*Edit Feb. 12 2015: I added a list of studies supporting the benefits of IF at the end of the article, be sure to read further for more information.
You can also find more links to the science behind fasting in the articles below we’ve written on the subject:
Intermittent fasting can provide many important health benefits, including improving your insulin/leptin sensitivity, helping your body more effectively burn fat for fuel, increasing mental clarity and overall energy levels, and more.
For years I agonized over finding the diet, eating schedule, and workout routine that best suited my goals and lifestyle. It took up a ton of mental energy and time. However, it didn’t matter what I tried or how enthusiastic I was about a new plan of attack for my diet and fitness, sooner or later I would fall off track for various reasons, with much disappointment.
I tried the ‘six small meals a day’ plan, I tried a 100% whole-food diet, I blended, I chopped. I tried numerous workout plans as well, but nothing seemed to be truly resonating with my body. I found myself lethargic most of the day, sick of always planning my meals, and frustrated that with how much effort I was putting into planning my diet and workouts, I still wasn’t seeing or feeling the results I had hoped for.
But this all changed when I discovered intermittent fasting (IF). I had heard a few things here and there, but I’d never fully entertained the topic.
After reading about the incredible health benefits of IF, something finally clicked within my brain. Call it my intuition or my ‘aha!’ moment, but something was telling me that this new approach to eating and fitness was the one I had been waiting for.
Why So Many Struggle With Their Weight
The reason so many struggle with their weight (aside from eating processed foods that have been grossly altered from their natural state) is because they’re in continuous feast mode and rarely ever go without a meal.
As a result, their bodies have adapted to burning sugar as its primary fuel, which down-regulates the enzymes that utilize and burn stored fat. Fasting is an excellent way to “reboot” your metabolism so your body can start burning fat as its primary fuel, which will help you shed your unwanted fat stores.
Once your insulin resistance improves and you are normal weight you can start eating more frequently, as by then you will have reestablished your body’s ability to burn fat for fuel—that’s the key to sustained weight management.
The amount of research around fasting and particularly intermittent fasting is growing exponentially. Let’s explore what the research is saying.
How & Why Intermittent Fasting Works
One 2013 review found a broad range of therapeutic potential in intermittent fasting, even when total calorie intake per day did not change, or was only slightly reduced. Studies included in the review produced evidence that intermittent fasting may:
- Limit inflammation
- Improve circulating glucose and lipid levels
- Reduce blood pressure
- Improve metabolic efficiency and body composition, including significant reductions in body weight in obese individuals
- Reduce LDL and total cholesterol levels
- Help prevent type 2 diabetes, as well as slow its progression
- Reverse type 2 diabetes
- Improve pancreatic function
- Improve insulin levels and insulin sensitivity
- Reproduce some of the cardiovascular benefits associated with physical exercise
- Protect against cardiovascular disease
- Modulate levels of dangerous visceral fat
The reasons for these health benefits relate to the fact that the human body appears to be designed to thrive in a cycle of “feast and famine.” By imitating the ancestral conditions of cyclical nourishment, your body enters into a state of optimal functioning. Three major mechanisms by which fasting benefits your health include:
- Increased insulin sensitivity and mitochondrial energy efficiency – Fasting increases insulin sensitivity along with mitochondrial energy efficiency, and thereby retards aging and disease, which are typically associated with loss of insulin sensitivity and declined mitochondrial energy.
- Reduced oxidative stress – Fasting decreases the accumulation of oxidative radicals in the cell, and thereby prevents oxidative damage to cellular proteins, lipids, and nucleic acids associated with aging and disease.
- Increased capacity to resist stress, disease and aging – Fasting induces a cellular stress response (similar to that induced by exercise) in which cells up-regulate the expression of genes that increase the capacity to cope with stress and resist disease and aging.
The Benefits Of Exercising In A Fasted State
We’ve often been told to make sure we are well fed before a workout, but this notion has been a hot topic of debate in recent years.
