From the Guidelines
There are currently no specific recommendations for individuals with hypercobalaminemia (elevated B12 levels) to reduce their risk of colon cancer, and instead, they should focus on established colorectal cancer prevention methods. While some studies have suggested an association between elevated B12 levels and increased cancer risk, including colorectal cancer, this relationship is not well-established as causal, and no medical guidelines recommend B12 reduction as a cancer prevention strategy 1. The American Cancer Society guidelines on nutrition and physical activity for cancer prevention suggest that diets high in vegetables and fruits have been associated with decreased risk, and diets high in red meat have been associated with increased risk of colon cancer 1.
Some key recommendations for reducing the risk of colon cancer include:
- Regular screening through colonoscopy starting at age 45 (or earlier with risk factors)
- Maintaining a healthy weight
- Limiting red and processed meat consumption
- Increasing dietary fiber from fruits, vegetables, and whole grains
- Regular physical activity, with at least 45 minutes of moderate-to-vigorous physical activity on five or more days of the week 1
- Limiting alcohol consumption
- Avoiding tobacco
Elevated B12 levels often result from underlying conditions rather than excess intake, so addressing any underlying medical issues with a healthcare provider is important 1. The elevated B12 may be a marker of other processes rather than a direct cause of cancer risk. Anyone with persistently elevated B12 levels should consult with their healthcare provider to determine the cause and appropriate management.
From the Research
Recommendations for Individuals with Hypercobalaminemia
To reduce the risk of colon cancer, individuals with hypercobalaminemia (elevated B12 levels) may consider the following:
- Avoid excessive intake of vitamin B12, as high levels have been associated with an increased risk of colorectal cancer 2
- Maintain a balanced diet rich in fruits, vegetables, and whole grains, which can provide essential micronutrients and fiber
- Consider taking non-steroidal anti-inflammatory drugs (NSAIDs) under medical supervision, as they have been shown to reduce the risk of colorectal cancer 3, 4
Dietary Considerations
- Include foods rich in folate, methionine, and vitamins B6, which have been shown to have protective effects against colorectal cancer 5
- Consume foods high in antioxidants, such as selenium, vitamins E and C, which may also have a protective effect against colorectal cancer 5
- Limit alcohol consumption, as it may interact with the protective effects of certain B vitamins, such as pyridoxal 5'-phosphate (PLP) 6
Supplement Use
- Be cautious when taking folic acid and vitamin B12 supplements, as they may increase the risk of colorectal cancer 2
- Consider consulting with a healthcare professional before taking any supplements, especially if you have a family history of colon cancer or are at high risk of developing the disease 4