Intermittent fasting is a form of eating pattern that cycles time bound windows of eating and fasting. It is not a diet in the conventional term as there is no stipulation to which food or food sources are to be consumed, simply the schedule in which they are consumed.
For our ancestors, fasting was a normal way of life, eating only when food was available. While periods of fasting are often part of many religions including Islam, Christianity and Buddhism. There is an infinite amount of ways to do intermittent fasting, there are four common methods:
- The 16/8 method: This represents a 16 hour fasting period and an 8 hour eating period, each day.
- The 5:2 diet: This involves 5 days of normal eating and 2 non-consecutive days of heavily restricted -500 calories per day- eating or complete fasting.
- ‘Eat-stop-eat’: Often used as a weekly or monthly cleanse, this involves periodically fasting for 1-3 days.
- ‘The warrior diet’: One meal/short eating period per day.
Whilst the 16/8 method appears to be the most popular -also the method I personally follow-, all four boast many common and some unique benefits. Which method suits you better is entirely a personal choice, often made based upon lifestyle habits.
So, what are the benefits?
- Hormonal - Studies have shown Intermittent Fasting can increase HGH by up to 5 x, this reaps rewards in fat loss, muscle gain and longevity (1)
- Autophagy / cell repair - The relief from digestion allows the body to repair cells and remove old dysfunctional cells (2)
- Insulin - Improved Insulin sensitivity and reduction in Insulin levels, meaning body fat stores are more readily available to the body to use, enhanced energy metabolism and reduction to the risk of diabetes (3)
- Cancer prevention (4)
- Increased metabolism & ease of weight loss (5)
- Reduced Inflammation (6)
- Brain Health and slowing brain disease progression (7)
- Rodents have shown improvements in cognitive function including memory, motor function and leaning capacity during a period of intermittent fasting (8)
As evident by the above studies, Intermittent Fasting is a brilliant utensil for improving many aspects of ones health, in addition to this Intermittent Fasting may provide greater flexibility in combining restrictive diets with social commitments and also appears to improve mental clarity, focus and energy levels.
- Non Caloric beverages such as water, black Tea & Coffee are permitted during a fast and may even aid the fast by suppressing hunger.
- Non Caloric micro-nutrient supplements are encouraged during fasting, the absorption of these supplements may be increased during fasting periods, however, it is worth noting than fat-soluble vitamins will not be properly absorbed in the absence of food.
- Working out while fasted has been touted to enhance and ‘deepen’ the effects of a fast.
- Whilst most shoot for the 16:8 fasting method, studies show the onset of IF’s benefits from 12 hours onwards, feel free to work your way up.
- Intermittent fasting may not be for you, listen to your body and amend as necessary.