When we think about the cyclical eating patterns of our ancestors, we know that there were many cases in which they would perform rigorous physical activity on an empty stomach, such as during their hunt for food. Today, research confirms the biological benefits of this type of eating schedule.
John Rowley, Wellness Director for the International Sports Science Association (ISSA) elaborated on this concept to the Huffington Post:
Exercisers with weight loss goals might find an advantage in waking up and exercising first thing in the morning before eating breakfast or fasting for a few hours before a mid-day or evening workout. ‘The less glucose you have in your system the more fat you will burn,’ says Rowley. However, if your goals are performance related (e.g. to improve strength or speed), working out without fueling up probably isn’t your best bet because a lack of available energy might prevent you from putting forth your best effort.
What About Gaining Muscle While Intermittent Fasting?
For men or women who are looking to stay lean while gaining muscle mass, Martin Berkhan from Leangains.com has the optimal solution for this goal.
His methodological approach to intermittent fasting has helped so many achieve their fitness goals that he can easily be considered the expert in the realm of intermittent fasting and muscle gain.
Berkhan offers various types of fasting schedules so that people can choose which one works best with their lifestyle. Personally, I chose his recommended 12pm-8pm eating window followed by a 16-hour fasting period. So far I’ve found this schedule fantastic for a few reasons.
For one, I don’t have to worry about making breakfast as soon as I wake up which to me was becoming a hassle. This goes for late night eating, I know that my eating window stops after 8pm which is convenient in that I know exactly when to eat and when not to.
One important note that Berkhan stresses is that if you are going to be lifting heavy weights or training hard, make sure to ingest either a scoop of protein powder or a scoop of branched chain amino acids (BCAAs) 5-10 minutes before your workout. Doing this sidesteps the increased protein breakdown of fasted training while still reaping the benefits of the increased anabolic response as seen in this study.
Another important factor to remember is to make sure you are eating lots during your 8 hour eating window. Starving yourself combined with fasting while exercising regularly is sure fired way for exhaustion and nutrient depletion.
Here is how my schedule looks on a heavy workout day (taking into account my goal is to be building muscle):
7:30-8:00 am: Wake up and ingest 10 grams of BCAAs.
8:30 am: Workout.
10:00 am: Another scoop of BCAAs or protein powder. Cup of coffee and then work or errands before I break the fast.
12:00 pm: Post-workout meal/Fast-breaking meal. (Should be the biggest meal of the day. Keep protein and carbs high.)
3:00 pm: 2nd post-workout meal.
7:30 pm: 3rd meal of the day. Again, keeping protein and carbs high.
9:00 pm: Tea and water galore!
*Remember, you can create the type of fasting schedule you want based on your lifestyle. Some people fast for 14 hours, while others fast up to 24+ hours. That is why IF can work for anyone.
Is IF For You?
The results thus far have been very pleasing. I’m finally seeing my abs for the first time in years, I have overall increased muscle definition and composition, my energy levels are through the roof, and my hunger levels have subsided for the most part.
Tea, coffee, and water are allowed as much as you like during the fasting state so long as you don’t exceed 50 calories in sugar or milk.
There is so much more information available regarding intermittent fasting that it is difficult to explore within this single article, so stay tuned for more articles regarding IF in the very near future.
For now, I recommend reading more about the amazing benefits of IF to see if it is right for you.
More CE articles discussing IF:
http://www.ncbi.nlm.nih.gov/pubmed/22425331 (IF and lower cases of diabetes/heart disease)
http://www.ncbi.nlm.nih.gov/pubmed/18805103 (IF and reducing coronary heart disease, one of the biggest killers of our time)
http://www.ncbi.nlm.nih.gov/pubmed/21410865?dopt=Abstract (Why IF is the best for fat loss)
http://www.ncbi.nlm.nih.gov/pubmed/15699226 (Why skipping breakfast is good for your health)
Have you had any success with intermittent fasting? Share with us in the comment section below!