Blood spots in eggs are safe to eat. They’re caused by a minor accident during egg formation, not by disease, contamination, or fertilization. The USDA confirms that small blood or meat spots are rare but normal occurrences that pose no impact on egg safety or quality.
What Causes Blood Spots in Eggs
When a hen’s ovary releases a yolk, the sac surrounding it ruptures along a specific line that normally has no blood vessels. If the rupture happens slightly off that line, a tiny blood vessel can leak a small amount of blood that gets sealed into the egg as it forms. Less commonly, a blood vessel in the oviduct (the tube the egg travels through) can break during the same process.
The result is that small red or dark spot you see on the yolk when you crack the egg open. It looks alarming, but it’s essentially a minor bruise from the egg-making process. It has nothing to do with the hen being sick or the egg going bad.
Blood Spots Don’t Mean the Egg Is Fertilized
One of the most common misunderstandings is that a blood spot means the egg contains a developing chick. It doesn’t. Commercial eggs are infertile because hens in egg-laying operations aren’t housed with roosters. Even in backyard flocks where a rooster is present, a blood spot is still just a ruptured blood vessel, not evidence of an embryo. Fertilized eggs that have started developing look distinctly different, with visible veins branching outward rather than a single isolated spot.
No Extra Bacteria Risk
Blood spots don’t increase the risk of salmonella or other foodborne illness. The bacteria that occasionally contaminate eggs enter through other routes, either passed from an infected hen before the shell forms or picked up through cracks in the shell afterward. A blood spot is internal to the egg’s normal formation and doesn’t create any additional pathway for contamination. Standard safe-cooking practices (cooking eggs until both the white and yolk are firm) protect you regardless of whether a spot is present.
Why You Rarely See Them in Store-Bought Eggs
If blood spots are a normal occurrence, you might wonder why you almost never find one in a carton from the grocery store. The answer is candling, a quality-control step where eggs pass over bright lights on a conveyor belt. The light shines through the shell and reveals internal defects like cracks, blood spots, dirt, and misshapen yolks. In most processing plants, workers inspect the illuminated eggs and remove any with visible flaws by hand. Some facilities use automated detection systems as well.
This process catches most blood spots before they reach consumers, but it isn’t perfect. White-shelled eggs are easier to screen because light passes through them more clearly. Brown eggs, with their thicker and darker shells, make spots harder to detect. That’s why you’re more likely to find a blood spot in a brown egg than a white one, even though both types produce them at similar rates.
How to Handle a Blood Spot
You have two options, and both are fine. You can cook and eat the egg as-is, spot included. The blood spot won’t change the taste, texture, or nutritional value of the egg in any noticeable way. If the appearance bothers you, use the tip of a knife to scrape the spot off the yolk before cooking. It lifts off easily. The same approach works for “meat spots,” which are small brown or tan bits of tissue that occasionally appear in eggs through a similar process.
There’s no need to throw the egg away. The only reasons to discard an egg are the usual ones: a foul smell, an unusual color throughout the white or yolk, or a slimy texture, all signs of actual spoilage that have nothing to do with a blood spot.