Plant-based diets remain trendy as ever these days, and many vegetarians, or those simply trying to eat less meat, are seeking alternatives to animal products as a way to maintain a healthy weight and heart. And they're not without reason: Compared to meat eaters, vegetarians tend to have lower cholesterol levels and blood pressure, which is linked to a reduced risk for heart disease and certain types of cancer, says Harvard Health.

If you're not careful, though, an unbalanced vegetarian diet can cause deficiencies in important nutrients like B12, a vitamin that's not only essential for healthy brain function but also increasingly difficult for our bodies to absorb as we get older. There are also certain drugs that cause increase your risk for B12 deficiency, along with having weight loss surgery or a digestive disorder. When you're deficient in B12, you may feel fatigue, nausea, muscle weakness, and tingling in the hands and feet. You may also feel forgetful and anxious, your skin may become more pale, and your vision can decline. See your doctor and get a blood test done if you suspect you're lacking this important vitamin, and then overhaul your diet to get more of it. Vitamin B12 also helps you immune system stay strong, and it's also involved in metabolism, DNA, and red blood cell production. Because B12 is primarily found in meat and other animal products-and not in plant foods unless they're fortified-you may need to seek out a daily supplement. Or, you can try getting more naturally by eating these nine foods.