‘Diet.’ The word conjures up feelings of restriction and deprivation, right? Ugh. But, stay with us here.
Usually, diets are all about restricting the amount or type of food we eat. Intermittent fasting (IF) is about restricting the times we eat, essentially, scheduling your mealtimes to get the most out of them and kick unhealthy eating habits.
It has nudged ‘Paleo’ and ‘Keto’ diets out of the top spot as the world’s most trendy health and fitness regime, and has garnered a swathe of celebrity endorsements and thousands of testimonials from happy adopters online.
Lose weight, improve your overall health, simplify your life and live longer. All this while eating all the foods you usually eat! Too good to be true? Let’s dive in, and see if this health trend is deserving of the hype.
It’s All About Timing
First things first, ‘The IF Diet’ isn’t so much a diet as a pattern of eating. The suggested patterns vary, but it’s all about cycling between periods of eating and not eating. Here are the most popular options:
- 16:8 – Probably the most popular pattern, which allows you a daily ‘window’ for eating set at 8 hours, and the rest of the time – half of which you’ll likely be sleeping for – reserved for fasting.
- Eat Stop Eat (aka Alternate Day Fasting) – With this one, you fast for 24 hours, twice per week. That’s all there is to it (this may be the definition of “easier said than done”!)
- 5:2 – This pattern is based on eating around 500 calories on two non-consecutive days, but eating as you usually would on the other days of the week.
The ‘Fed State’
So why the weird time combinations? Well, when you dig into the literature on the IF diet, you’ll come across the term ‘Fed State,’ which is the time your body is digesting and absorbing nutrients from food (around 2-5 hours after eating.)
The advantages of the IF diet come from the idea that because insulin levels are high during the fed state, it’s not easy for the body to burn fat. After this period, when your body is not processing food, you are in the “postabsorptive state” (around 8-12 hours after your last meal), and finally, you reach the “fasted state,” when insulin levels are low and that fat that was inaccessible before can now be burned.
With regular eating schedules, we rarely reach this fasted state, where insulin levels drop to make stored fat more accessible. But it’s a common occurrence with the IF diet, and this, adoptees claim, is why many people who start to eat this way will lose fat without changing what, or how much, they eat.
Dr. Monique Tello puts it nice and simple on the Harvard Health Blog:
“Between meals, as long as we don’t snack, our insulin levels will go down and our fat cells can then release their stored sugar, to be used as energy. We lose weight if we let our insulin levels go down. The entire idea of IF is to allow the insulin levels to go down far enough and for long enough that we burn off our fat.”
Hefty health Claims
The fasted state is a pretty fascinating one, and some research has found that it leads to a massive jump in Human Growth Hormone (HGH), which is linked to both fat loss and muscle gain, in clinical studies. Studies have also found that when you’re fasting, your cells start the cell-repair process, where old and dysfunctional proteins that build up inside cells are removed.
Even your genes are affected. Scientists have found that IF produces changes in the function of genes related to longevity and protection against disease, which might be helpful in the fight against cancer.
But putting the science aside for a second, there’s also the fact that – even though the IF diet allows you to eat whatever you want – limiting the window in which you eat often reduces calories automatically. For most people doing the 16:8 version, they’ll skip eating breakfast early in the morning, and not eat at night. So unhelpful Netflix-snacking is suddenly not an option.
There’s Always a Catch…
If it all sounds too good to be true, then you won’t be surprised to hear that there are detractors. For the most part, experts are saying that there are not enough human studies to completely endorse this regimen yet. Look for ‘intermittent Fasting’ on the European Society of Endocrinology, for example, and you’ll find that the top two articles are “Intermittent Fasting May Increase Diabetes Risk,” which talks about damage to the pancreas and an increase in abdominal fat tissue – and “Intermittent Fasting May Help Prevent Diabetes and Obesity”.
Makes you want to throw up your hands at science, right?
There is also some evidence that suggests that women don’t respond as well to fasting as men. One study showed that there was a decrease in how well women processed sugar (their glucose tolerance) while fasting. Other studies have shown that it’s just a tough regime for some people to adhere to (rebound overeating – it’s a thing.)
Yeah, it’s confusing out there.
So….what’s the conclusion?
Despite the reservations of doctors when it comes to wholeheartedly recommending this plan, a lot of the research coming out about intermittent fasting is promising, and for many people, the results speak for themselves.
Yup, it seems that fasting as a one-stop solution to weight loss may not live up to the hype, but, it can be a tool in your wellness toolbox, along with eating whole foods, regular exercise, and getting enough sleep.
If you try it, and it works for you, keep going. And let us know!