Instant Coffee Linked to Higher Risk of Blindness, New Study Finds
Instant coffee may significantly increase the risk of age-related macular degeneration (AMD) — one of the leading causes of blindness in the elderly. This conclusion was reached by scientists who conducted a large-scale genetic analysis using data from nearly 200,000 people. The study was published in Food Science & Nutrition.
Photo: commons.wikimedia.org by Julius Schorzman,
A small cup of coffee
Using Mendelian randomization and genetic correlation analysis, the researchers found that individuals with a heightened genetic sensitivity to instant coffee — meaning they are more likely to consume it in greater quantities — have nearly a sevenfold increased risk of developing AMD, a vision-threatening condition. In contrast, ground coffee and decaffeinated coffee showed no such effects.
The authors emphasize that the concern is not about regular coffee, but specifically instant coffee — its production involves the formation of substances that can trigger inflammation and oxidative stress in the retina. The role of so-called advanced glycation end-products (AGEs), which form during the high-temperature drying of coffee extract, is also under discussion.
While a direct causal relationship has not yet been definitively established, the study suggests that physicians should consider genetic risk when making dietary recommendations and particularly advise limiting instant coffee intake for individuals predisposed to AMD.
Earlier research highlighted the benefits of black coffee. It showed that drinking 1-2 cups per day may reduce the risk of premature death by 14 percent — especially when consumed without sugar or fatty additives.
