Fasting is when you voluntarily go for a period of time without food. It has been practiced by every culture in every country over the course of thousands of years. Sometimes it’s been used for spiritual renewal, other times for political protest, and often it’s been used for health reasons.
Those who are for it point to the fact that it gives a much-needed break to a number of bodily systems that are habitually stressed by the process of digestion. It also allows the liver to play catch up, disposing of AGE (advanced glycation end) waste products; and it cleans out your insides, so that you can make better use of the nutrients that you consume.
Those who are against fasting say that the body is able by itself to take care of disposing of toxins during sleep; that fasting depletes the body of protein and calcium, leading to muscle loss and osteoporosis; and that it slows the metabolism, resulting in more rapid weight gain once the fast is ended.
Research on animals has shown that a restricted-calorie diet increases longevity. Now there is evidence that intermittent fasting combined with eating fewer calories can lead to a longer, healthier lifespan for humans, too.
What Is Intermittent Fasting?
Simply put, it’s a pattern of eating where you alternate between periods of fasting and non-fasting.
Why Is an Intermittent Fast Better than a Traditional Fast?
1. It’s easier to stick with.
You get a mental break since you’re not dieting 24/7
During non-fasting times, you eat what you enjoy. You are not following a “diet”.
It's an easy way to restrict calories
2. Shorter duration means:
Your metabolism doesn’t slow down
You don’t get into starvation mode
You don’t stay on it long enough to have reduced energy
Benefits of Intermittent Fasting
Study after study has found beneficial effects of intermittent fasting in animals:
Reduced serum glucose
Reduced insulin levels
Enhanced cardiovascular and brain functions
Improvement of risk factors for coronary disease and stroke
Reduced blood pressure
Improvement in LDL cholesterol levels
Reduced incidence of cancer
Resistance to age-related dementia
Increase in lifespan
A 2006 animal study found that eating less-than-needed alternated with eating more-than-needed prolongs life. In the human level, researchers from Louisiana State University, the University of New Orleans, and the Stanford Medical School in California observed health benefits starting as soon as two weeks after beginning an alternate day fasting program. In their summary, the team hypothesized that in addition to mitigating a long list of afflictions and diseases, the intermittent fasting pattern of eating could prove to be an effective way to control weight.
Rodents were restricted to eating only 20 to 50% of their necessary daily calories one day, and allowed to eat as much as they liked the next day. Researchers saw an improvement in insulin resistance, asthma, allergies, infectious diseases of all kinds, autoimmune disorders such as rheumatoid arthritis, cardiac arrhythmias, osteoarthritis, and more. The animals were more resistant to the effects of acute stress, and their cognitive ability was improved.
Further, it has been discovered that BDNF levels are increased. Brain-Derived Neurotrophic Factor is a chemical known as a neurotrophin. Although most neurons in a mammal’s brain are formed before birth, there are parts of the adult brain that can grow new neurons if there are neurotrophins present. When BDNF is injected into test animals, their insulin sensitivity is improved and they begin to lose weight. There are other benefits too. Humans with high BDNF have lower depression levels, and increased BDNF makes you smarter. So BDNF is a very good thing, and one simple way to increase it is through intermittent fasting.
How Do I Begin Intermittent Fasting?
There are many different intermittent fasting protocols, but there are three methods that are the most popular.
1. The Daily Fasting Method:
On this diet, you only consume food during certain hours of the day. One popular variation of this method is known as the Fast-5 Diet. No foods are prohibited, but food must be consumed exclusively during a five-hour window, for instance from 5pm to 10pm. The 19 hours of continuous fasting is the key to the diet’s effectiveness, keeping the digestive tract empty for long stretches of time, and reducing insulin levels. On this diet, don’t expect results until the third week, at which time you should begin losing about a pound per week.
2. The “Eat Stop Eat” Method:
Regular food consumption is punctuated by one to three days per week devoted to fasting and exercise. On fasting days, you consume nothing but water and black coffee. In order to lose one pound of body fat, you must burn 3500 calories. By eating normally during the week and then fasting for one or more days, you cut down on your weekly caloric intake by 1500 to 3500 calories.
3. Alternate day fasting:
As the name suggests, this is one day of eating and one day of fasting. One easy way to do the alternate schedule is to start your fast after an early dinner, say 6 pm. Then you don’t eat until the next day at 6 pm, at which point you have dinner. With this technique, there is no day where you go entirely without food. That’s an easy way to ease into intermittent fasting, so that you can have all of the weight loss and health benefits, while minimizing the dread of the upcoming fast.
In closing, intermittent fasting combined with proper nutrition can be a very powerful way not only for safe weight loss but also for dramatic improvement of overall health and even extension of lifespan.