Here's some info I found online about Protein powders:
Protein powder: What Ingredients to Look For and associated Risks
Some products use additive to enhance the flavor, mix-ability, texture, longevity, convenience to transport, or just to bulk the product up and make it cheaper to produce – think popular lines like Muscle Milk, Apex, and Vi. When reading labels, it’s valuable to know that ingredients are typically listed in the order of the highest amount used in the product to the least amount.
Aspartame and Sucralose – Sucralose is sometimes sold as “Splenda”, both are sweeteners containing no calories and are sweeter than sugar. There may be a link between sucralose and leukemia in mice, so its safety rating has changed from “Safe” to “Avoid.” Regarding Aspartame in 2007 it was found that long-term exposure to low doses of aspartame increased cancer in rats.
Maltodextrin – Maltodextrin is an artificial sugar that has a mild, sweet taste. It’s also known as a polysaccharide, or chain of sugars, and is created by applying acids or other enzymes to cornstarch. Maltodextrin is actually a term that applies to any starch hydrolysis product containing fewer than 20 glucose units. Therefore, maltodextrin refers to a family of products rather than one specific product.
It has side effects and health risks similar to most food additives. These include allergic reactions, unexplained weight gain, bloating, and flatulence. Specific allergic reactions include rash, asthma, itching, and difficulty breathing. Wheat-derived maltodextrin may pose health concerns for individuals with celiac disease because it contains gluten. However, in most cases the maltodextrin production process completely removes the protein from the wheat resulting in a gluten-free wheat-derived maltodextrin.
Soy Lecithin – This additive is extracted from soybeans, either mechanically or chemically, using hexane. It’s actually a byproduct of soybean oil production. It can cause side effects such as diarrhea, nausea, abdominal pain, or fullness. Soy lecithin has been linked to negative effects on fertility and reproductionand there are links to a promotion in the risk of cancer.
Xanthan Gum – Xanthan Gum is made by fermenting corn sugar with a bacteria. Xanthan Gum can be derived from a variety of sources such as corn, wheat, and soy. Individuals with an allergy to such sources should avoid foods containing Xanthan Gum. As a carbohydrate with 7 grams of Fiber per tablespoon, it may cause bloating in some people.