How Intermittent Fasting May Help You Live Longer and Lose Weight
By Sarah Axtell, ND • June 21, 2017
Humans evolved in environments where food was often scarce, and therefore we developed many adaptations that enabled us to function at a high level, both physically and cognitively, when in a food-deprived or fasted state.
This is where intermittent fasting (IF) comes to play. IF is a pattern of eating in which individuals go an extended period of time (approximately 16 hours) without food. After that 16 hour fast, you can resume your normal eating regimen over the course of the next 8 hours.
After all, we are “feast and famine” organisms.
Here are the health benefits:
When you eat a meal you are in a fed state, or absorptive state, for 3-5 hours in which your body is working hard to digest and absorb food. During this fed state (high insulin state), it is difficult for your body to burn fat because insulin is ever-so-present. Insulin is the hormonal signal to the body to make and store fat.
But after the 3-5 hours in the fed state, your body enters the post-absorptive state, or fasting state (low insulin state). This state lasts 8-12 hours after a meal, and it is much easier for your body to burn fat because blood sugar and thus insulin has decreased. So if you are grazing and eating every 2 hours, you are constantly in a fed state and can never metabolically shift into the fat-burning state. But intermittent fasting is an approach that can promote this metabolic shift.
Preservation of Your Brain
If it wasn’t enough to convince you to do it for your waistline, try intermittent fasting to improve your brain function! Animal studies show that intermittent fasting can increase new brain cell production in the region of the brain responsible for memory. I know from personal experience when I do an overnight 16-hour fast, I have impeccable mental clarity.
Intermittent fasting has also been found to protect neurons by suppressing free radical production and cellular stress response systems that normally promote brain aging.
To prevent Alzheimer’s and Parkinson’s, consider intermittent fasting!
Reduced Risk of Cancer and Better Cancer Treatment Outcomes
Animal studies suggest that intermittent fasting may help prevent cancer. In addition, fasting may be a beneficial adjunct to chemotherapy, making it more effective. A short-term fast starves cancer cells and facilitates the chemo drug therapies to better target the cancer.
How to Do Intermittent Fasting
I recommend a 16-hour over-night fast 2-3 days a week. This means eating an early dinner (done by 7 pm) and not eating a morsel of food until 11 am the next day. You could certainly do this nightly but when first starting out, try it 2-3 days a week.
If this sounds too daunting, you could try fasting for a shorter period on a regular basis (ie. a 12-hour fast). Close the kitchen after dinner and don’t eat again until the next morning, approximately 12 hours later. For example, finish dinner at 7 pm and don’t eat breakfast until 7 am the next day. This will help you quit the night-time snacking that is compromising your waist-line, heart, longevity and brain. I know, I know…many of you reward yourself with food after the kids have gone to bed. But it is time to care for yourself in a different way- reading, castor oil packs, herbal tea, connecting with your partner, taking an epsom salt bath, watching a favorite show, and/or meditating are all good self-care options in the evening.
And remember when you are eating during the day, food quality still counts! You will likely not see results if you eat burgers, fries, pizza, bread and soda during the non-fasting period. Include anti-inflammatory foods, such as salmon, nuts, vegetables, berries turmeric, and grass-fed meat/poultry. Avoid or minimize inflammatory food, such as sugar, gluten (bread, pasta), potatoes, corn and cow dairy.
What about coffee or tea during a fast?
Coffee, herbal tea and water are all fine during a fast. Just don’t add cream or sugar as this would break the fast.
Is Intermittent Fasting right for you?
Intermittent fasting is worth trying, and if you feel good, continue! But if you do not feel well (shaky, weak, excessive hunger), then honor what your body is telling you and don’t do it. You may suffer from hypoglycemia and truly need to eat every 4 hours. Or if you have a history of an eating disorder, are underweight or are pregnant or breastfeeding, forgo intermittent fasting. There is no one-size-fits-all approach when it comes to nutrition. It is important to listen to your body. But if you do feel good with this approach to eating, it can be a really powerful tool to improve your health!
Nutritional strategies to optimise cognitive function in the aging brain: Wahl D, Cogger VC, Solon-Biet SM, et al. Ageing Res Rev. 2016;31:80-92. doi:10.1016/j.arr.2016.06.006.
Chronic Intermittent Fasting Improves Cognitive Functions and Brain Structures in Mice: Li L, Wang Z, Zuo Z. PLoS One. 2013;8(6). doi:10.1371/journal.pone.0066069.
Caloric restriction and intermittent fasting: Two potential diets for successful brain aging: Martin B, Mattson MP, Maudsley S. Ageing Res Rev. 2006;5(3):332-353. doi:10.1016/j.arr.2006.04.002
Fasting cycles retard growth of tumors and sensitize a range of cancer cell types to chemotherapy: Lee C1, Raffaghello L, Brandhorst S, et al. Sci Transl Med. 2012 Mar 7;4(124):124ra27. doi: 10.1126/scitranslmed.3003293. Epub 2012 Feb 8
Mitochondrial production of reactive oxygen species and incidence of age-associated lymphoma in OF1 mice: effect of alternate-day fasting: Descamps O1, Riondel J, Ducros V, Roussel AM. Mech Ageing Dev. 2005 Nov;126(11):1185-91.
Fasting-Mimicking Diet Reduces HO-1 to Promote T Cell-Mediated Tumor Cytotoxicity: Stefano Di Biase, Changhan Lee, Sebastian Brandhorst, et al. Cancer Call. 2016 July 11.
Editor’s Note: The information in this article is intended for your educational use only. Always seek the advice of your physician or other qualified health practitioners with any questions you may have regarding a medical condition and before undertaking any diet, supplement, fitness, or other health program.