I had a few problems and my husband had lots of problems being light headed during the first 6 months of going paleo this time. I asked around and others have had the problem too. One doc (integrative medicine and MD) suggested it was due to low adrenal function and or thyroid issues. We were on thyroid supplements already so I focussed on meditation to try to improve things. It helped a little. My husband isn't complaining of being dizzy when he sits up in the morning any more so its likely to have reduced in severity or I'd have continued to hear about it.