One potential disadvantage of this schedule is that because you typically cut out a meal or two out of your day, it becomes more difficult to get the same number of calories in during the week. Put simply, it's tough to teach yourself to eat bigger meals on a consistent basis. The result is that many people who try this style of intermittent fasting end up losing weight. That can be a good thing or a bad thing, depending on your goals.
IF makes intuitive sense. The food we eat is broken down by enzymes in our gut and eventually ends up as molecules in our bloodstream. Carbohydrates, particularly sugars and refined grains (think white flours and rice), are quickly broken down into sugar, which our cells use for energy. If our cells don’t use it all, we store it in our fat cells as, well, fat. But sugar can only enter our cells with insulin, a hormone made in the pancreas. Insulin brings sugar into the fat cells and keeps it there.
This fasting process will not only activate autophagy in your cells, it will also increase your ketones much more quickly than if you were just eating a standard ketogenic diet. If you start implementing intermittent fasting and activities (like walking, cycling, or lifting weights) together, you can raise ketone levels and increase autophagy more than you would with intermittent fasting alone. This suggests that intermittent fasting would be a great addition to your life, but it is important to be familiar with the negative symptoms that can arise before you start.
Although some of the intermittent fasting methods online seem more intense than others (some can last upwards of 48 hours), the beauty of intermittent fasting is that you get to choose and experiment with how long you fast. This not only allows you to determine how intermittent fasting can fit in within your lifestyle, but to discover the fasting sweet spot that helps you feel best physically.
Intermittent fasting is using the same reasoning – instead of using the fats we are eating to gain energy, we are using our stored fat. That being said, you might think it’s great – you can just fast and lose more weight. You have to take into account that later on, you will need to eat extra fat in order to hit your daily macros (the most important thing). If you’re overeating on fats here, you will store the excess.
Some people believe that IF has worked for them simply because the limited eating window naturally helps them reduce the amount of calories they consume. For instance, instead of eating three meals and two snacks, they might find that they only have time for two meals and one snack. They become more mindful about the kinds of food they consume and tend to stay way from processed carbs, unhealthy fat, and empty calories.
In this example, lunch on Monday is your last meal of the day. You then fast until lunch on Tuesday. This schedule has the advantage of allowing you to eat everyday of the week while still reaping the benefits of fasting for 24 hours. It's also less likely that you'll lose weight because you are only cutting out two meals per week. So, if you're looking to bulk up or keep weight on, then this is a great option.

The biggest concern most people have is that Intermittent Fasting will lead to lower energy, focus, and the “holy crap I am hungry” feeling during the fasting period and ruin them. People are concerned that they will spend all morning being miserable because they haven’t consumed any food, and thus will be miserable at work and ineffective at whatever task it is they are working on.
What if we told you that the answer to losing weight, improving body composition, and feeling better isn’t about dieting, but instead skipping meals every once in a while? For some, intermittent fasting, or going a longer period of time — usually between 14 and 36 hours — with few to no calories, can be a lot easier than you may think. And the benefits might be worth it. If you think about it, all of us “fast” every single day — we just call it sleeping. Intermittent fasting just means extending that fasting period, and being a bit more conscious of your eating schedule overall. But is it right for you? And which method is best?
If you think you may have a medical emergency, call your healthcare provider or 911 immediately. Any mention of products or services is not meant as a guarantee, endorsement, or recommendation of the products, services, or companies. Reliance on any information provided is solely at your own risk. Please discuss any options with your healthcare provider.
Is intermittent fasting safe? Remember that you’re only supposed to fast for twelve to sixteen hours and not for days at a time. You’ve still got plenty of time to enjoy a satisfying and healthy diet. Of course, some older women may need to eat frequently because of metabolic disorders or the instructions on prescriptions. In that case, you should discuss your eating habits with your medical provider before making any changes.
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Black coffee won't break your fast or take you out of ketosis. In fact, according to a report published in the Journal of Basic and Clinical Physiology and Pharmacology in 2017, caffeine may even increase your metabolism, which will help promote weight loss. Black coffee also helps curb your appetite, which can make getting through your morning fast much more manageable.
While it’s not technically fasting, some doctors have reported intermittent fasting benefits by allowing such easy-to-digest food as whole fruit during the fasting window. Modifications like these can still give your digestive and metabolic system a needed rest. For example, “Fit for Life” was a popular weight loss book that suggested eating only fruit after supper and before lunch.

