Even though intermittent fasting, also known as time restricted feeding, may seem like a relatively new term since it has become a popular trend over the years, the intermittent eating pattern has actually been around for centuries, and even plays a role in certain religions. Contrary to what some may believe, this type of fasting isn’t necessarily a diet. It’s a pattern that provides a set-eating window that allows your body to reset its insulin output and better burn fat storages for fuel. It also can come with a host of other health benefits such as regulating insulin levels, encouraging cellular repair, promoting gene expression to support longevity and more.
The human diet as we know it revolves around having 3 meals plus snacks each day, yet our bodies are actually designed for feast or famine. Before we even had ways to refrigerate food, our ancestors would fast during the day as they were hunting for their food, and then feast once it was gathered. And their metabolism increased as a result (1, 2)!
By providing your body with an eating window, normally eating just 8 hours per day from lunch to dinner, you may see big changes in your digestion and overall health -- in weight, cholesterol, blood pressure, glucose levels, heart rate, genetic expressions, inflammation markers, and more. The Body Ecology Immune Power Protein Shake can help to support blood sugar control, weight loss, and lean muscle gains.
Furthermore, with caloric reduction, there is an increase in appetite (in women, the hunger hormone ghrelin increases quicker (3)), a decrease in metabolism and it is not a sustainable form of eating long term (4). Intermittent fasting can basically address the long-term issue of insulin resistance and improve insulin levels, according to one study (5).
Time restricted feeding, whether you’re narrowing your eating window to 6, 8 or 12 hours, resets the hands of time and activates the genetics that are hardwired to save you.
Who is IF for?
Figuring out why you want to fast is an essential piece to this process. Usually the main reason people do IF is to lose weight and reset their body back to homeostasis. With certain health issues, fasting can have its benefits, as we’ll discuss.
You don’t want to do this if you’re not in good health or if you have a lot of stress in your life. We also highly recommend that if you do have any health issues that you speak to your practitioner (particularly someone who is specialized in nutritional genomics) prior to starting a fast.
The body essentially switches from burning sugar to burning fat when IF ensues.
Our insulin levels rise every time we eat, and any extra fat that hasn’t been burned off is directed into fat storages. Normally, your body burns through the sugar (carbohydrates) that is already stored in the body and uses it for fuel in between meals. When you fast, insulin levels drop and your body has to access these fat storages to burn them for energy.
Unlike caloric restriction where you can lose lean muscle mass, IF does the opposite. Refraining from eating for about 16 hours a day and eating in an 8-hour window burns the fat storages instead. And the fat storages are what provide the energy, not the protein in muscle.
Types of Time Restricted Feeding
Fasting Mimicking Diet
Created by fasting researcher, Valter Longo, this 5 day-per-month low calorie diet claims to enable the body to rejuvenate its cells and optimize its performance. The meal plan is low in carbohydrates and proteins and contains good fatty acids. After the 5-day period is completed, the consumer can resume a normal lifestyle/diet for the remaining 25 days of the month.
A water fast is just as it sounds. No food, just 2-3 liters of water daily for 24-72 hours. According to a recent small study, water fasting followed by a regeneration diet, reduced blood pressure, weight and oxidative stress. If you have certain health conditions however, we don’t advise you do this without medical supervision. Not that this is our first choice, yet staying hydrated during this type of fast would be essential. Taking small sips of water will allow your cells to obtain more water. Taking gulps just lets the water go right through you!
Created by Dr. Michael Mosley, this method is designed to cut calories to one-quarter, two days/week. So you would eat in between 500-600 calories, 2 days per week and eat normally the other 5 days, in no order.
One of the more common methods, 16/8 involves not eating after dinner, skipping breakfast and restricting your daily eating period to 8 hours. Then you fast for 16 hours in between.
This involves fasting for 24 hours, once or twice a week, for example, by not eating from dinner one day until dinner the next day.
Alternate Day Fasting
With the modified version of alternate day fasting, you eat normally one day and restrict your calories to 500 total the next day. And the following day, you go back to eating normal. The idea however is to not overeat on the days that you eat normally.
The Warrior Diet
According to this plan, you eat one meal at night, which is a feast. During the day, you can eat raw fruit and vegetables that are low in calories.
Protein Sparing Modified Fast (PSMF)
Normally used by those who are either obese or have a lot of weight to lose, the PSMF is a temporary diet designed to rapidly lose weight. This is a high protein, low calorie diet that eliminates carbohydrates and added fats, inducing ketosis. Unlike the keto diet that doesn’t focus so much on restricting calories, PSMF adopters eat 800 calories per day. This is not a diet to stay on long term since it will not provide adequate nutrition for the body.
There are many studies that actually show numerous benefits to these fasting methods to include the following:
Fasting can reduce oxidative damage and inflammation, which are usually indicators that can lead to premature aging. In one study, fasting reduced the body’s production of the insulin like IGF-1 hormone, which has been associated with aging and disease (6).
A decrease in C-reactive protein, which is a notable marker for inflammation, was reduced in the subjects of one recent study (6). Inflammation is linked with certain diseases, including heart disease and cancer.
Help Treat Diabetes and Heart Disease
Fasting may give the heart similar benefits resulting from exercise, such as improving blood pressure and lowering cholesterol (7). It can also help limit inflammation and improve sugar and fat levels in circulation.
Cellular Cleansing (Autophagy):
Also known as the cellular cleansing process, autophagy increases during a fast, which allows the body to essentially get rid of old cells and protein that the body no longer needs and new ones are created to replace them. It’s important to note that this process is something unique to fasting, and not caloric reduction. Diseases like Alzheimer’s and cancer can benefit from autophagy (8, 9).
