Intermittent fasting (IF) is currently one of the world’s most popular health and fitness trends. People are using it to lose weight, improve health and simplify their healthy lifestyle.

Intermittent fasting (IF) is a term for an eating pattern that cycles between periods of fasting and eating.

It does not say anything about which foods you should eat, but rather when you should eat them. In this respect, it is not a “diet” in the conventional sense. It is more accurately described as an “eating pattern.”

Common IF methods involve daily 16 hour fasts, or fasting for 24 hours, twice per week.

Humans have actually been fasting throughout evolution. Sometimes it was done because food was not available, and it has also been a part of major religions, including Islam, Christianity and Buddhism. When you think about it, our hunter-gatherer ancestors didn’t have supermarkets, refrigerators or food available year-round. Sometimes we couldn’t find anything to eat, and our bodies evolved to be able to function without food for extended periods of time.

If anything, fasting from time to time is more “natural” than constantly eating 3-4 (or more) meals per day.

These are the most popular methods:

• The 16/8 Method: Also called the Leangains protocol, it involves skipping breakfast and restricting your daily eating period to 8 hours, for example from 1 pm to 9 pm. Then you “fast” for 16 hours in between.
• Eat-Stop-Eat: This involves fasting for 24 hours, once or twice a week, for example by not eating from dinner one day until dinner the next day.
• The 5:2 Diet: On two non-consecutive days of the week, only eat 500-600 calories. Eat normally the other 5 days.

By making you eat fewer calories, all of these methods should make you lose weight as long as you don’t compensate by eating much more during the eating periods.

I’ve personally found the 16/8 method to be the simplest, most sustainable and easiest to stick to. It is also the most popular.

How Intermittent Fasting Affects Your Cells and Hormones

When you fast, your body changes hormone levels to make stored body fat more accessible. Your cells also initiate important repair processes, and change the expression of genes.

Here are some changes that occur in your body when you fast:

• 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 .
• Insulin: Insulin sensitivity improves and levels of insulin drop dramatically. Lower insulin levels make stored body fat more accessible.
• Cellular repair: When fasted, your cells initiate cellular repair processes. This includes autophagy, where cells digest and remove old and dysfunctional proteins that build up inside cells.
• Gene expression: There are changes in the function of genes related to longevity and protection against disease.
• By making you eat fewer meals, intermittent fasting can lead to an automatic reduction in calorie intake. In addition to lower insulin and increased growth hormone levels, it increases release of the fat burning hormone norepinephrine (noradrenaline). Because of these changes in hormones, short-term fasting may  increase your metabolic rate. By helping you eat less (fewer calories in) and helping you burn more (more calories out), intermittent fasting causes weight loss by changing both sides of the calorie equation.

Studies show that intermittent fasting can be a very powerful weight loss tool. In a review study from 2014, it was shown to cause weight loss of 3-8% over periods of 3-24 weeks.

That is actually a very large amount compared to most weight loss studies.

According to this study, people also lost 4-7% of their waist circumference. This indicates that they lost significant amounts of the harmful belly fat that builds up around the organs and causes disease. This is an extremely important reason to adopt this practice.

There is also one study showing that intermittent fasting causes less muscle loss than the more standard method of continuous calorie restriction.

Health Benefits of Intermittent Fasting

• Weight Loss: As mentioned above, intermittent fasting can help you lose weight and belly fat, without having to consciously restrict calories.
• Insulin resistance: Intermittent fasting can reduce insulin resistance, lowering blood sugar by 3-6% and fasting insulin levels by 20-31%. This should protect against type 2 diabetes.
• Inflammation: Some studies show reductions in markers of inflammation, a key driver of many chronic diseases.
• Heart Health: Intermittent fasting may reduce LDL cholesterol, blood triglycerides, inflammatory markers, blood sugar and insulin resistance. These are all risk factors for heart disease.
• Cancer: Animal studies suggest that intermittent fasting may help prevent cancer.
• Brain Health: Intermittent fasting increases a brain hormone called BDNF, and may aid the growth of new nerve cells. It may also protect against Alzheimer’s disease.
• Anti-aging: Intermittent fasting can extend lifespan in rats. Studies showed that fasted rats live as much as 36-83% longer.

Intermittent Fasting Makes Your Healthy Lifestyle Simpler

Eating healthy is simple, but it can be incredibly hard to stick to. One of the main obstacles is all the work required to plan for and cook healthy meals.

If you do intermittent fasting, this gets easier because you don’t need to plan, cook or clean up after as many meals as before.

Now, when I am out and don’t want to eat an unhealthy meal, I simply skip it and wait to reach home.

Intermittent fasting is actually very popular among the “life hacking” crowd because it improves your health while simplifying your life at the same time!

Safety and Side Effects

Hunger is the main side effect of intermittent fasting. You may also feel week and that your brain isn’t performing as well as you’re used to. This may only be temporary, as it can take some time for your body to adapt to the new meal schedule. Also we are used to eating frequently and weakness may be a psychological effect. It certainly was for me. I felt I couldn’t go a few hours without eating, I would develop hypoglycemic headaches. But now that I understand how IF works, I am able to go 24 hours without eating, without any side effects!

If you have a medical condition, then you should consult with your (Integrative Medicine) doctor before trying intermittent fasting.

This is particularly important if you:

• Have diabetes.
• Have problems with blood sugar regulation.
• Have low blood pressure.
• Take medications.
• Are underweight.
• Have a history of eating disorders.
• Are a female who is trying to conceive.
• Are a female with a history of amenorrhea.
• Are pregnant or breastfeeding.

All that being said, intermittent fasting does have an outstanding safety profile. There is nothing “dangerous” about not eating for a while if you are healthy and well nourished overall.

Frequently Asked Questions About Intermittent Fasting

Here are answers to the most common questions about intermittent fasting.

1. Can I drink liquids during the fast?

Yes. Water, coffee, tea and other non-caloric beverages are fine and can be particularly beneficial during a fast, because they can blunt hunger. Do not add sugar, though.

2. Isn’t it unhealthy to skip breakfast?

No. It is a myth that we can’t do without breakfast.

3. Can I take supplements while fasting?

Yes. However, keep in mind that some supplements (like fat-soluble vitamins) may work better when taken with meals.

4. Can I work out while fasting?

Yes, fasted workouts are fine.

5. Will fasting cause muscle loss?

All weight loss methods can cause muscle loss, that is why it is important to lift weights and keep protein intake high. One study shows that intermittent fasting causes less muscle loss than regular calorie restriction.

6. Will fasting slow down my metabolism?

No. Studies show that short-term fasts actually boost metabolism.

7. Should kids fast?

Sure they can, for short periods.

How to Start

Chances are that you’ve already done many “intermittent fasts” in your life.

If you’ve ever eaten dinner, then slept late and not eaten until lunch the next day, then you’ve probably already done a 16+ hour fast. Many people actually instinctively eat this way. They simply don’t feel hungry in the morning.

I personally find that the 16/8 method is the simplest and most sustainable way to do intermittent fasting. Another approach is to simply fast whenever it is convenient. As in, skip meals from time to time when you’re not hungry or don’t have time to cook.

Type 2 diabetes has become an absolute epidemic in all age groups. It seems pretty obvious that this is a balance problem. If you feast, you must fast. If you keep all the feasting and lose all the fasting, you get fat. That’s really not so hard to understand, is it?

But what happens when you lose all the feasting? Well, then life becomes a little less special. If you are the guy at the wedding who won’t drink, who won’t eat the cake, who won’t eat the full meal, who won’t eat the appetizers  – there’s a name for that – the party pooper.

Maybe you can keep it up for 6 months, or 12 months. But forever? Heck, not even the most extreme religions did that. That’s pretty hard to do. Life is full of ups and downs. Celebrate the ups because the downs are right around the corner. But you must balance the periods of eating a lot with periods of eating very little. It’s all a matter of balance.
If you feel good when fasting and find it to be a sustainable way of eating, then it can be a very powerful tool to lose weight and improve health.

Be Healthy.