It has been said many times, you are what you eat. What we eat has a direct effect on our bodies, not just in terms of our weight and cardiovascular health, also in terms of vision. Two studies have shown that caffeine and carbohydrates are linked to the development of glaucoma.
A study done at the Icahn School of Medicine at Mount Sinai showed that those who consume large amounts of caffeine each day (480 milligrams or about four cups of coffee) may increase the risk of glaucoma for those with a genetic predisposition to the disease.
Researchers used UK Biobank, a biomedical database supported by various health and government agencies, for this study. They looked at the records of more 120,000 people between the ages of 39 to 73 years old who provided DNA samples and responded to questionnaires about how many caffeinated beverages they drink a day and how much food containing caffeine they eat a day, including information about types and size. They also answered questions about glaucoma, specifically if they had glaucoma or had a family history of glaucoma. After three years, they had their intra-ocular pressure checked and eyes measurements done.
Researchers looked at the relationship between caffeine, intra-ocular pressure and self-reported glaucoma. Then they studied if accounting for genetic data modified these relationships. They found that high caffeine intake in and of itself wasn’t associated with increased intra-ocular pressure or glaucoma. The trouble comes with people who have a genetic predisposition to elevated intra-ocular pressure. Those in that category who consumed more than 480 milligrams or four cups of coffee a day had a 0.35mmHg higher intra-ocular pressure. Also, those with the genetic predisposition to elevated intra-ocular pressure had trouble if they consumed more than 321 milligrams of caffeine a day, which is three cups of coffee. They had an almost 4 times higher prevalence of developing glaucoma when compared to those who drink no to very little caffeine and were in the lowest genetic risk group.
It isn’t just beverages with caffeine that those who are at risk for developing glaucoma need to watch out for, carbs can be a problem, too. A study published in the European Journal of Ophthalmology has shown an link between a diet high in carbohydrates and glaucoma.
This study looked at over 18,000 participants who were followed over 10 years. The participants’ carbohydrate intake was collected at the start of the study and divided into nine different carb food sources. Self-reports of a glaucoma diagnosis and diabetes status were also collected at the start of the study.
During a 10-year period, 242 cases of glaucoma were identified among the participants, even when those who had diabetes was excluded, scientists found that those with the highest carb intake had a 77 percent risk of developing glaucoma compared with those who had the lowest carb intake. The most interesting thing was that none of the nine carb food groups were individually related to glaucoma. So, it is really a case of the total amounts of carbohydrates, as opposed to the specific type of carbohydrate that plays a role in the development of glaucoma.
Before you toss out your Starbucks coffee and bagel, know that the research for both studies is ongoing and in all things moderation.