The number of ways that have been created to help people lose weight is simply mind-numbing. All sorts of whacky tips, tricks, diets, and workouts have been published, but the vast majority of them are all junk.
However, a new eating protocol has gained momentum in the last few years that seems to actually have some sound science backing it as an effective way to speed weight loss and improve overall health that won’t leave you feeling starved.
We’re talking about Intermittent Fasting.
What was once a diet reserved only for hardcore crossfitters has exploded in popularity and is now embraced from all walks of life — including Hollywood stars and bodybuilders.
But how does Intermittent Fasting work and can skipping meals actually be healthy?!
Let’s find out!
What is Intermittent Fasting?
Intermittent Fasting (IF) involves cycling between periods of feasting and fasting (i.e. eating). Basically, you are choosing to avoid eating during a certain period of times each day, and only eating during a predetermined window of your choosing.
Seems a bit odd doesn’t it?
Well, consider this — fasting is one of the oldest practices in the world. Numerous cultures have embraced the practice of fasting for a number of reasons, and some religions still embrace the practice to this very day!
But how does this enhance fat loss?
We’ll get into that next!How Intermittent Fasting Boosts Fat Loss
Body fat is the way your body stores energy. This dates back to our caveman days, when food was scarce and our bodies would turn to our fat stores as a source of fuel to keep powering the numerous metabolic processes required to keep us alive.
So, some fat is needed from a pure survival point of view, but too much, and well, you end up looking like the Michelin baby on TV!
Now, how exactly does intermittent fasting help fat loss?
Well, when you go without food for an extended period of time (> 8 hours) the body changes a few things to access your stored energy (i.e. fat) more efficiently. Basically, the body alters certain functions of the nervous system, and tweaks some major things with several important hormones:
When we eat, insulin levels increase to deal with the incoming glucose load (in the forms of carbs). When we fast, insulin decreases significantly — which support fat burning.
- Human Growth Hormone (HGH)
Human Growth Hormone is an incredibly anabolic (muscle-building) hormone that triggers growth, cell reproduction, and regeneration in mammals. It is also a stress hormone which mobilizes glycogen and free fatty acids for energy during times of duress.
Fasting has been well documented to significantly elevate levels of HGH, as much as 5 times normal levels![2,3] Benefits of the increase in HGH includes greater fat loss and muscle gain, in addition to a number of other interesting functions.[4,5,6]
Norepinephrine, a.k.a noradrenaline, is a hormone / neurotransmitter the nervous system releases to get the brain and body moving in a hurry. It’s at its lowest levels during sleep, and highest during times of stress — the “fight or flight” response.
Your nervous system sees fasting as a stressor, and in response, it shuttles norepinephrine to your fat reserves, which signals fat cells break down into free fatty acids which are then used for energy.[7,8]
Now let’s see what kind of benefits these hormonal changes give to a person living the Intermittent Fasting lifestyle!Intermittent Fasting Benefits
The resulting hormonal changes initiated by IF result in some pretty cool effects including:
- Higher metabolic rate
- Increased fat oxidation
- Lower levels of inflammation
- Greater brain-derived neurotrophic factor (BDNF), which supports brain health
- Increased life span
- Improved insulin response
- Reduced risk of Type 2 Diabetes
As you can see, not only is fasting great for weight loss, it’s also incredibly good for your overall health![9,10]
Why Intermittent Fasting Helps Fat Loss
The primary reason intermittent fasting supports weight loss is that it ultimately helps you eat fewer calories during the day. Not eating for the first part of the day makes your body rely on its stored fat for energy, turning it into a “fat burning” machine!
This is one of the primary reasons IF is so popular for weight loss.
Additionally, when people are dieting and tend to eat 5-6 smaller meals, they may never feel really satiated or “full” following a meal. IF allows you to eat 2 or 3 bigger meals which can be more satiating and help you avoid blowing your daily calorie “budget.”
Getting used to IF can take some time though, especially if you’re a breakfast person. After a couple of days though, your sympathetic nervous system (fight or flight system) kicks into gear and with it comes decreased appetite, heightened alertness, and greater focus — all valuable qualities to have when dieting.
Yet, some will still have hunger cravings pop up from time to time, and on those occasions having an effective fat burner can be your saving grace.Best Intermittent Fasting Fat Burners
Fat burners are a great aide during intermittent fasting, as they are calorie free, which means they won’t break your fast. Plus, they’ll also help squash any pesky hunger cravings you might get during your fast. The key is to find an effective fat burner, and we’ve got three of the best fat burners around:
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2. Ho KY, Veldhuis JD, Johnson ML, et al. Fasting enhances growth hormone secretion and amplifies the complex rhythms of growth hormone secretion in man. Journal of Clinical Investigation. 1988;81(4):968-975.
3. Hartman ML, Veldhuis JD, Johnson ML, et al. Augmented growth hormone (GH) secretory burst frequency and amplitude mediate enhanced GH secretion during a two-day fast in normal men. J Clin Endocrinol Metab. 1992;74(4):757-765. doi:10.1210/jcem.74.4.1548337.
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12. Heilbronn LK, Smith SR, Martin CK, Anton SD, Ravussin E. Alternate-day fasting in nonobese subjects: effects on body weight, body composition, and energy metabolism. Am J Clin Nutr . 2005;81(1):69-73. http://ajcn.nutrition.org/content/81/1/69.abstract
13. Johnson JB, Summer W, Cutler RG, et al. Alternate Day Calorie Restriction Improves Clinical Findings and Reduces Markers of Oxidative Stress and Inflammation in Overweight Adults with Moderate Asthma. Free radical biology & medicine. 2007;42(5):665-674. doi:10.1016/j.freeradbiomed.2006.12.005. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1859864/
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