How to Do the 20:4 Intermittent Fast

What is the 20:4 Intermittent Fast?

The 20:4 Intermittent Fast is a type of intermittent fasting where you fast for 20 hours and have a 4-hour eating window. During the fasting period, you can only consume water, black coffee, or tea without any additives. This type of fasting is believed to have various health benefits, including weight loss, improved insulin sensitivity, and reduced inflammation.

Benefits of a 20:4 Intermittent Fast

Insulin Sensitivity

Insulin sensitivity is improved when our bodies don’t need to be pumping out so much insulin constantly. Remember, when our blood sugars are high (consistently) then we need to produce insulin in order to lower it. When our bodies are constantly needing to produce insulin, overtime we become insulin resistant. Insulin sensitivity is the opposite of the insulin resistance phenomenon. When we fast, specifically during a 20:4 fast, our blood sugars are low and we stop having to push out insulin. When we eat again, our metabolic mechanism to lower blood sugar is more efficient and our insulin sensitivity is improved.

Inflammation

Chronically high levels of blood sugar in the body is essentially a toxin and creates inflammation. Studies have shown that eating less sugar in general can reduce inflammation. Insulin resistance also contribute to inflammation. When we improve insulin sensitivity, we also improve inflammation.

Body Composition

Fasting allows the body to burn more fat. Key word, FAT! If we burn more fat and maintain more muscle, then our body composition will improve. More lean muscle and less fat.

BDNF Production

BDNF stands for brain-derived neurotrophic factor. Studies have shown that BDNF is up-regulated by fasting. BDNF is linked to improved neuroplasticity, learning, and memory. Our mental performance and health can be improved with intermittent fasting.

HGH Production

Similarly to BDNF production, IGF-1 is stimulated by fasting. IGF-1 (Insulin Growth Factor 1) is the hormone responsible for increasing HGH (Human Growth Hormone) production. A study showed that an enhanced HGH rate was accounted for by 2 fold increases per 24hr. HGH production may increase muscle mass and reduce recovery time from physical activity.

Cellular Autophagy

Cellular autophagy is shown to begin around the 20-24 hour mark during a fast. Cellular autophagy is the break down and destruction of cellular waste in order to heal, repair, and recycle. Achieving neuronal autophagy is a key homeostatic process and one way to induce it is by food restriction (fasting).

20:4 Intermittent Fast and your Daily Routine

Stop Eating at a Reasonable Time the Night Before

In order to make your 20 hour fast more manageable, it is important to start your fast at a reasonable time the night before. This will only help you the next day to get to 20 hours “sooner”. Don’t be tempted by the late night munchies with the idea of “oh, well I’m fasting tomorrow so…” Stop eating immediately after your healthy on-time dinner.

Get a Good Nights Sleep

Get to sleep early, if possible. A good night of sleep will help you time wise, but also mentally and physically. When we are tired, we typically crave more. Make time to get to sleep and aim for 8-9 solid hours.

Drink Plenty of Water (Or Other Non-Calorie Drinks)

Hydration will be your best friend during a fast. When we are hydrated, our bodies typically calm down those hunger hormones. Keep a bottle of water close to you at all times and take some sips even when you are not thirsty. Oh, and take a big sip if you start to get a little hungry. Check out more in depth about what you can drink during an intermittent fast.

Stay Busy

Staying busy and distracted will help the hours fly by. If you know you have a busy day at work, maybe plan your 20 hour fast day to take place.

Know your Time Frames

Know exactly when your fast will end. If you start at 7PM the night before, your 20:4 fast will end at 3PM the following day. The worst thing would be to think your fast has ended and then you go ahead and count back to realize you still had some time left!

Here is a sample schedule…

Sample 20:4 Intermittent Fast Schedule:

Tuesday Evening

6PM: Make dinner

7PM: Finish dinner (Last meal)

10PM: Bedtime

Wednesday

630-7AM: Wake up

7AM: Drink a tall glass of water and have a cup of black coffee

11AM: Crack open a flavored seltzer water

1PM: Don’t forget to drink more water!

3PM: That’s it! Your 20 hours is up. 

3PM-Have a healthy snack (yogurt, fruit, nuts, etc.)

5PM- Eat dinner

6PM- Have another healthy snack if you’re still hungry…

Can 20:4 intermittent fasting help me lose weight?

Yes! Increased fat mass is a problem of too much blood sugar longterm. Intermittent fasting can be a great tool to burn fat and keep it off. It is important to note that we cannot store food “energy” and burn it at the same time. We are either in one state or the other in terms of metabolic function. During a prolonged fast (longer than a typical overnight fast) our body breaks down fat and glycogen. 

A 20:4 intermittent fast pushes your body to burn more fat compared to a 16:8 intermittent fast? Why? Because your body simply has more time to continue burning fat stores while your blood sugar is down.

it’s important to note that this type of fasting may not be suitable for everyone and it’s always best to consult with a healthcare professional before starting any new diet or exercise regimen.

20:4 Intermittent Fast: Conclusion

The 20:4 Intermittent Fast involves eating all of your daily calories within a 4-hour window and then fasting for the remaining 20 hours of the day. While your blood sugar is consistently low for hours on hours in a fasted state, your body can begin to burn fat and glycogen. Your body also benefits from improved insulin sensitivity, decreased inflammation, leaner muscle mass body composition, BDNF HGH production, and possibly even cellular autophagy. The longer the fast, the further this scenario continues…however, there are other metabolic processes that become affected such as potential protein depletion and muscle loss. More to come on that for another time!

Please consult your physician before starting a new eating regimen.

Find a intermittent fasting routine that suits you and stay consistent!