When people fill up on 800 grams of fruits and veggies, they could end up losing weight especially if they choose the lower-calorie options. They'll fill you up and leave less room in your diet for highly-processed, nutrient-poor foods.
While registered dietitian Leslie Langevin, MS, author of The Anti-Inflammatory Kitchen Cookbook agrees that eating more veggies is one way to help with weight-loss, since the fibre and high water content in vegetables helps you feel satiated longer, eating 800 grams of fruits and veggies won't automatically result in losing weight.
If the rest of your diet includes tons of alcohol, pizza, chips, cookies, and other high-calorie processed foods, or you're consuming too much, you won't lose weight.
If you are doing the 800 Gram Challenge in the hopes of losing weight, Leslie said non-starchy veggies are the best choices, since you can eat as many as you want with minimal calories. Go for salad greens like kale, arugula, and spinach, as well as broccoli, cauliflower, carrots, cabbage, bell peppers, cucumbers, courgette, mushrooms, celery, and onions. "The only ones to watch portions on would be potatoes, sweet potatoes, corn, peas, and cooked beans," she said.
As for fruits, registered dietitian Stephanie Clarke of C&J Nutrition, told POPSUGAR in a previous interview, "While the sugar from fruit is different in that it brings along fibre, vitamins, and minerals, too much sugar in any form can cause a steep rise in blood sugar levels that is then followed by a steep crash." So if you're watching your sugar intake, you should choose the low-sugar fruits such as raspberries, strawberries, blackberries, and grapefruit.