Coffee & eyes

Who would have thought that drinking a coffee a day can be good for our eyes as well as our mood!

The caffeine, a substance belonging to the methylxanthine class, is the most widely consumed central neurostimulant, with an average daily dose of between 100-400 mg, which we take in through the consumption of coffee, tea and caffeine-enriched drinks, to which we must add the caffeine contained in many metabolic energisers used by sportsmen and women or people with nutritional deficiencies.

Caffeine has anti-inflammatory and antioxidant properties, as reported in numerous studies on neurodegenerative diseases, such as Parkinson's and Alzheimer's disease.

Caffeine has also been shown to have beneficial effects in a number of systemic conditions, such as chronic stress, diabetes, attention deficits, and hyperactivity disorders. Its use is formally authorised for the treatment of apnoea in the prematurely born.

In the ocular field, caffeine can counteract the inflammatory processes that are triggered in the retina in progressive ophthalmic diseases such as macular degeneration. Retinal degenerations can become disabling, leading to low vision or blindness, as they are often characterised by ischaemic events and activation of inflammatory pathways in the cellular tissues involved in image processing and electrical signal transmission to the brain.

Caffeine, acting on specific receptors called adenosinehas been shown to counteract damage and preserve retinal cells.

This ability to protect the retina was the subject of a preclinical study carried out by the research team of the ocular pharmacology section of the University of Catania, led by Prof. Claudio Bucolo, "Caffeine Protects Against Retinal Inflammation"

This study is among the publications supporting the consumption of 'functional' foods and beverages, i.e. containing substances with therapeutic properties, which may act more or less positively, depending on one's lifestyle and the impact that foods or beverages have on each specific organism.

Overall, not many studies have specifically investigated the effects of caffeine on retinal diseases. Of particular note in this regard is the Coimbra Eye Study, a 2018 cross-sectional epidemiological study, which revealed an inverse correlation between caffeine consumption and AMD progression. The authors have, therefore, concluded that caffeine can be used as a nutritional supplement to slow down the progression of age-related macular degeneration, emphasising, however, the need for further investigation through additional preclinical pharmacological studies, such as the one just mentioned.

Good news, then, for all coffee lovers, who consider it a pleasure that would be very difficult to give up.

• Conti F, Lazzara F, Romano GL, et al. Caffeine Protects Against Retinal Inflammation. Front Pharmacol. 2022 Jan 6;12:824885. doi: 10.3389/fphar.2021.824885. PMID: 35069225; PMCID: PMC8773454.
• Yoon JJ, Danesh-Meyer HV. Caffeine and the eye. Surv Ophthalmol. 2019 May-Jun;64(3):334-344. doi: 10.1016/j.survophthal.2018.10.005. Epub 2018 Oct 24. PMID: 30365973.
• Raimundo M., Mira F., Cachulo M. d. L., Barreto P., Ribeiro L., Farinha C., et al. (2018). Adherence to a Mediterranean Diet, Lifestyle and Age-Related Macular Degeneration: the Coimbra Eye Study - Report 3. Acta Ophthalmol. 96, e926-e932. 10.1111/aos.