I tried intermittent fasting for two weeks, and here’s what happened
Intermittent fasting scores a lot of great press (including here on Coach), because it’s more than just a fad diet: a new study indicates it speeds up metabolism, burns more fat, and therefore leads to weight loss.
In case you’re not up to speed with intermittent fasting (IF) yet, it refers to any food schedule where you eat normally for a certain period of time, then cut back for a subsequent period of time, then repeat the cycle.
Popular IF intervals include the 5:2 diet, where you eat normally for five days then cut calories on two non-consecutive days; 16:8, where you only eat within an eight-hour window (say, between 11am and 7pm); and 12-hour overnight fasts.
Some intervals are even longer: Recent Australian research suggested a two-weeks-on, two-weeks-off IF cycle helped study participants lose weight and keep it off more than traditional dieting.
A study published in journal Cell Research tested IF on mice, finding that rodents who fasted for 16 weeks weighed less than those who didn’t fast, even though both groups ate the same amount of overall calories.
The fasting rodents also had more stable glucose and insulin systems — signs that their bodies were operating better. (In humans, elevated blood glucose and insulin resistance are linked to higher odds of being overweight and obese, and of cardiovascular disease.)
A follow-up experiment showed IF mice made these gains in only six weeks.
The Canada-based research team found that, basically, IF activates metabolic pathways that trigger fat cells to burn stored fats or lipids by generating heat.
“Intermittent fasting without a reduction in calorie intake can be a preventative and therapeutic approach against obesity and metabolic disorders,” proposed Dr Kyoung-Han Kim, the study’s lead author from the University of Ottowa, in a statement.
The catch is that the mice were put on an extreme IF regimen of two days of normal eating followed by one day of no food at all — which wouldn’t be practical (nor advisable) for any of us humans to do.
The good news is that you don’t need to opt for zero-food fast days to gain the weight-loss and other health benefits. There isn’t one method of IF that will work for everyone — so it’s worth experimenting to find one that you can stick to.
“There’s not one diet [that] fits all,” she said. “I know a lot of people have told me they find it much much easier to do [IF] than follow a particular diet,” said nutrition expert Dr Joanna McMillan, as Coach reported last week.
“The best long-term studies we’ve got are showing that fasting is at least as effective as more conventional dieting techniques, when it comes to weight control.”