Following a diet high in fat and low in carbohydrates has been shown to help people lose weight. The keto diet also helps people exercise more, control blood sugar, manage chronic diseases, and more. But, just like any diet plan, there are some things to consider before you try it out. This goes for if you have tried it, too. (If you are seeing some warning signs like nausea, headaches, diarrhea, and others, it may be time to stop.) Overall, one thing to think about is your health long-term, and one study just revealed that following a keto diet could hurt your heart.Researchers from National Jewish Health say in the study that a keto diet, as well as an intermittent fasting diet, can contribute to weight loss. "However, these diets also allow consumption of foods that are known to increase cardiovascular risk and are unlikely to be as effective at preventing heart disease as well-established nutritional guidelines currently recommended by health experts," they note. (For more on clean eating, here are the 21 Best Healthy Cooking Hacks of All Time.)The study reviews past findings regarding eating to stay in ketosis. Dr. Andrew Freeman, director of cardiovascular prevention and wellness at National Jewish Health and co-author of the study, says data shows the diet isn't sustainable after a year. Eating a large amount of fat for a long time means possibly eating more saturated fat for a long time. This is bad for the heart and could "lead to stiffening of the arteries, and several studies found that those who eat a keto diet have a greater risk of death."More emphasis on long-term studies is needed to see if the keto diet could hurt your heart, the review says. Only that can determine the real risks and benefits of the diet. In the meantime, if you follow the diet, be sure to avoid artificial sweeteners, hidden carbohydrates, and eat enough vegetables. For more, here are 8 major Mistakes You're Making on the Keto Diet.Dr. Freeman recommends a plant-based or Mediterranean diet instead because those two have shown to improve and could reverse cardiovascular risks. Talk to your doctor to find out what eating plan is best for you and your lifestyle!For more news delivered straight to your inbox, sign up for our daily newsletter!