Intermittent fasting has over the last ten years gained popularity as a means of controlling eating patterns; weight loss and allowing the body to regulate itself. It involves fasting over a period of time throughout the day. This can be anywhere from 12-20hrs or alternatively, for a 24hr period a couple of days a week. It is not a diet as such, but more an eating plan restricting food consumption during specified periods of time.
The central themes around intermittent fasting are that it is a more natural way to eat. It is based on how our hunter-gatherer ancestors would only have had limited access to food. Much of this would have been dependent on what they could catch. As such our bodies evolved into being able to go without food for long periods of time and using stored fat as fuel.
With many contemporary western diets, our eating habits are irregular, partly due to lifestyle and work pressures. The traditional sit down for breakfast, lunch and dinner model is seemingly broke. This is since many of us are not at home when we would like to be. We eat at sporadic hours, whenever we can. Many of us skip breakfasts, cram food in during the day, overeat and it is common for many to eat before bedtime.
These poor eating times arguably don’t allow the body time to process food effectively. Our bodies are in a constant cycle of having to deal with bulks of food and the resultant blood sugar spikes. As such, there is always an overabundance of glucose in the blood. By being in a continuous ‘fed’ state, the energy we consume is utilised inefficiently and much of this is stored as fat (weight gain).
Reported Health Benefits
Staged eating times via intermittent fasting has reportedly demonstrated many benefits with its participants, including:
- Weight loss and belly fat loss.
- Insulin resistance/lowering of blood sugar (reduces the chances of diabetes and makes stored body fat more accessible for use as fuel).
- Reduced inflammation (reduced likelihood of chronic diseases).
- Improved heart health.
- Cancer prevention.
- Improving cerebral nerve cell growth (brain power).
- Protection from conditions such as Alzheimer’s disease.
- Anti-aging qualities.
- Increased HGH (Human Growth Hormone) production (important in muscle gain and fat loss).
- Cell repair by a process known as Autophagy (removes old dead or poorly functioning cells and produces new ones).
How Intermittent Fasting Works
- Food that we consume is broken down into Glycogen, then glucose molecules to provide energy for the cells of our bodies. There is usually an abundance of Glycogen in the blood to get the body through a 24hr period.
- When there is a surplus of food energy ingested than can immediately be used, some of this energy is stored away for later use.
- Insulin is the hormone involved in this storing process. It packages excess energy from food into fat stores for later use. So put very simply, body fat is food energy that has been stored away for later use.
- When we stop eating for long periods (as with intermittent fasting), blood glucose and insulin levels fall. This signals the body to start using stored energy from fat sources since there is no more is coming through food.
- The body, therefore, goes through two states, ‘fed’ when insulin levels are high and ‘fasted’ when insulin levels are low. So we are either storing food energy as fat, or our bodies are making a fat withdrawal and using it for fuel.
- When our eating and fasting habits are balanced, there should be no weight gain, but problems occur when we overeat. If we are eating continually throughout the day (6 times a day eating plans), then our bodies spend the majority of the day in a ‘fed’ state. Our bodies will simply use the incoming food for energy and never actually utilize fat stores for fuel. The body will simply continue to store the fat, which will mean further weight gain.
- To create a or drop weight, we simply need to increase the amount of time we spend in the ‘fasted’ state. That essentially is intermittent fasting, the fasting allows the body to utilize its stored energy. By not eating for long periods, your body will simply break down its own fat for energy.
Popular Intermittent Fasting Methods
- The 16/8 Method: Also known as the Leangains protocol (Developed by Martin Berkhan). This method involves limiting your daily eating period to eight hours, for example from 8 am to 4 pm. The fasting portion is the remaining sixteen hours of the day. Participants are encouraged not to eat as soon as they awake for four hours and keep the body in its fasted state until that period is over. https://leangains.com/the-leangains-guide/
- Eat-Stop-Eat: Eat Stop Eat (Developed by Brad Pilon) involves a 24-hour fast, once or twice a week. For example, eating Sunday, Monday, Tuesday normally. Full 24hrs fast on Wednesday. Normal eating Thursday and Friday. Another Fast on Saturday. https://www.eatstopeat.com/
- The 5:2 Diet: (Developed by Ori Hofmekler) involves consuming only 500-600 calories on two non-consecutive days of the week. On the other five days, normal eating patterns are followed. http://www.orihofmekler.com/
General Eating and Fasting Rules across the Various Plans
- Zero calories: to be ingested during the fasted phase.
- Meal frequency: during the feeding phase is irrelevant. Spread the feeding out over your eating times as you see fit.
- Aqua Vitae: Drink lots of water. Stay well hydrated.
- What to drink during the fast: The jury is out on what can actually be consumed during the fasting periods. Some argue only non-calorific liquids water or tea and coffee (without milk or sugar). Or zero-calories drinks with artificial sweeteners (no sugars!!). Others are more lenient and say a splash of milk in hot beverages will do no harm. Coffee can be particularly beneficial during a fast because it can blunt hunger.
- Fasted workouts: Fasted workouts are fine. Some people recommend taking branched-chain amino acids (BCAAs) before a fasted workout.
