Many groups (e.g. for religious reasons) do fasting regularly, and have done it for millennia.
At worst, IF just limits your food intake, but it does not seem like it would provide you with an unbalanced diet.
As for my blood glucose levels, based on the continuous monitoring devices I've used, it's pretty stable. I may see a slight dip in the afternoon, then returns to baseline and stabilizes. After a meal, it will rise for about 30 minutes (within normal parameters), then back to baseline.
IF is anything but a fad diet and shouldn't be lumped in with such. If anything, one could argue that IF is one of (if not) the original eating patterns based on the lifestyles our hunter/gatherer ancestors and modern nomadic cultures. The modern concept of 3 squares a day might in fact be the fad.
Food has only been plentiful since the agriculture revolution about 12,000 years ago. Before then, it was feast and famine.
For anyone on the fence, I say give it a try (after consulting with your physician). The more studies we are seeing about this pattern, the more benefits we are discovering.
They're a bit pricey if you buy them direct (sans insurance). It feels like you have an additional sense when wearing it.
But "works for me" and "there are many studies that prove it's useful" is what everyone says about whatever diet they are currently doing.
I have seen the same (on this forum too!) for keto, paleo, vegetarian, piscitarian, vegan, carnivore, mediterranean. The "it's how our ancestors ate!" claim is also applied to all of the above.
Only time will tell which diet sticks, and which one was a fad.
Some studies suggest the benefits are significant, others suggest they’re neutral, but I’ve yet to find anything indicating that it’s innately risky to fast intermittently. Me not being aware of studies showing harm doesn’t mean it’s not possible, but it seems unlikely at this point. I’ve been doing it for the better part of 10 years or so and I always regret it when I stop. Fasting in general appears to be good for people when it’s controlled and done sensibly.
In the developed world it really does seem we do more harm to ourselves with what we do consume rather than what we don’t. Less is more (health) with common western diets.
You're pretty much correct:
The most relevant contraindication for any kind of fasting are eating disorders like anorexia. Also, don't try out fasting if you're taking metabolism related medication without consulting with your doctor.
A lot of research suggests that most lifestyle diseases that are prevalent in the developed world (like obesity, diabetes, heart attack, even some types of cancer and possibly also neurodegenerative diseases like Alzheimers) can be prevented and sometimes treated with a dietary intervention.
The optimal diet seems to be whole foods and mostly plant-based (though some people seem to thrive on meat) with occasional fasting periods.
It makes a lot of sense from an evolutionary perspective: Our ancestors didn't have all that sugary and industrially processed food and often spend extended periods fasting and searching/hunting for food. Processed foods highjack our preference for calorie rich, sweet and savory food but are often deficient in nutrients.