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Intermittent Fasting Terms

Curious about all the Intermittent Fasting "IF" terms you hear but not sure what they mean?

Intermittent fasting:   (IF) is an eating pattern that cycles between periods of fasting and eating.It doesn’t specify which foods you should eat but rather when you should eat them. Some different types are daily 16-hour fasts , 18 hour fast or fasting for 24 hours, which is also called one meal a day.

Fasting:  Fasting is just the time where you are not eating.  The word in the greek means “not to eat”.  Fasting has been a practice throughout human evolution. Ancient hunter-gatherers didn’t have supermarkets, refrigerators or food available year-round. Sometimes they couldn’t find anything to eat. So they might eat a lot at one time and not for another.

Time-Restricted Feeding

Time restricted feeding (TRF) came on the scene after intermittent fasting.  Some people say that TRF and IF are often treated as if they are one and the same, but others say there are actually some major differences between the two. With TRF, all of your eating is compressed into about a 8-hour window or 6 hour eating window.   So they call TRF if you are eating from —say from 12 p.m. to 8 p.m. The other hours, between 8 p.m. and 11:49 a.m., you don’t consume calories, although you can have calorie-less drinks, like water and black coffee. But with intermittent fasting some say it’s over 24 hours or it can be alternate-day fasting or it could be the adoption of a very low-calorie diet twice a week (5:2 fasting) and then eating normally on the other five days.  In my opinion I just say intermittent fasting and time restricted eating are the same,  but some people will argue differently!

Fasting Window: The block of time each day in which you fast and don’t eat.  Example: my fasting window is from 6pm-12noon.

Eating Window: The block of time in which you are consuming food.  Example: My eating window is from 12pm-6pm.

16:8: A popular form of intermittent fasting in which you fast for 16 hours each day, and eat in an 8 hour window. (For example, eating from 12pm-8pm each day.)

18:6: A popular form of intermittent fasting in which you fast for 18 hours each day, and eat in an 6 hour window. (For example, eating from Noon-6pm each day.)

OMAD - "One Meal A Day": A form of intermittent fasting in which you consume all of your calories for the day within one "meal." This may be one meal lasting 30 min to an hour.  Some people might only eat literally one meal either breakfast, lunch, or dinner.  Lately people say one meal a day of maybe a snack and a meal and that eating window extending over from say 2pm-6pm.  Maybe at 2pm you have a small snack and then you just eat one meal at 5:30pm.

5:2: A form of intermittent fasting developed by Dr. Michael Mosley, also known as the "Fast Diet." It mandates 5 days of normal calorie intake, with two "fasting" days of 500 calories.  I DO not recommend this diet.

ADF - "Alternate Day Fasting": A form of intermittent fasting in which days of normal eating are cycled with days of complete fasting, or severe calorie restriction. I recommend this only in one way.  I have seen huge success with this if you say eat in this example
Monday : Eat in a 6 hour window

Tuesday : Eat in an 8 hour window

Wednesday: Fast all day

Thursday: Eat in a 10 hour window

Friday: Fast all day

Autophagy: A process which occurs in the body during fasting, where your body is consuming your body’s own cells and tissues.  It’s basically eating itself.  Thee body begins using old broken proteins in the body for growth and repair.

Bullet proof Coffee: Bulletproof coffee typically refers to a concept, created by Dave Asprey, of adding fat (like grass-fed butter, coconut oil, or MCT oil) to your coffee during a fast. I believe this breaks your fast and I love the brand of coffee Bulletproof coffee.  However, it’s two different things one is the BRAND of the coffee and one is adding all of the different things like the MCT oil to now call it Bullet proof even if you don’t make it bullet proof.

"Breaking The Fast": The concept of eating or drinking calories which take the body out of the fasted state.

Extended Fast: I like to say this is anything more than 24 hours.  Like a 2 day fast, 3 day fast or 7 day fast.  ( or longer)

FMD - "Fasting Mimicking Diet": A 5 day cycle diet developed by Dr. Valter Longo, intended to mimic the effects of fasting, while still eating specifically determined nutrient-rich, plant-based low protein meals.

Insulin: A hormone produced in the pancreas  which regulates the amount of glucose in the blood. The lack of insulin causes a form of diabetes.

When you eat, your body sends a hormone released by the pancreas in response to food intake, to take sugar out of the bloodstream and put it into the body's cells. The release of insulin stops fat burning in cells.

Insulin Resistance: A state in which the body's cells become resistant to insulin, requiring the pancreas to produce more and more insulin to lower blood sugar and shuttle fat into cells. This can create a state of constant hunger and weight gain, as well as fluctuating energy levels and blood sugar swings. Insulin resistance is often involved in diabetes and weight gain.

Keto: Some people think that you only say keto when you are  reference to the "Keto" diet, in which you limit your carb intake to around 20 grams of net carbs per day.  However when you are fasting you are in ketosis.

Ketosis: A metabolic state in which the body goes from sugar burning to fat burning.  – It begins running primarily on dietary fats or body fat.

Ketones:  Ketones are chemicals your liver makes. You produce them when you don't have enough insulin in your body to turn sugar (or glucose) into energy. You need another source, so your body uses fat instead. Your liver turns this fat into ketones, a type of acid, and sends them into your bloodstream. Your muscles and other tissues can then use them for fuel. You can buy tests to check your ketone levels.  You can get there by fasting or eating a keto diet.  Many people think it’s just from a KETO diet. That isn’t true. Both ways will get you there.