Confused about feeling weak and Carbs

[JamesAA]

So I have these weak feeling/light headed sensations lately where I'm also mentally not as acute as normal.  On one hand I thought maybe my blood sugar has dropped (hypoglycemia).  So then I thought ok, well I'll cut back on the carbs and eat a higher protein diet.  But I exercise regularly.  It's not as intense as it used to be but I still bike at medium heart rates (aerobic zone) for 30-40 minutes in the gym--which isn't that hard, really.  Then I though, well maybe I feel weak because I'm not eating ENOUGH carbs.  Maybe it's not hypoglycemia and maybe me cutting back on carbs is a huge mistake.  I'm THOROUGHLY confused now.  Can anyone help??

Thanks,
James

[JamesAA]

Thank you Dr. Sharma for your response.  What could cause acute temporary shortage of blood or O2 to the brain?  And how would I know if I have anemia?  I've been under anxiety lately and have GAD (general anxiety disorder) with agoraphobia but the lightheaded spells always happen after I eat.   Also can high anxiety and near panic states cause one to feel faint and or nauseous (like throwing up)?  I got very anxious after my post meal lightheadedness came on today and within minutes I felt as if I didn't lay down right away that I was going to faint or throw up.  I averted either from happening and I didn't fully calm down til 30-45 minutes later--I partially dozed off to sleep after lying down when my initial panic symptoms subsides.  

[Arti Sharma, M.D.]

Hello and welcome!
Feeling light headed and weak can be due to several causes like acute temporary shortage of blood supply or oxygen to the brain,dehydration,low blood sugar, low blood pressure, panic attacks,anaemia.Serious conditions like heart attack, stroke and shock can also cause these feelings. Getting up suddenly from lying down position can also cause lightheadedness. In your case due to low carb diet your body is using other fuel sources, mainly fat, and it may take a few days for the new metabolic pathways to be effective. During this phase lightheadedness is possible. I will advise you to ensure that you are properly hydrated .Ensure adequate intake of electrolytes in fluids. If the symptoms still persist seek medical help. Hope you find it useful.
Good luck!