What if the fountain of youth were in your own kitchen? While we’ve come to expect certain physical and mental changes as an inevitable part of getting older, the fact is that the foods we eat—or don’t—may speed those processes along, aging us before our time. The reason is simple: “We eat too many processed foods,” says David Katz, MD, director of Yale University’s Prevention Research Center. “They’re often high in calories and low in nutrients such as vitamin B12 and omega-3s, so we end up with islands of deficiencies in a sea of excess.” These inadequacies can result in symptoms we tend to assume are due to aging, such as the four below. Work with your doctor to determine whether adjusting your diet or adding a supplement can help you look—and feel—younger.

Here are the mistakes: