by Jason Fung, MD, with Jimmy Moore
Adam and Danette recommended a documentary about fasting that was by the same author. We weren’t able to get it from the library but the book was available, so that is why I read it. It is causing a paradigm shift for me because I always thought going on a “starvation” diet would cause your metabolism to drop and set you up for a lifetime of gaining weight despite hardly eating anything. Well, it turns out low-calorie diets do just that – but fasting actually raises your metabolism. Fasting also lowers your blood sugar and prevents Type 2 diabetes, it cleans out dead or sick cells (autophagy) and could prevent cancer and Alzheimer’s. Learned so much from this book! Thanks, Adam and Danette! What I’ve decided:
- I need to do a 12-hour fast every day, which means no more snacking after dinner;
- We need to try and eat our biggest meal at noon rather than evening. There was a study done comparing women who ate 1400 calories/day but one group ate their big meal at noon and another group ate it at night. The group who ate it at night lost very little weight. The group that ate their big meal at noon lost a lot of weight.
- Eat only at the table. Stop eating in front of the TV after dinner.
Here are some good quotes:
In the Christian tradition, fasting and prayer are often methods of cleansing and renewing the soul. Symbolically, believers empty their souls so that they may be ready to receive God. Fasting is not so much about self-denial but about a reaching for spirituality and being able to commune with God and hear his voice. By fasting, you put your body under submission to the Holy Spirit, humble your soul before the presence of God, and prepare yourself to hear the voice of God. (from page 65)
Suppose you normally eat 2000 calories a day and cut back to only 1500. Your body cannot run a deficit indefinitely–it will eventually run out of fat to burn–so it plans ahead and decreases your energy expenditure. The end result is a decreased BMR [basal metabolic rate]. This had been proven repeatedly by experiments over the last century, and we’ll talk about it in more detail in Chapter 5. Because of this well-known “starvation mode” effect of daily caloric restriction, many people assume that fasting will result in a similar but more severe decrease in BMR.
Luckily, this does not happen….
In fact, metabolism revs up, not down, during fasting. This makes sense from a survival standpoint. If we do not eat, our bodies use our stored energy as fuel so that we can find more food. Humans have not evolved to require three meals a day, every day. (from page 73)
A study comparing fasting and bariatric surgery revealed that fasting is perhaps even more beneficial in the treatment of type 2 diabetes. In a head-to-head comparison, fasting lowered both body weight and blood sugar better than bariatric surgery. (from page 137)
There are really only two methods of getting the toxic glucose overload out of the body. First, you need to stop puting glucose into the body. You can achieve this weith very low carbohydrate diets or ketogenic diets. Indeed, many people have reversed their diabetes by following such diets. Fasting also eliminates carbohydrates–and all other foods, for that matter.
Second, your body needs to burn off the excess glucose. Fasting is again an obvious solution. Your body requires energy just to keep all the vital organs, such as the heart, lunds, liver, and kidneys, working. Your brain in particular requires substantial energy to function properly, even during sleep. During fasting, no new glucose is coming in, so your body has no choice but to use up the stored glucose.
At its core, type 2 diabetes is a disease of excessive glucose, in our blood but also in our bodies. If you don’t eat, your blood sugar level will come down. Once your blood sugars are consistently in the normal range, you will no longer be considered diabetic. Presto! Diabetes reversed. Mischief managed. (from page 139)
If you are on medications for type 2 diabetes or any other conditions, then it is imperative that you speak with you physician before embarking on the fasting journey. Most diabetic medications work to lower blood sugar based on your current diet. If you change your diet without adjusting your medications, then there is a real risk of having low blood sugar, which is extremely dangerous. (from page 140)
The most obvious benefits of fasting are that it helps with weight loss and type 2 diabetes, but there are many other benefits, including autophagy (a cellular cleansing process), lipolysis (fat-burning), anti-aging effects, and neurological benefits. In other words, fasting can benefit your brain and help you body stay younger….
Mammals generally respond to severe caloric deprivation by reducin organ size, with two prominent exceptions: the brain and, in males, the testicles….
