburn To prevent heartburn after a fast, avoid taking large meals— try to just eat normally. Avoiding lying down immediately after a meal can also help; try to stay in an upright position for at least a half hour after meals.

Muscle Cramps Low magnesium, which is particularly common in diabetics, may cause muscle cramps. You may take an over-the-counter magnesium supplement. You may also soak in Epsom salts, which are magnesium salts. Add a cup to a warm bath and soak in it for half an hour—the magnesium will be absorbed through your skin.

Similarly, exercising in the fasted state trains your muscles to burn fat.

When we deplete our glycogen through fasting, our muscles learn to become much more efficient at burning fat. The number of specialized fat-burning proteins is increased, and the breakdown of fat for energy is enhanced.

Can you exercise while fasting? Absolutely. The benefits include: 1. You can train harder due to increased adrenaline. 2. You’ll recover from a workout and build muscle faster due to increased growth hormone. 3. You’ll burn more fat due to increased fatty acid oxidation. Train harder, build muscle, burn fat. Perfect!

In this thirty-six-hour fasting regimen, you’ll fast for the entire day at least three days of the week. Unlike the twenty-four-hour fasting protocol, no meals are taken on fasting days, only fasting fluids (see here). Overall, this protocol is more effective for weight loss than the twenty-four-hour fasting protocol (here), and the longer fasting period is also better for reducing blood sugar and therefore may be better for those with prediabetes. Also, some people prefer the simplicity of fasting for the entire day, rather than eating one meal on fasting days, as on the twenty-four-hour protocol. On eating days, we recommend you follow a diet that is low in refined carbohydrates and high in natural fats. Strive to eat only whole, unprocessed foods and avoid processed or prepared foods as much as possible. In the example below, you’d fast from dinner on Sunday night until breakfast on Tuesday morning. If you finish dinner on Sunday at 7:30 p.m., then you would not eat again until breakfast on Tuesday morning at 7:30 a.m. You may consume breakfast, lunch, and dinner on nonfasting days.

In this forty-two-hour fasting regimen, you’ll fast for the entire day at least three days of the week and skip breakfast every day, regardless of whether or not you are fasting. On fasting days, you are only allowed fasting fluids (here). In the Intensive Dietary Management Program, we typically use this forty-two-hour fasting protocol for type 2 diabetes. The extended fasting period allows blood glucose and insulin more time to drop. However, if you are taking medications, you will need to consult your physician before fasting on this protocol, in order to avoid low blood sugar. While we want and expect blood sugars to drop, if you’re overmedicated, they may drop too low, at which point you may have no choice except to eat some sugar to raise it—which defeats the point of fasting. On eating days, we recommend you follow a diet that is low in refined carbohydrates and high in natural fats. Strive to eat only whole, unprocessed foods and avoid processed or prepared foods as much as possible. In the example below, you’d fast from dinner on Sunday night until lunch on Tuesday. If you finish dinner on Sunday at 7:30 p.m., then you would not resume eating until lunch on Tuesday afternoon at 1:30 p.m. On nonfasting days, you would consume lunch and dinner only, not breakfast.

This fasting protocol calls for fasting for seven to fourteen days consecutively. This means seven to fourteen days in a row without any meals or snacks. You are only allowed fasting fluids (here) during the fasting period. In the Intensive Dietary Management Program, we typically use this protocol for severe diabetes or morbid obesity. In cases where control of diabetes and/or obesity is more urgent, we often suggest starting therapy with this protocol, then transitioning to a forty-two-hour fasting protocol (here). This protocol is also useful when hitting plateaus in weight loss and after periods of weight regain, such as the holidays and vacations (such as a cruise)—and knowing that you’ll follow this protocol after a period of celebration can let you enjoy it without guilt. This is a very intensive regimen and should only be attempted with the supervision of your physician. If you are taking medications, some of them will need to be adjusted prior to beginning the fast. (See here for more information.) In this protocol, we also recommend the daily use of a general multivitamin in order to prevent micronutrient deficiency. Your physician may also want to monitor your bloodwork throughout the fast. Remember, hunger does not progress. Day 2 is typically the hardest day on this regimen: studies of the hunger hormone ghrelin show that it peaks on day 2 of extended fasting and thereafter declines. Typically, each day gets easier. Most people remark after seven days that the...

BULLETPROOF COFFEE Bulletproof coffee has become very trendy in recent years. This can be consumed once a day on fast days to help you feel satiated. It’s most helpful when consumed between the time you wake up and your regular lunch hour (if you are not eating lunch). PREP TIME: 2 minutes COOK TIME: — YIELD: 1 cup INGREDIENTS 1 cup brewed coffee 1–2 tablespoons coconut oil or MCT oil 1–2 tablespoons butter 1–2 tablespoons heavy whipping cream (at least 35% fat) DIRECTIONS 1. Add equal parts coconut oil, butter, and cream to the coffee. 2. Blend with an immersion blender until creamy.