- Fasting and Muscle Loss: All weight loss methods can cause muscle loss. When undertaking weights, keep protein intake higher to keep lean muscles mass and encourage fat loss. The BCAA’s should again be of assistance here.
- Use Low-intensity cardio only if fasting: Know thy limitations, and stop exercising, if you feel light-headed or dizzy. Use BCAA’s for pre and post-fuel.
- High-intensity only after you’ve eaten: Try to schedule higher intensity workouts closer to your last meal, so you have some glycogen to fuel your workout.
- High-protein meals: Eat before and after lifting. Protein consumption is necessary asap after your strength workout when your muscles are craving amino acids to repair and grow. Take roughly 20 to 30 grams of high-quality protein every four hours during waking hours, including after training. Also, try to time strength training workouts so that they are between two meals.
- Overnight fasting: Make it easy on yourself!! Fast whilst sleeping!!
- Keep busy: If you are finding it a struggle, keep busy to help take your mind off of things.
- Rest days: First meal should ideally be the largest meal. As opposed to training days where the post-workout meal is the largest meal.
Some intermittent fasting diets recommend that you do some sort of fasted exercise. That is, exercise when insulin levels are low and body fat is the primary source of energy. The theory is that it increases lipolysis and fat oxidation rates. This enables the body to burn more fat than normal in its fasted state. The blood supply to the abdominal region is also apparently increased whilst the body is in a fasted state. This is because fasted training assists with impaired blood flow which usually limits fat burning in this region.
A downside to fasted exercise to be aware of is that it can increase muscle breakdown rates. This could potentially mean lean muscles mass loss and some experience people mental/physical fatigue from having less energy. I have found using BCAA (Branch Chain Amino Acids) prior and after training a good workaround for this. Although I do personally seem to have more energy in a fasted state than if I had eaten earlier.
Critique of intermittent fasting
Although intermittent fasting has been shown to have benefits, it certainly isn’t for everyone, it is not recommended for pregnant women; people with diabetes or other similar eating disorders; individuals who suffer from stress or sleeping disorders and those who are new to dieting.
Some people struggle with intermittent fasting earlier on, with hunger, weakness, and lethargy being the main side effects after beginning the plan. Like adapting to anything, be it exercise or any kind of diet, the body needs time to adapt to the changes. I did develop crazy hunger pangs myself initially, thankfully it proved only temporary, as my body adapted to the new meal schedule. Since starting I have experienced a few difficulties and actually feel better overall.
One counter-argument for intermittent fasting weight loss is that the limited eating times simply put participants into calorific deficit. Naturally, it would do this if calorie consumption was actually reduced. However, since intermittent fasting does not actually require calorie reduction but limiting daily eating times, it renders that argument invalid.
An average day on the Leangains protocol
For me personally, I had read a lot on the major IF diets and opted for the Leangains Protocol. I based the decision on my work pattern, training and other commitments throughout my working week. This was the one that I believed I could utilise most effectively for my fat loss requirements.
The Leangains Protocol involves 16 hours of fasting, followed by 8 hours of feeding. During this period, three meals are usually eaten. Depending on the day, the composition of those meals varies; on workout days, Carbohydrates are prioritised before Fat, while on rest days Fat intake is higher. Protein remains fairly high on all days. That’s a very basic and general description of the protocol I employ. Of course, variables change depending on goals, gender, age, body fat and activity levels, but it would be hard to describe it in greater detail without drifting off too far.
On workout days, vegetables and fruit for breakfast. With some starchy carbohydrates added prior to any training. With regards to portion sizes, medium-sized portions are encouraged. Training within 3 hours of having eaten this meal is recommended with a much larger meal after the workout; which should consist of more complex carbs.
For rest days, eating fewer calories (compared to workout days); cutting down on Carbohydrate intake; meat; fibrous vegetables, and fruit should be the foundation of your diet on this day. The first meal of the day should be the largest, compared to workout days where the post-workout meal is the largest. The dominant macronutrient should be protein, so fattier meat and fish (beef and salmon for example).
For the last meal of the day, try a slow-digesting protein source; preferably egg protein, cottage cheese (or any other source of casein-based protein). Meat or fish is also ok if you add vegetables or a supplement with fiber.
Whole and unprocessed foods are recommended before processed or liquid foods unless circumstance demands a compromise. For example, you might find yourself in situations when there is little time to eat or prepare food.
Intermittent fasting is simply an eating plan that may/may not work for you. The arguments ‘for’ suggest that it does improve your health overall. That said, the long periods of fasting may be too much for those used to more regular eating periods. Granted, the eating plan is not for everybody, and this is fine. If it doesn’t work for you find something that does. There is only one correct diet at the end of the day and that is the one that works for you specifically.
In its defense, I have found intermittent fasting to be a valuable tool in helping me drop weight quickly and effectively (post-holidays!). It helps me balance out my eating habits, is easy for weekly planning, and is less stressful (no rushing around for food in the evenings). Overall, I feel my health is a lot better, with training and adequate nutrition I manage to drop weight and keep lean muscle very effectively.
Ok, so it has worked for me the only way you will know if it is for you is if you give it a try! Happy fasting!