Dr Lisa Zhuoting Zhu and researchers at CERA’s Ophthalmic Epidemiology have discovered a correlation between tea and coffee consumption and the thickness of the macular retinal nerve fibre layer. The macula, responsible for central vision and the retinal nerve fibre layer, transmits visual information to the brain and shows increased thickness with a daily intake of two to three cups of coffee or at least four cups of tea.
Drinking coffee or tea could have an effect on the brain
According to Zhu, the thickness of the macular retinal nerve fibre layer can be instrumental in measuring brain health. Thinner layers were associated with a higher risk of neurodegeneration. The frequency of coffee and tea consumption across different cultures raises the need to understand the health effects. Researchers surveyed over 35,000 individuals in the UK Biobank study using a touchscreen questionnaire to determine their average daily intake of coffee and tea over the past year.
The frequency of coffee and tea consumption across different cultures raises the need to understand the health effects involved. Researchers surveyed over 35,000 individuals in the UK Biobank study using a touchscreen questionnaire to determine their average daily intake of coffee and tea over the past year.
People who drink coffee have thick macula retinal nerve fibre
The study divided participants into four groups based on their daily coffee consumption: zero cups, up to four cups, and more than four cups per day. Using optical coherence tomography (OCT) scans, researchers measured the thickness of the macular retinal nerve fibre layer. The scan results indicated a noteworthy thickening of this layer among coffee drinkers, particularly those who consumed two to three cups daily.
According to the study, tea drinkers who consumed over four cups daily experienced a significant increase in macular thickness. Similarly, researchers found an optimal amount of coffee consumption for maintaining a healthy macular retinal nerve fibre layer thickness, referred to as a “sweet spot.” However, the study emphasizes that not all coffees are equal, as instant coffee may be associated with negative health outcomes.
