The Claim

Among adults with type 2 diabetes, serum vitamin B12 levels below 369.1 pg/mL and above 703.5 pg/mL are both associated with a significantly higher risk of cardiovascular disease mortality compared to serum vitamin B12 levels between 369.1 and 506.0 pg/mL, indicating a U-shaped relationship in which both low and high levels of vitamin B12 may be harmful.

Source: Associations of Serum Folate and Vitamin B12 Levels With Cardiovascular Disease Mortality Among Patients With Type 2 Diabetes

What the research says

Supports is higher

Support is ahead, but a single strong opposing study can change this.

Supports
59score
Challenges
0score

These are independent scores, not a percentage. Higher-grade studies count more, so a single strong opposing study can outweigh several weaker ones.

Correlation
1 study reviewed
In plain English

For people with type 2 diabetes, having too little or too much vitamin B12 in the blood might increase the chance of dying from heart disease — the safest range seems to be in the middle.

See the scientific wording

Among adults with type 2 diabetes, serum vitamin B12 levels below 369.1 pg/mL and above 703.5 pg/mL are both associated with significantly higher risk of cardiovascular disease mortality compared to levels between 369.1–506.0 pg/mL, indicating a U-shaped relationship where both deficiency and excess may be harmful.

What the research says

1 study
  1. Study: Associations of Serum Folate and Vitamin B12 Levels With Cardiovascular Disease Mortality Among Patients With Type 2 Diabetes

    This study found that adults with type 2 diabetes who have either too little or too much vitamin B12 in their blood are more likely to die from heart disease, compared to those with levels in the middle range — just like the claim says.

Score breakdown, mechanism chain, raw evidence, ideal studies needed & 1 supporting studies

Fit Body Science verdict — we translate health claims into clear verdicts backed by peer-reviewed research.

Not medical advice. For informational purposes only. Always consult a qualified healthcare professional before making health decisions.