Written by the Spacemilk team · Last updated October 2026

An allergen-free protein powder, in practice, is one whose ingredients contain none of the nine major food allergens and whose maker controls and tests for cross-contact. The front of the tub won't tell you that on its own. The FDA defines "gluten-free," but not "allergen-free," "dairy-free" or "nut-free," and "may contain" warnings are voluntary. Read the ingredient list and the allergen statement, then look for published, per-batch test results. If you've had a severe reaction before, talk to your allergist before trying anything new.

What are the nine major food allergens?

In the United States, the major food allergens are milk, eggs, fish, crustacean shellfish, tree nuts, peanuts, wheat, soybeans and sesame. Sesame became the ninth under the FASTER Act, signed in April 2021, and the change took effect on January 1, 2023 (FDA). Packaged foods must declare these allergens when they're ingredients.

That matters to a lot of people. Food Allergy Research & Education (FARE) estimates that more than 33 million people in the US live with at least one food allergy (FARE, 2023).

One note on wheat and gluten: a wheat allergy is an immune reaction to wheat proteins, while celiac disease is a reaction to gluten, which is also found in barley and rye. A "gluten-free" label speaks to the second.

What do "allergen-free" and "dairy-free" mean on a label?

Less than most people assume. Here's what's defined and what isn't:

• "Gluten-free" is defined. Under the FDA's 2013 rule, any unavoidable gluten in a food labeled gluten-free must be under 20 parts per million (FDA).
• "Dairy-free" isn't. The FDA says it does not define "dairy-free" or "milk-free." When state regulators, working with the FDA, sampled 210 chocolate products labeled "dairy free," 13 tested positive for milk (FDA, 2024).
• Other "free-from" claims aren't either. FARE notes that labels like "peanut free," "nut free" or "dairy free" aren't regulated or tied to specific allergen thresholds, and nothing requires those foods to be made on dedicated equipment or in a dedicated facility (FARE).
• "May contain" is voluntary. Statements like "may contain" or "made in a facility that also processes" are not required by law. The FDA says they must be truthful and not misleading, and shouldn't replace good manufacturing practices (FDA).

So a "free-from" claim is a promise from the brand, not a certification. What backs it up is how the product is made and tested.

What is cross-contact, and why does testing matter?

Cross-contact is the unintended introduction of a major allergen into a product (FDA), for example from shared equipment or a shared production line. It's why an ingredient list alone can't tell the whole story.

Warning labels don't fully close that gap. A review summarized by FARE found that processed foods without a precautionary label were almost as likely to contain detectable allergen as foods with one, and that many products carrying the warning had none (FARE). And after sesame joined the list, the FDA reported that some manufacturers began adding sesame on purpose and labeling it, rather than keeping it out (FDA).

That's why third-party testing, and results you can actually read, carry more weight than a badge. Look for which allergens are tested, how often, and against what limit.

How do common protein sources compare with the nine?

The source of the protein sets your starting point. This table covers protein sources, not brands, so always check the full label and allergen statement of the specific product.

Protein source	One of the nine?	What to know
Whey	Yes: milk	Made from milk. Isolate has less lactose than concentrate, but it's still a milk protein.
Casein	Yes: milk	The other main milk protein. Same allergen as whey.
Egg white	Yes: eggs	A dairy-free option, but not for anyone avoiding egg.
Soy	Yes: soybeans	A major allergen in its own right.
Pea	No	A legume, like peanut and soy. Pea allergy is documented, and some people with one legume allergy react to related legumes (Abu Risha et al., 2024).
Rice	No	Not one of the nine. Check for blends with other proteins.
Hemp	No	Not one of the nine. Check what it's blended with and the allergen statement.
Yeast protein	No	Isolated from baker's yeast. A true yeast allergy is rare, but the protein is yeast-derived, so check with your allergist if you have one.

Blends are where allergens often hide. A "vegan" or "dairy-free" powder can still contain soy, pea, nut butter powders, or a soy-derived lecithin, so read past the hero ingredient.

What should I look for on the label?

