What Does Blood Smell Like? Its Causes and When It's an Emergency

The Distinctive Smell of Blood

Blood has a very unique and distinctive smell that is unfamiliar to most people. Unless you work in healthcare, law enforcement, or some other field that exposes you to blood regularly, smelling blood is not very common.

So what does blood smell like exactly? The smell is not easy to describe, but it has some similarities to the smell of raw meat. There is an irony, coppery scent that comes from the iron in blood. The smell can range from slightly sweet to more metallic and salty depending on the amount of blood present.

Where the Smell Comes From

The source of blood's odor comes from the components that make up this vital fluid. Blood consists of plasma, platelets, white blood cells, and red blood cells. The red blood cells contain hemoglobin, an iron-rich protein that carries oxygen throughout your body. It's the iron from the breakdown of hemoglobin that produces the distinctive bloody smell.

When blood exits the body, the hemoglobin starts to break down. This releases volatile sulfur-containing compounds that disperse into the air and give off the telltale scent. The more blood present, the more intense and noticeable the odor becomes.

Comparing Blood's Smell to Other Odors

As mentioned, blood has an irony, coppery scent in the same vein as a raw steak or metal coins. Some also describe it as smelling sweet or salty. The odor is very distinct once you've smelled it before. It does not really compare to other bodily odors.

For example, sweat and urine have ammonia-like smells from urea. Feces smells bad due to bacteria and digested food compounds. Neither compares to the uniqueness of the smell of hemoglobin breaking down outside of the body.

Why Smelling Blood Occurs

There are only certain situations that will cause you to smell blood. The main instances include:

• Getting a nosebleed
• Having blood drawn
• Cutting yourself and bleeding
• Being around someone else who is bleeding
• Working in healthcare, law enforcement, veterinary care, or other fields with blood exposure risk

If you suddenly notice the smell of blood without any apparent reason, it could signal an issue. Smelling blood without a source could indicate:

• Nose, sinus, or mouth inflammation or irritation
• A nutrient deficiency like iron or vitamin B12 deficiency
• A head injury causing nosebleeds into the nasal cavity

See your doctor if you smell blood persistently with no known cause.

Why Some People Smell Blood When None is Present

In some cases, people think they smell blood when there is no actual source of blood present. This phantom odor perception is called dysosmia or phantosmia. It can occur for a few different reasons:

• Chronic sinus infections
• Growths or tumors in the nasal cavity
• Head injuries
• Alzheimer's disease or dementia
• Parkinson's disease
• Hypertension

Issues with the central nervous system and certain neurological disorders seem to be common triggers for sensing smells that are not there. If no medical cause is found, anxiety and stress can also make some people perceive odors like blood that don't exist.

When Phantosmia Requires Evaluation

In most cases, phantosmia resolves on its own. But if the false smell of blood persists for weeks or happens frequently, you should make an appointment with your doctor. Smelling odors others can't detect could signal something more serious like:

• A tumor
• Nerve damage
• Early Parkinson's disease
• Impending seizure
• Stroke risk

Brief smells triggered by stress are probably nothing to worry about. But unusual phantom odors, especially those that are foul or burn-like, do require medical assessment when they linger or occur often.

The Smell of Blood After Injury or Surgery

It's very common to smell blood after you have had any blood loss caused by injury, surgery, nosebleeds, etc. The scent is strongest right after the bleeding incident but can linger for 24-48 hours.

Why Post-Injury Blood Smells Different

Blood has a different odor when it exits the body versus inside the body or when stored. This is because changes happen when blood makes contact with air and the environment.

Oxygen, temperature changes, pH changes, and dehydration initiate chemical shifts in blood components after leaving the circulatory system. This alters the smell from what you may associate with tests that use stored blood samples.

Coping with Blood's Smell After Procedures

It's perfectly normal to smell blood for the day or so after any blood loss, including:

• Nosebleeds
• Menstruation
• Giving blood
• Having blood drawn
• Getting stitches
• Undergoing surgery

Use fragrance-free wipes or gentle soap and water to keep the area clean where bleeding occurred. This can help diminish leftover bloody odor on the skin's surface. Avoid strong-smelling products, perfumes, or heavily fragranced body washes in the direct area until bleeding fully stops.

The smell should fade as the blood loss stops and any internal bleeding resolves. See a doctor if you smell blood longer than 2 days after any significant bleeding incident.

When the Smell of Blood Signals an Emergency

While smelling blood can be unpleasant, it is rarely an emergency. The exception is smelling blood along with these alarming symptoms:

• Coughing up blood
• Vomiting blood
• Blood in urine or stool
• Heavy vaginal bleeding between periods
• Severe head injury
• Suddenly collapsing or losing consciousness

These signs paired with a blood scent mean you could have internal bleeding or a severely damaged blood vessel. It requires emergency care to prevent deadly blood loss or choking on blood vomit.

What to Do for Signs of Internal Bleeding

Take action right away if you or someone around you notices the smell of blood along with any severe symptoms. Call emergency services or get the person to the ER or urgent care clinic without delay. With rapid blood or internal organ damage, minutes matter.

While waiting for help, have the person lie on their left side with their neck and head positioned slightly lower than their torso if possible. This prevents choking if they vomit blood. Apply direct pressure if you locate external bleeding. But do not give them anything to eat or drink until evaluated.

Preventing Blood Odors in Everyday Life

Aside from donating blood or working jobs exposed to blood, most people want to avoid smelling it! Here is how to prevent the smell of blood in day-to-day living:

• Practice safe cutting skills - Go slowly, use sharp knives, and always cut away from fingers to avoid lacerations that lead to bleeding and the bloody odor.
• Handle raw meat carefully - Rinse all meat before cooking, avoid contact between raw meat and other foods, and disinfect counters/cutting boards after to prevent illness and contamination with blood-like meat juices.
• Wear protective gear for hazardous activities - Use appropriate gloves, pads, helmets, masks, and goggles during sports, construction work, yardwork, hiking, cleaning, and other activities with injury risks.
• Treat nosebleeds safely - Stop activity immediately if you get a nosebleed. Sit leaning forward while applying firm, consistent nose pressure until it stops. See a doctor if you get frequent or heavy nosebleeds.
• Practice safe sex - Sexual activity can cause bleeding or introduce blood. Using barriers like condoms reduces exposure to blood and body fluids.

While the smell of blood cannot always be avoided, smart safety practices can lower everyday risks of coming in contact with bloody odors.

What to Do If Blood Odor Lingers

Occasionally noticing the smell of your blood is no cause for concern. But if you smell blood persistently or notice a consistent bloody odor coming from someone else, seek medical guidance. Lingering blood scent could mean:

• An infection
• Remaining blood traces from past nosebleeds, dental procedures, etc.
• Nutrient deficiency
• Undiagnosed internal issue

Document when you notice the smell, how often, for how long, and if anything makes it better or worse. This can help your provider pinpoint the likely cause so suitable treatment can be offered.

Disclaimer: This article is for informational purposes only and does not constitute medical advice. Always consult with a healthcare professional before starting any new treatment regimen.