The Ultimate Guide to Intermittent Fasting for Beginners
By: Alison Moodie
- Intermittent fasting is when you eat during a specific time period, and fast the rest of the time.
- The benefits of intermittent fasting include: weight loss; protection against chronic disease; improved brain function; and increased longevity.
- The fats in Bulletproof Coffee help you through your fast by keeping your body out of famine mode.
Fasting isn’t a new concept. For centuries, people have temporarily restricted their food intake for religious reasons. In the past few years, intermittent fasting — when you don’t eat for anywhere from 16 – 48 hours (or more) — has gained traction for its incredible effects on disease and aging.
What is intermittent fasting?
Intermittent fasting is the process of cycling in and out of periods of eating and not eating. There are several different intermittent fasting methods. One fasting diet, called the 5:2, allows you to eat normally five days a week. The other two days are so-called fasting days, where you consume just 500-600 calories. Another intermittent fasting style restricts all food for 24 hours, once or twice a week. Then there’s the one where you eat all of your daily calories within a shortened period — typically 6 to 8 hours — and fast for the remaining 14 to 16 hours. This one is known as the 16/8 diet. Bulletproof Intermittent Fasting most closely resembles this method, but with one crucial difference: you drink a cup of Bulletproof Coffee in the morning.
Health benefits of intermittent fasting
Depriving your body of food carries enormous physical and mental benefits. It makes sense from an evolutionary standpoint. For most of history, humans weren’t eating three square meals a day, plus snacks. Instead, humans evolved in situations where there wasn’t much food, and they learned to thrive when fasting. Nowadays, we don’t have to hunt for food, we spend most of our days in front of computers, and we eat whenever we want — even though our bodies aren’t adapted to this behavior.
Research shows that switching to an intermittent fasting diet expands your limits and boosts your performance in a number of ways. Here are just a few benefits:
- Boosts weight loss
- Increases energy
- Promotes cellular repair and autophagy (when your body consumes defective tissue in order to produce new parts)
- Reduces insulin resistance and protects against type 2 diabetes
- Lowers bad cholesterol
- Promotes longevity
- Protects against neurodegenerative diseases such as Alzheimer’s and Parkinson’s
- Improves memory and boosts brain function
- Makes cells more resilient
Intermittent fasting and weight loss
If you want to lose fat, intermittent fasting is the way to go. Fasting drains your body of its glucose reserves, its main energy source from food. Without glucose, you switch over to burning fat for fuel in a process called ketosis.
A 2014 study from nonprofit Salk Institute for Metabolic Studies found that adult mice who were restricted to eating within a nine- to 12-hour period gained less weight and had less fat mass than mice who ate at all hours. What’s more, time-restricted mice who were allowed free access to food on weekends looked about the same as mice who fasted seven days a week, suggesting that a brief break from fasting won’t mess with your progress.
Another study found that obese adults who followed the alternate-day fasting method (when you eat 25% of your daily calories on one day, and then eat normally the following day) lost roughly 13 pounds over an eight-week period.
Bulletproof intermittent fasting kicks it up a notch. Putting Brain Octane Oil in your Bulletproof Coffee propels you into ketosis, and keeps you there even if you have some carbs in your diet.
Intermittent fasting and the brain
As you get older, there’s less blood flow to the brain, your neurons shrink, and your brain volume declines. Intermittent fasting can boost brain health in the following ways:
Lowers risk for disease: Intermittent fasting can lower your risk for neurodegenerative diseases such as Alzheimer’s and Parkinson’s. For one, it reduces obesity and can help protect against diabetes — both increase your risk for developing Alzheimer’s.
Protects neurons and promotes autophagy: Intermittent fasting also helps the brain by protecting nerve cells from degeneration. A 2003 study found that intermittent fasting helped guard neurons in the brain from excitotoxic stress (neuronal death). It also can accelerate autophagy in your neurons — the process your body undergoes to clean out damaged cells and generate new ones. This helps your body defend itself naturally against disease.
Improves memory: Intermittent fasting improves learning and memory, another protective measure against serious neurodegenerative diseases. A 2009 study of 50 elderly adults found that three months of caloric restriction boosted memory (measured by their ability to recall words).
Eases depression: It could also help with mood disorders like depression. A 2013 literature review found that people with depression reported an improvement in mood, mental alertness, and a sense of peace when fasting.
