Protein is a necessary macronutrient. It makes up the bulk of your muscle tissue and plays a vital role in cellular function and metabolism. Unfortunately for dieters, protein in the form of animal matter often comes with a healthy dollop of fat, so some calorie counters and bodybuilders turn to protein supplements and shakes to increase intake without packing on the pounds. Synthesizing the protein that goes into these powders may have its own issues, however, according to a 2010 Consumer Reports study.
Protein powders are promoted more as a muscle-building supplement and workout aid than weight loss remedy, but they are used frequently for both purposes. Building muscle mass is partly destructive and partly reconstructive. Strained muscles suffer microscopic tears in the fibers. When the body sends in the troops to repair these tears, they do so by manufacturing more muscle tissue. Protein powder makers recommend drinking the supplements shortly after lifting weights to give the body the building blocks it needs for this process.
Most commercially available protein powders derive their protein content from whey, the liquid byproduct of cheese production. There are alternative formulas including soy and other plant-based proteins, but these generally contain fewer grams per serving than the whey varieties. Consumers with allergies should read labels carefully to determine the source of the protein in the powders.
In 2010, Consumer Reports, the magazine published by non-profit advocacy group Consumer Union of the U.S., Inc., printed the results of their survey of 15 popular protein powders. They found that at least one item from each product line contained detectable levels of cadmium, arsenic, lead or mercury. The three most toxic brands contained levels of heavy metal toxicity above the safe allowable limits proposed by U.S. Pharmacopeia when used as directed.
Manufacturers pushed back on the report, citing independent analysis by non-profit NSF International, a non-governmental organization that conducts third-party testing of food safety. According to NSF, the products in question passed their own standard called the American National Standard for Nutritional/Dietary Supplements, or NSF/ANSI. Consumer Reports counters that there is significant variation between samples even within a given product line, and one satisfactory sample does not exonerate the entire line.
Consumer Reports outlined the danger of sustained, low-level heavy metal toxicity noting that the substances included in the study -- arsenic, lead, cadmium and mercury – remain embedded in soft tissue for long periods, so continued exposure could result in higher levels of toxicity overall. Additionally, there is a segment of the health food industry that has long lobbied against aspartame, an artificial sweetener deemed safe by the U.S. Food and Drug Administration and their counterpart in the European Union for decades. Mike Adams, editor of Natural News, and many others in the anti-aspartame campaign, claim that formic acid and formaldehyde, two byproducts of aspartame synthesis in the body, can cause migraine headaches, muscle tremors and vision problems. The U.S. Environmental Protection Agency lists formaldehyde as an environmental toxin.