The researchers hypothesize that participants who abstained from animal products dropped significantly more pounds since plant-based foods include loads of filling fiber and slow-to-digest complex carbs. Though more research is needed to confirm these results, the study authors write, "Vegetarian diets appeared to have significant benefits on weight reduction compared to non-vegetarian diets."
Like protein, fiber slows the rate at which your body plows through carb calories so you feel full for longer and maintain steadier blood sugar levels, one reason why research consistently links fiber intake to weight loss. That means fibrous whole grain bread tends to be a better choice than white bread and also explains why fruits, which contain fiber and valuable vitamins in addition to sugar, beat straight-up candy every time.
Whole foods include fruits, vegetables, beans, nuts, seeds, whole grains, eggs, seafood, chicken and so on. Food philosophies may differ around which of these foods to emphasize, but that’s okay, since the evidence shows that there isn’t a single best way to lose weight. The goal is to select an approach that feels sustainable to you. If you can easily live without pasta, perhaps a low-carb method centered around veggies and quality proteins, like seafood, chicken, and lean beef would be a good fit. Vegans and vegetarians can lose weight by choosing fruits, vegetables, whole grains and plant proteins. Nut lovers may do well shedding pounds with a Mediterranean-style menu. Whatever diet appeals to your appetite and way of life, focusing on whole foods is something that all plans promote.