Question

when i get up from reading a book or doing something that includes little movement i start to see black and start to get disoriented for around 5 to 10 seconds why is that???

Answer 1

That may be dehydration be careful

Answer 2

Answer:

Occasional dizziness or lightheadedness may be fairly minor — triggered by mild dehydration, low blood sugar or overheating. Dizziness or lightheadedness may also happen when you stand after sitting for a long time. If these symptoms happen only occasionally, there's likely no cause for concern.

Explanation:

Mayoclinic.org