New Study Reveals Blood Proteins That Predict Disease-Causing Aging Cells - Video

A simple blood test may one day reveal which parts of the body are aging faster than others-and even predict a person's risk of developing diseases such as Alzheimer's, ALS, or lung cancer years before symptoms appear, according to a new study published in Nature Medicine.

Researchers analyzed more than 7,000 plasma proteins from 60,542 people and used artificial intelligence to estimate the biological age of over 40 different cell types, including brain, immune, muscle, endocrine, and respiratory cells. They found that accelerated aging in specific cell types was strongly linked to a higher risk of age-related diseases, while younger-looking cells were associated with better long-term survival.

One of the most striking findings involved Alzheimer's disease. People carrying the high-risk APOE4 gene variant had biologically older astrocytes, brain cells that support neurons. Among participants with two copies of the APOE4 gene, those with extremely aged astrocytes were three times more likely to develop Alzheimer's disease than those with younger astrocytes. Faster aging of other brain cell types was also associated with greater cognitive decline and dementia severity.

The researchers also found that cellular aging was linked to diseases beyond the brain. Individuals with biologically older skeletal muscle cells were 12.7 times more likely to develop amyotrophic lateral sclerosis (ALS). Among current smokers, accelerated aging of lung cells increased the risk of lung cancer by 58% compared with smoking alone.

Cellular aging also appeared to influence overall survival. Participants with mostly normal cellular aging had an approximately 90% survival rate over 15 years, while those with more than 20 extremely aged cell types had survival rates of only about 34%. In contrast, younger immune and nerve cells were associated with better survival outcomes.

The researchers say blood-based protein profiling could eventually help identify people at high risk for age-related diseases before symptoms develop, allowing earlier monitoring and more personalized prevention strategies.

REFERENCE: Ding, D.Y., Bot, V.A., Chen, K.L. et al. (2026). Plasma proteomic signatures of cellular aging predict human disease. Nature Medicine. DOI: 10.1038/s41591-026-04446-y, https://www.nature.com/articles/s41591-026-04446-y