or, if you have resources and don't feel like eliminating foods to find out, you could always go in for food allergy testing. another option is to try eating probiotics to get your intestines well-populated for more efficient digestion.
i notice a huge difference in how my body functions (including my brain) according to what i eat, especially as i get older.
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161 Aspie / 51 NT - Aspie Quiz (very likely an aspie)
36 - AS Quotient
115 aloof, 123 rigid, 89 prag - Aut/BAP
24 - HSP / ADD Quiz- 41, Inattention: 24, Hyperactive/Impulsive: 17
"Odd and different is beautiful" -- Tyra Banks