Intermittent Fasting isn’t New
There are lots of strategies I use with my female patients, but none more powerful than intermittent fasting. For many women this is the magic bullet that allows them to gain back their former selves.Cynthia Thurlow, TED Talk
While intermittent fasting seems like the latest trend, it’s actually been around for centuries. Fasting as a practice has been used since the beginning of time for medical and religious purposes. It’s gained popularity recently for its dramatic weight loss effects. Even mainstream medical professionals are endorsing fasting as a regular practice.
Before you blame yourself, let’s talk about how you ended up in the position. The truth is, the low fat, high snack narrative was ill-advised. To put it simply, snacking didn’t exist when my mother was a child. She was offered two or three meals a day, with nothing but water between. In the course of one generation, all day eating became common practice.
- Breakfast is the most important meal of the day
- Hunger throughout the day is normal
- Three meals a day is ideal
- Snacking is a healthy behavior
Frequent eating crushed our natural ability to use fat as a steady, long-burning fuel. Instead we started relying on glucose (sugar) as our main source of fuel.
Our ancestors survived in the fasted state much of their lives. They didn’t eat three meals and a day and certainly didn’t snack all day long on top of meals.
Over time, with constant eating and insulin stimulation, we’ve lost the ability to switch back and forth easily. Modern humans live in a constant fed state. Constant insulin stimulation causes oxidative stress, metabolic dysfunction, and eventually insulin resistance. Not to mention arguments, emotional outbursts, and other “hangry” behavior.
We are designed to move easily between fat-fueled and sugar/glucose fueled states. Unfortunately, over time, we’ve lost that metabolic flexibility.
Sugar Roller Coaster
Sugar is a fast-burning fuel, like kindling on a fire. It gives a burst of energy and then it’s gone, leaving you feeling tired, grumpy, and mentally sluggish. With glucose as a primary fuel source, sugar burners are easy to identify. They often suffer from…
- Frequently hunger
- Impatient, urgent need to eat
- Brain fog
- Dips in energy levels
- Difficulty losing weight
Unlike sugar burners, Fat burners are metabolically flexible. They use stored fat as a steady source of fuel. This is a near-endless supply of clean-burning, steady fuel. They rarely experience hunger, brain fog, or hunger tantrums. What they experience instead…
- Weight loss
- Boost in mental clarity
- Steady energy
- Improved sleep
- Lower blood glucose
- Lower insulin
- Lower blood pressure
- Lower cancer risk
- Lower Alzheimer’s risk
The also experience increased
- Insulin sensitivity
- Lipolysis and free fatty acid mobilization
- Cellular fat oxidation
- Human Growth Hormone
- Autophagy (cell cleaning)
- Fat burning!
While fasting produces dramatic health benefits it also has some compelling lifestyle advantages. It’s amazing the amount of stress that’s relieved by not having to worry about eating from daylight to dusk.
- Saves time (one less meal to plan each day)
- Saves money (same)
- Makes traveling easier
- Makes you a nicer, less ‘hangry’ person
- More flexible with your meal schedule
16/8 Eating Schedule
As the lazy biohacker, I am, I’m not going through the multitude of fasting options available. There are many ways to organize your feeding and fasting windows. That said, the VAST majority of you will likely find a simple 16/8 schedule easiest to adopt. You can gradually adjust to this schedule by shifting your eating times by 30 mins or an hour each day.
Combined with a Keto Diet
Intermittent fasting is a natural complement to a Keto diet. When eating Keto, you’re in a pseudo fasted state more often. By avoiding carbs and focusing on fat and protein you don’t provoke insulin as often or as dramatically as you would eating carbs. Combining Keto and intermittent fasting is a nice one-two punch for weight loss. Read more about the Keto Diet.
Most people practicing intermittent fasting eat one or two meals a day. They don’t start breakfast at noon and squeeze lunch and dinner in before 8 pm. While one meal a day isn’t realistic for everyone, two meals a day is reasonable.
This results in a calorie deficit which isn’t a bad thing. While you’re adapting, don’t obsess about this point. Your hunger will naturally lessen over time and make this adjustment easier.
No more Snacking
Anytime we eat, anything, there is an insulin response. The magnitude of that response depends on what, and how much you eat. Once your hunger lessens, you should eliminate snacks between meals.
Overall, we should increase fasted windows between meals as well. Remember, our body needs time to digest and process the food. Constantly feeding our body interrupts that natural process. The good news is if you will stop feeling hungry between meals once you’re fat-adapted which makes this easier.
While you’re fasting, you can and should drink water, unsweetened tea, coffee, and broths. I also usually drink electrolytes. Ideally you wouldn’t have any sweeteners or cream in these drinks. If you do add something, make sure it’s heavy cream (full fat) or a keto-friendly sweetener.
I was once a loyal breakfast club member. Believe me, I was beating the “breakfast is the most important meal of the day”, drum harder than anyone. Now I still enjoy breakfast but usually at dinnertime.
Bulletproof coffee is another hack that helps people who wake up hungry. Some would argue that the butter breaks a fast, but fat has a negligible impact on insulin. If it helps you adapt to burning fat for fuel and curbs hunger, it’s totally fine.
Favorite Books & Experts on Intermittent Fasting
- Obesity Code by Sr. Jason Fung, @drjasonfung
- Ted talk, Cynthia Thurlow, @cynthia_thurlow_
- Healthy Keto and Intermittent Fasting by Dr. Eric Berg, @drericberg
- Good General Overview
Not Safe for Everyone
You should always consult with your physician before adopting or changing your diet. Especially for these groups, for whom intermittent fasting may not be a safe option.
- Brittle or uncontrolled diabetic
- Child or adolescent
- History of kidney or renal issues
- History of a disordered relationship with food
- Low body mass index
- Pregnant or nursing
When we eat, the pancreases releases insulin. The amount of insulin depends on what you eat. The more carbs you eat, the more insulin is released. Insulin’s job is to escort the sugar into the muscle tissue and liver. When those stores are full, insulin stores the rest of the glucose as fat.