By Manuel Villacorta, RD

With protein available in so many different forms like tubs of powder, pre-mixed in the supplement aisle, inside protein bars and the like, there’s a lot of confusion about whether or not these products can be used in place of meals. Some people wonder when it’s appropriate to use them at all. If you’re one of these people, let’s investigate.

What Is a Meal Replacement?

Meal replacements are defined as substitutes for solid food and most commonly come in the form of bars and shakes. Since they are usually portion and calorie controlled, some people prefer to use meal replacements as a weight loss tool and some studies have indeed shown that meal replacements can result in successful weight loss. However, some people just use them out of convenience when they don’t have time to prepare a meal.

Ideally, a meal replacement should have 400-500 calories or about the same caloric content as a sensible meal and normally should contain all three macronutrients: protein, carbohydrate and fat. As a dietitian, in my practice I recommend two sensible meals and a meal replacement or two meal replacements and a sensible meal with snacks. This practice has the tendency to promote weight loss while also giving the body proper nourishment.

What Are Protein Supplements?

Protein drinks come in two forms: premixed or protein powder. The premixed drinks are usually what you see bottled up and ready to drink in the grocery store. Protein powder usually comes in tubs or bags and require the user to mix it in water, milk or a liquid of their choice. However, this form of protein is not considered a meal replacement on its own due to it usually being high in protein, but without enough of the other macronutrients.

When is just protein powder appropriate? If you choose to use protein powder as a meal replacement, it is recommended that you add other foods to it. This is because protein shakes should contain a mixture of all macronutrients: protein, carbohydrates and fat. For example, a banana, two tablespoons of peanut butter and a scoop of protein powder is a quick and delicious shake that contains all macronutrients, is within the 300-400 calorie range and would make a great replacement to any meal. A meal like this is a great option for people who don’t always have time to plan meals or those who want a quick breakfast.

In this form, protein powder can also be appropriate before a workout to provide fuel and after a workout to both promote muscle recovery and body replenishment from the effort of physical activity. As a strategy to prevent overeating, I recommend that my clients consume a protein drink before going out to eat or a social gathering that may have less-than-healthful foods. This will keep you satiated without contributing a significant number of calories.

Meal replacements and protein drinks all have their own uses and place in a person’s diet. The key is to use them mindfully and appropriately to further your nutrition goals.