You may have heard of the alkaline diet thanks to its celebrity following—including fashion designer and former Spice Girl Victoria Beckham, who Tweeted that she loves the book “Honestly Healthy: Eat With Your Body in Mind, the Alkaline Way.” But what exactly is it?The alkaline diet, which involves eating more alkaline foods—such as fruits and vegetables, with kale and raisins being particular alkaline powerhouses—and reducing your intake of high-acid foods—such as dairy, meat, wheat, fish and carbonated drinks, including soft drinks—claims to help followers reduce inflammation, lower the risk of diabetes, and lose weight. But what’s acid and what’s alkaline isn’t always so obvious. Many vegetables and fruits are more alkaline—including certain foods you might think of as acidic, such as lemons and other citrus, which actually don’t produce acid during digestion.So is there any proof that gearing your diet towards alkaline-based foods is beneficial to your health? Previous research showed mixed results, but a November 2013 study in the journal Diabetologia, followed more than 66,000 women—all teachers in France—over 14 years to see if there was a specific link between what the women ate and their risk of type 2 diabetes. In particular, the researchers wanted to know whether eating foods high in acidity raised the women’s diabetes risk, and if eating a more alkaline diet helped protect them against diabetes, one of the biggest killers.For the first time, the research linked a high-acid diet with an increased risk of developing type 2 diabetes. Even more worrisome, the risk tended to be higher among normal-weight women compared to overweight women.The question of high-acid versus alkaline foods relates to how the body—and the kidneys, in particular—processes what we eat and drink. “As part of the food breakdown process, some acid is produced; this can be gotten rid of by the body in two ways: breathing out and through the kidneys,” explains Deidra C. Crews, M.D., an assistant professor of medicine in the division of nephrology at Johns Hopkins University School of Medicine in Baltimore. “Certain foods lead to a greater amount of acid that needs to be gotten rid of. Generally these are animal-based foods, and more plant-based foods have lower acid content.”When you eat acid-forming foods, try balancing them out by loading up on more alkaline foods. For instance, a kale salad with fish.