Ijmworks, have you checked your BP when you feel lightheaded? Usually lightheadedness indicates low blood pressure. I take BP medication which I’ve reduced twice since starting the 5:2 on May 10. I’m down to half a pill in the morning. But on FD or when I haven’t eaten my first meal of the day, the BP med kicks in and my BP numbers are both well under 100 and my pulse increases, trying to keep the blood pumping. I’ve found that a little salt in a glass of water, plus just drinking a couple glasses of water gets it back up within half an hour. A cup of miso soup which is very salty works too. Caffeine will raise it temporarily. My normal BP now, with the meds is usually under 140/90. I’m going to make an appt with my doctor to discuss next week.

If you’re feeling lightheaded for longer than just a few seconds when standing up quickly and your BP is high, you should probably see a doctor. Keep in mind that your BP can change often throughout the day. And BP meds, especially those with diuretic in them can make it too low if you haven’t eaten anything in a while. It’s good to check it when you feel “different”. I can usually tell when mine is really high (hasn’t happened since starting the 5:2) and definitely know the feeling of it being very low.

Let us know what happens and good luck with the 5:2.