What is intermittent fasting

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Intermittent fasting has been popularized for several years now. Some of the claims are that intermittent fasting will aim to help weight loss and give the user an overall healthier and energetic feeling. Longevity has also been linked to people that use fasting on a regular basis. 

There are a few different methods that one can use to gain these benefits and use intermittent fasting to their advantage.

16:8 Diet 

In the 16:8 version of intermittent fasting, you’ll restrict your eating to 8 hours of the day and be fasted for 16 hours; for example, one will stop consuming food at 10 pm and won't ingest anything with calories till 2 pm the next day. From 2 pm till 10 pm the user will consume their caloric goal. The caloric goal would be the same as a regular diet. If you were looking to lose weight your caloric needs would be 500 calories less than your maintenance level calories.

Evidence of the 16:8 diet working

*Nutrition and Healthy Aging* published a 12-week trial, 23 obese adults participated in the time-restricted eating. These subjects were eating whatever they wanted in an 8-hour window. By the end, researches found that the participants ate 350 calories less per day than the control groups. This study shows that even without tracking calories, intermittent fasting was a good way for people to consume fewer calories a day. If you apply the 16:8 diet with tracked calories, you will enhance your fat loss even more than the study showed.


This method involves fasting for 24 hours, once or twice a week. Following the 24 hours fast, the individual would meet 2 days worth of their caloric maintenance calorie goal on the feeding day.

The 5:2 diet

With this method, you consume only 500–600 calories on two non-consecutive days of the week. Eating normally the other 5 days. For these 5 days when your calories are not restricted, you would consume close to your maintenance level calories. At the end of the week, the user will still be in a caloric deficit, which will aid in fat loss.


Intermittent fasting has been shown to significantly reduce inflammation. Large amounts of inflammation are the cause of many chronic diseases that we face today including Alzheimer’s, dementia, obesity, diabetes, and more. There are many methods for how intermittent fasting reduces inflammation.

Autophagy — Autophagy is when the body destroys old or damaged cells. Think of it like cleaning off the rust and cleansing itself. It’s a way for the body to repair itself. If old or damaged cells remain in the body, they create inflammation. Intermittent fasting stimulates autophagy, helping the body to cleanse itself from old and damaged cells, thereby reducing inflammation. Your body recycles unused cells so that new stronger cells can be formed.

Ketones —  Ketones (chemically known as ketone bodies) are by-products of the breakdown of fatty acids. During fasting, the body uses sugar stores up and has to turn to fat for fuel. When fats get broken down it creates ketones. One of the most abundant ketones, Beta-hydroxybutyrate, actually blocks part of the immune system responsible for regulating inflammatory disorders like arthritis and even Alzheimer’s. You also get the benefit of burning more fat while intermittent fasting due to the increase of ketones in the body.

Insulin Sensitivity — Fasting has been shown to help resolve insulin resistance. When the body becomes resistant to insulin, insulin and glucose build up in the blood and create inflammation. Intermittent fasting allows your body to take a break. Since there is no food to digest and your body uses up all it’s sugar stores rather than using the food you ingest and insulin levels begin to drop, this allows the body to re-sensitize to insulin again.

Human Growth Hormone (HGH) - The levels of growth hormone skyrocket, increasing as much as 5-fold. This has benefits for fat loss and muscle gain, to name a few.

Gene expression - There are changes in the function of genes related to longevity and protection against disease.

These changes in hormone levels, cell function, and gene expression are responsible for the health benefits of intermittent fasting.

Is Intermittent Fasting Catabolic? (Muscle Wasting)

Stages of digesting energy:

  • After your body has used up the carbohydrates from a meal or snack, your cells begin to break down glucose stored in your muscles and liver known as glycogen. Glycogen stores vary in each person but are typically depleted within 24 hours, meaning your body has to begin breaking down other compounds for energy.
  • When glucose and glycogen are not available, your body preferentially breaks down fatty compounds known as triacylglycerol’s, which are present in adipose or fat tissue. Because fat is a high-energy source with nine calories per gram, fat provides an efficient fuel source. Additionally, your body metabolically prefers to preserve lean body mass and when possible, breaks down fat stores for fuel as much as possible. Only when your fat stores are extremely low or depleted does your body have to then break down protein.
  • When glucose and fat stores are depleted, your body will then turn to muscle to break down into individual amino acids for energy. Unlike carbohydrates and fat, your body does not store amino acids, which is why muscle breakdown is the only way to release amino acids for fuel.  

As we can see, there are many sources of fuel your body will use prior to having to break down muscle to amino acids for energy. After the exhaustion of the glycogen reserve, and for the next 2–3 days, fatty acids are the principal metabolic fuel. At first, the brain continues to use glucose, because, if a non-brain tissue is using fatty acids as its metabolic fuel, the use of glucose in the same tissue is switched off. Thus, when fatty acids are being broken down for energy, all of the remaining glucose is made available for use by the brain.

Now, this information is based on people who live a non-active lifestyle. As an athlete, you can deplete Glycogen and Fat stores much quicker than someone who is just starving nutrition. That being said it is almost impossible to be catabolic in a 24-hour window. The exception to this rule may apply to Elite Triathlon athletes who are doing a grueling 6-8 hour event pushing their body’s to the limit. 

What can you ingest while in a fasted state:

-Herbal Teas

-Black Coffee

-Zevia Sweetener

-Apple Cider Vinegar


-L-Carnitine Tartrate

-Diet Soda (stevia Sweetened)

-H20 (water)

-Carbonated Water


-Beta Alanine


-Sucralose (Small amounts) 

What you can’t ingest while in a fasted state:

-Bulletproof Coffee (butter)

-Coffee Creamer




-Bone Broth

-Erythritol (sugar alcohols)





-Nothing that has calories (to be fasted you cannot have any insulin spike)

The best way to start intermitting fasting is to be prepared ahead of time. You also have the option of transitioning into it with a slow approach; for example, start doing the 16:8 protocol a few times a week. This will help you get accustomed to not eating breakfast. You can also take the route of fasting for 12 hours when you initially start and then adding 1 hour a day longer until you reach 16 hours fasted.



We hope this short and brief blog has answered some of your questions on Intermittent Fasting.

For more information about Intermitting fasting, nutrition, training, and supplementation visit us in-store or contact us via Facebook, Instagram or give us a call! 

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