Intermittent fasting promotes longevity
Studies show that intermittent fasting can protect against cancer, diabetes, and heart disease, helping you to live longer.
Lowers cholesterol: A 2010 study of overweight women found that intermittent fasting improved a number of risk markers for chronic disease, including lowered blood pressure, lowered cholesterol and reduced insulin resistance.
Slows down cancer: When done in tandem with chemotherapy, intermittent fasting can also slow the progression of breast cancer and skin cancer by increasing the levels of tumor-infiltrating lymphocytes — cells sent by the immune system to attack the tumor. 
Keeps cells resilient: Another way it increases your lifespan and slows aging is by manipulating mitochondrial networks. Mitochondria are the power generators in your cells — they produce most of the energy that’s needed for a cell to survive. A 2017 study from Harvard University found that fasting kept mitochondrial networks fused together. That’s what keeps the mitochondria strong and able to do their job of processing energy — crucial for longevity and vibrant aging.
How to boost your intermittent fasting results
Traditional intermittent fasting plans leave you hungry and cranky. That’s not what you need mid-morning, especially if you have a job and you need to get work done. There’s a hack for that.
Use MCT oil in the a.m.: Bulletproof intermittent fasting uses Brain Octane Oil (a form of MCT oil, a saturated fatty acid that gives your body instant energy) and grass-fed butter in your coffee to put you into mild ketosis — a metabolic state where your body burns fat for energy in the absence of carbs. In this mode, you feel more alert and less hungry, so you can power through your fast.
By keeping proteins and carbs out of the meal, you remain in the fasting state, while the fat stops your body from going into starvation mode.
Cut back on carbs: Another way to improve your results, especially when it comes to weight loss: limit the amount of carbs in your diet. If you eat a lot of carbohydrates when not fasting, your body will stockpile glucose as glycogen — meaning, it’ll take a lot longer for your body to shift into ketosis, or fat-burning mode, when you’re fasting. That’s why the Bulletproof Diet recommends eating just one serving of starch or fruit a day.
How to intermittent fast
On the Bulletproof Diet, you bypass a traditional breakfast, and eat lunch and dinner within a six-hour window, which gives you an 18-hour fast. Most people will have no problem intermittent fasting every day. Some women may need to do intermittent fasting every other day or a couple of times a week, and build up from there (more on that later). Experiment to see what works for you.
Try drinking only Bulletproof Coffee for breakfast for two weeks, then compare how you feel when you eat food for breakfast.
Here is a sample Bulletproof intermittent fasting schedule:
Step 1: Finish dinner by 8pm
Step 2: Drink Bulletproof Coffee in the morning
You can have another cup before 2:00 PM if you get hungry.
Step 2.5: Work out (optional)
This isn’t necessary for weight loss or intermittent fasting. But if you’re going to work out, high-intensity weight training is the best option. Small amounts of hard exercise are better than longer workouts. Exercise just before breaking your fast.
Step 3: Eat a high-fat, moderate protein, low-carb lunch at 2pm.
Step 4: Don’t worry about counting calories, but try not to snack between meals. Save your carbs for dinner, and finish eating by 8pm.
Intermittent fasting and women
Typical intermittent fasting can sometimes cause problems for women, including sleeplessness, anxiety, hormone imbalance, and irregular periods. That’s because women have evolved to remain fertile and reproduce. When a woman restricts calories and healthy fats, her body gets stressed and goes into famine mode. Her fertility stops until her caloric intake increases to levels that can support reproduction.
But that doesn’t mean women shouldn’t fast. Some women feel better when they do Bulletproof intermittent fasting instead. The fats in Bulletproof Coffee fuel your brain so you don’t get the same stress response.
If you wake up between 3am and 5am and can’t go back to sleep, you’re doing too much fasting. It means your body is under stress and is releasing too much adrenaline and cortisol.
On non-fasting days, add grass-fed collagen to your Bulletproof Coffee, and eat some protein and fat, like poached eggs or smoked salmon and avocado, in the morning. Cut down your fasting to once or twice a week, and build up from there. Experiment and find what works for you.
Keep in mind that you shouldn’t do any type of fasting if you’re pregnant or breastfeeding, unless your doctor gives you the okay.
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