The relationship between calcium and AMD has been a subject of scientific debate for years. A major study from the National Eye Institute now offers reassuring news: eating a calcium rich diet or taking calcium supplements does not appear to increase the risk of age related macular degeneration. For the millions of older adults who rely on calcium to protect their bones, the findings offer meaningful clarity.
What the Research Reveals About Calcium and AMD
The study, led by Emily Chew, M.D., director of the Division of Epidemiology and Clinical Applications at NEI, analyzed data from 4,751 participants in the Age Related Eye Disease Study, a landmark multicenter trial that tracked a range of nutrients and their effects on AMD onset and progression over an average of 10 years. Participants ranged from those with no AMD at baseline to those with intermediate or late stage AMD in one eye.
The results, published in JAMA Ophthalmology, directly contradict an earlier study that linked high calcium levels to greater AMD prevalence. Instead, this analysis found the opposite pattern: participants with the highest calcium intake, whether from food or supplements, had a lower risk of developing late stage AMD compared to those in the lowest intake groups.
Calcium Supplements and Eye Health
Approximately 50 percent of men and 65 percent of women in the United States regularly use calcium supplements, primarily to build bone density and prevent osteoporosis. Recommended daily intake is 1,000 mg for adults aged 50 and under and 1,200 mg for those over 50. The concern that these supplements might simultaneously harm vision had understandably worried both patients and clinicians.
According to Chew, the latest findings provide no evidence that calcium intake needs to be modified for individuals already taking it for other medical reasons. In other words, patients should not discontinue or reduce calcium supplementation out of fear of AMD risk based on current data.
Why the Connection Between Calcium and AMD Remains Complex
Despite the encouraging direction of the findings, researchers urge caution. Chew noted that the apparent protective association between calcium and AMD could be influenced by confounding factors. People who are diligent about calcium intake may also tend to follow healthier diets overall, exercise regularly, and adhere to prescribed medications, all behaviors that independently reduce AMD risk. The study design was retrospective, meaning it looked back at previously collected data rather than prospectively tracking participants under controlled conditions.
This distinction matters. A retrospective analysis can identify associations but cannot definitively establish that calcium itself is responsible for reduced AMD risk.
The study also highlights how the connection between calcium and AMD intersects with broader patterns of aging. As the population over 65 continues to grow in the United States, understanding which nutritional habits protect long term vision health becomes increasingly urgent. Calcium remains one of the most widely consumed supplements in the country, and clarifying its role in AMD prevention is a public health priority that warrants continued investment in well designed prospective trials.
The Path Ahead for AMD Research
The NEI researchers emphasized that prospective studies are needed to resolve whether calcium plays a genuinely protective role against AMD, and whether intake levels specifically affect drusen formation or the development of AMD subtypes. Drusen are deposits that accumulate in the retina and are a hallmark of intermediate AMD progression.
For now, the study adds to a growing body of evidence suggesting that nutritional factors, including calcium and AMD risk, are deeply interconnected with aging eye health. The research was supported by intramural program funds from the NEI and contracts from the Age Related Eye Disease Study program.
FOMAT conducts clinical research across multiple therapeutic areas, including ophthalmology. To explore active studies, visit FOMAT’s patient studies page.
For the full source, see the original release at NIH.gov.