To kick-start your metabolism, eating breakfast is key. It not only fills you up to help prevent mindless snacking on unhealthy noshables, but it also energizes you for calorie-burning workouts. Smoothies are one of the best breakfasts you can have, because you can throw just about anything healthy into your blender, and all you'll taste is the fruit. To maximize your weight-loss potential, add these ingredients to your smoothies.
Related: 5 Reasons Smoothies Help You Drop Pounds Fast 
The key to weight loss is filling up on low-cal foods that are high in fiber to keep you satiated longer. Flaxseeds contain both soluble and insoluble fiber, and when ground into flax meal and added to a smoothie, you'll hardly taste it. As a bonus, flax also offers essential omega-3 fatty acids. Try this pear berry weight-loss smoothie  that offers almost 20 grams of fiber.
While fruits offer tons of fiber, berries are your best bet. Try this chocolate banana berry protein smoothie  made with strawberries, blueberries, and raspberries. The almost 11 grams of fiber will keep that "I'm full" feeling going strong to discourage mindless snacking. It also doesn't hurt that eating blueberries helps diminish belly fat .
Protein in the morning is a must if you're trying to lose weight, because it offers you sustained energy to prevent the morning blahs from forcing you to reach for a high-sugar pick-me-up. While protein powder is a great way to increase the fiber in your smoothie, it can cause bloating or gas if you're not used to it. Tofu is another source of protein, but it's easy to digest, and since it's virtually flavorless, it's the perfect smoothie ingredient. Here's a smoothie that tastes like a vanilla milkshake  made with soft tofu, soy milk, and peanut butter that offers over 17 grams of protein.
Related: This Pumpkin Pie Pudding Is Made With Tofu! 
Don't knock it till you try it! Adding cannellini beans to your smoothie seems like a weird idea, but just like tofu, it adds a creamy consistency without any flavor. But what's really important is the amount of fiber it offers to keep you full and satisfied all morning long. Give this metabolism-boosting smoothie  a try, and you'll wonder why you didn't start adding beans to your blender sooner. It also has a sprinkle of cinnamon for calorie-free flavor and to speed up your metabolism.
Greek yogurt provides a decent amount of calcium and protein, both of which can aid in weight loss. It's an easy ingredient to add to smoothies, and to save even more calories, go for plain instead of flavored. This flat-belly smoothie  is also made with pineapple, which contains an enzyme that helps ease digestion and banish bloat.
Fats have a bad reputation, but eating the right kinds — monounsaturated fats (MUFAs) — may actually quiet hunger. This clear-skin smoothie  is made with ripe avocado, a great source of oleic acid. Be careful not to overdo it on this healthy ingredient, as it's also high in calories.
Related: Swap Avocado For Butter in Your Baked Goods to Save Calories 
A mild-tasting green, throw in a big bunch of baby spinach (kale works too). You'll be increasing the fiber to help you stay full and to also prevent constipation, which won't help you lose weight but will make your belly look flatter. Mix up this chocolate banana cashew smoothie , and aside from spinach, it's also made with chocolate soy milk to satisfy your sweet tooth and to prevent you from devouring a high-calorie dessert bomb later.
A source of protein and healthy fats — that's two reasons walnuts can help you drop pounds. Try them in this cherry berry ginger smoothie , which also contains satiating, fiber-rich kale; cherries; strawberries; and wheat germ.
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