…So what actually happens during caloric deprivation is that the brain maintains or even boosts its abilities. The best-selling novel (sic) Unbroken, by Laura Hillenbrand, describes the experiences of American prisoners of war in Japan during World War II. During their extreme starvation, the prisoners experienced some astonishing mental clarity that they themselves understood was due to the effect of starvation. One man was able to learn Norwegian in just under a week. Another described “reading” entire books from memory. (from page 147-148)
Increased levels of glucose, insulin, and proteins all turn off autophagy. And it doesn’t take much….This is why the strongest stimulus to autophagy currently known is fasting, and why fasting alone, unique among diets, stimulates autophagy–simple caloric restriction or dieting isn’t enough. By eating constantly, from the time we wake up to the time we sleep, we prevent the activation of autophagy’s cleansing pathways. Simply put, fasting cleanses the body of unhealthy or unnecessary cellular debris. (This is an argument for fasting as a prevention of Alzheimer’s and cancer, from pages 152-153.)
…The scientific community has long known that eating less cholesterol does not lower blood cholesterol. Our liver generates 80 percent of the cholesterol found in the blood, so eating less cholesterol makes little or no difference. By the same token, eating more cholesterol does not raise blood cholesterol significantly. If we eat less dietary cholesterol, our liver simply compensates by creating more, so the net effect is negligible. Furthermore, it’s not the cholesterol particle itself that’s cause for concern-remember, that’s identical in both LDL and HDL. It’s instead the lipoproteins carried along with the cholesterol particle that determine whether it’s good or bad. Reducing the cholesterol in our foods makes little or no physiological difference, a fact that was proven long ago. (from pages 158-159)
The only reliable way to reduce LDL levels is to reduce the liver’s production of it. In fact, studies prove that seventy days of alternate-day fasting could reduce LDL by 25 percent. This is far in excess of what can be achieved with almost any other diet and about half of the effect achieved with a statin medication, one of the most powerful cholesterol-reducing medications available. Triglyceride levels drop by 3 percent, similar to what can be achieved with a very low carbohydrate diet or medication. Not bad for an all-natural, cost-free dietary intervention.
Plus, whereas statins carry the risk of diabetes and Alzheimer’s disease, fasting reduces body weight, preserves fat-free mass, and decreases waist circumference. In addition, fasting preserves HDL, unlike low-fat diets, which tend to decrease both LDL and HDL. Overall, fasting produces significant improvements in multiple cardiac risk factors… (from page 162 and 163)
Here’s the simplest way to break associations between food and anything else: Eat only at the table. No eating at your computer station. No eating in the car. No eating on the couch. No eating in bed. No eating in the lecture hall. No eating at the ball game. Try to avoid mindless eating–every meal should be enjoyed as a meal, not as something eaten while watching a movie. In this way, food becomes associated only with the kitchen and the table. (from page 171)
Aspirin is commonly used as a blood-thinner in people with cardiovascular disease. One common side effect is gastritis–the irritation of the lining of the stomach. In severe cases, it may cause ulcers to form in the stomach and small intestine. Aspirin is often taken with food to lessen the risk of these complications. Many aspirin tablets are now coated with a protective film to protect the lining of the stomach, but the risk of gastritis and ulcers is only reduced, not eliminated. Taking aspirin without food raises the risk of stomach irritation. (from page 184)
Daily twelve-hour fasting introduces a period of very low insulin levels during the day. This prevents the development of insulin resistance, making the twelve-hour fast a powerful preventative weapon against obesity. In fact, the combination of whole foods, lower-carbohydrate diets, less added sugars, and a daily twelve-hour fast was enough to prevent most Americans in the 1950s and 1960s from developing obesity–even though they still ate plenty of white bread and jam, and whole-wheat bread was rare and whole-wheat pasta unheard of.
But while a daily twelve-hour fast may be a great preventative strategy, it may not be powerful enough to reverse weight gain. Slightly longer fasting periods are often required for that. (From page 203 describing 12-hour fasts which are from 7:00 p.m. to 7:00 a.m., for example.)
16-Hour Fasts
This regimen incorporates a sixteen-hour period of fasting into your daily meal schedule. For examle, you might fast from 7 p.m. to 11 a.m. daily. You could also say that you have an eight-hour eating window every day. For that reason, it is sometimes called time-restricted eating. On this schedule, most people skip the morning meal every day. But how may meals you eat within that eight-hour window is your choice. Some people choose to eat two meals during that window and others eat three….
