We’ve known for awhile that cocoa flavanols can help with both cognitive function and age-related memory loss, but new research now shows it can also help people with chronic kidney disease (CKD).

CKD, which affects more than 26 million people in the United States, is often caused by high blood pressure and diabetes. Once it develops, patients are at higher risk for kidney stones, kidney cancer, and cardiovascular disease — which is the number one cause of death for people with CKD. Knowing this, Dr. Tienush Rassaf, of the University Hospital Essen in Germany, and his team hypothesized blood vessel function could be improved in patients with CKD with the help of cocoa flavanols, antioxidants found in the cocoa bean plant.   

For their study, the researchers brought together 57 participants who were on dialysis, a procedure typically performed on patients who’ve lost 85 to 90 percent of kidney function, known as end-stage kidney failure. Then, they gave half the participants a beverage with 900 milligrams of cocoa flavanols every day for 30 days, while the other half drank a beverage with the same nutrients but without the cocoa flavanols.

After the 30 days, the researchers found the cocoa-flavanol drinkers had improved blood vessel function and decreased diastolic blood pressure. The participants who did not drink the cocoa-flavanol beverage, on the other hand, were found to have no observable effects on their blood vessel function or blood pressure. What’s more, this change appeared long before the 30 days were up — from the first drink, evidence of lower diastolic blood pressure and improved blood vessel function emerged.  

"Impressively, the degree of reversion of vessel dysfunction was comparable to the effects observed through administering statins or making dietary and lifestyle changes," Rassaf said in a press release. "Whether this approach also leads to a reduction in mortality is not clear and has to be investigated."

While these results are encouraging for those who currently live with CKD, it should be noted that eating chocolate won’t help  CKD, and it’ll surely be frowned upon by your doctor. Treatment for CKD usually comes down to controlling weight, eating as healthy as possible, and leading an active lifestyle. Before administration of cocoa flavanols can become a regular treatment option, however, the researchers said further study would be needed.

Source: Rassaf T, et al. Vasculoprotective Effects of Dietary Cocoa Flavanols in Patients on Hemodialysis: A Double–Blind, Randomized, Placebo–Controlled Trial. Clinical Journal of the American Society of Nephrology . 2015.