Intermittent Fasting is one of the buzzwords in the health and fitness circles, and looks like it is here to stay, with its benefits and results being endorsed by many health gurus, nutritionists and celebrities. Let’s take a look at what you need to know.

What Is Intermittent Fasting (IF)

Intermittent fasting (IF) basically refers to an eating pattern that cycles between periods of fasting and feasting (eating). It focuses simply on when you eat, and not what you eat.

Fasting is not new to humanity. It has been a part of life for our hunter-gatherer ancestors who didn’t have easy access to food like we do today. Our bodies evolved to be able to function without food for extended periods of time.

Also, fasting has also been a part of major religions, including Hinduism, Islam, Christianity and Buddhism. Humans and other animals also often instinctively fast when sick.

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

Why do Intermittent Fasting

Here are some evidence-based health benefits of IF. You can find the details here.

1. Weight Loss: IF helps you eat fewer calories, while boosting metabolism slightly and assisting in weight loss.

2. Insulin resistance: IF can reduce insulin resistance, lowering blood sugar by 3-6% and fasting insulin levels by 20-31%. This should protect against type 2 diabetes.

3. Inflammation: Studies have shown reductions in markers of inflammation, a key driver of many chronic diseases.

4. Heart Health: IF may reduce LDL cholesterol, blood triglycerides, inflammatory markers, blood sugar and insulin resistance. These are all risk factors for heart disease.

5. Brain Health, Anti-aging: IF increases a brain hormone called BDNF, and may aid the growth of new nerve cells. It may also protect against Alzheimer’s disease.

Additionally, IF makes healthy eating simpler. There are fewer meals that you need to prepare, cook and clean up after.

How to do Intermittent Fasting

There are several different ways to do intermittent fasting. All of them split the day or week into “eating periods” and “fasting periods.” During the fasting periods, you eat either very little (less than 50 claories) or nothing at all.

These are the most popular methods:

1. The 16/8 (or Leangains) Protocol: Popularized by Martin Berkhan, a fitness expert. This involves fasting for 14-16 hours and restricting your daily eating period to 8 hours. An example is to finish dinner by 8 pm and fast until lunch 12 pm the next day. It is generally recommended that women only fast 14-15 hours, because they seem to do better with slightly shorter fasts.

2. Eat-Stop-Eat: Popularized by Brad Pilon, an expert on IF.This involves fasting for 24 hours, once or twice a week. An example is to finish dinner at 8 pm and not eating until 8 pm the next day.

3. The 5:2 Fast Diet: Popularized by British doctor and journalist Michael Mosley. On two non-consecutive days of the week, only eat 500-600 calories. Eat normally the other 5 days. 

4. Alternate Day Fasting: This involves fasting for 24 hours every other day; either by not eating anything or only eating a few hundred calories.

5. Spontaneous Meal Skipping: This is pretty straight forward – skipping 1 or 2 meals when you don’t feel hungry or are too busy to cook and/or eat.

By making you eat fewer calories, all of these methods should help you lose weight as long as you don’t compensate by eating junk food or excessive calories during the eating window. It is very important to eat mostly healthy foods during your eating window. IF is not an excuse to eat junk or overeat. 

Conceptually, glucose is available in the blood and glycogen stores are filled in the muscles and liver in a traditional weight loss plan, thus the body relies less on stored fat.  However, on fasting days when glucose is not as readily available, the body turns more quickly to fat as a fuel source.

Personally I find the 16/8 method to be the simplest, most sustainable and easiest to stick to. It is also the most popular.

Is Intermittent Fasting for You

Intermittent fasting is certainly not for everyone. First, establish if IF is not for you.

Medical conditions such as diabetes require a more equal distribution of food intake or use certain medications that require specific food intake patterns. Furthermore, if you are underweight, involved in an intense athletic training program or you have a history of eating disorders, IF may be downright harmful.

Women should should definitely be careful with intermittent fasting. IF is probably a bad idea when breastfeeding, pregnant, trying to conceive or having problems with fertility. Also, there have been reports from women who became amenorrheic (their menstrual period stopped) when they started doing IF, then went back to normal when they stopped doing it. Ease into it, and if you have any problems like amenorrhea then stop doing it immediately. 

Consider consulting with a health professional first to get the green light before starting an eating program like IF.

Intermittent Fasting, the Smart Way

If you want to get started with an IF program, be wise and do a trial for two to three weeks. Monitor how you feel and record your weekly weight loss.  Tweak your program along the way so that you continue without feeling dizzy, light-headed or fatigued. If you continue to struggle with such symptoms, face the fact that IF is not for everyone.

IF is not something that anyone needs to do. It is just one of many lifestyle strategies that can improve your health. Eating real food, exercising and taking care of your sleep are still the most important factors to focus on.

If you don’t like the idea of fasting, then you can safely ignore all of this. Just continue to do what works for you. You know your body best, so follow your gut.

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.

At the end of the day, there is no one-size-fits-all solution in nutrition. The best eating pattern for you is the one you can stick to in the long run.

For more details on Intermittent Fasting, visit Authority Nutrition and Spark People.