chloehlambert – I’d love to help you but I haven’t really had any bad side effects either. I had one MAJOR headache (probably a migrain – dunno, never had one before) about 6 weeks in but that was probably just a combination of dehydration from not drinking enough water that day and my hopelessly non-human-friendly work environment. I went home, collapsed fully clothed into bed, had a little sleep and continued with the fastday when I woke up.

I also had a reaction to doing a big swim on a fastday early on. I’d had my 500 calorie meal but was so starving when I got back from the pool that I just HAD to have a small slice of cheese or my stomach felt like it would implode. I think that was just getting used to functioning normally on restricted calorie days though. I now swim the same distance on absolutely no calorie intake whatsoever every Monday and have my 500 calories after the swim. No problems.

All of the other side-effects I’ve had have been completely positive ones.

I noticed that i used to wake up at 4am after every fast day – this lasted for about 4 months. But now i’m 9 months in and that’s stopped! other than that no side effects (e.g. my periods have stayed completely regular throughout) and i feel great!

I think one of the thing most 5:2ers like is that the whole thing is solidly evidence based.

Rather than picking out a few stories that support your theory, how about doing some research?

Yes ive got some side effects. I keep walking along the street and men walking past me keep crashing into lamp posts as they eye up my new slim finger.
The other main side effect is on my purse. I’m having to spend money on a brand new wardrobe.
Other than that nothing really.

Haha meant to say figure. Not finger! That would be a very strange side effect.

Chloe – if you are reading these responses, I really don’t know if there is such a story – I am 63, was 90.8kg, 7.2 cholesterol and 3.2 tryglicerides in late January, 12 weeks later (still 63) 81.5kg, 5.9 cholesterol and 0.8 tryglicerides.
Now 74.7kg (LOSS OF 16.1kg). I have had NO SIDE EFFECTS, I fast on water only twice a week from after dinner day 1 to lunch day 3 (40 hours) and either swim 3km or crosstrain 1 hour 5 days a week. I feel fantastic, more energy than I have had for years and less aches and pains. No problems with sleep, headaches, anything. I think you need to understand that this is not a “diet” it really is a way of life which we can adopt for life! On my fast days I cook dinner for my husband – he sits and eats and has his wine and I drink water – no problem. I wiwll talk to you if you want but I can’t see the basis for your story. Best wishes, Vicki

Hi there,

I agree with all of the above its funny how the media is trying to find negatives on this, I did a lot of research before starting this way of life and I could not find any negative sites to do with fasting, since fasting I feel great, its amazing, less bloated, I feel lighter even though not much weight has been lost and have decreased appetite.

I think a story of the positives would be great

I’ve just completed my very first fast day… By the 20hour mark I developed a terrible head ache (probably from lack of water) and I felt extremely dizzy. Otherwise I’m rather surprised how easy it was to make 25 hours… Ill try for longer on my next fast day : )

A coffee detox will definitely give you a headache, but more likely you are not getting enough salt. Drink some broth (I use stock cubes or bouillon powder if I haven’t made broth) or hot bovril.

Contrary to popular myth, you do need salt, and it will do you no harm and much good.

Lmao @laure throwing shade 😉

I’m loving this thread.

I’ m having trouble not buying the whole of H&M now that I’ve gone from a UK size 18 to a 10/12 and fit into S-sized skirts.