Fasting, the complete abstention from food and beverages other than water, has been practiced for millennia because of its physical and spiritual benefits, as well as out of necessity in times of food scarcity. Positive effects of fasting include initiating cellular repair, reducing inflammation and lowering blood pressure and glucose. Fasting also increases longevity, prevents cancer and reduces neurodegeneration.
Despite the numerous benefits, people are often reluctant to engage in fasting due to the discomfort of being hungry, the loss of muscle mass when practiced on a prolonged basis and the inconvenience of reduced energy to accomplish daily tasks. A growing body of evidence shows that fasting or restricting calories just 1-2 days per week can jumpstart your metabolism and provide many of the benefits of a longer fast without the unpleasant side effects.
One way to ease into fasting is to choose one or two days per week to refrain from eating. You may eat as much food as you like on the other days of the week but you should, of course, make healthy food choices. For people with a significant amount of weight to lose, fasting every other day is a recommended strategy. This is called intermittent fasting and is a good choice for people who find it difficult to adhere to a low calorie diet. If you follow this routine regularly, hunger will diminish on fast days once your system gets used to it.
Calorie restriction follows the same pattern as intermittent fasting, but instead of abstaining from food entirely, you eat 500 calories 1-2 days per week. You can achieve this by skipping breakfast and only eating in the afternoon and evening, resulting in a fast of approximately 16 hours. Contrary to expectations, research shows that people do not binge on food following a calorie-restricted day, so calorie intake overall is lowered.1
Short-term fasts induce a mild stress response which is beneficial to the body, unlike chronic uncontrolled stress. It is likened to plants producing more antioxidants when they are exposed to drought. In humans, the changing nutritional conditions result in less visceral fat, increased human growth hormone and lowered inflammatory markers such as homocysteine and C-reactive protein. This translates into a higher resting metabolic rate and less foundation for disease.
Intermittent fasting is safe to undertake without supervision for generally healthy adults. People in weakened states of health should not fast without first consulting a health care practitioner.
Dr. Jessica Needle is a naturopathic doctor practicing at Optimal Health Center in Palm Desert and can be reached at (760) 568.2598.
Reference: 1) Klempel MC et al, Nutr J. 2010 Sep 3;9:35. doi: 10.1186/1475-2891-9-35.