Does Intermittent Fasting Really Work?
We know that eating a whole, nutrient-dense diet is crucial for numerous aspects of health; from improving body composition and maintaining a healthy weight to decreasing the risk of disease and boosting mental health, food is a gateway for so many targets of wellness. However, while eating well is undoubtedly a significant foundation of health, there seems to be another addition that can be helpful – and that’s when you eat.
Most of us haven’t considered the timing of meals, per se. We know that in the morning, it’s time for breakfast, midday, we have lunch, and after work or school, we have dinner – with some possible snacks thrown in there as needed. This is where intermittent fasting comes into play for those looking to make some adjustments to their weight loss programming.
The Science
According to the Mayo Clinic, intermittent fasting essentially means that there is a set period of time within your schedule that you choose not to eat anything, whether for certain hours over the course of a day or specific days each week. A big trend within the fitness world at the moment, intermittent fasting has been shown to help decrease weight and improve overall lifestyle habits.
Fasting isn’t new; in fact, if you think back to our ancestors, most of them had to hunt and scavenge for food each day, which would take hours. There were no ready-made snacks or breakfast on the table upon waking! According to a review from the National Institute on Aging, several studies have shown us that intermittent fasting can decrease the risk of cancer, diabetes, certain heart conditions and even reduce the risk of obesity.
While it does appear that intermittent fasting aids in the weight loss efforts of many participants, one study from the International Journal of Obesity did note that it can also lead to being overly hungry – all of which can make intermittent fasting an approach that works for the short term, as opposed to a lifelong change of habits.
Benefits
Several benefits have been noted with intermittent fasting, but much more research still needs to be done to see the long-term effects of this type of caloric restriction. Always speak with your physician before attempting intermittent fasting – even if the benefits sound like they’re exactly what you’re looking for!
Decreased risk of heart disease: a review of several different trials was performed by Frontiers in Nutrition; compared to a regular diet protocol, intermittent fasting was noted to improve health markers that affect the heart and cardiovascular system, including cholesterol, insulin, and blood pressure.
Lowered risk of cancer: although most trials for intermittent fasting and its effects on cancer are limited, some studies done with rodents look promising.
Decrease in body weight: the International Journal of Obesity found that while more solutions should be implemented in a weight loss program that can be carried out long-term, intermittent fasting can be an option for those looking to lose weight.
Types of Intermittent Fasting
Typically, if you don’t eat anything after dinner (so let’s say nothing after 7pm) and then you don’t eat again until after 7am the next day, we could consider that intermittent fasting. Although this is only a span of 12 hours – and most intermittent fasting programs go for upwards of 16 hours with no food – if it is done consistently, then this type of pattern is what your body will get accustomed to. There are several different fasting methods to choose from; you’ll have to decide which one is best for you and your goals and lifestyle if desired.
5:2 Method
According to Hopkins Medicine, the 5:2 Method means that you are essentially eating like you typically would five days out of the week (i.e., Monday through Friday). Then, on the other two days of the week, you would only consume between 500-600 calories, or one meal each day.
Alternate Fasting Method
This method of intermittent fasting keeps things simple; the goal is to eat like you usually would one day, then fast the next day entirely. For example, you can eat like you typically would on a Monday, and then on Tuesday, you eat nothing. Wednesday, you eat like usual again, nothing Thursday, etc. Not quite sure if you can make it through an entire day without eating? This method can be tweaked with the addition of a 500-calorie meal on the “off” days. According to research from the American Journal of Clinical Nutrition, this might be a better way to do this type of fast over the long term.
16/8 Method
This method is very popular and highly customizable. With this intermittent fasting plan, you will eat like normal for an eight-hour span of time, then don’t eat at all the other sixteen hours. This could look like having your typical meals and snacks from 9am-5pm and not eating outside of that timeframe. However, maybe you work the night shift, so your hours need to change a bit – this could look like eating anywhere from 11pm-7am, then not eating again during the other hours.
Bottom Line
While the information available on intermittent fasting is promising in the realm of improving health and decreasing weight, there still needs to be much more research done. For example, one study observing alternate day fasting in women and men found that the glucose tolerance of the women in the study was negatively affected. Why the difference in genders? Only more time- and research – will tell.
As with any health trend such as the keto diet, there are always side effects and contraindications to fasting. Always speak with your physician if you want to give intermittent fasting a try to ensure this lifestyle change might benefit you and your specific health goals!