New Years mean new resolutions, new goals, and new reasons to be a better you. Diet and exercise fads come and go every year; some you may have tried, others you have skipped. Cleanses, HIIT, soup diets, Crossfit, Atkins, the list goes on.
One approach increasingly supported by health and fitness professionals is Intermittent Fasting. If you are looking to restart your body, kick-start your metabolism, and train your body to be better, more efficient, and more effective, then maybe an Intermittent Fasting diet is for you. Studies suggest that controlled, careful, responsible fasting may decrease blood sugar, maintain muscle, and even increase lifespan.
Whether you are simply curious about the connections between fasting and weight loss or want to know the best way to start Intermittent Fasting, we have gathered all the best advice and guidelines below to answer your questions and help you decide if Intermittent Fasting is the right diet choice for you.
What is Intermittent Fasting?
Intermittent Fasting is, first and foremost, a scientific approach to helping your body efficiently use calories. You may have heard of all sorts of “fast dieting,” trendy, modified fad diets that try to compress the scientific benefits of Intermittent Fasting into something quick and easy for pop culture consumption. Intermittent Fasting is not about binging, starving, or going to extremes, however. It is simply an approach to health that considers how our food choices can actually strengthen the building blocks of our body.
As early as 2005, scientists at the National Institute on Aging, a division of the NIH, identified the benefits of intermittent fasting. Lead NIH scientist Mark Mattson summarized the broad benefits: “During the fasting period, cells are under a mild stress and they respond to the stress adaptively by enhancing their ability to cope with stress and, maybe, to resist disease… There is considerable similarity between how cells respond to the stress of exercise and how cells respond to intermittent fasting.” In other words, we work our muscles when we exercise, so why not work our cells when we diet? A little physiological stress can be a very good thing.
Studies followed testing how controlled, Intermittent Fasting impacted the body’s response to stress. Could fasting decrease the stress-response of insulin production? Yes. Could intermittent fasting impact asthma symptoms, another sign of inflammation in the body? Yes. Repeatedly, scientists found connections between carefully controlling the nutritional stress to the body and reduction in the body’s stress response. This often led to weight loss and an increase in overall health.
In comparison to fad diets that put people at risk of poor nutrition by subjecting the body to unhealthy extremes, Intermittent Fasting might best be described in the words of Dr. Stephen Freedland, of the Duke University Medical Center. He identified the effective combination of calories and caloric intake as “undernutrition without malnutrition.” Intermittent Fasting helps our bodies find that balance.
Fasting is good for your cells
Think of Intermittent Fasting as a HIIT workout for your cells. Fasting triggers a biological process called “autophagy.” This basically means that the cells begin to self-recycle, breaking down at the mitochondrial level, removing toxins and stabilizing molecular structure. This “house cleaning” process works much the same way that breaking down muscle fibers in a strong, intense workout leads to stronger muscles over time.
Scientists are not sure exactly why certain aspects of cells are targeted for particular types of “cleaning.” Sometimes autophagy results in the body removing damaged and decayed parts of the cellular structure; other autophagic actions lead to the strengthening of cell walls or the increasing in antigen production. In all cases, we know that autophagy is an essential cellular process in the human body.
Recent studies sponsored by the National Cancer Institute investigate the links between cancer and a reduction in cellular autophagy in the hopes of reversing the process: increasing autophagy to combat cancerous cells. Since this cellular process links to direct health benefits, scientists see potential in controlling autophagy to reduce all types of negative, biological outcomes, including epilepsy, diabetes, Alzheimer’s disease, and obesity.
When fasting, we send signals to our body that no additional nutrition will be coming in, so anything unnecessary in the body needs to go out. The body generates autophagosomes (think of them like molecular-level trash bins) that target cellular components identified as reducing overall efficiency. At the end of the process, cells are stronger and healthier, and the body is renewed as a whole.
Fasting for too long means the body will target cellular components that are working well, thus reducing overall health. This is why binge diets and other extreme approaches to food consumption fail. But by engaging in careful Intermittent Fasting, the hope is to turn on autophagy long enough for some biological “Spring Cleaning” and then to turn off the process by eating healthy foods that replenish the cellular structure with quality nutrients. The molecular damage is brief and limited to the parts of your body that needed a little self-recycling in the first place.
Benefits of Intermittent Fasting
As we have seen, Intermittent Fasting targets physiological and neurological inflammation at a molecular level. Although the long-term benefits are still under study, the fundamental benefits of the autophagic process are clearly applicable to people looking to live longer, healthier lives. As with any diet, Intermittent Fasting is most effective in combination with a responsible, consistent exercise program that includes both cardio and strength training.
Lose Stubborn Belly Fat
When we fast and our body begins to repair itself, one of the first things that happens is a healthy reduction in insulin levels.
Insulin is a hormone produced by the pancreas that helps the body use carbohydrates and sugars as energy, the “calorie burn.” Too many carbs and sugars (or too often) and instead of burning fat, the body stores it, often right around the middle. The more fat is stored, the more insulin the body produces to try to use it, but the less effective that insulin becomes. A vicious cycle begins. Increased insulin levels are directly connected to diabetes, obesity, and cardiovascular disease, to say nothing of how excess carbs and insulin production make you feel: sluggish, tired, and cranky.
If we allow our body to take in carbs correctly, however, and reduce our overall intake of them, the insulin in our bodies works correctly, burns fat effectively, and healthy autophagy increases. Our insulin resistance decreases, as does that “stubborn belly fat.”
