What is intermittent fasting?
Intermittent fasting also is known as IF, is a way of cycling between periods of fasting and eating. It’s not so much of a diet as it is a method of eating. Most commonly it takes the form of a 16hrs on eating and 8 hours off (also known as lean gains method), or 5 days eating with a two day fast/reduced food consumption or periods of 24-hour fasts once to twice a week.
Much of the popularity of the method comes from its simplicity; it’s a way which is easy to implement and provides ongoing results. Take the 16/8 method; one can adjust their eating pattern to fasting from 8 p.m. to 12 pm the next day. This works well with a lot of busy schedules and still leaves one with enough energy to perform at the gym. The 5 2 method could look like; weekdays as normal and weekends only consuming around 500 calories a day.
How does it work?
IF operates in a few ways to help you reduce body fat and increase lean muscle mass. Firstly, by waiting 12+ hours between first and last meals your body can enter a fat burning stage. Secondly, it increases levels of the fat burning hormones such as; norepinephrine (noradrenaline) and human growth hormone (the levels can skyrocket, increasing as much as 5-fold), Insulin sensitivity improves and levels of insulin drop dramatically. Lower insulin levels make stored body fat more accessible. Thirdly, limiting the hours you’re able to eat can have a calorie deficit effect. Eating your usual amount of calories in just an 8-hour timeframe or eating seven days of calories in 5 days can be harder than it sounds.
• Weight Loss: As mentioned above, intermittent fasting can help you drop weight and body fat, without having to restrict calories consciously.
• Insulin resistance: Intermittent fasting can reduce insulin resistance, depressing blood sugar by 3-6% and fasting insulin levels by 20-31%. This can also help protect against type 2 diabetes.
• Inflammation: Some studies show decreases in markers of inflammation, a key driver of numerous 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 have suggested that intermittent fasting may help prevent cancer. However much more research in this area needs to be done.
• Brain Health: Intermittent fasting increases a brain hormone Brain-derived neurotrophic factor, also known as 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.
Different types of IF
Lean Gains: Created by Martin Berkhan, the central ideas behind the Lean Gains dieting program involve limiting calorie consumption for 16 hours, followed by 8 hours of eating. Berkhan proposes aiming for a higher protein intake on workout days and ranking carbohydrates over fat. Rest days should have lower calories compared to training days, continuing the high protein intake but flipping fat and carbohydrate intake.
The Alternate-Day Diet: Created by James Johnson, M.D., the Alternate-Day Diet, also known as the UpDayDownDay Diet®, follows a 24-hour rotation of low-calorie intake and average calorie intake. It's believed that the alternating days of caloric intake help to activate the SIRT1 gene, which supports weight loss by inhibiting fat storage and driving increased fat metabolism (in mice, anyway).
The Warrior Diet: Written by Ori Hofmekler, is another intermittent fasting protocol. Described by the author, the diet pairs a 20-hour fast with a 4-hour feeding window. The goal of this is to increase the actions of the Sympathetic Nervous System which may help to stimulate lipolysis and increase metabolic rate.
Eat-Stop-Eat: This involves fasting for 24 hours, once or twice a week, for example by not eating 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 five days.
My recommendation is to cycle between 2 of these over a 4-6 week period. This keeps the body guessing and constantly trying to adapt, which will mean the pounds will keep coming off at a steady pace.
If you have a medical condition, then you should always consult with a doctor before trying intermittent fasting, or any new eating schedule. However, this is of particular importance if you:
• Have diabetes.
• Have problems with blood sugar regulation.
• Have low blood pressure.
• Take prescribed medications.
• Are underweight.
• Have a history of eating disorders.
• Are a woman who is attempting to conceive.
• Are pregnant or breastfeeding.
Some supplements that may be beneficial while partaking in an IF protocol are;
• BCAA – sipping on these during the day may help to reduce catabolism and increase protein synthesis
• Creatine – again this can reduce catabolism and can support better workouts
• Beta-alanine - has been shown to support greater work capacity
• Whey protein – whey protein can be useful to breakfast as the body easily and quickly absorbs it
To conclude intermittent fasting is a useful way to decrease your waistline while still gaining muscle. It's become popularised of late, and for a good reason, it's easy to do has real science behind it along with a vast and ever growing amount of anecdotal evidence. Our suggestion is to give it a try for 4 – 6 weeks and see if its right for you.