"Clean" isn't a regulated term, so on a protein tub it can mean almost anything. In practice, a clean protein powder is one with a short, recognizable ingredient list, no unnecessary sweeteners or fillers, responsibly sourced protein, and independent testing to show it contains what the label says and not much else. Here's a quick checklist.
Why read the whole ingredient list?
Flip the tub over and read everything, not just the front. Ingredients are listed by weight, so the first few should be the protein itself. If the list runs long with ingredients you don't recognize, look them up. Common add-ins that have nothing to do with protein include gums and thickeners, fillers such as maltodextrin, and sweeteners.
What sweeteners and sugars should you watch for?
Many powders that taste like a milkshake get there with added sugar or sugar substitutes. High-intensity sweeteners such as sucralose and acesulfame potassium are FDA-approved, but some people prefer to avoid them. Sugar alcohols can upset your stomach: FDA rules require foods likely to supply 50 grams of sorbitol a day to warn that "excess consumption may have a laxative effect." Check the Nutrition or Supplement Facts panel for added sugars too.
Do protein powders contain heavy metals?
Some do. When Consumer Reports tested protein drinks, every product had at least one sample containing arsenic, cadmium, lead or mercury, and three products would exceed proposed U.S. Pharmacopeia limits at three servings a day. A later risk assessment of the published data concluded that typical intake was unlikely to cause harm, so this isn't a reason to panic. It is a reason to buy from brands that test every batch and publish the results.
Does the protein's source matter?
It does, for both dairy and plant proteins. Conventional dairy cows may be given the hormone rbST, which the FDA has approved and considers safe in milk, but which the European Union does not allow. If you'd rather avoid it, organic certification is the simplest filter: USDA organic standards require organic dairy animals to eat 100% organic feed, and crops must be grown without prohibited substances, with genetic engineering not allowed.
For plant proteins, organic certification likewise means the pea, rice or other crops were grown under those rules rather than with conventional pesticides.
What about trans fats?
This used to be on the list, and it's largely solved. The FDA determined in 2015 that partially hydrogenated oils, then the main source of artificial trans fat, are no longer "generally recognized as safe," and manufacturers could not add them to foods after June 2018, with a final compliance date of January 2021. It's still worth a glance at the label, but it's no longer a common problem in protein powders.
A quick checklist for a clean protein powder
- Choose plant-based if dairy doesn't agree with you.
- Read the whole label, not just the front.
- Check added sugars and the type of sweetener.
- Look up any ingredient you don't recognize.
- Look for USDA Organic certification and batch testing with published results.
For the full version, including how to compare plant proteins and read testing certifications, see how to choose a clean plant-based protein powder. Or skip the homework: So Lean & So Clean is organic and vegan, with 23g of complete plant protein from pea and rice, no added sugar and no artificial sweeteners, fillers or gums. You can see how we test on our 5 Nation Standard page and look up certificates of analysis.