Studies have shown that lengthening the time between meals allows the insulin in the body to drop into an optimal “fat-burning” range. This means that a strategy of Intermittent Fasting, periodically targeting the time between meals, gives the body time to recover and regulate those insulin levels.
Remove (Molecular) Toxins
Intermittent Fasting is NOT a “detox.”
Intermittent Fasting triggers autophagy; the process of autophagy, as we now know, includes the removal of toxins and molecular byproducts at a cellular level. Thus we see a direct correlation between responsible Intermittent Fasting and reducing toxins in our body. Our body works more efficiently, heals itself correctly, and weight loss occurs naturally.
The connection between Intermittent Fasting and toxin reduction, however, can lead to false or overstated claims that it is “detoxifying” the body of such products like alcohol, environmental toxins, or second-hand smoke. Such ideas misunderstand how Intermittent Fasting works and lead to harmful, extreme eating/fasting routines that may result in long-term, negative impacts to your health.
A recent study at the Yale School of Medicine identified new ways in which Intermittent Fasting changes how the body responds to inflammation. Beyond allowing the body time to regulate insulin levels, the new study showed that fasting prompts the body to produce a chemical specifically to reduce inflammation. This “metabolite” appears in the bloodstream in response to the type of caloric reduction in Intermittent Fasting as well as high-intensity exercise. It inhibits the inflammatory response of genes that are linked to autoimmune diseases and autoinflammatory disorders.
By actively engaging in Intermittent Fasting, we increase this anti-inflammatory response, decrease inflammatory action, and potentially reduce our risk of diseases like atherosclerosis, rheumatoid arthritis, and Alzheimer’s.
Aging is, quite simply, the inability of the body to effectively recover from damage. As we age, it takes longer for our bodies to bounce back from a hard workout; or a broken bone takes longer to heal. Neurologically, our memory declines as neurons don’t work as efficiently as they used to and the body can no longer quickly repair the decline. As our skin cells break down, we see wrinkles, grey hair, and “age spots.”
At a molecular level, autophagy slows down or stops altogether. Mitochondrial networks fragment and the aging process accelerates. A recent Harvard study, however, has shown that controlling mitochondrial decay through intermittent fasting actually fuses the cellular structure back together, essentially making the cell “younger.” By proactively engaging in Intermittent Fasting cycles, we can slow down the aging process of our cells and age slowly and gracefully.
How Do I Start?
Once you have decided that a diet relying on Intermittent Fasting may be right for you, where do you begin?
Start with an easy question: how many meals a day should I eat? The answer is three, right? Or is it six now? According to evolution, is there even a correct number? In fact, there’s not! Once we get past the idea that regulated daily meals are a cultural structure, figuring out the right amount of calories to consume can become a strategy, not a compulsion. We can listen to our body, know how it is going to respond, and build an Intermittent Fasting cycle that works for our life.
What Do I Eat?
Your Intermittent Fasting plan should be centered on a healthy, well-rounded meal plan. Intermittent Fasting does not mean you eat cheeseburgers and beer for a few days and then nothing the next. It means following a nutritional plan that is generally rich in vegetables and protein, and low in processed foods and carbs. And, of course, this should all be accompanied by an exercise plan that includes cardio and strength training several days a week.
As with any dietary decision, Intermittent Fasting is not a one-size-fits-all solution. The following patterns have proven effective for many people, but it is up to you to choose what works for you. Also, make sure to consult a fitness professional to help determine what’s right.
Many advocates of an Intermittent Fasting plan adhere to a 16-hour cycle where they eat their meals in an 8-hour window and then take 16 hours “off.” This can be surprisingly easy to adapt to if you are already someone who skips breakfast!
The benefits of such an approach include a consistent schedule, “training” your body daily and learning to handle the hungry feelings that come from long periods without eating. It is the Intermittent Fasting cycle of choice for Mark Mattson, the lead scientist at the National Institute of Aging, for example. And this plan is also supported by recent studies that suggest working out on an empty stomach.
16-hour fasting can be difficult to start with, however, as it can take some time to adjust to the daily schedule.
The most popular diet that encourages a weekly fast is the 5:2 Diet, devised by a British biologist and popularized in Hollywood by the likes of Jimmy Kimmel and Benedict Cumberbatch. This plan calls for 5 days of regular, healthy calorie intake followed by two days of 500 calories.
While 2 days of minimal calorie consumption may seem like a long time, in many ways, this Intermittent Fasting plan is less intensive than the 16-hour cycle. It has caught on because many people find it manageable to eat a light meal 2 days in a row, knowing that they can return to regular meals for the rest of the week.
Studies at the USC Longevity Institute suggest that fasting 2 to 5 days a month produces many of benefits of daily or weekly Intermittent Fasting. In this plan, participants commit to a cycle that includes two to five days of reduced calorie consumption, typically around 700 calories each day, before returning to their regular healthy diet. Like the daily approach to Intermittent Fasting, this plan can trigger more distracting hunger pangs, as the “fast” lasts for up to 5 days; like the weekly approach, this diet approaches fasting as a reduction in calories, not a complete elimination of food for any period of time. It tries to effectively balance the best of both shorter ideas.
The benefits of all three of these Intermittent Fasting cycles are the same, with dieters noticing a reduction in waist circumference and weight, lower insulin levels, and potential reduction in cancer rates. It is up to you to decide if such a diet works in your life and, if so, which approach you can commit to. You should, of course, consult with your doctor before radically altering what you eat, but Intermittent Fasting may be a good discussion to have.