For a while, everyone and their mother were saying no to meat and dairy—you can thank Michael Pollan, Mark Bittman, and maybe the invention of Coconut Bliss for helping to turn veganism from a fringe movement to a trendy diet among celebrities and hipsters. Of course, science has also been on the side of eating fewer animal products: Compared to the average omnivorous way of eating, plant-based diets tend to be higher in fiber and antioxidants and lower in unhealthy fats, not to mention significantly better for the environment.

Yet there are some drawbacks to being vegan, such as zombie-like energy levels and major difficulty getting enough protein without a degree in plant biology. That's why some former veg heads have said goodbye to a strict diet of tofu and veggies—and hello to eating lean protein, eggs, and even the occasional buttery pastry. Here, why seven high-profile former vegans gave up the ethic for animal foods: