Should You Try Intermittent Fasting?
It’s usually around this time of year, when we have exceeded our quota for cheese and chocolate, that we start thinking towards the new year and ‘fresh start’ we’ll take with our diet to drop these few extra holiday pounds.
If you’ve spent anytime Googling “diets that work” you may have come across things like “5:2”, “Warrior Diet,” or “16:8” – diets all rooted with the same premise – introduce a period of intermittent fasting into either your daily or weekly routine.
Is intermittent fasting (IF) right for you? As interest in this way of eating has increased, we’ve received more and more questions about it here in #ReflexNation. So, we went to our experts to get inside scoop to help you make informed choices about adding IF to your life.
Where Did IF Start?
Fasting isn’t anything new. For thousands of years, people have fasted either due to food scarcity (the struggle to hunt for that buffalo is real) or for religious reasons.
In the 1930’s researchers discovered that significantly reducing the caloric intake of lab rats helped them live longer and have few age-related diseases.1
Today, while most of the research around calorie restriction and fasting has been conducted on animals, we are starting to see more promising (albeit still early) research breakthrough in human models.
What exactly is IF?
IF is fasting, but not continuously. There are different approaches to it (which we’ll discuss in a second), but the overall idea behind it is that you can eat your ‘regular’ diet most of the time, while restricting yourself the rest. Think of this like chronic cardio vs. HIIT. While typical dieting restricts food quantity or certain foods or food groups for long periods of time, this approach is more intense, but only for a short time.
What Are the Purported Benefits of IF?2,3
- Weight loss
- Reduced cravings
- Improved biomarkers of disease (LDL cholesterol, triglycerides, blood pressure)
- Reduced oxidative stress
- Preserved learning and memory
- Improved insulin sensitivity
How Does IF Work?
It is still not 100% clear what the mechanism of action is for IF. One hypothesis is that it puts the cells of your body under mild stress. Think of it like exercise (another stress to the body) – the more you do it the fitter you get. The more we stress our cells, the more they adapt to that stress and become more efficient at what they do.
Another theory is that the period of fasting gives your body a chance to burn fat as fuel. If you don’t eat for 10-16 hours, your body goes into its fat stores for energy.
What is the Current Research Supporting IF
IF holds promise for improving body composition, decreasing fat mass, while maintaining lean tissues; especially when combined with resistance training.4 A benefit for all of those looking to shred. It also appears that IF improves insulin sensitivity, stress resistance and overall lifespan, as well as cognitive function and appetite control.5,6
You may be thinking ‘whoa’ – sign me up. But remember there is still quite a bit of research to do on the topic. Some of these benefits have only been seen after longer periods of fasting (20-24 hours) and are dependent on your activity level during the fast. As John Berardi or Precision Nutrition notes, the more sedentary you are, the longer you may have to fast to get results. IF is not a replacement for a good ol’ sweat session.
What Are the Different IF Approaches?
5:2 Diet (aka The Fast Diet): this form of IF lets you eat what you want five days of the week, while fasting the remaining two by restricting your food intake to around 500-600 calories.
16:8 Diet: this approach has you fasting every day, restricting eating to just 8 hours while fasting for 16. Many people like this approach as it really requires only ‘missing’ one meal. If you eat your dinner by 7 PM, you can consume your next meal at 11 AM the following day.
Warrior Diet: the most restrictive diet concerning time spent eating, this type of IF focuses on ‘underfeeding’ for 20 hours of the day (includes time spent sleeping) followed by four hours of ‘overfeeding’ at night. The idea is that by only consuming light foods during the day (think whey protein, bone broth or small portions of fruits and veggies) while consuming a nutrient dense dinner you are aligning your eating patterns with your circadian rhythms.
So, Should You Try IF
Here’s the thing. There is a lot of promising research on IF, and even more anecdotal evidence about how IF has helped people drop fat, think clearer, and reduce cravings, without really changing the types of food they are eating all that much.
But IF isn’t a shortcut. If you have poor eating habits or are looking for a crash diet to drop pounds fast, this isn’t the program for you. Fasting puts a stress on your body, and you have to have a foundation of good nutrition, exercise, stress management and proper sleeping habits to deal with that.
There is also a misconception that since no food is technically off limits that you can eat whatever you want when you’re not fasting. While many people feel IF is a more flexible approach to dieting as the restriction period is much shorter, this isn’t a ‘have your cake and eat it too’ approach. Healthy, whole foods, people – there is no escaping it.
Who Should Not Do IF
IF is not for the following groups of people:
- Pregnant or Breast Feeding
- Those eating a poor diet
- Those who have suffered from an eating disorder or disordered eating
In #ReflexNation, we always advise that anyone looking to start a new diet or supplement plan check with their healthcare practitioner first to make sure it is right for them.