Recently, I have been getting a ‘black dot’ in my vision intermittently, say like 5-10 times in a day.  For the past 1 week, I have been working continuously on my PC, with very little rest and sleep.  I am also trying to shed off the 1kg I had gained as a result of binging on durians for the past 1 month!!  So today I decided to google search this problem and this is what I have found from http://www.steadyhealth.com/anorexia_black_dots_and_bright_flashes_in_vision_t216719.html on one of the questions submitted by the forum user:

Question from a forum user:
Hi I am 39 and have suffered with anorexia for most of my life. I recently come out of treatment but am struggling to maintain I have started to restrict again and I have noticed that I am getting alot of black dots in my vision for no apparent reason and I have also started to experiance bright flashes that look abit like loads of tiny stars. I eas just wondering if this is due to lack of nutrients in my diet and also should I be concerned or is it just an harmless side effect.

Answer from the moderator:
That is not a harmless side effect. People can get this when they have eye disease, a lack of or sudden overabundance of oxygen to the brain, or high or low blood pressure. All of these could be side effects of anorexia. When you don’t eat enough protein and/or vitamin A, this could cause eye disease. When you don’t drink enough, or drink without enough food, this could affect your blood oxygen levels. When you don’t eat enough, your blood pressure could get dangerously low.

My blood pressure has always been low. I also tend to be light headed, feel dizzy and see darkness if I get up suddenly from a squatting / sitting position on the floor. My eye sight is also not perfect as I have short sightedness, long sightedness and slight astigmatism. I have NOT been wearing my glasses for over 10 years now! Maybe I should get my eyes checked by the optometrist / optician if the black dot in vision continues.

Has anyone experienced this before?