• The "Contains" statement. It names any of the nine that are ingredients. Read it on every flavor, since flavors can differ.
• The full ingredient list. Look for milk solids, whey, casein, egg, soy protein, soy lecithin, nut flours or butters, and seed blends.
• Any precautionary statement. "May contain" or "shared facility" tells you something about the process. Its absence doesn't guarantee there's no cross-contact.
• Testing details. Which allergens are tested, whether every batch is tested, and whether results are published.
• A gluten-free claim with a number. The FDA line is under 20 ppm. Some brands test lower and say so.
• A way to ask. A brand should be able to tell you how its product is made and tested.

Where does Spacemilk fit?

Spacemilk is the first protein made from baker's yeast. It's free from all 9 major allergens: dairy, soy, gluten, eggs, tree nuts, peanuts, fish, shellfish and sesame. Here's what sits behind that line:

• Testing. Every batch is tested for gluten, dairy, soy and peanuts. Those are the four we test for, and every result is published on our testing page, where you can match the lot code on your bag.
• Gluten. Every lot tests under 5 ppm gluten, against the FDA's 20 ppm line for gluten-free.
• Ingredients. Unflavored has one ingredient: yeast protein isolate. The flavored versions add sunflower lecithin (not soy lecithin), konjac fiber, sea salt, natural flavors, and Reb M, a sweetener fermented from rice, plus thaumatin. Chocolate adds organic cocoa.
• Vegan. No ingredients from animals.
• No live or active yeast. The protein is separated from the yeast during production.

Each serving gives you 20g of complete protein with a perfect protein quality score (PDCAAS 1.0) and 0g sugar, and it's formulated to be low in FODMAPs. Learn more in What is yeast protein?

The honest caveat: yeast isn't one of the nine, but it's still a protein source some people react to. A true baker's yeast allergy is rare, and if you have one, check with your allergist before using Spacemilk. More in Can you have yeast protein with a yeast allergy or candida? If you react to sunflower seeds, choose Unflavored or ask your allergist.

Who should check with an allergist

Talk to your allergist before trying a new protein powder if you've had anaphylaxis, you carry epinephrine, you manage several food allergies, or the powder is for a child. Your allergist knows your history and can tell you how cautious to be with any new food, including ours.

Never test a suspected allergy at home. The way allergists confirm or rule out a food allergy is an oral food challenge: the food is eaten slowly, in gradually increasing amounts, under medical supervision (AAAAI). That supervision is the point. If you've ever reacted to a food, don't recreate the test with a scoop in your kitchen.

If you have celiac disease, ask your care team what gluten threshold they want you to look for. Our results are on the testing page to bring to that conversation.

Frequently asked questions

What is the best allergen-free protein powder?

The one whose ingredients avoid your allergens and whose maker tests for cross-contact and publishes the results. For anyone avoiding several of the nine at once, a protein source that isn't one of them, such as yeast protein, is a simpler starting point than a blend.

Is there a protein powder without soy or dairy?

Yes. Rice, hemp, pea and yeast protein contain neither, as long as the blend doesn't add them. Spacemilk has no soy or dairy, and every batch is tested for both. For the dairy comparison, read Yeast protein vs whey.

Is Spacemilk nut-free?

Spacemilk is free from tree nuts and peanuts, and every batch is tested for peanuts. Tree nuts aren't one of the four allergens we test each batch for, so if you have a severe tree nut allergy, check with your allergist first.

Can I have pea protein with a peanut allergy?

Pea isn't one of the nine, but it's a legume, and some people with a peanut or legume allergy react to it. Ask your allergist. For how the two proteins compare, see Yeast protein vs pea protein.

Does "dairy-free" mean lactose-free and milk-protein-free?

It should, but the FDA doesn't define the term, so check the ingredient list and testing. If lactose is what bothers you, our guide to protein powder for a sensitive stomach covers what else to watch for.

Where can I find more answers?

Our FAQ covers ingredients, allergens and testing. Ready to try it? Shop Spacemilk Complete Protein.