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Considered a cardio-protective diet plan, the Engine 2 diet is essentially a vegan diet without the vegetable oils. Protein comes from pulses and soy foods.

An interesting take on the flexitarian diet, the VB6 stipulates no meat, diary, eggs, or other animal products before 6 p.m., and unrestricted eating in moderation after that.

One of the least restrictive diets, it starts with fruits, vegetables, and whole grains, then permits lean meat, poultry, or fish in moderate portion sizes.

It emphasizes fruits, vegetables, and whole grains, with beans and legumes providing the protein. Variations include an allowance for diary or eggs.

These dietary plans aren’t necessarily vegan. They put plants first, but allow for proteins from fish or animal sources.

It’s based on giving up certain foods for a month to eliminate cravings and reset hormones.

The Mediterranean variant of the paleo diet swaps wild-caught seafood for lean meat.

Mimicking the diet of our caveman ancestors, the paleo diet emphasizes a balance of 30% fat, 35% vegetables (no grains) and 35% protein. It restricts any kind of processed food.

A meal-replacement program that emphasizes reduced calories and six small meals a day.

Highly restrictive, the Dukan diet declares war on both carbs and fats.