Whether you're looking at a Paleo, vegan, or clean eating plan, these features are a must for all diets

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While proponents of various healthy diets like to make their plans seem really different, the truth is that a healthy vegan plate and a Paleo diet actually have quite a bit in common-as do all truly good diets. How do you know if a plan qualifies as a "good" one for weight loss? (Psst! Definitely opt for one of The Best Diet for Your Health.) To start, ask yourself these four questions, says Judith Wylie-Rosett, Ed.D., head of the division of health promotion and nutrition research at Albert Einstein College of Medicine.

1. Is it too good to be true or too bad to believe?

2. Is there strong evidence that it works?

3. Is there a possibility for harm?

4. Is it better than the alternative?

In addition to the right answers to those questions, here are four features Wylie-Rosett says all good plans have.

Lots and Lots of Vegetables (Especially Leafy Greens)

That's what most American's are missing, says Wylie-Rosett. Not only are greens low-cal and filling, these antioxidant rich foods have tons of health-promoting pigments, as well as vitamins and minerals. If you need help cooking them, check out 16 Ways to Eat More Veggies

A Focus on Quality

How much you eat matters, but what you eat matters too, so choose a diet that encourages choosing good-quality foods. That doesn't necessarily mean all organic and fresh, though: While organic has its advantages, conventional healthy foods (like whole-wheat pasta) are still better than unhealthy organic ones (like organic white bread), and frozen veggies can be just as good as fresh.

A Plan to Fill in Nutrient Gaps

A good diet will address any possible nutrient shortfalls, says Wylie-Rosett. For example, if a plan cuts out grains, it should include other sources of nutrients like magnesium and fiber. Similarly, plant-based plans should advise how to get enough vitamin B12, vitamin D, and calcium. If you're eating vegan, try one of these 10 Flavor-Packed Tofu Recipes for Weight Loss.

Fewer Processed or Convenience Foods

The easiest way to cut back on sodium, refined carbs, and sugar is to eat fewer or none of these foods-and that's a strategy that most popular diets endorse. A focus on whole foods and cooking your own food will not only help you slim down, it'll reduce your disease risk as well.