Can I eat too much protein? Experts answer your questions about the popular supplement | Health and wellness

If our protein powder taste test taught us anything, it’s that these supplements are confusing.

Although both herbal and whey powders are popular, we opted for whey, given its rising prices and popularity (and the former’s higher lead risk).

What started as a simple mission to find the best-tasting powders quickly led us down a rabbit hole, wondering, “What does NSF certification mean?” and “Is organic whey really better?”

To further muddy the waters, the U.S. Food and Drug Administration does not test protein powders for safety, particularly if they contain heavy metals such as lead. They also don’t verify marketing claims promising improved muscle growth or recovery.

So, to answer our most pressing questions about protein, we interviewed four registered dietitians.

Read the story: The 10 Best (and Worst) Whey Protein Powders – Tested

Meet the experts

• Nancy Rodriguez, RD, FACSM and Professor of Nutritional Sciences at the University of Connecticut

• Jamie Nawater, RDN with over a decade of experience

• Nyree Dardarian, RDN, LDN and clinical assistant professor at Drexel University

• Kacie Vavrek, RD at The Ohio State University Wexner Medical Center

Responses have been edited for clarity and length.

Lauren Gould: What ingredients should we avoid?

Kacie Vavrek: While there is no single ingredient that everyone should avoid, some people may want to limit added sugars, excessive sugar alcohols (like erythritol or sorbitol), or artificial sweeteners if they cause digestive issues.

Nyree Dardarian: Every time I see the words “proprietary blend,” I roll my eyes a little. Just tell me what’s in it. I’m also not a fan of products that contain more than 100% of the recommended daily allowance in a bunch of vitamins and minerals, unless you actually need them.

Jamie Nawater : There’s no reason to avoid trace minerals in protein powders in normal amounts, but most people don’t need their protein powder to be supplemented with trace minerals.

LG: You recommend third-party certified protein powders. Which certifications are best?

JN: Look for certifications like NSF Certified for Sport, Informed Sport, or USP Verified. These programs help confirm that the product contains what the label claims and is tested for contaminants. Sports certifications such as NSF Certified for Sport also detect banned substances.

ND: Third-party testing is a good sign, but it doesn’t make a product bulletproof.

LG: Is organic whey better than regular whey?

ND: Don’t automatically assume that organic means healthier or better.

JN: Organic whey is a personal preference, but a protein powder doesn’t have to be nutritious. I would prioritize certification by an independent third party over an organic label.

KW: Organic protein powders don’t necessarily provide more protein or better muscle-building benefits than non-organic whey. If budget is a concern, choosing a high-quality, third-party tested whey protein is usually more important than whether it’s organic.

LG: Is it possible to have too much protein powder?

Nancy Rodriguez: If you take five tablespoons of protein powder a day, you won’t assimilate all of those amino acids into your body and live happily ever after. Your body will store excess nitrogen and the only way to get rid of it is to exercise the liver and kidneys.

When we conducted our studies with elite endurance athletes, we always made sure they also drank enough water. Because if they were going to use protein for fuel, we wanted to help their kidneys clean themselves.