We know that a healthy diet is important for our well-being. But what, exactly, is a healthy diet? Everyone seems to have a different answer: One friend eats like a caveman. Another pal is strictly protein. A third has sworn off of gluten for good. In a world full of countless trendy diets, conflicting advice, and widespread misinformation, it can be difficult to separate food fad from fact. So, for this Cup of Calm, we went straight to the source and asked the experts to answer five common questions about nutrition. Here’s what they had to say:

  1. Is gluten really all that bad?

Answer: No.

Despite the popularity of gluten-free diets, gluten—a protein found in wheat, barley, and rye—is only a problem if you’re part of the 6 percent of the population that has celiac disease, a wheat allergy, or gluten intolerance. In fact, a study published in the medical journal Digestion found that 86 percent of people with self-diagnosed gluten sensitivity can actually tolerate it without any side effects. So, why does this myth persist? Linda Antinoro, a Registered Dietician at Brigham and Women’s Hospital, says that could be because when most people cut gluten, they’re actually cleaning up their diet. “A diet with a lot of refined carbs like cookies, cakes, and white breads—which contain gluten—is not healthy for you.” However, gluten-free products tend to have fewer nutrients and more saturated fat, sugar, and salt than regular food items. You’re better off focusing on adding more vegetables, fruit, and nonprocessed food to your diet, rather than subtracting gluten.

  1. How important is protein, really?

Answer: Very important!

Protein provides energy and helps us feel full. It’s especially impactful at breakfast: A protein-packed breakfast can help you manage your weight, stabilize your blood sugar, and feel focused throughout the day. While protein is vital, don’t go overboard with it. “This is not an open invitation to eat fatty cuts of meat,” says Antinoro. She recommends fish, lean poultry, beans, nut butters, and other low-fat protein sources. Other healthy protein-rich foods include Greek yogurt, cottage cheese, and eggs.

  1. Are five servings of fruits and vegetables a day enough?

Answer: Not quite.

While federal guidelines used to push “Five a Day,” recent research from Imperial College London suggests that ten or more servings of fruits and vegetables a day is optimum to prevent cancer, heart disease, stroke, and even premature death. So, the more servings the better! (Here’s a guide to serving sizes from the American Heart Association.) “I just keep pushing [fruits and vegetables] as much as I can,” says Antinoro. If you’re trying to lose weight, choose more vegetables than fruit and skip the fruit juice, which won’t fill you up and can cause your blood sugar levels to spike.

  1. Are juice fasts good for you?

Answer: It depends.

Nutritionists generally don’t approve of juice fasts because they lack fiber and protein and are not a long-term solution. That said, if it’s a short-lived, temporary practice that you use to jump-start a healthy lifestyle, “it’s probably fine,” says Antinoro. Dr. Adam Perlman, meQuilibrium’s Chief Medical Officer and Co-founder, agrees, but emphasizes the need for a whole foods diet post-fast. “If you do a fast and then go back to the unhealthy, processed food and a sedentary lifestyle, then I don’t think you’re doing much for yourself,” he says. Put another way: “Even if a juice fast gets you rolling, you still have to adopt healthy eating habits,” Antinoro adds.

  1. Should I be eating Paleo?

Answer: Maybe.

The meat-heavy Paleo diet attempts to revive the diet of our ancient, Paleolithic ancestors. Also known as the “Caveman Diet,” it’s been popular for the past decade or so. But is a Paleo diet actually good for you? “I certainly agree that taking sugar out of your diet, by and large, is great,” says Perlman. However, some Paleo guidelines are more controversial—for example, most dietitians are not down with skipping legumes (like peanuts, chickpeas, and soybeans), which are a good source of protein and essential amino acids. At the end of the day, though, both Antinoro and Perlman agree that Paleo is one of the healthier diets of recent years. “Anything that has people doing more fruits, vegetables, and seafood and less processed foods is fine,” says Antinoro. There’s research that supports this, with randomized controlled trials showing that people on the Paleo diet have better glucose control and more weight loss than those on other diets.

Ultimately, the healthiest “diet” will only work if it’s sustainable. Instead of plunging into a restrictive diet, think more broadly about making consistent nutritious choices like avoiding soda and fried foods, swapping salt for spices, and packing each meal with colorful fruits and veggies. The key is to focus on healthy choices that work for you.

Hannah Wallace is a Portland-based journalist and editor who writes about integrative medicine, sustainable agriculture, and wine for Food & Wine, Vogue, Fast Company, and other publications. You can follow her on Twitter or Instagram at @Hannahmw23.