It feels like every year there is a new diet or nutrition trend that hits the papers. Once it hits, marketing companies, fitness and nutrition companies get together to figure out how they can monetize off this latest finding.
Intermittent fasting, however, is described as early as the bible and was re-introduced in the early 1900's as a suggested way to help overweight and obese individuals lose weight.
Over the years, research has slowly evolved from animal studies to human studies; particularly with regards to type 2 diabetes. While research has shown some success for those who have been diagnosed with type 2 diabetes, I always encourage speaking with your doctor, dietician or nutritional coach before starting any nutrition program.
Unfortunately, this is where most of the human research has stopped. And, per usual, women are not the ones being studied. Recent research has began to discover that intermittent fasting may help women in their peri-menopausal, menopausal and post-menopausal years avoid or reduce the dreaded night sweats/hot flashes. Outside of this, however, the scientific community has fallen short on evidence of success for women. In studies conducted with men, we do see a small success rate of intermittent fasting. Therefor, I stick with my good old "tried and true" with clients: if you want to try it, it is something you feel you can sustain life-long and it works for you, go for it!
Before we move forward, please note that this is much more complex that what you will read below. This is the very top layer of what intermittent fasting is and how it can possibly be of benefit to you or a loved one.
Now, what is intermittent fasting and is it something you should explore in your fitness and nutrition journey?
Intermittent fasting
Intermittent fasting is, in it's most general sense, the amount of time between eating or drinking anything with calories or nutrients. For example, most of us already intermittently fast when we go to bed. If you eat dinner at 7pm and eat nothing until breakfast the following morning at 7am, then your fasting period is 12 hours. Technically, if you drink coffee with creamer at 5:30am, you will also break your fast at that time due to the calories in your creamer.
Theories also suggest (and some studies are beginning to show) that fasting can also help regulate hormones. This is something that I am personally hopeful the scientific community begins to explore on a deeper level with peri-menopausal, menopausal and post-menopausal women.
Keep in mind, many of these studies and research have been conducted on animals, men (because lets face it: women's hormones are more challenging to track since we are all so significantly different) and young children and adults. During much of the research, there is one ingredient that appears to hold true for the scientific world: eating during your sleeping hours increases your risk of weight gain and obesity (among other diseases). In addition, if you are not getting enough sleep, or are waking up to eat in the middle of the night, this can lead to increased insulin resistance and to type 2 diabetes.
Is Intermittent fasting right for me?
When it comes down to it, if you eat within a specific window of time, you'll likely experience weight loss because you are consuming fewer calories. Calories in, calories out will always be the way our bodies work; but testing the waters to see what window of time is best for you is a great way to start!
If a client is interested in trying intermittent fasting, I have them start by using a 12-hour window. Pay attention to the first time you take in calories in the AM and eat within that 12-hour window. If you do well with this for a week and feel it is sustainable, drop off another hour and eat within an 11-hour window. I generally do not recommend under an 8-hour window (especially if you exercise; you need that fuel for the workout itself and for recovery!); but some find benefit in a smaller window of time 1-2 times a week. If you are new to intermittent fasting but would like to try it, I would highly encourage meeting with a certified nutrition coach or dietician to help you along the way.
Keep in mind that you cannot eat anything you want during that window of time! You will still need to be mindful of your calorie and macro (carbs/fat/protein) content. Stuffing yourself during an 8-hour window will not lead to positive results but rather to weight gain if you consume more than you expend.
Remember to ask yourself if this is sustainable for the remainder of your life. Because weight loss and gain over and over again is harder on the body than losing the weight long-term. If you feel that a 12-hour window is sustainable for you most days of the year, give it a try and see how it fits for you!
If you want a more detailed and guided tour and support of intermittent fasting, reach out to a certified nutrition coach or dietician who has the knowledge to guide you.
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