By R.E. Hengsterman, MSN, RN
Table of contents
- Introduction
- What is multiple myeloma
- Early symptoms of multiple myeloma
- Genetic factors
- Precursor conditions
- Environmental and lifestyle risk factors
- Other potential risk factors
- FAQs
- Looking ahead: Research, hope, and progress
- A final word
- References
If you or someone you love has been diagnosed with multiple myeloma, one of the first questions that often comes up is: What causes multiple myeloma?
For many people, this question isn’t about biology, it’s about trying to understand something that suddenly feels very personal. Whether you're facing this diagnosis yourself or supporting someone you love, the need for answers is completely understandable. It's natural to feel anxious when learning about any kind of cancer, including multiple myeloma.
There is no single cause of this type of cancer, and in many cases, no clear answer as to why one person develops it and another does not.
However, learning about the risk factors and what may cause multiple myeloma can help you and your loved ones make sense of the diagnosis and make informed choices.
What is multiple myeloma?
If you are reading this, you may have just encountered this term for the first time. Here is a basic explanation of what it is.
Multiple myeloma is a cancer that forms in plasma cells, which are white blood cells that help fight infections.
When these cells become abnormal, they grow uncontrollably and crowd out healthy blood cells. Over time, this disrupts the immune system and can affect organs such as the kidneys (Blood Cancer United 2026).
Early symptoms of multiple myeloma
Noticing something different about your body can be unsettling, especially when you are not sure what it means.
The early symptoms of multiple myeloma can show up in different ways for different people. Some of the most commonly reported include (Blood Cancer United 2025):
- Bone pain, particularly in the back, hips, or chest
- Fatigue that doesn't improve with rest
- Frequent infections, due to a weakened immune system
- Kidney problems, which may show up as changes in urination or increased thirst
- Weakness or numbness in the legs
Many of these symptoms overlap with other common, less serious health issues. Experiencing them doesn't mean you have multiple myeloma, but they are worth talking about with your healthcare provider.
If you've noticed any of these symptoms and they persist or worsen, reaching out to your doctor is always the right move. Early conversations with your healthcare provider can bring clarity and, if needed, lead to earlier detection, which can make a meaningful difference in outcomes.
Genetic factors
If you or someone you love has just received a diagnosis, learning that cancer begins with genetic mutations can feel overwhelming. Understanding what that actually means may help.
Most cases of multiple myeloma begin with acquired genetic mutations in plasma cells, not inherited conditions (Blood Cancer United 2025).
These mutations disrupt how your cells:
- Grow and divide
- Repair damage
- Undergo normal cell death
Even when these mutations are identified, researchers cannot always determine exactly when or why they occur.
It's important to remember that most people likely did not inherit these mutations. They develop over time. While these changes are complex, they are common in many cancers and are a focus of ongoing research and treatment advances.
Precursor conditions
A diagnosis of a precursor condition can feel alarming, but understanding what it does and does not mean can make a real difference. Some people who develop multiple myeloma first experience earlier conditions called monoclonal gammopathy of undetermined significance (MGUS) and smoldering multiple myeloma (SMM).
Monoclonal gammopathy of undetermined significance
MGUS happens when abnormal plasma cells produce a protein known as M protein. Most people don't have any symptoms or organ damage, and it's usually found by chance on blood tests.
It's natural to worry if you've been diagnosed with MGUS. However, only about 1% of MGUS cases progress to multiple myeloma per year (Blood Cancer United 2024).
Smoldering multiple myeloma
SMM is a slightly more advanced precursor stage. Like MGUS, it's asymptomatic and is typically diagnosed when your blood or urine contains a certain amount of M protein.
For SMM, the risk of progressing to multiple myeloma is higher, with about a 10% likelihood per year for the first five years (Blood Cancer United 2024).
If you or a loved one has been diagnosed with MGUS or SMM, regular monitoring by a doctor is essential to closely look for signs of progression. For many people, regular monitoring brings reassurance—not just surveillance—because it means changes are caught early.
Environmental and lifestyle risk factors
Learning about risk factors can feel like a lot to take in, especially if some of them feel familiar. It helps to remember that a risk factor—or any number of risk factors—does not mean a person is guaranteed to have specific health outcomes.
Research from organizations such as the American Society of Hematology (ASH) and the National Comprehensive Cancer Network (NCCN) suggests that certain environmental and lifestyle factors may increase the chance of developing myeloma.
Age
As we get older, the likelihood of genetic mutations in our cells increases. If you're 50 or older, this may slightly raise the risk of developing multiple myeloma (Blood Cancer United 2025).
Sex
Males are diagnosed with multiple myeloma more often than females. While researchers continue to study whether hormonal differences are linked to this increase, it's important to know that this risk is just one potential factor (Blood Cancer United 2025).
Race and ethnicity
According to the NCCN, multiple myeloma is twice as common and twice as likely to lead to death in African Americans compared to white people living with myeloma (National Comprehensive Cancer Network 2026).
However, research shows that differences in outcomes are often driven by access to care. A real-world study by ASH found that when African American people with myeloma have similar access to care as white people, their survival outcomes are comparable (American Society of Hematology 2022).
