I’m a dietitian. I’ve worked with countless individuals and patients for over 12 years. They all have a few things in common: They want to be healthy, look their best, and reduce or get off their medications. I’ve seen some of the sickest patients, including those needing organ transplants. I’ve also seen some of the healthiest, like those looking to run a marathon.

I’ve seen people try every kind of diet you’ve heard of: paleo, Atkins, the Zone diet, gluten-free, even the blood-type diet. The problem is that none of these diets seem to work long-term. People frequently go on them to lose weight or to feel better but find it difficult to stay on them for life. They are often too restrictive. Not only that, but they frequently don’t fix the underlying problem or illness.

Yet, there is a lifestyle diet, one that I’ve discovered works well for most people—including me, an athlete, a dietitian, a mom, and someone who just wants to be her healthiest self. That diet is a plant-based diet. A plant-based diet is simple: a diet that’s full of fruits, vegetables, legumes, nuts, and seeds, and low in animal products.

I first went on a plant-based diet back in 2002 while taking a Cornell plant-based nutrition course, which was run by the encyclopedia of plant-based eating himself, T. Colin Campbell. I primarily did it because I learned of all the health benefits of going on a plant-based diet.

Then, while doing my doctoral research in climate change and food security, I discovered how our diet also affects the health of our home, planet Earth. I discovered that a typical Western diet, one that is heavy in meat, dairy, and other animal products, also has a very high carbon and water footprint, significantly contributes to climate change and land degradation, and harms the oceans. These in turn can negatively affect our food supply, the air we breathe, the spread of disease vectors (think: mosquitos), and ultimately our health.

In the 14 years since I first adopted a plant-based diet, I’ve been healthier than ever. I train for triathlons. I swim one or two miles at a time and do long cycling sessions, and do so with energy, with stamina, and at peak performance. I’ve never been leaner, I’ve never been stronger, and I’ve never been healthier. In fact, more and more athletes are starting to see the benefits of a plant-based diet, too.

And here’s the best part: The reasons to go plant-based are not mutually exclusive. We can eat a healthy plant-based diet for ourselves and for the environment, because it’s simply good for both. What’s more, a plant-based diet works well for almost anyone and offers innumerable benefits. (There are some diseases that require extra dietary care, such as kidney disease, liver disease, and others; if you have one of these or another chronic condition, consult with a dietitian or physician before changing your diet.)

1. Plant-based diets help prevent chronic diseases like diabetes, heart disease, and cancer.

In countries and cultures where the majority of people eat a plant-based diet, the rates of chronic disease such as diabetes, cancer, obesity, and heart disease are extremely low. For individuals who already have diabetes or heart disease or are obese, switching to a whole-foods, plant-based diet can help them reverse or even rid themselves of these diseases. I’ve seen it happen, and the evidence exists. The movie Forks over Knives does a great job of detailing this science, as does the famous epidemiological China Study.

2. Eating mostly plants can improve your skin.

Fruits and vegetables house a slew of vitamins such as A, C, E, and K. They also provide us with antioxidants and phytochemicals or plant nutrients like resveratrol, anthocyanin, and lycopene, to name a few, that have been shown (some more than others) to be beneficial for skin health, collagen production, and may even reduce the risk of skin cancer (though, for that, staying out of the sun is still the best choice).

What’s more: The high water content of fresh fruits and vegetables, fiber in whole grains, and the healthy fats of legumes, nuts, and seeds all promote healthy skin by keeping us hydrated and providing the essential nutrients that our bodies need.

3. A plant-based diet supports good gut health.

Evidence suggests that diets that are low in plants and high in animal products not only increase inflammation in our bodies, but disrupt the healthy flora of our guts—possibly promoting obesity, gastrointestinal problems, and even colon cancers. If, instead, we eat diets that are high in fiber—particularly high in resistant-starches, coming mostly from plant-based whole foods like grains, seeds, and legumes—we can increase the healthy bacteria in our guts and not only feel better but reap the benefits of a harmonious microbiome.

4. A plant-based diet makes weight control significantly easier.

Eating heaping platefuls of produce, healthy plant-based fats (including olive oil, avocado, nuts, and seeds), and plant-based proteins (including legumes, soy, and protein-rich grains like quinoa, farro, and bulgur) makes it easier to maintain your weight and lose excess weight in a healthy way that doesn’t involve strict calorie-cutting.

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So, what’s the best way to start a plant-based diet?

The best way to ease into it is to begin with some easy-to-make substitutions.

Here are a few examples:

• Instead of cereal and cow’s milk for breakfast, try cereal and soy milk, almond milk, or other non-dairy milk.
• Instead of spreading butter on your bread, try delicious and rich avocado.
• Instead of meat at your next meal, try a delicious plant-based alternative such as edamame, spiced-grilled tofu, quinoa, beans, or “faux-meats” like seitan.
• Make scrambled tofu with sautéed vegetables instead of scrambled eggs.
• Have a whole-grain panini with hummus, grilled eggplant, zucchini, and other vegetables.
• Try a Portobello mushroom burger with all the fixings instead of a meat burger.
• Instead of cow’s-milk yogurt, try non-dairy yogurt.

Most importantly, just start somewhere and have fun with it! Be open to trying new fruits, vegetables, and whole grains. You might just be surprised at how much you like the various textures, tastes, and colors you find. You might also be pleasantly surprised by how you look and feel.