Unlike diets that restrict the calories you take in, fasting actually increases metabolic rate, so the body is able to burn more calories (10). For some, an IF eating pattern can be easier to follow than a reduced calorie diet (11). When done correctly, if one doesn’t overcompensate on the non-fasting days, fasting for weight loss can work.
Promote Gene Expression to Support Longevity
Fasting can prolong longevity by protecting against genetic and environmental factors that otherwise contribute to the aging process and disease too (12).
What to Eat on Fasting Days
This isn’t an excuse to constantly eat chocolate bars every few days! That won’t help your body in the least. In Part 1 of our protein series, I talked about how to get the most out of your protein digestion. I also discussed how pea protein can regulate blood sugar to support healthy weight loss in Part 2, with the potential to encourage fat loss and muscle growth in Part 3. You’ll also learn how pea protein can have a drastic effect on the success of intermittent fasting in Part 4.
Nutritional Genomic Essential Summary:
Science is forever changing and studies are emerging that are undeniably proving the value behind time restricted feeding as something that can help with weight loss and treat and prevent certain diseases and health issues. Benefits to fasting include:
- Lowering inflammation
- Weight loss
- Cellular repair
- Anti-aging effects
- Prolonging longevity
- Treatment of diabetes and heart disease
It’s important not to struggle and to use a fasting method that you find works best for your body. Fasting may not be beneficial for everyone and should not be done if you’re planning to get pregnant, pregnant, breast-feeding, malnourished, underweight or have (or have had) an eating disorder.
As we always mention, there’s a front and back to everything. So just because IF may be a good option for someone, it may not be for someone else. Always consult with a trusted practitioner (especially someone literate in nutritional genomics) before starting something like this since they know your health better than we do!
- Patterson RE, Laughlin GA, Sears DD, et al. INTERMITTENT FASTING AND HUMAN METABOLIC HEALTH.Journal of the Academy of Nutrition and Dietetics.2015;115(8):1203-1212. doi:10.1016/j.jand.2015.02.018.
- Webber J, Macdonald IA. The cardiovascular, metabolic and hormonal changes
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- Catherine Gibbons,Phillipa Caudwell,Graham Finlayson, Dominic-Luc Webb Per M. Hellström Erik Näslund John E. Blundell. The Journal of Clinical Endocrinology & Metabolism, Volume 98, Issue 5, 1 May 2013, Pages E847–E855.
- Wegman Martin P., Guo Michael H., Bennion Douglas M., Shankar Meena N., Chrzanowski Stephen M., Goldberg Leslie A., Xu Jinze, Williams Tiffany A., Lu Xiaomin, Hsu Stephen I., Anton Stephen D., Leeuwenburgh Christiaan, and Brantly Mark L. Practicality of Intermittent Fasting in Humans and its Effect on Oxidative Stress and Genes Related to Aging and Metabolism. Rejuvenation Research. April 2015.
- Harvie MN, Pegington M, Mattson MP, Frystyk J, Dillon B, Evans G, Cuzick J, Jebb SA, Martin B, Cutler RG, Son TG, Maudsley S, Carlson OD, Egan JM, Flyvbjerg A, Howell A. The effects of intermittent or continuous energy restriction on weight loss and metabolic disease risk markers: a randomized trial in young overweight women. Int J Obes (Lond). 2011 May; 35 (5):714-27. Epub 2010 Oct 5.
- Min Wei, Sebastian Brandhorst, Mahshid Shelehchi, Hamed Mirzaei, Chia Wei Cheng, Julia Budniak, Susan Groshen, Wendy J. Mack, Esra Guen, Stefano Di Biase, Pinchas Cohen, Todd E. Morgan, Tanya Dorff, Kurt Hong, Andreas Michalsen, Alessandro Laviano, and Valter D. Longo. Fasting-mimicking diet and markers/risk factors for aging, diabetes, cancer, and cardiovascular disease. Science Translational Medicine.15 Feb 2017: Vol. 9, Issue 377, eaai8700.
- James E. Brown, Michael Mosley and Sarah Aldred. Intermittent fasting: a dietary intervention for prevention of diabetes and cardiovascular disease? British Journal of Diabetes and Vascular Disease,April 2013.
- Cataldo AM, Hamilton DJ, Barnett JL, Paskevich PA, Nixon RA. Properties of the endosomal-lysosomal system in the human central nervous system: disturbances mark most neurons in populations at risk to degenerate in Alzheimer's disease. J Neurosci.1996 Jan;16 (1):186-99.
- Hippert MM, O'Toole PS, Thorburn A. Autophagy in cancer: good, bad, or both? Cancer Res. 2006 Oct 1;66(19):9349-51.
- Zauner C, Schneeweiss B, Kranz A, Madl C, Ratheiser K, Kramer L, Roth E, Schneider B, Lenz K. Resting energy expenditure in short-term starvation is increased as a result of an increase in serum norepinephrine. Am J Clin Nutr. 2000 Jun;71(6):1511-5.
- Adrienne R. Barnosky,, Kristin K. Hoddy, Terry G. Unterman, Krista A. Varady. Intermittent fasting vs daily calorie restriction for type 2 diabetes prevention: a review of human findings. The Journal of Laboratory and Clinical Medicine. October 2014: Volume 164, Issue 4, Pages 302–311.
- Bronwen Martin, Mark P. Mattson, and Stuart Maudsley. Caloric restriction and intermittent fasting: Two potential diets for successful brain aging. Ageing Res Rev. Author manuscript; available in PMC 2009 Jan 13.
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