Scientists used advanced genetic analysis to explore whether vitamin B12 deficiency and abnormal red blood cells might increase the risk of prostate cancer. They studied genetic data from thousands of people and found modest connections between these blood conditions and prostate cancer risk. The research identified two specific genes that might explain how these blood problems could affect prostate cancer development. While the findings are interesting, the actual risk increase is small, and more research is needed before doctors change how they screen or treat patients.

The Quick Take

  • What they studied: Whether vitamin B12 deficiency and red blood cell abnormalities (measured by something called RDW) could cause prostate cancer, and which genes might be involved
  • Who participated: This study didn’t involve individual people directly. Instead, researchers analyzed genetic information from hundreds of thousands of people collected in previous large studies to look for patterns
  • Key finding: People with genetic risk for B12 deficiency had about 5% higher prostate cancer risk, and those with higher RDW had about 10% higher risk. These increases are small but consistent across multiple analyses
  • What it means for you: If you have B12 deficiency or abnormal red blood cells, your prostate cancer risk may be slightly elevated, but it’s still relatively low. This doesn’t mean you need new screening or treatments right now, but it’s worth discussing with your doctor, especially if you have other risk factors

The Research Details

This study used a sophisticated genetic method called Mendelian randomization, which is like a detective tool for finding cause-and-effect relationships in genetics. Instead of following people over time, researchers analyzed genetic variations from large databases to see if B12 deficiency and red blood cell problems actually cause prostate cancer, rather than just being associated with it.

The researchers also did lab experiments where they starved cells of B12 to see what happened to them. They looked at whether the cells showed signs of damage, changed how they divided, or changed their characteristics in ways that might lead to cancer.

Finally, they identified specific genes that might be the bridge connecting these blood problems to prostate cancer risk, using multiple statistical techniques to confirm their findings.

This approach is important because it helps separate real cause-and-effect from mere coincidence. Regular studies can show that two things happen together, but they can’t always prove one causes the other. By using genetic information, researchers can get closer to understanding true causal relationships. The lab experiments add extra evidence by showing biological mechanisms that could explain the connection.

Strengths: The study used large genetic databases representing hundreds of thousands of people, making the findings more reliable than small studies. Multiple statistical tests confirmed the results were robust. Lab experiments provided biological evidence. Limitations: The actual risk increases are modest (5-10%), which means they’re real but small. The study is based on genetic associations, not direct observation of people. The genes identified need further study to understand exactly how they work.

What the Results Show

The research found that people with genetic predisposition to B12 deficiency had about 5.4% higher risk of prostate cancer. People with higher red blood cell distribution width (RDW) had about 9.5% higher risk. These increases were consistent across multiple statistical tests, suggesting the findings are reliable.

When researchers tested whether prostate cancer might cause these blood problems instead (reverse causation), they found no evidence of this. This strengthens the argument that the blood conditions might actually increase cancer risk, rather than cancer causing the blood problems.

The lab experiments supported these findings. When cells were deprived of B12, they showed signs of DNA damage and changes in how they divided, which are processes that could lead to cancer development.

The study identified 68 genes that appear to be involved in both B12 deficiency and prostate cancer. Two genes stood out as particularly important: B3GAT1 and SIK2, which may be key players in how B12 deficiency increases prostate cancer risk.

When researchers adjusted for other factors like inflammation markers and iron levels, the connection between RDW and prostate cancer remained significant, suggesting RDW has an independent effect. The genetic analysis showed that the connection between these blood conditions and prostate cancer is likely real and not just due to shared risk factors. The identification of specific genes provides biological plausibility—meaning there’s a reasonable mechanism by which these blood problems could affect cancer risk.

Previous research has suggested connections between B12 deficiency and various cancers, but the relationship with prostate cancer specifically hasn’t been well studied. This research adds important evidence to a relatively new area. The findings align with what we know about how B12 deficiency affects cell division and DNA integrity, which are processes involved in cancer development. However, the modest risk increases found here are consistent with B12 deficiency being one of many factors that might influence prostate cancer risk, rather than a major cause.

The study is based on genetic associations, not direct observation of people with B12 deficiency, so we can’t be 100% certain the findings apply to real-world situations. The risk increases are modest (5-10%), meaning they’re real but small. The study doesn’t tell us how long someone needs to have B12 deficiency for the cancer risk to increase. The genes identified (B3GAT1 and SIK2) need further research to understand exactly how they work. The study population was primarily of European ancestry, so findings may not apply equally to all ethnic groups.

The Bottom Line

If you have B12 deficiency, maintain normal B12 levels through diet or supplementation as recommended by your doctor (high confidence). If you have abnormal RDW, discuss this with your doctor and address any underlying causes (high confidence). Don’t assume you have high prostate cancer risk just because you have these blood conditions—the actual risk increase is small (moderate confidence). Have regular prostate cancer screening conversations with your doctor if you have multiple risk factors (moderate confidence).

Men with diagnosed B12 deficiency should be aware of this potential connection and maintain normal B12 levels. Men with abnormal RDW results should discuss the implications with their doctor. Men with family history of prostate cancer or other risk factors should consider this information when talking to their doctor about screening. This research is less immediately relevant to men without these blood conditions, though maintaining good B12 levels is healthy for everyone.

B12 deficiency typically develops over months to years, so any increased cancer risk would likely develop gradually over time. If you correct B12 deficiency, it may take months for blood markers to normalize. Prostate cancer typically develops slowly, so even if there is a connection, the actual risk remains relatively low in the short term. Regular monitoring and screening conversations with your doctor are more important than expecting immediate changes.

Want to Apply This Research?

  • Track B12 levels quarterly if you have deficiency, recording actual lab values (normal range: 200-900 pg/mL). Log RDW results from blood work when available (normal range: 11-15%). Note any B12 supplementation or dietary changes and their timing.
  • If deficient in B12, commit to consistent supplementation or dietary sources (fortified cereals, meat, fish, dairy). Set reminders for regular lab work to monitor B12 and RDW levels. Schedule annual prostate health discussions with your doctor, especially if you have multiple risk factors. Maintain a food diary noting B12-rich foods consumed.
  • Review B12 and RDW trends over 6-12 months to ensure levels are improving with intervention. Track any new symptoms like fatigue or weakness that might indicate worsening deficiency. Schedule annual prostate cancer risk assessments with your healthcare provider. Use app notifications to remind you of lab work appointments and supplement timing.

This research presents genetic associations and should not be used for self-diagnosis or to replace medical advice. If you have B12 deficiency, abnormal RDW, or concerns about prostate cancer risk, consult with your healthcare provider. The risk increases identified in this study are modest and represent one of many factors that may influence prostate cancer risk. This information is for educational purposes and does not constitute medical advice. Always discuss screening and prevention strategies with your doctor based on your individual risk factors and medical history.