- About 200 million people around the world are living with the vision loss condition age-related macular degeneration (AMD).
- Of the two types of AMD, most people have dry AMD.
- Past research shows there are several risk factors for AMD, including nonmodifiable factors such as genetics, and modifiable ones like eating a healthy diet.
- A new study has found that a combination of genetics and drinking instant coffee may increase a person’s risk of developing dry AMD.
Researchers estimate that about 200 million people around the world are living with age-related macular degeneration (AMD) — an eye condition impacting a person’s central vision, causing blurriness or other vision issues.
Of the two types of AMD, most people have dry AMD, where damage to the eye’s macula — an area located in the back of the retina — happens naturally with age. Wet AMD occurs when abnormal blood vessels grow in the back of the eye, harming the macula.
There are several
Specifically, following a healthy diet that is high in antioxidants like lutein and zeaxanthin, minerals like zinc, vitamins C and E, and omega-3 fatty acids could help lower the risk for AMD.
“AMD is a leading cause of vision loss among the elderly in developed countries,” Siwei Liu, MD, a researcher in the Department of Ophthalmology for Shiyan Taihe Hospital at Hubei University of Medicine in China, told Medical News Today.
“As there is currently no cure, identifying new modifiable factors is crucial for slowing disease progression, preserving vision, and improving patients’ quality of life,” Liu added.
Liu is the lead author of a new study published in the journal
For this study, researchers first obtained coffee consumption data for more than 500,000 participants from the UK Biobank genome-wide association studies (GWAS) summary statistics. Scientists broke participants into decaffeinated, ground, and instant coffee consumption groups.
Scientists also obtained both dry and wet AMD data for adults 50 and over from the Finngen GWAS dataset.
“Coffee is one of the most widely consumed beverages worldwide and is rich in polyphenols and antioxidants that may offer neuroprotective effects,” Liu explained.
“At the same time, growing evidence shows that genetics influence dietary preferences. Studying the genetic predisposition to coffee consumption and its relationship with AMD risk may help reveal potential causal links between diet and eye diseases,” the study author noted.
Researchers used the collected data and a variety of methods to determine their study’s findings, including mendelian randomization and linkage disequilibrium score regression (LDSC) to evaluate any genetic correlations.
At the study’s conclusion, researchers identified an overlap between a person’s genetic disposition towards drinking instant coffee and their risk for dry AMD.
Additionally, within this genetic correlation, scientists found that drinking instant coffee, compared to other types of coffee consumption, increased dry AMD risk by about sevenfold.
“This genetic overlap suggests that there may be shared biological pathways or metabolic mechanisms connecting the preference for instant coffee with the risk of developing dry AMD,” Liu said. “It provides new insight into AMD pathogenesis and offers a potential direction for personalized prevention strategies, such as gene-informed lifestyle interventions.”
Researchers stated they did not find any association between coffee consumption and wet AMD risk.
For the next steps in this research, Liu said she and her team plan to validate the association in independent populations and conduct functional studies to explore whether the metabolic pathways linked to instant coffee consumption are directly involved in AMD pathophysiology.
“We also aim to perform longitudinal cohort analyses to clarify the causal relationship between coffee intake and AMD progression,” Liu added.
MNT had the opportunity to speak with David I. Geffen, OD, FAAO, director of optometric and refractive services at the Gordon Schanzlin New Vision in La Jolla, CA, about this study.
“This study finds an interesting association with instant coffee and AMD,” Geffen, who was not involved in the research, commented. “With our population living longer, AMD is one of the leading disabilities in the senior population. Any change in lifestyle to minimize this risk is well worth exploring.”
“With the large increase in AMD seen in [the United States] it is important to continue with vital research in this area,” he added. “The costs associated with caring and treating AMD patients it is worthwhile to find ways to minimize the risk associated with this disease.”
Geffen said that while he found this research interesting, he would need to see a more direct association before he would tell patients not to drink instant coffee.
He explained that:
“Questions like how much instant were being consumed by those individuals with AMD. Also, is social economic class associated with this? Is there some lifestyle associated with the risk in these individuals? This is way too early to make large assumptions about instant coffee drinking.”
MNT also spoke with Benjamin Bert, MD, a board-certified ophthalmologist at MemorialCare Orange Coast Medical Center in Fountain Valley, CA, about this research, who shared that it fascinated him in two different ways.
“First the study demonstrates one of the future directions of medicine that we have been hearing about: directing care based off of someone’s specific DNA risk profile,” Bert, who was not involved in the research, explained. “In this study they found that people have a higher risk of dry AMD with certain genetic markers and consumption of instant coffee.”
“Which brings the second fascinating part of the study, food as medicine,” he continued.
“More and more we are realizing how our food and drink choices can impact our overall Health. This study once again points to the dangers of highly processed foods, like dehydrated instant coffee, compared to its more natural form of brewed coffee, which had no added risks.”
– Benjamin Bert, MD
“With additional research, it would be beneficial to know other foods that could be risks for these patients,” Bert added. “Is instant coffee the only food risk? Does the conclusion of this study apply to all highly processed foods?”
