
Intermittent fasting (IF) is an eating pattern where you cycle between periods of eating and fasting.
Also known as intermediate fasting, it is not a diet but rather a style of eating.
You already fast every day while you sleep. Intermittent fasting simply extends that fast a little bit longer.
For example, if you eat your last meal at 8 pm, skip breakfast and then ate your first meal at noon, you fasted for 16 hours and restricted eating to an 8-hour eating window. The 16/8 method is the most popular form of intermittent fasting.
Intermittent fasting is very easy to do and most people actually report feeling better and having more energy during the fast.
Hunger is usually not an issue, although it can be a problem in the beginning while your body is getting used to not eating for extended periods of time.
The main benefit to intermediate fasting is lowered insulin levels. This allows for optimal fat loss and detoxification.
Related: 3 Things You Can Learn From Intermittent Fasting
Now don’t make the mistake of thinking that insulin is all bad. Insulin is an essential hormone that is needed by the body to absorb and utilize the food you eat. The tricky thing about insulin is that insulin is a storage hormone. Fat loss and detoxification are opposite bodily processes. Your body cannot burn fat and detoxify itself optimally when insulin is present.
The benefits of intermittent fasting go far beyond weight loss. Intermediate fasting has also been shown to improve heart health, reduce cancer risk, prevent type 2 diabetes, reduce inflammation and improve metabolic features important for brain health.

No food is allowed during the fasting period, but you can drink water, coffee, tea and non-caloric beverages.
Most forms of intermittent fasting allow small amounts of low-calorie foods such as greens powders and amino acid supplements during the fasting period. Although they contain calories, the calorie content is so small that it won’t break you out of the fast.
Similarly, taking supplements is generally allowed while fasting as long as they are non-caloric.
Hunger and irritability are the main side effects people experience while intermittent fasting. These side effects are usually only temporary as it takes time for your body to adapt to the new meal schedule.
Related: 5 Things "Diet Gurus" Don’t Want You to Know
If you have a medical condition, you should consult with your doctor before trying intermittent fasting. This is particularly important if you:
All that being said, intermittent fasting has an outstanding safety profile. There is nothing dangerous about fasting if you’re healthy and overall well-nourished.

1. Can I Drink Liquids During the Fast?
Yes. Water, coffee, tea and other non-caloric beverages are fine. However, do not add sugar.
2. Isn't It Unhealthy to Skip Breakfast?
No. Most stereotypical breakfast skippers have unhealthy lifestyles. Skipping breakfast in itself is not unhealthy.
3. Can I Take Supplements While Fasting?
Yes. However, some supplements like fat-soluble vitamins may work better when taken with meals.
4. Can I Work out While Fasted?
Yes. However, it is recommended to consume essential amino acids (EAAs) during a workout while fasting to prevent muscle loss.
5. Will Fasting Cause Muscle Loss?
All weight loss methods can cause muscle loss which is why it’s important to lift weights and keep dietary protein intake high. Generally speaking, muscle loss during fasting isn’t a concern unless you are fasting for periods greater than 24 hours.
6. Will Fasting Slow Down My Metabolism?
No. Studies show that short-term fasts actually boost metabolism. However, long duration fasts of 3 or more days can suppress metabolism.
7. Should Kids Fast?
Intermediate fasting is generally not recommended to anyone younger than 18 years of age.