Can Chickens Eat Cheese? Better Not: The Salt and Fat Math

Short answer: better not. If cheese does go out to the run, a crumble about the size of your thumbnail, shared around, is plenty. The salty ones (feta and parmesan) are the worst picks. And going by USDA’s numbers, plain cottage cheese is the least bad.

None of the poultry sources I read gives a safe amount of cheese for a hen. What they do publish is a short set of rules for kitchen scraps, and most cheese breaks two of them. So I pulled each common cheese’s numbers out of USDA’s food database and did the arithmetic against those rules. The math is below, said plainly as mine, with every source named at the bottom.

If you’re standing at the counter with some other scrap in your hand, the free Can Chickens Eat It? checker tells you yes or no and where that answer comes from. It also works out how much your flock can have today.

What the Poultry People Actually Say

Here’s what the extension services and the vets say about scraps, in their own words.

• Colorado State University Extension names leafy greens and vegetable peelings as good scraps, and bread products too. Then it adds: “Make sure they are not salty or have citrus or are moldy”. It caps treats at 10 percent of a hen’s daily diet.
• UC Davis (its vet school and UC Cooperative Extension, in the guide Feeding your Flock) says it straight: “Chickens don’t require high amounts of fat, so avoid fatty foods”.
• The Merck Veterinary Manual, in its backyard poultry chapter, goes further. Fat scraps “should also be avoided, because they promote the development of fatty liver and acute death from liver rupture”.

Most cheese is salty and fatty at once. That’s two strikes, from two different rule books.

There’s a third thing, and it’s the milk sugar. Poultry scientists at NC State put it flatly in a 2003 paper in The Journal of Nutrition: “Chickens do not possess the necessary enzymes to efficiently hydrolyze lactose into glucose and galactose”. In plain words, a hen can’t break down milk sugar well. That study measured gut enzymes. It didn’t feed anybody’s hens cheese, and I didn’t find a study that did. So I won’t tell you what a crumble does to her gut. I’ll only tell you she isn’t built for dairy.

And again, not one of them gives a safe amount. Not the extension services, not Merck. So if a page tells you “a tablespoon twice a week,” somebody made that number up.

The Salt and Fat Math, Cheese by Cheese

“Salty” is vague, so I wanted a number. Here’s how I got one.

The University of Maine Extension says sodium goes into chicken feed at about 0.15 percent. Alabama Extension puts a laying hen at 100 to 150 grams of feed a day. So her feed alone hands her 150 to 225 milligrams of sodium. Colorado State’s 10 percent cap makes her whole treat allowance 10 to 15 grams.

Now fill that allowance with one food and see how much sodium it adds on top of her feed. These are USDA FoodData Central’s figures per 100 grams. The percentages are my math (and they come out the same for a small hen or a big one, since both sides scale with what she eats).

• Parmesan, hard: 1,180 mg. About 79 percent on top of her feed’s sodium.
• Feta: 1,139 mg. About 76 percent.
• Sharp cheddar: 644 mg. About 43 percent.
• Plain white bread: 490 mg. About 33 percent. Yes, bread.
• Whole-milk mozzarella: 486 mg. About 32 percent.
• Cottage cheese: 315 mg. About 21 percent.
• Swiss: 187 mg. About 12 percent.

That one surprised me. Swiss is less salty than the bread Colorado State calls a fine scrap, and so is cottage cheese. So salt alone doesn’t sink every cheese. It sinks feta and parmesan, and it makes cheddar a poor pick.

Fat is where cheese loses across the board. USDA has white bread at 3.33 grams of fat per 100 grams. Against that:

• Cheddar: 33.82 grams, about 10 times the bread.
• Swiss: 31 grams, about 9 times.
• Parmesan: 25 grams, about 7.5 times.
• Mozzarella and feta: about 22 grams each, around 6.5 times.
• Cottage cheese: 4.3 grams, about 1.3 times.

So Swiss wins on salt and loses on fat. Cottage cheese is the only one that comes in close to bread on both. That’s my reading of USDA’s numbers, not a rule anybody published.

