The question of fasting is a really interesting one that has literally been around for thousands of years. Some form of fasting has been part of religious and cultural traditions passed on through time. It’s only recently that researchers have unlocked the secret of fasting to be more than just a practice in terms of philosophy. We are now learning that almost any form of fasting has real physiological benefits to our health and longevity. One popular form of fasting is intermittent fasting.
What is Intermittent Fasting?
Intermittent Fasting (IF) is basically restricting the time that we eat every day to a certain number of hours. IF is not a diet, it is an eating pattern where we restrict the time we eat and expand the time we are not eating or fasting. Ultimately this results in a restriction of calories. Research in animal models has shown that even restricting the number of calories that we take in general can be helpful, but the fasting state where our body actually gets into ketosis, (going from burning sugar as our primary fuel to burning fat) shows increased benefits.
You may have been asked to fast to get bloodwork done at your doctor’s office, but now we are finding that intermittent fasting can have tremendous health benefits. Not eating anything past 8pm all the way to noon the next day and only eating between noon and 8pm has shown to lower cholesterol levels, lower blood pressure, lower blood sugar and even help with reducing weight. Adding a couple more hours have been shown to have additional benefits.
Usually, most fasting involves drinking plenty of water and can include tea as part of it as long as you don’t add anything that has calories to it during your fasting window.
What happens when you intermittent fast?
When we shift our eating patterns in a fasting direction, we notice several anti-inflammatory impacts throughout our body. Really what we can think about with fasting is that fasting works on both sides of the calorie equation. On the one hand, it boosts your basal metabolic rate or metabolism, increasing the calories that are burned. It also reduces the number of calories you take in and eat. This is because you will have less of an appetite, so you don’t eat as much and reduce your portion size automatically.
In recent years there have been some scientists that have won the Nobel Prize for their discovery of autophagy. This is the process of cleaning cellular debris and waste products that happens in our body at the cellular and metabolic levels during fasting. You can think of this as a metabolic “housecleaning” while we fast. What happens is that you are giving your body the rest it needs, giving it plenty of water but holding off on food so it can do all the very necessary repair processes. Cleaning out cellular debris, finding pre-cancer or early cancer cells and taking them out. Basically, keeping us healthy and working on all the anti-aging mechanisms that our bodies already have to keep us functioning optimally for longer. IF can also contribute to feeling better, having more energy, and potentially contributing to longer healthier life as we have seen in research with animals.
The research in humans is still early and ongoing on but there are definite benefits to Intermittent Fasting. If this is something that you would like to try for yourself, speak with your doctor to learn more about what an Intermittent Fasting plan would look like for you.
Dr. Shad (Farshad Fani Marvasti, MD, MPH) is a Stanford-trained medical doctor, associate professor in academic medicine, speaker, and author with expertise in nutrition and culinary medicine, wellness, public health and prevention.
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