I’ve read several places that adding gelatin or collagen to coffee breaks the fast, but I don’t understand why since there are no carbs, only protein, and fewer than 50 calories per tablespoon. Have you tested this? It would be great to be able to add protein to my morning coffee so I would love to know. Would also love to know if one tablespoon of coconut cream affects ketones and glucose.


This process can be used as a way to get you into ketosis more quickly, so you can transition gracefully into a ketogenic lifestyle or as a way to stimulate autophagy and fat loss. If you can’t go without fat for the full 3 day fast — it’s okay — you will still illicit many of the benefits of fasting by limiting your protein and carbohydrate intake.
You’ll spike your blood sugar when you eat. If you’re fasting on a high-carb diet and you’ve powered through the cravings and lack of energy from low blood sugar, there’s a good chance you’ll eat a ton of carbs when you feast. You want to eat big meals when you fast to make sure you’re getting enough calories, but all those excess carbs in one go will spike your blood sugar in the opposite direction, from low to high.[14] High blood sugar causes fatigue and lack of focus. That raging hunger will also cause you to binge unnecessarily, and whatever carbs you don’t use will get stored as fat.

Surprisingly, since I've started intermittent fasting I've increased muscle mass (up 10 pounds from 205 to 215), decreased body fat (down 3% from 14% to 11%), increased explosiveness (set a personal best with a clean and jerk of 253 pounds a few months back), and decreased the amount of time I've spent training (down from 7.5 hours per week to 2.5 hours per week).
IF makes intuitive sense. The food we eat is broken down by enzymes in our gut and eventually ends up as molecules in our bloodstream. Carbohydrates, particularly sugars and refined grains (think white flours and rice), are quickly broken down into sugar, which our cells use for energy. If our cells don’t use it all, we store it in our fat cells as, well, fat. But sugar can only enter our cells with insulin, a hormone made in the pancreas. Insulin brings sugar into the fat cells and keeps it there.
Cons: Going 24 hours without any calories may be too difficult for some — especially at first. Many people struggle with going extended periods of time with no food, citing annoying symptoms including headaches, fatigue, or feeling cranky or anxious (though these side effects can dimish over time). The long fasting period can also make it more tempting to binge after a fast. This can be easily fixed… but it takes a lot of self-control, which some people lack.
I’m 63 years old and I have been following a daily 19 hour protocol called Fast 5, fast5.org for two years. I eat lunch at 3pm and dinner at 7pm close my eating window at 8pm. I’ve lost 43 lbs and kept it off, feel great and I am no longer pre diabetic. I eat what I want and don’t track anything. I belong to a Facebook Intermittent fasting group called Fast Club and would to have you check it out. Fasting is free and it works!
I am a 65-year-old male who started IF seven weeks ago. I only eat between noon and 8pm. I am obese, but losing about a pound a week so far. Notably, except for time, I have not changed what I eat at all. My diet was never terrible or great, and now it is the same, a mix of raw fruit sometimes and a donut another time. But I only eat it during the appointed hours. Remarkably, I do not feel hungry. I used to eat comfort breakfasts like pancakes or waffles, and I thought I would miss them. But no, I truly am not hungry in the mornings. I often delay lunch, but I still stop eating at 8. That alone probably has cut many calories of desserts. Bottom line: works for me so far.
Not only that, but growth hormone is increased during fasted states (both during sleep [5]and after a period of fasting). Combine this  increased growth hormone secretion:[6], the decrease in insulin production (and thus increase in insulin sensitivity [7]), and you’re essentially priming your body for muscle growth and fat loss with intermittent fasting.
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