To be fair to fat, it isn’t poison. University of Maryland Extension’s winter guide says suet cakes with birdseed, fed sparingly, can add fat to a flock’s diet, inside the same 10 percent. But that’s a winter energy treat the guide picked on purpose. A slice of cheddar off the cutting board is a different thing, and UC Davis and Merck both say to keep fatty scraps away from hens.

The Calcium Argument Runs Backwards

The usual case for cheese is that it’s full of calcium, and laying hens need calcium for their shells. Both halves of that are true. The conclusion still isn’t.

Merck says a typical egg takes about 2 grams of calcium from her diet, and that laying birds need a diet of 3.5 to 6 percent calcium. Alabama’s table for a layer diet says 3 to 4 percent. Either way, her layer feed is the calcium-rich thing in her day.

Run cheddar against Alabama’s figure. Cheddar has 711 milligrams of calcium per 100 grams, or about 0.7 percent. Layer feed at 3 to 4 percent has roughly four to six times that, gram for gram. Even parmesan, the richest cheese on my list at 1,180 milligrams, carries only 30 to 40 percent of layer feed’s calcium. Cottage cheese has 83 milligrams, so feed beats it 36 to 48 times over.

Here’s the part that matters. Treats don’t land on top of her feed. They take its place, because she fills up. Alabama says a complete feed is built to be the sole source of her nutrients, and that with too many treats her laying is likely to suffer. So every gram of cheese she eats instead of feed means less calcium that day, not more.

Protein is the one place cheese looks good on paper. Alabama wants layer feed at 16 percent protein or more, and cheddar is about 24 percent. But her feed already covers her protein, and UC Davis warns that scraps crowding out the balanced diet can cause nutritional disorders. A hen that’s laying well doesn’t have a gap for cheese to fill. If you want to know how much feed your flock really goes through, the chicken feed calculator works it out from Alabama’s figures.

Why Salt Matters More When the Water Freezes

Here’s where I’ll drop the dry tone, because this is the part that can hurt a bird.

Merck’s page on salt poisoning says animals can handle a lot of salt in their diet as long as they have fresh water the whole time. Trouble starts when the water stops. Among the things that cut it off, Merck names broken waterers and frozen water sources. And it says chickens are susceptible to salt toxicosis when their water intake is restricted.

Winter is exactly when that happens. Maryland Extension’s winter guide says water that’s frozen over isn’t available to the birds, and they can’t break through the ice to get to it. It tells you to check the water several times a day. Hens drink less in winter, it says, but they still need water to survive.

So a frozen waterer on a January morning is the worst time for salty scraps. Thaw the water first. Feed the leftovers later, or not at all. (Not sure how cold is too cold for your coop? Our cold weather tool quotes the same Maryland guide.)

Merck lists these signs of salt poisoning in poultry:

• increased thirst
• labored breathing, with fluid coming from the beak
• weakness or diarrhea
• leg paralysis

If you see that after your flock got into something salty, get fresh water in front of them and call a vet who sees poultry. Don’t work it out from a web page, this one included. We aren’t vets. Colorado State says every flock owner should have a vet lined up who can treat chickens, and that’s good advice before you ever need one.

Cheese Bread and Pizza Are Worse, Not Better

This page used to be three pages. The old cheese bread and cheese pizza pages said both were fine in moderation. They’re gone now and they point here, because the answer is the same, only worse.

• Cheese bread has 750 mg of sodium per 100 grams in USDA’s data. On a full treat allowance that’s about 50 percent on top of her feed’s sodium. It carries about six times the fat of white bread, too.
• Cheese pizza (frozen, then baked) has 447 mg of sodium and 12.3 grams of fat. That’s a little less salt than plain bread, but nearly four times the fat. If the sauce has onion in it, that’s a food Colorado State says to avoid, and our onions and tomatoes page goes through why.
• Plain crust with nothing on it is bread, and bread is a scrap Colorado State names as fine. Tear the crust off and bin the rest.

