New research from Arizona State University suggests that the biological foundations for brain health may be established far earlier in life than previously thought, according to the study. The study compared blood samples from 30 adults in their 20s and 30s, half with obesity and half at a healthy weight, to those with obesity who had significantly elevated levels of NfL, a biomarker often identified as an early warning sign of neurodegeneration. The researchers also found that obese individuals with obesity showed high levels of inflammation-driving proteins and enzymes, indicating liver stress, which correlated with lower choline levels. This suggests that some biological pathways leading to Alzheimer's may become active decades before symptoms emerge, particularly in people with obesity or metabolic dysfunction. Choline is essential for making acetylcholine, a neurotransmitter that supports memory and learning, yet up to 90% of Americans fall short of recommended choline intake.