New research from China suggests instant coffee consumption may significantly increase the risk of developing dry age-related macular degeneration (AMD), with researchers recommending people at high risk for AMD should avoid instant coffee altogether.

The study, led by Dr Qi Jia from Shiyan Taihe Hospital, Hubei University of Medicine, used genome-wide association studies and advanced genetic analysis techniques to examine the relationship between coffee consumption and AMD development.1

“Our results revealed a genetic correlation between instant coffee consumption and dry AMD, with each standard deviation increase in instant coffee intake associated with a corresponding odds ratio of approximately 6.92 for dry AMD, indicating a 6.92-fold increased risk,” Dr Jia and colleagues reported.

The study employed multiple analytical methods including linkage disequilibrium score regression, Mendelian randomisation, and colocalisation analysis to provide comprehensive evidence.

The researchers found that although overall coffee consumption showed no causal relationship with AMD, instant coffee specifically demonstrated a significant link. The heightened risk of instant coffee may relate to its manufacturing process, which involves intense heat treatment and concentration. This process generates high levels of byproducts that are linked to oxidative stress and inflammatory responses in retinal cells.

The findings contrast with some previous studies suggesting coffee may reduce AMD risk and slow progression. However, the researchers noted their detailed stratification of coffee types yielded different results, indicating potential biases in earlier research.

Reference available at mivision.com.au.