By Kristen Mulvihill
Scheie Vision Summer 2020
A recent study led by Joshua Dunaief, MD, PhD found that a diet rich in dark green leafy vegetables is associated with decreased systemic C-reactive protein (CRP) levels over time. Subsequently, lower CRP levels are correlated with reduced risk of diseases promoted by chronic inflammation, including several eye diseases.
Chronic inflammation contributes to many diseases, including diabetes, rheumatoid arthritis, age-related macular degeneration, and several forms of cancer. Chronic inflammation can also lead to increased rates of cardiovascular events, such as strokes, heart attacks, and sudden cardiac deaths. CRP, a protein made in the liver, is a widely accepted measure of systemic inflammation, as CRP levels in the blood increase when a condition is causing inflammation in the body.
The study, published in the American Journal of Lifestyle Medicine, investigated whether patients advised to eat a specific diet rich in dark green leafy vegetables, which are high in beta-carotene, experienced reductions in high-sensitivity CRP (hsCRP) in the blood. The team, led by Dr. Dunaief, Adele Niessen Professor of Ophthalmology, and David M. Dunaief, MD, an internist, termed the diet the Low Inflammatory Foods Everyday (LIFE) diet, which includes spinach, kale, collard greens, Swiss chard, and bok choy.
In this retrospective chart review, the researchers, including Hannah Schultz, a fourth-year medical student at the Perelman School of Medicine, and Gui-shuang Ying, MD, PhD, Associate Professor of Ophthalmology, measured participants’ CRP levels at least twice over the course of a year. Adherence to the LIFE diet was assessed by measuring participants’ beta-carotene blood levels and by participant interviews.
Their findings suggest that adherence to the LIFE diet leads to increased beta-carotene levels in the blood and decreased CRP levels. Significantly, this type of diet may reduce the risk or severity of cardiovascular disease and other chronic diseases involving inflammation, ultimately improving quality of life for patients with these conditions.
“I was surprised by the magnitude of the LIFE diet’s effect. Those patients who adhered to the diet were able to lower their blood CRP levels from an average of about 7 to 1.75 within six months, which significantly lowers their risk for cardiovascular disease,” said Dr. Dunaief. “We think this would also lower their risk for complications of eye diseases that involve inflammation, including dry eye, glaucoma, age-related macular degeneration, diabetic retinopathy, and uveitis.”
Next, the team plans to study the effects of a key feature in the LIFE diet in a prospective trial for eye disease. In this new clinical trial, researchers will advise participants to incorporate a daily smoothie into their diet, similarly measuring adherence with beta carotene blood tests.
“We will likely start with patients who have wet age-related macular degeneration to determine whether this can decrease the frequency of their required injections,” explained Dr. Dunaief. Wet, or neovascular, age-related macular degeneration is typically treated with anti-vascular endothelial growth factor (VEGF) injections. Patients must receive these injections frequently—usually once a month—from an ophthalmologist, which can be burdensome to some.
The start date of this trial is yet to be determined, pending the COVID-19 pandemic.