Nutrition
Maintaining a healthy diet and weight can help keep your overall body and immune system strong. While this alone cannot prevent multiple myeloma, focusing on overall health and regular medical care can help reduce risk and support early detection (Blood Cancer United 2025).
You can learn more about diet, as well as metabolic and microbiome factors that affect immune function, blood cancer risk, and survival in our recent webinar: Dietary, Microbiome and Metabolism Evidence in Blood Cancers (Focus on Myeloma).
Chemical and radiation exposure
Exposure to certain chemicals or radiation may play a role in the development of multiple myeloma. These include:
- Pesticides
- Fertilizers
- Agent Orange
- Metals (cadmium, antimony, lead)
These substances can affect how cells repair damage over time, which may increase cancer risk—but researchers are still learning how and why this happens. If you work with these chemicals or have lived in environments with these exposures, let your provider know so they can monitor your health appropriately.
Other potential risk factors
If you have a parent or sibling with myeloma, you could have an increased risk of developing the disease.
Some studies have found that firefighters are at a 1.53 times higher risk for developing multiple types of cancer, including myeloma, than the general population (Blood Cancer United 2025). This is likely connected to the types of exposures firefighters encounter on the job. Modern homes and buildings contain synthetic and plastic materials that release carcinogens when they burn, including polycyclic aromatic hydrocarbons (PAHs).
Firefighters may also inhale or absorb through their skin other known carcinogens such as asbestos and diesel exhaust. Even with proper protective equipment, toxic chemicals can penetrate turnout gear and expose the skin to harmful substances.
The good news is that, even with these risk factors, many people never develop the disease and having one or more does not mean a diagnosis is inevitable. These are considered risk factors, not direct causes of multiple myeloma (Blood Cancer United 2025).
FAQs
What is the first sign of multiple myeloma?
There is no single first sign, and that can make it tricky to recognize early. Some people notice bone pain, unusual fatigue, or more frequent infections than normal. Others have no symptoms at all, and the first indication shows up in a routine blood test. If something feels off and has persisted for a while, it is always worth a conversation with your doctor (Blood Cancer United 2025).
How is the risk of multiple myeloma assessed?
Your doctor has straightforward tools to help figure out what is going on. A blood or urine test can detect abnormal proteins that may signal a problem, and imaging can check for any changes in your bones. In some cases a bone marrow biopsy is used for a closer look. The important thing to know is that these are well-established steps, and your care team has done this before. You do not have to figure it out on your own (Blood Cancer United 2025).
Looking ahead: Research, hope, and progress
Understanding why multiple myeloma develops is one of the most important questions in blood cancer research today, and it is one Blood Cancer United is actively working to answer.
We are helping drive research into both the genetic and environmental factors that affect how plasma cells become cancerous. That work matters because the more we understand about what causes myeloma, the better we can support the people living with it.
Advanced genetic testing now allows doctors to identify the specific mutations in a person's myeloma cells, which means healthcare providers can better predict how a condition may progress and choose treatments tailored to the individual. We are proud to support the kind of research that makes that level of personalized care possible.
Blood Cancer United supports advancing research, improving patient knowledge, and increasing access to care for people living with blood cancers. Our work not only funds scientific studies on the biology of blood cancers but also helps develop effective myeloma treatment options.
Learning will lead to better decision-making, which will lead to better outcomes. You can get involved by exploring and supporting research initiatives or donating to programs that advance new findings and improve patient care.
A final word
While uncertainty can be difficult, ongoing research continues to improve our understanding and treatment of this disease. If you're searching for answers, it’s important to remember:
- Multiple myeloma develops over time
- Most causes are not preventable or inherited
- Risk factors increase the likelihood but do not guarantee disease
You don’t have to navigate these questions alone—and we’re here to help you take the next step, whatever that looks like for you.
What matters most is working closely with your medical team, learning as much as you can about your disease, and getting the right kind of help.
And if you’d like to learn more about multiple myeloma, Blood Cancer United has resources for you.
References
- 2026. "Myeloma is a blood cancer." Blood Cancer United. https://bloodcancerunited.org/resources/blog/myeloma-blood-cancer
- 2025. “Myeloma: In Detail.” Blood Cancer United. https://bloodcancerunited.org/blood-cancer/myeloma.
- 2025. "Myeloma: The Basics." Leukemia & Lymphoma Society. https://llsorg.widen.net/view/pdf/ixujclnzks/en-booklet-myeloma-basics-ps49.pdf?t.download=true
- 2024. "Monoclonal Gammopathy of Undetermined Significance (MGUS) and Related Conditions." Leukemia & Lymphoma Society. https://llsorg.widen.net/view/pdf/js2rvyzm7y/en-booklet-monoclonal-gammopathy-undetermined-significance-fs40.pdf?t.download=true
- 2022. “Real-World Multiple Myeloma Risk Factors and…,” American Society of Hematology. https://ashpublications.org/blood/article/140/Supplement%201/5216/487514/Real-World-Multiple-Myeloma-Risk-Factors-and
- 2026. "Multiple Myeloma." National Comprehensive Cancer Network. https://www.nccn.org/patients/guidelines/content/PDF/myeloma-patient.pdf
