Raw Milk
Milk from cows, goats, sheep or other animals that has not been pasteurized, a heat treatment that kills harmful germs.
Last revised
Key takeaways
- What pasteurization does: heats milk to kill harmful germs without significantly changing its nutritional value
- Interstate sale for drinking: banned by federal law; state laws on in-state sale vary
- Most useful single change: Look for the word "pasteurized" on milk, cheese and other dairy labels.
- Commonest mistake: Raw milk, cheese or yogurt during pregnancy or for babies and young children.
- See a doctor if any of the signs under "When to get help" below apply to you.
Why it matters
Raw milk and products made from it can carry Listeria, Salmonella, E. coli, Campylobacter and Brucella, and bird flu virus has been found in raw milk from infected dairy cows.
The numbers, in one place
| Measure | Figure |
|---|---|
| What pasteurization does | heats milk to kill harmful germs without significantly changing its nutritional value |
| Interstate sale for drinking | banned by federal law; state laws on in-state sale vary |
| Germs it can carry | Listeria, Salmonella, E. coli, Campylobacter, Brucella and H5N1 bird flu virus |
| Highest-risk groups | pregnant people, babies and young children, older adults, and people with weakened immune systems |
| Products to check | milk, soft cheese such as queso fresco, yogurt, ice cream |
What helps
- Look for the word "pasteurized" on milk, cheese and other dairy labels
- Choose pasteurized milk and cheese for children and during pregnancy
- Refrigerate milk at 40°F (4°C) or below and use it by the date on the label
- Ask about pasteurization when buying dairy at farmers markets or farm stands
What to avoid
- Raw milk, cheese or yogurt during pregnancy or for babies and young children
- Assuming milk from a clean, local or organic farm is free of germs
- Feeding raw milk to pets, which can also become ill
In depth
Milk straight from an animal can pick up germs in several ways: from the animal's udder or blood if it is infected, from manure on the skin and equipment, and from the environment during milking and storage. Even farms with careful hygiene cannot fully prevent this, because healthy-looking animals can carry harmful bacteria. Pasteurization, which heats milk to a set temperature for a set time, was introduced in the US in the early 1900s and is credited with a large drop in diseases once commonly spread through milk.
Some people choose raw milk because they believe it is more natural, tastes better, or offers extra nutrients, enzymes or probiotics. According to the FDA and CDC, pasteurization does not significantly reduce milk's nutritional value, and claims that raw milk treats or prevents conditions such as allergies or lactose intolerance are not supported by evidence. Meanwhile, the risks are well documented: raw milk causes a disproportionate share of dairy-linked outbreaks relative to how little of it is consumed.
Since 2024, highly pathogenic H5N1 bird flu has been found in dairy cattle in the US and in raw milk from infected herds. Pasteurization inactivates the virus, and federal agencies have advised against consuming raw milk and raw-milk products because of this added risk. Laws on raw milk differ widely between states, from outright bans on retail sale to farm-only or retail sale, but federal law bans selling raw milk for drinking across state lines.
Signs and symptoms
- Diarrhea, sometimes bloody, with stomach cramps and vomiting
- Fever, chills and body aches
- Fever, muscle aches and fatigue in pregnancy, which may signal Listeria
- Recurring fevers, sweats and joint pain over weeks, which may signal brucellosis
- Red, irritated eyes or flu-like symptoms after contact with raw milk from infected herds
- Weakness or tingling in the legs that spreads upward, a rare complication after Campylobacter
Causes and risk factors
- Bacteria from an infected udder or from the animal's bloodstream
- Manure contamination during milking
- Unclean equipment, tanks and bottling
- Warm storage that lets bacteria multiply
- Infected herds carrying H5N1 bird flu
- Soft cheeses and other products made from unpasteurized milk
How it is checked
Tell your doctor that you drank raw milk or ate products made from it, because this changes what they look for. Stool tests can identify Campylobacter, Salmonella and E. coli. Listeria and Brucella are usually found through blood tests. Your doctor may also check kidney function if you have bloody diarrhea, because some E. coli infections can damage the kidneys.
If you have flu-like symptoms or eye irritation after contact with raw milk that might come from infected cattle, your doctor may test for influenza and contact the health department, which can arrange specific testing for H5N1. These cases are monitored closely by public health authorities.
Related topics
- The Evidence on West Nile Virus and Mosquitoes, Without the Hype (Infectious Diseases)
- Gut Health and Immunity: What the Evidence Actually Says (Immunity)
- The Evidence on Vegetarian and Vegan Diets, Without the Hype (Healthy Recipes)
- Food Allergy: What the Evidence Actually Says (Allergies)
Where to go next
- Raw Milk: The Questions People Actually Ask
- The Short Guide to Raw Milk
- Food Safety: The Complete Guide
- Eggs and Salmonella: What Published Guidance Supports
- Listeria in Pregnancy: What Published Guidance Supports
When to get help
See your doctor if you develop vomiting, diarrhea, fever, muscle aches or red, irritated eyes after drinking raw milk, and tell them what you drank. Call 911 for bloody diarrhea with little or no urine, a stiff neck with fever, confusion or a seizure.
Where this comes from
How this page was put together
Every figure, recommendation and warning above is taken from the guidance named in Where this comes from. Nothing on this page is inferred, summarized or generalized beyond what those bodies publish: where they give a number, it is their number, and where they are silent, so are we. Pages are rebuilt whenever the underlying record changes. Sign-off by a named clinician, where it has happened, is shown at the top of the page along with the date.
Medical disclaimer
This article is general information, not medical advice. It cannot account for your own history, medication or circumstances. Always speak to your doctor, pharmacist or another qualified health professional before making changes that affect your treatment, and never delay seeking medical advice because of something you have read here. In an emergency, call 911.