“No added hormones” on a food label means the animal was raised without receiving any supplemental hormones beyond what its body naturally produces. The claim appears most often on beef and dairy products, where hormone use is legal and common in conventional farming. On pork and poultry, the label is more complicated, because federal regulations already restrict hormone use in those animals.
How Hormones Are Used in Beef Production
Beef cattle in conventional operations routinely receive hormone implants to promote faster growth and more efficient weight gain. The approved hormones include three naturally occurring ones (estradiol, progesterone, and testosterone) and synthetic versions like trenbolone acetate and zeranol. These are typically delivered as small pellets implanted under the skin of the ear, a location chosen specifically so the implant site is discarded at slaughter and never enters the food supply. One synthetic progestin is instead mixed directly into feed at small daily doses.
The implants work over periods of 90 to 400 days depending on the formulation. A single steer might receive one or more implants during its life to boost weight gain by roughly 10 to 20 percent while using less feed. When a product carries the “no added hormones” or “no hormones administered” label, the producer is claiming none of these implants or feed additives were used at any point during the animal’s life.
What the USDA Requires for the Claim
The USDA’s Food Safety and Inspection Service (FSIS) must approve all label claims before they appear on meat products. To get a “no hormones administered” claim approved, a producer needs to submit detailed documentation: a written description of how the animals were raised, an explanation of the controls ensuring no hormones were given from birth to slaughter, a product tracing and segregation plan showing treated and untreated animals were kept separate through packaging and distribution, and a protocol for handling any animals that fall out of compliance.
If a third-party organization certifies the claim, a current copy of that certificate must also be provided. The USDA’s Agricultural Marketing Service offers a Process Verified Program where auditors conduct desk reviews and on-site inspections of a company’s quality systems using international standardization frameworks. This is voluntary, though. Not every producer with a “no added hormones” label goes through this level of independent verification. Some rely on their own documentation and the FSIS label approval process.
The Pork and Poultry Catch
For years, FSIS required pork and poultry labels carrying “no hormones” claims to include a disclaimer stating that federal regulations already prohibit hormone use in those animals. The logic was straightforward: if hormones aren’t allowed in the first place, claiming their absence could mislead consumers into thinking the product was special when it wasn’t.
The situation with pork shifted in 2019. The FDA does approve certain hormones for use in swine during specific stages like gestation, so the old blanket disclaimer (“Federal Regulations prohibit the use of hormones in pork”) was no longer accurate. FSIS updated its guidance: pork products can now carry a “no hormones” claim without a disclaimer, but the producer must submit documentation proving the claim is true. For poultry, hormones remain prohibited across the board, so any “no added hormones” label on chicken or turkey is technically describing the industry standard rather than a meaningful distinction.
How It Differs From USDA Organic
A “no added hormones” label addresses one thing: whether the animal received supplemental hormones. It says nothing about antibiotics, feed quality, living conditions, or pesticide exposure. USDA Organic certification, by contrast, prohibits added hormones as part of a much broader set of requirements that also cover organic feed, outdoor access, no routine antibiotics, and restrictions on synthetic chemicals. Every organic product is hormone-free, but not every hormone-free product is organic.
This matters for pricing. Products labeled only “no added hormones” are typically less expensive than organic because the producer hasn’t met the full suite of organic standards. If hormones are your primary concern, the simpler label gives you what you’re looking for at a lower cost.
How Much Hormone Is Actually in Meat
The difference in hormone levels between treated and untreated beef is real but small in absolute terms. Muscle tissue from untreated cattle contains an average of about 6.4 picograms of estradiol per gram. Treated cattle have roughly 3.7 times more, bringing that to about 24 picograms per gram. For context, a picogram is one trillionth of a gram.
Scaled up to a full day’s worth of beef consumption (about 500 grams of mixed edible tissues, a generous estimate), the theoretical maximum intake of estradiol is 4.3 nanograms from untreated cattle and 20 nanograms from treated cattle. That 20-nanogram figure is still a tiny fraction of what the human body produces daily. A prepubertal boy produces around 40,000 to 60,000 nanograms of estrogen per day, and adult women produce several hundred thousand nanograms depending on their cycle phase.
A lab study comparing estrogenic activity across common foods found that a quarter-pound beef burger from hormone-implanted cattle had roughly the same estrogenic activity as a burger from untreated cattle: about 384 versus 389 picogram estradiol equivalents per serving. A tofu burger, by comparison, contained about 1,020,000 picogram estradiol equivalents, roughly 2,600 times more estrogenic activity than either beef burger. The plant estrogens in soy work through different biological pathways than animal estrogens, but the comparison illustrates just how low the estrogenic activity in beef is relative to other everyday foods.
Why Ingested Hormones Have Low Impact
The hormones present in meat are largely broken down during digestion. Estradiol is a protein that gets degraded by digestive enzymes in the gastrointestinal tract and is not absorbed intact. The fragments that remain have no biological activity. Progesterone is poorly absorbed orally, with less than 10% bioavailability after passing through the gut and liver. Testosterone fares even worse, with only about 3.6% of an oral dose surviving digestion and liver metabolism.
The Joint FAO/WHO Expert Committee on Food Additives concluded that the amount of estradiol a person would ingest from eating treated beef is incapable of exerting hormonal effects in humans. Even if bovine growth hormone (used in dairy, not beef) were somehow injected directly into a person, growth hormones from cattle have no biological activity in the human body because of species-specific differences in how these proteins work.
Dairy and the rBST Label
In dairy, the relevant hormone is recombinant bovine somatotropin (rBST), a synthetic version of a growth hormone cows naturally produce. The FDA approved it in 1993 for increasing milk production. Milk from treated cows carries a zero-day withdrawal period, meaning it’s considered safe for consumption immediately after treatment.
Many dairy brands now label their milk as “from cows not treated with rBST.” This is a voluntary marketing claim, not a safety distinction recognized by the FDA. The agency’s position is that milk from treated and untreated cows is nutritionally and chemically indistinguishable. The bovine growth hormone in milk is a large protein that gets broken down during digestion like any other dietary protein, and even intact, it has no activity in the human body.
Consumer preference has driven most major dairy processors to drop rBST regardless. If you see “no artificial hormones” or “rBST-free” on milk, it reflects a production choice rather than a measurable difference in the milk itself.