Obesity is a known risk factor for many chronic health conditions including diabetes, diseases of the heart and blood vessels, and cancer. Obesity may also contribute to the development of age-related macular degeneration (AMD), according to some preliminary studies. Doctors consider a patient obese if their body mass index (BMI) – a calculation comparing body weight to height – is 30 or higher.
Obesity can trigger an inflammatory response in the immune system that leads to rogue cells traveling throughout the body, where they may cause unexpected changes in places like the eye. These changes may eventually develop into AMD.
A recent study of obese mice published in Science provides some data to support the AMD-obesity link. Even after mice had slimmed down from gorging on a high-fat diet, researchers found that they were more likely to get AMD-like lesions in their eyes.
It’s difficult to generalize these results for human bodies, however, as there isn’t an ideal animal model for macular degeneration, says Christina Weng, MD, MBA, FASRS, a retinal specialist, surgeon, and professor at the Baylor College of Medicine. Researchers must rely on artificially induced settings that may not happen in real life.
Also, it can be difficult to isolate obesity alone as a risk factor that is a known contributor to AMD, says Weng, as obesity tends to be present along with other health issues like heart disease, high blood pressure, and poor diet. Using a more holistic approach, she endorses lifestyle habits known to promote wellness to her patients in the hope of warding off all manner of chronic illness.
“I recommend all patients follow a healthy diet,” she said. “There is some research that suggests that the Mediterranean diet specifically reduces the risk of AMD, but I don’t push that as much as an overall healthy diet.”
Since several of the main risk factors for AMD, such as age and genetics, are beyond individual control, it’s critical to try to maintain optimal health by focusing on what can be changed, like developing a regular exercise routine and a nutritious diet.
“What we tell patients is the most well-established modifiable risk factor is smoking. The other ones, such as obesity and other lifestyle things, they’re not as strongly associated,” said Vaidehi Dedania, MD, a retinal ophthalmologist and surgeon at NYU Langone Health. “Although, because they’re modifiable, we still recommend patients improve their lifestyle and decrease their level of obesity.”
