A new Consumer Reports investigation including tests of 15 protein drinks by an outside lab, reveals some of the drinks may pose health problems over time.
The problems can be serious especially at a consumption level of three or more servings a day -- due to the potential to consume harmful heavy metals and excessive protein.
All of the protein drinks tested by CR had at least one sample containing one or more of the following contaminants: arsenic, cadmium, lead, and mercury, which can have toxic effects on the body, including several organs.
The products, sold as ready-to-drink liquids or powders that are mixed with milk, juice or water to make shakes, attract not just athletes, but also baby boomers, pregnant women, and teenagers looking for a shortcut to a buff body.
For most of the drinks tested, levels of contaminants detected were in the low to moderate range, but levels in three of the products were of particular concern because consumers who have three servings daily could be exposed to levels of arsenic, cadmium or lead that exceed the maximum limits for one or two of those contaminants in dietary supplements proposed by the U.S. Pharmacopeia (USP). The USP is the federally recognized authority that sets voluntary standards for health products.
Exceptions to the regs
Federal regulations do not generally require that protein drinks and other dietary supplements be tested before they are sold to ensure that they're safe, effective, and free of contaminants, as the rules require for prescription drugs. "We need better government oversight and regulation of this product sector, as well as better quality control practices in manufacturing," said Urvashi Rangan, PhD., the magazine's director of technical policy. "Especially for consumers who are using these products regularly -- consuming two or three or more times a day -- there should be better safeguards to ensure the safety of these protein drinks."
Proposition 65, a California State law, mandates that manufacturers notify consumers when products contain toxic substances at levels the state says pose even a low cancer or reproductive risk. Eight of the 15 protein drinks tested by Consumer Reports fall into this category due to their elevated levels of lead. "Those products should be required to carry a warning label if they were sold in California," said Rangan.
Too much of a good thing
Consuming excess protein can also cause health problems. Teenagers who want to look like the sculpted images they see in fitness magazines are especially vulnerable to the marketing messages trumpeted by the makers of protein drinks. Enticed by the promise of "hope in a can," teenagers tend to overuse the products, assuming that if one scoop is good, then four to five would be even better. A 2005 study published by the American Academy of Pediatrics found that protein powders and shakes were the supplements most commonly used by those aged 12 to 18.
Pregnant women are also vulnerable because heavy metals can pose risks to a developing fetus or a nursing baby. Some protein drinks market directly to these groups while others warn they are not suitable for people under 18 years of age or that pregnant women should consult a physician before use.
What the tests found
Consumer Reports purchased 15 protein powders and drinks mainly in the New York metro area or online and tested multiple samples of each for arsenic, cadmium, lead, and mercury. The levels discussed here are based on three servings per day, an amount that experts say is common. The results showed a considerable range, but levels in three products were of particular concern:
• Three daily servings of the ready-to-drink liquid EAS Myoplex Original Rich Dark Chocolate Shake provide an average of 16.9 micrograms (ug) of arsenic, exceeding the proposed USP limit of 15 ug per day and an average of 5.1 ug of cadmium, which is just above the USP limit of 5 ug per day.
• The samples of Muscle Milk Chocolate powder contained all four heavy metals, and levels of three metals in the product were among the highest of all products tested by Consumer Reports. Average cadmium levels of 5.6 ug in three daily servings exceeded the USP limit of 5 ug per day, and the average lead level of 13.5 ug also topped the USP limit of 10 ug per day. The average arsenic level of 12.2 ug was approaching the USP limit of 15 ug per day.
• Muscle Milk Vanilla Crme contained 12.2 ug of lead in three daily servings, exceeding the lead limits, and 11.2 ug of arsenic.
The CR investigation notes that cadmium raises special concern because it accumulates in and can damage the kidneys, the same organs that can be damaged by excessive protein consumption. And it can take 20 years for the body to eliminate even half the cadmium absorbed today.
How much protein?
Only one of the products tested by Consumer Reports, Six Star Muscle Professional Strength Whey Protein, specifies a maximum daily intake. Others use vague language that could encourage a high level of consumption. Consuming excess protein can also pose health problems, including diarrhea. Although protein is needed for bone development, excessive protein over the long term might also cause calcium to be excreted from the bones, increasing the risk of osteoporosis. And for diabetics or others with kidney problems, it can lead to further complications.
The magazine's investigation notes that consumers can roughly calculate how many grams of protein they need by multiplying their body weight by .4. For athletes, the general rule of thumb is about one gram of protein per pound of body weight per day.
The report provides several examples of better, cheaper ways to bulk up. Case in point: a sandwich with three ounces of chicken and an eight ounce glass of whole milk provides about 40 grams of protein, which is more than half the 72 grams needed by a 180-pound person and most of the 48 grams required by someone weighing 120 pounds.