Early metabolic disruptions and choline deficiency were associated with a number of negative health effects, including higher inflammation, signs of liver strain, and higher levels of markers of brain damage in a recent observational study of younger adults with obesity conducted by researchers at Arizona State University. The findings were published in Aging and Disease.

The small but measurable shifts resembled patterns seen in older adults with cognitive impairment, according to the study authors.

While obesity is long known to increase the risk of chronic conditions, this study is unique in highlighting that its influence on the brain may develop much earlier into adulthood, in tandem with insufficient choline intake.

The study involved 30 adults in their 20s and 30s, split evenly between those with obesity and those of healthy weight. Each participant provided a fasting blood sample, which was analyzed for circulating choline, inflammatory cytokines, insulin, glucose, liver enzymes, other metabolic measures, and NfL.

While no behavioral differences were observed, as was expected, there were higher levels of neurofilament light chain (NfL), a protein that is released when neurons are damaged. NfL was linked to low blood choline levels in these young adults, and is often found at elevated levels in people with mild cognitive impairment and Alzheimer’s disease. Observing these markers in young adults suggests that obesity can create markers of risk in the brain well before symptoms appear.

Choline status served as a central aspect of the study because it is implicated in cell-membrane structure, inflammatory status, liver function, and the production of acetylcholine, a neurotransmitter important for memory. Obese participants with substantially lower levels of circulating choline saw stronger signs of inflammation, insulin resistance, liver enzyme elevation, and NfL.

Researchers also observed that women had lower choline levels than men, which coincides with the fact that women experience higher rates of cognitive aging and Alzheimer’s disease.

Between both groups, there was a consistent pattern. Young adults with obesity were more likely to have low choline levels, greater inflammation, metabolic stress, and signs of neuronal damage. While the study is observational in nature and doesn’t reveal causation, the authors noted that the biomarkers found in young adults with obesity and low choline status resembled those observed in older adults with cognitive impairment.