How do you compare protein drinks, bars and powders?

Start with the serving size

Labels may give amounts per serving, per container, per 100 g or per 100 ml. To compare products, first make sure you are comparing the amounts you will actually consume.

For example, a bottle with two servings and 12 g of protein per serving contains 24 g if you drink the whole bottle. Calories and other nutrients also double. The serving size on a label is not necessarily a recommended amount.123

Account for what you add

A powder’s label may describe the dry powder, while a ready-to-drink shake includes the liquid. If you mix powder with milk or another ingredient, include its protein, calories and allergens too.

Values per 100 g of dry powder and per 100 ml of prepared drink describe different amounts. One is not automatically more nutritious because its number is higher.123

Read beyond protein

Check the full nutrition and ingredient labels. Depending on your needs, sugars, saturated fat, fibre, sweeteners, added vitamins, minerals or caffeine may matter. If you have an allergy, check the exact label; milk, soy and nuts are examples of ingredients to look for. Labelling rules vary by country. If you use several products, check for repeated ingredients and ask a health professional about possible interactions.

On a US Nutrition Facts label, added sugars are already included in total sugars. For example, “8 g total sugars, including 3 g added sugars” means 8 g in total, not 11 g. Milk or fruit can contribute naturally occurring sugars, and label formats vary by country. “Sugar-free” does not necessarily mean free of calories or carbohydrates. Some sugar alcohols and added fibres can cause digestive symptoms: see why protein products can cause bloating.12378

Does plant-based always mean safe for a milk allergy?

No. A plant-based or vegan label describes the intended product. It cannot rule out a manufacturing error or contact with an allergen. In 2022, a US company recalled two batches of vegan protein powder after a milk-derived whey ingredient was used by mistake. The FDA-hosted company notice says that recall is complete. It is a historical example, not a current warning about every product from that company or a measure of how often errors happen.

If you have a milk allergy, check the full ingredient and allergen information on the exact product each time, including its flavour and formulation. Ask the manufacturer or an allergy specialist if you are unsure. Warning statements and labelling rules vary by country, and the absence of a warning does not guarantee there has been no contact with an allergen.

Check current food-safety notices for your country and the specific batch. The US FDA has a recall list, but says not every recall appears on it. Lactose intolerance and milk allergy are different: see protein products, lactose and milk allergy.456

Compare convenience and cost

A bar is portable, a sealed drink needs no mixing, and a powder needs liquid and a clean container. Comparing the cost of the amount you will use may be more helpful than comparing the price of each tub.

Check whether a drink needs refrigeration before or after opening and how to store a prepared shake. See the storage guide.123

Protein is not a promise

Protein provides building blocks for the body. You can get it from foods as well as supplements. A claim on the front of a pack, or a higher number of grams, does not by itself mean better muscle, weight or health results.

Study results depend on the product, the people studied, their overall diet and their activity. Read what protein-powder studies show. A dietitian or clinician can help with your individual dietary needs.123

After choosing a format

Follow the storage instructions for the exact product: preparation can change how it needs to be stored. See storing powders, shakes and bars. For evidence on training and protein supplements, see do protein powders build muscle?. For help looking beyond a product claim, read how to interpret a study result.