Cold water immersion (a.k.a., “ice baths”) has become a popular method amongst exercise enthusiasts and athletes to enhance recovery after an intense training bout. The strategy involves exposing either the trained limb or the whole body to very cold liquid temperatures. According to p...
Brad Schoenfeld, Ph.D, C.S.C.S., is an internationally renowned fitness expert and widely regarded as one of the leading authorities on body composition training (muscle development and fat loss). He is a lifetime drug-free bodybuilder, and has won numerous natural bodybuilding titles.
I’ve received a flood of emails recently about a recent Consumer Reports study that found various protein supplements contained potentially unsafe levels of arsenic, cadmium, mercury, and lead. The story was picked up by CBS Early Show. You can view the CBS clip for yourself here:
Before tackling the specifics of the Consumer Reports study, I feel compelled to address the spotty reporting done by CBS on the subject. First off, the hidden-camera footage of the individuals who work in supplement stores was patently disturbing. Clearly these people have no concept as to human physiology. But while this makes for good theater, should it really come as a surprise? The vast majority of supplement store workers are nothing more than low-paid clerks with no formal training in exercise or nutrition–certainly not the kind of individuals you’d want to seek out for advice on the efficacy of something you intend to put into your body. (Would you ask the secretary in your doctors office her opinion on whether or not you should take medication?).
Let’s get things straight: taking more protein than your body can utilize (generally about one gram per pound of body weight for someone who engages in intense strength training) will not result in any additional increases muscle mass. The human body cannot store excess protein for future use. Period. The moral of the story: don’t ask a store clerk for advice on supplementation–be an educated consumer and do your own research.
The CBS report also makes several unsupported claims that need clarification. For one, protein intake has not been shown to lead to dehydration. In a recent review on the subject, Martin and colleagues (2005) trace the genesis of this erroneous claim to an unsubstantiated extension of a 1954 review on nitrogen balance. Fact is, the belief has no credence. Current literature shows no evidence of dehydration associated with protein intake in healthy individuals. It’s an old-wives tale that needs to be put to rest.
Moreover, the claims that increased protein consumption heightens a person’s risk for osteoporosis are equally unsubstantiated. The overwhelming body of research shows that protein intake has no negative effects on bone loss (Spencer et al., 1988; Bonour, 2005). In fact, studies suggest that protein intake is actually positively correlated with bone mineral density of the femur, lumbar spine and distal radius (Cooper et al., 1996; Geinoz et al., 1993). I will elaborate on this subject in a future blog post but, in the meantime, read the referenced studies to form your own opinion.
Okay, let’s move on to the Consumer Reports investigation into protein supplements. According to their tests, heavy metals were present in all 15 of the protein supplements evaluated. Three products–EAS Myoplex Original Rich Dark Chocolate Shake (ready-to-drink liquid formula), Muscle Milk Vanilla Crème, and Muscle Milk Chocolate powder–were found to exceed limits established by the United States Pharmacopeia (USP) in at least one of the metals. A fourth product, Muscle Milk Nutritional Shake Chocolate (ready-drink liquid formula), was found to approach the USP daily limit for arsenic.
Now before jumping to conclusions and swearing off consumption of any protein supplement, it should be noted that, in their written findings, the Consumer Reports team states the “concentrations in most products were relatively low.” It is only “when taking into account the large serving size suggested, the number of micrograms per day for a few of the products was high compared with most others tested.” Apparently the serving size alluded to here is three per day. While I’m sure there are some who do scarf down such hefty amounts of protein supplements, it is much more common to use them as a pre- or post-workout drink in a single daily serving. Thus, the conclusions drawn in the study seem to be misleading for a majority of protein supplement consumers.
Consumer Reports also did not disclose its testing methods used in the evaluation. Although Consumer Reports is generally regarded as a reputable organization, their lack of disclosure here does not allow interested parties to scrutinize the accuracy of their findings. As someone who serves as a reviewer for several peer-reviewed journals, I can tell you that such an omission would automatically preclude publication as a scientific study. Does this nullify the results of the tests? Certainly not. But it does raise a red flag and leave open the possibility that results may be flawed.
In case you dismiss such a possibility outright, I encourage you to read the Statement Regarding Consumer Reports Article on Protein Drinks issued by NSF International, a not-for-profit, non-governmental organization and leader in product certification for public health and safety. In their statement, NSF claims that the Consumer Reports study, “…omits critical information about the laboratory that performed the test and its accreditation qualifications. ISO 17025 accreditation is critical for any laboratory testing for heavy metals in dietary supplements and nutritional products.” Interestingly, testing carried out under NSF supervision found that, “Muscle Milk Chocolate and Muscle Milk Vanilla Crème have been certified to NSF/ANSI Standard 173. The samples analyzed met the maximum acceptable limits of the standard based upon our validated test methods.” Who is right here? Who knows? But the waters surrounding the topic have been muddied. Clearly more testing is needed to bear out the facts.
Still and all, it is hard to deny that the findings of the Consumer Reports study on protein supplements are alarming in the very least. More than anything, the study highlights the fact that the industry remains virtually unregulated. Unless and until a private organization decides to investigate a product’s ingredients, supplement manufacturers are basically left on their own to comply with proper standards. What to do? Your best bet to ensure quality is to look for supplements that bear the “USP Verified” seal. This shows that a product has met the scrutiny of the USP Dietary Supplement Verification Program, where supplements are tested for quality, purity, and potency. USP verification ensures that 1) products contain the ingredients listed on the label, in the declared potency and amounts; 2) do not contain harmful levels of specified contaminants; 3) will break down and release into the body within a specified amount of time; and 4) have been made according to FDA current GMPs using sanitary and well-controlled procedures. Submission to the USP program is voluntarily, and only a handful of companies choose to comply. You might pay a little more for those who do, but considering what’s at stake, it’s worth the peace of mind.
Stay Fit!
Brad
Bonjour JP. Dietary protein: an essential nutrient for bone health. (2005). J Am Coll Nutr. 24(6 Suppl):526S-36S.
Cooper C, Atkinson EJ, Hensrud DD, et al. (1996). Dietary protein intake and bone mass in women. Calcif Tissue Int. 58:320–5.
Geinoz G, Rapin CH, Rizzoli R, et al. (1993). Relationship between bone mineral density and dietary intakes in the elderly. Osteoporos Int. 3:242–8.
Martin WF, Armstrong LE, Rodriguez NR. Dietary protein intake and renal function. Nutr Metab (Lond). 2005 Sep 20;2:25
Spencer H, Kramer L, Osis D. (1988). Do protein and phosphorus cause calcium loss? J Nutr. 118(6):657-60.
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