Whether it's for weight loss, weight maintenance or convenience, meal-replacement shakes are a viable option and are usually a good source of essential vitamins and minerals. However, as a processed food, your meal-replacement drink may contain ingredients you're trying to avoid, such as aspartame or MSG. Reading food labels and being able to identify them in the ingredient list can help you avoid these unwanted ingredients.

About Aspartame

Aspartame is a sugar substitute that's 200 times sweeter than sugar and may be found in meal-replacement shakes as a way to save calories without losing sweetness. The sugar substitute has been extensively studied and is considered a safe ingredient by the U.S. Food and Drug Administration. But there are concerns that aspartame may have an impact on neurological health or cause cancer, according to the Center for Science in the Public Interest, prompting some consumers to avoid it.

About MSG

MSG, or monosodium glutamate, is added to foods to enhance flavors. It works better in savory foods than sweet, so you might not find it as MSG in your sweet meal-replacement shakes, but it might be present as part of another ingredient. As with aspartame, MSG is considered a safe ingredient by the FDA. Even so, some people are sensitive to the food additive when consumed in large amounts and may experience nausea, headaches, weakness or a burning sensation.

Using the Food Label

If a meal-replacement drink contains aspartame, it must be listed in the ingredient statement on the label. The product must also contain a statement in bold lettering on the label that it contains phenylalanine, which is a byproduct of aspartame and must be avoided by people with the metabolic disorder phenylketonuria.

Like aspartame, MSG must be listed in the ingredient statement as monosodium glutamate if it's present in the shake. But you also want to avoid meal-replacement shakes that contain hydrolyzed vegetable protein, protein isolate, autolyzed or hydrolyzed yeast, soy extract and yeast extract when you're trying to avoid MSG. These ingredients are all natural sources of the flavor enhancer.

Make Your Own

One way to safely avoid both aspartame and MSG without having to read labels is by creating your own meal-replacement shake. For example, you can blend together plain Greek yogurt with mango, pineapple and kale for a sweet and healthy meal. Or try almond milk, almond butter, banana, blueberries and spinach. While making your own meal-replacement shake helps you control the ingredients, they may not contain the same amount of vitamins and minerals as your packaged shake. Consult your doctor about your diet and whether you might benefit from a multivitamin supplement.