The daily sixteen-hour fast certainly has more power than the daily twelve-hour fast, but it should be combined with a low-carbohydrate diet for the best effect. Weight loss on this regimen tends to be slow and steady. (from pages 203 and 204)
…In a 2013 study, two groups of overweight women were randomly assigned to eat a large breakfast or a large dinner. both ate 1400 calories per day; only the timing of the largest meal was changed.
The breakfast group lost far more weight than the dinner group. Why? Despite following similar diets and eating about the same amount, the dinner group had a much larger overall rise in insulin….
Weight gain is driven by insulin, and the higher insulin response in the evening was translating into more weight gain for the dinner group.
…Eating the largest meal in the evening seems to cause a much larger rise in insulin than eating earlier. (from pages 205 and 206)
Timing the Largest Meal of the Day
…Eating late at night is also a poor strategy. Hunger is maximally stimulated at approximately 7:50 p.m. At this time, insulin is maximally stimulated by food, which means that the same amount of food results in higher insulin levels. This higher insulin level will naturally drive weight gain.
…So the optimal strategy seems to be eating he largest meal in the midday, sometime between noon and 3:00 p.m. and only a small amount in the evening hours. Interestingly, this is the traditional Mediterranean eating pattern. They eat a large lunch, followed by a siesta in the afternoon, and then have a small, almost snack-sized dinner. While we often think of the Mediterranean diet as healthy due to the type of foods in it, the timing of meals in the Mediterranean may also play a role. (from page 208)
To help prevent problems in the post-fast refeeding period [after an extended fast–any fast lasting longer than 42 hours], there are two steps we recommend:
1. Do not make an extended fast a water-only fast. Drinking homemade bone broth provides phosphorus and other proteins and electrolytes, which reduces the changes of developing refeeding syndrome. And to prevent vitamin deficiency, take a daily multivitamin.
2. Do all your usual activities, especially your exercise program, during your fast. This helps to maintain your muscles and bones. (from pages 232 and 233)
Top 9 Fasting Tips
1. Drink water: Start each morning with a full eight-ounce glass of water…
2. Stay busy: It’ll keep your mind off food…
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…
5. Don’t tell people you are fasting.
6. Give yourself one month…
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. Don’t binge: After your fast, pretend it never happened. Eat normally (and nutritiously–see #7), as if you had never fasted.
9. Fit fasting into your own life…Don’t limit yourself socially because you’re fasting. There will be times during which it’s impossible to fast, such as vacations, holidays, and weddings. Do not try to force fasting into these celebrations. These occasions are times to relax and enjoy. (from pages 236 and 237)
…During longer fasts, many people notice that their hunger completely disappears by the second or third day.
There are some drinks or spices allowed on fasts that can help suppress hunger. Here are my top five natural appetite suppressants:
Water: Start your day with a full glass of cold water. Staying hydrated helps prevent hunger…
Green tea: Full of antioxidants and polyphenols, green tea is a great aid for dieters. The powerful antioxidants may help stimulate metabolism and weight loss.
Cinnamon: Cinnamon has been shown to slow gastric emptying and may help suppress hunger. It may also help lower blood sugar and therefore is useful in weight loss. Cinnamon may be added to all teas and coffees for a delicious change of pace.
Coffee: While many assume that it is the caffeine in coffee that suppresses hunger, studies show that this effect is more likely related to antioxidants–although caffeine may raise your metabolism, further boosting fat-burning. But a study shows 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… (from pages 239 and 240)
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. Alternatively, you may look for magnesium oil, which also allows magnesium to be absorbed through the skin. (from page 241)
However, during the period when you are adjusting to the change from burning sugar to burning fat, you may notice a decrease in your athletic performance. This lasts approximately two weeks. as you deplete the body of sugar, your muscles need time to adapt to using fat. Your energy, muscle strength, and overall exercise capacity will go down, but they will recover. This process is sometimes called keto-adaptation. Very low carb diets, ketogenic diets, and training in the fasted state may all have benefits in training our muscles to burn fat, but your muscles do need time to adapt. (from pages 244 and 245)