The slice somebody left on the patio table overnight goes in the trash, not the run. Colorado State says no moldy scraps at all, and UC Davis says no rotten food. A slice that’s been sitting out long enough to grow something fails both.

If Your Kid Wants to Hand Over a Crumble

I’m not going to pretend a crumble of cottage cheese will hurt a healthy hen who has water. None of my sources shows that, and I won’t invent it. If somebody in the house wants to hand a bit to the friendliest hen, here’s how I’d keep it sane.

• Pick the least bad cheese. By USDA’s numbers that’s plain cottage cheese. Mozzarella comes next. Leave the feta and parmesan in the fridge.
• A crumble, not a slice. Thumbnail size, shared across the flock. It still counts toward the 10 percent. A 1-ounce slice of cheddar weighs 28 grams, which is about two to nearly three hens’ whole treat allowance for the day.
• Nothing mixed in. No onion, and no sauce.
• Not on a frozen-water morning. Get the waterer thawed first.
• Gone in minutes. Colorado State says not to put out more than the flock can eat in 5 to 10 minutes, so nothing’s left to draw nuisance animals. A crumble won’t last that long anyway.

What to Give the Flock Instead

The treats that don’t come with any of this doubt are the boring ones. Colorado State names leafy greens and vegetable peelings as good scraps, plus bread products. It says to be cautious with potato peelings, and to skip avocado skins and pits.

UC Davis has its own list of things to keep out of the run, and it’s worth taping inside the lid of your feed bin:

• avocado
• raw beans
• chocolate
• the green parts of potatoes
• leaves from tomato, rhubarb, pepper, potato, eggplant or nightshade plants
• alcohol or tobacco

Whatever you hand over comes out of the same 10 percent. Weigh a day’s treats for your flock once on a kitchen scale. At 10 to 15 grams a hen, six hens get 60 to 90 grams between them. That’s not much, and it goes fast. The checker does that sum for any flock size, and our watermelon page shows how little of a treat that allowance really holds.

Updated October 2026: rewritten from the sources below and checked again line by line. The old version’s lines about one keeper’s own twelve hens and coop are gone. So is its list of treats that no source here names (pumpkin and winter squash with their seeds, cucumber and melon, berries, cooked rice or oats, and mealworms). It also said the hard, aged cheeses are the salty ones, but Swiss, an aged cheese, has less sodium than white bread, so each cheese now gets its own number.

Sources

• Colorado State University Extension: Raising Poultry the Organic Way: Disease Control and Feeding (Howard Enos, December 2019, reviewed August 2025)
• UC Cooperative Extension and UC Davis School of Veterinary Medicine: Feeding your Flock (Dr. Maurice Pitesky and Dr. Nancy Reimers)
• University of Maine Cooperative Extension: Salt is an Important Nutrient for Poultry
• Alabama Cooperative Extension System: Feeding the Laying Hen (ANR-2913; Pacheco, Gulizia and Downs, August 2022)
• Merck Veterinary Manual: Management of Backyard Poultry (Yuko Sato, DVM; reviewed November 2024)
• Merck Veterinary Manual: Salt Toxicosis in Animals (Larry J. Thompson, DVM, PhD; reviewed May 2022)
• University of Maryland Extension: Winter Weather and Small Flocks: What You Need to Know (FS-1133, June 2020)
• Mozdziak, Pophal, Borwornpinyo and Petitte: Transgenic Chickens Expressing Beta-Galactosidase Hydrolyze Lactose in the Intestine (The Journal of Nutrition, 2003; NC State Department of Poultry Science)
• USDA FoodData Central (SR Legacy, per 100 g): sharp cheddar (170899), whole-milk mozzarella (170845), creamed cottage cheese (172179), feta (173420), hard parmesan (170848), Swiss (171251), cheese bread (167944), frozen cheese pizza, cooked (170317), and white bread (174924). The percentages and ratios above are my arithmetic from these figures.

Sources checked October 26, 2026. We aren’t vets. If a bird goes off her food or sits fluffed up after getting into something, call a vet who sees poultry.

Related read: How to Raise Chickens for Eggs — Instant PDF download. Secure checkout by Stripe