The continuing thread for those of us following either the 5:2 diet or the alternate-day fasting diet. Both are two versions of Intermittent Fasting, which you can read more about here.
The 5:2 diet was featured on Horizon in August 2012, and essentially requires you to fast for 2 non-consecutive days per week. The other 5 days, you can eat what you like. Alternate-day fasting is just how it sounds; you fast every other day. By "fasting", we mean that we keep our calorie consumption very low, around 500 calories on average, on those days.
I know a number of people lurk on this thread, as this is currently quite popular. Please just jump in and post if you're new- we won't bite. Well, maybe on a fast day. 
You'll find a lot of support here.
Here is a list of links to get you started with this way of eating. Please let us know if you find a new article or some other information online:
First things first, here are links to some of our previous threads: most recent one before that another one etc!
Another thread which breadandwine has started is a good resource for some of the links and tips that get lost in these big threads. In addition to sharing links, we try to condense some of our top tips for fasting there. Keep in mind, we all do this differently, so these are just tips, not rules.
frenchfancy has a recipe thread over here, please post any low-calorie recipes there so they don't get lost in these bigger threads!
Here is the link to the BBC article regarding Michael Mosley's findings, which was featured on Horizon.
Here is where I would link to the aforementioned Horizon programme, but it appears as if the BBC have finally noticed it on YouTube and have taken it down. Here is a link to the programme's page on iPlayer, which features a couple of clips, and might have updates eventually. Let us know if you find another site hosting it.
A blog post here gives some of the scientific explanation for why this way of eating helps you to not only lose weight, but improve your all-around health.
A Telegraph article which comments on the diet and gives a brief overview.
A study discussed here gives commentary specifically addressing the effect of this diet on obese people (both men and women), with regard to both health and weight loss. ("After 8 weeks of treatment, participants had an average 12.5 lbs reduction in body weight and a 4 cm decrease in waist circumference. Total fat mass declined by about 12 lbs while lean body mass remained relatively constant.) it also mentions "Plasma adiponectin, a protein hormone that is elevated in obesity and associated with heart disease, dropped by 30%. As did LDL cholesterol (25%) and triglycerides (32%).")
Important link if you are currently your ideal BMI: this appears to suggest the benefits for women at a lower BMI might not be seeing the same health benefits that are found on men at their ideal BMI.
And for those already fasting, here is a link to 100 snacks under 100 calories. We tend to favour lots of hot drinks during the day (count your milk if you use it!)
Another food link, here is a link to the BBC Good Food site, with a list of low-calorie soups.
We mentioned BMR and TDEE often. Total Daily Energy Expenditure (TDEE) quantifies the number of calories you burn in a day. This measure is best estimated by scaling your Basal Metabolic Rate to your level of activity. TDEE is critical in tailoring your nutrition plan to desired fitness goals. Here is a link to a calculator to help you figure out how many calories you should be eating in a day. (This is a new calculator to previous threads, this one seems to give me approximately the same results the last one did, but without the virus warnings on my browser!)
A BIG THANK YOU to all who have been contributing, btw. Most of us are learning this way of eating as we go along. All of the links above have been posted by others in our previous threads, and they've been very helpful. Sorry if I haven't given credit where it's due, but it was just enough of a job getting all the links re-copied and back into one post.
Come join us, and tell us about your experiences with this diet!