Yup I’ve had the hangover. Eating citrus right away helps. I now have a grapefruit the morning after. Also a date or 2 is a traditional way to break the Ramadan fast. My theory they both deliver sugar fast. Sparkling water helps too. You could also try the electrolyte tabs that runners and hikers use I did that once and it helped. I don’t have a hangover every time but it does happen. I think it’s worth it. Good luck.

Hi Tilly, it takes a while for your body to get used to fasting so these symptoms will gradually disappear.
Don’t under estimate the amount of water you need to drink on fast days, the more the better. I stop about three hours before bed to avoid too many night time loo visits, but I have a glass of water on the go all the time on a fast day.

I’m not sure that I agree with Slake about the need to deliver sugar quickly after a fast day as the last thing you need is for your blood glucose to soar as the subsequent drop will make you hungrier. I rarely eat before lunchtime on any day, and am not hungry the morning after fasting. If you need to eat IMO you would be better off having an egg based breakfast.
Having said that, we are all different and the beauty of 5:2 and the reason why it is so successful, is that we can adapt it to suit our individual needs and habits.

The most difficult day is the first fast and you’ve done that, good luck with the rest of your 5:2 journey.

Hi Tilly, agree with Amazon – effects in my experience are shortlived, you will soon get used to fasting if you persevere, and you need an unbelievable amount of water. Very strange but you will very quickly adapt and not feel at all weak and shaky. I must say though, your details indicate that you don’t need this for Wright loss so are doing it for health benefits and do appear to have undertaken a very long fast period -though, again agreeing with Amazon, making it fit to individual lifestyles is what makes this work. Good luck -you’ll love it, I’m sure!

Hi Ar-, re your problem with fasting, I have not had any problems myself but could I make some suggestions?. Read previous posters comments who have had similar problems to yours. Keep a daily food diary for a month and enter everything you eat, drink and do.
Look at the type of fish and the amount you eat on a fast day. Protein intake is important on any day but also on a fast day. Different fish contain different amounts of protein, eg Cod has less than a Tuna steak but Tuna has more calories per 100gm. Try other sources of protein such as chicken or a vegetable protein source such as quinoa. Look at the types of veg you have with your meal and maybe ring the changes, you may have an allergy you know nothing about. Record how much water you actually drink, it may be less than you think. Try different fast days and also look at the types of meals you have on a fast day. I have two meals, 1.00pm ish and 6.00pm ish. It works for me.
We are all different, do some research, ie Google sites such as Howmuchprotein.com or research sites with medical research on related subject matter. Remember you are not alone, others have similar issues such as yours but the main thing is experiment to find what suits you.
Good luck.