Protein Powders May Be Doing More Harm than Good

Jared Hirschfield, National Center for Health Research

Protein powders have become increasingly popular in recent years among a wide range of people — from professional athletes to those too busy to grab a full meal. They assume that supplementing their diet with sports nutrition powders is a safe and easy way to add muscle faster and recover more quickly. Many of these products are advertised as “natural” or “organic” and promise immediate and dramatic results.

But are these supplements actually safe? In addition to protein, these powders often contain potentially harmful chemicals, and some are even contaminated with toxins and metals. How could that be? Under the Dietary Supplement Health and Education Act, no dietary supplements, including protein powders, are regulated by the FDA to make sure they are safe or effective.[1] There is also no requirement that supplements be tested to make sure they contain what the labels say they contain. Research has shown that many dietary supplements sold in major drug store chains, natural food stores, and respected online outlets do not contain what they are supposed to or contain ingredients not listed on the label.[2]

What’s in Your Protein Powder?

When comparing and purchasing sports nutrition powders, consumers should pay close attention to the list of ingredients. Additives, such as caffeine, creatine, and sweeteners, are sometimes in these powders but are not mentioned in advertisements. When consumers are unaware of these additives, they can be especially harmful. For example, consuming several cups of coffee or tea throughout the day in addition to a protein powder that contains caffeine could have unpleasant side effects, including tremors, migraines, and insomnia.[3] Creatine, a popular sports supplement, increases the amount of water in your muscle cells, leading to significant weight gain and putting you at a higher risk for dehydration, stomach pain, and muscle cramping.[4][5] Creatine can be particularly dangerous for people with kidney or liver disease and has not been studied for safety in children or adolescents under the age of 18.[6] In addition, the American Heart Association recommends a daily added sugar limit of 25 to 36 grams, but some protein powders have as much as 23 grams of added sugar per scoop.[7][8] Others contain artificial sweeteners like
sucralose or aspartame, which can be harmful in large quantities. For these reasons, consumers need to know exactly what is in their daily protein shakes and how it may affect their health.

Toxins and Contaminants

Unfortunately, looking through the list of ingredients sometimes isn’t enough. In early 2018, an independent, nonprofit organization, Clean Label Project, released the results of a study in which over 130 of the best-selling protein powders were tested for levels of pesticides, heavy metals, bisphenol A (BPA), and other unsafe contaminants.[9] About three-quarters of the powders tested contained detectable levels of lead and cadmium, both of which can cause permanent health concerns, including kidney and brain damage.[10] About half of the powders contained detectable levels of BPA, which disrupts hormones and is linked to numerous health issues. One product was found to contain over 25 times the regulatory limit of BPA in just one serving.[11]

Unfortunately, “organic” products were no better; in fact, products labeled “organic” contained on average over two times the levels of heavy metals of conventional products.  Many Americans consume these sports nutrition powders as part of a healthy, exercise-filled lifestyle, not realizing that the contaminants have the potential to cause serious and, in some cases, irreversible damage to their bodies.

What Should You Do Instead?

Many Americans think that more protein is better. The recommended daily allowance (RDA) is 0.8 grams of protein per kilogram of body weight.[12] According to this guideline, someone who weighs 140 pounds should consume roughly 50 grams of protein per day, the equivalent of 6 ounces of lean meat, 5 ounces of nuts, or 20 ounces of tofu. Contrary to common belief, consuming much more than recommended amounts of protein can actually have harmful effects on your bones, kidneys, and liver.[13]

Aside from rare cases, no one needs protein supplements to reach their fitness goals. A diet rich in whole foods like legumes, nuts, and soy products provides plenty of protein to build muscle. By maintaining a well-balanced, nutritious diet, you can live healthily while avoiding the hidden ingredients and contaminants of sports nutrition powders.

The Bottom Line

Protein powders often contain hidden ingredients and dangerous contaminants. If you are going to use a protein supplement, remember that these are largely unregulated products. If you experience any unusual side effects, stop using the product immediately and consult with your physician.


[1] “Dietary Supplement Health and Education Act of 1994.” National Institutes of Health: Office of Dietary Supplements (U.S. Department of Health and Human Services).

[2] Thompson, Dennis. “Can You Trust the Labels on Your Supplements?” WebMD. 02 November 2017.

[3] “Caffeine: How much is too much?” Mayo Clinic. 08 March 2017.

[4] Powers, M.E. et al. “Creatine Supplementation Increases Total Body Water Without Altering Fluid Distribution.” Journal of Athletic Training, 38(1).

[5] “Creatine.” Mayo Clinic. 12 October 2017.

[6] “Your Nutrition Game Plan: Answers to Your Top 10 Questions About Creatine.” International Center for Sports Nutrition. 1999.

[7] “Added Sugars.” American Heart Association. 17 April 2018.

[8] “The hidden dangers of protein powders.” Harvard Health Publishing. September 2018.

[9] “2018 Protein Powder Study.” Clean Label Project.

[10] “Heavy Metal Poisoning.” National Organization for Rare Disorders.

[11] “Clean Label Project Protein Powder Study Results 2018.” Clean Label Project.

[12] Pendick, Daniel. “How much protein do you need every day?” Harvard Health Publishing. 18 June 2015.

[13] Delimaris, Ioannis. “Adverse Effects Associated with Protein Intake above the Recommended Dietary Allowance for Adults.” ISRN Nutrition. 18 July 2013.