This is so true!
Biochemical stressors such as sugar, certain foods (wheat, dairy, corn, soy), chemicals/additives/preseratives, environmental toxins, and more can cause or contribute to your symptoms. Whether it's back pain, neck pain, headaches, fatigue, etc. there is almost always a biochemical factor.
You may notice your symptoms or pain increase or flare up on days that you eat more bread, sweets, dairy, corn, or soy, or other food stressors. You may notice that it seems your adjustment didn't "hold" for very long. This can oftentimes be due to a chemical stressor that knocks a vertebrae right back out.
We can use muscle testing in the office here to determine which foods and other chemicals/toxins are affecting and stressing your body the most. Then it's up to you to eliminate those dietary stressors!
Start taking note of what flares up your symptoms, and start cutting down on the problematic foods!