I've not really got a chance to read QS's article so will get back to it later. I know there are some theories about IF not being as effective for women - Mark's Daily Apple has a fair bit on this. I agree however that it doesn't say it's 'really bad for women' - just to read the research, be aware of effects and act accordingly. More studies are always needed!
However... I've not found any ill-effects from IF. I'm certainly not experiencing anxiety, insomnia or a disrupted cycle. My previously acne-prone skin is clear as a bell. But then again, I'm not following a set IF plan, which may be a contributing factor.
My way of 'fasting' is simply that I only eat when I'm hungry. It's not a regulated thing, I don't really choose fasting days and I don't starve myself or stretch the fast beyond what I'm comfortable with. When I'm properly fat-adapted (i.e., in ketosis), I find it very easy to go around 16 or more hours without food. I listen to my body - I know what my hunger cues are. If I'm hungry, I eat - if I'm not, I don't. Some days I'm hungrier than others!
I definitely don't count calories - I loathe the whole calorie-counting palaver as I don't believe all calories are created equal and I also think it can lead to some very dodgy eating habits ('I've got 200 calories left over today so I'll have a Mars Bar and then wonder why I'm not losing weight' etc). I find the 5:2 thing interesting from a health POV but it's too regulated for me.
For me IF is fine, but Your Mileage May Vary
. I don't find it problematic but I'm pretty well fat-adapted so it's easy. I make sure I eat plenty of fat when I do eat, and drink as much water as possible when fasting. I'm now sitting at a very happy 10stone (in fact am just under this morning!) down from almost 12st. It's low-carb that's really done it for me, IF is really just an added aspect.