From the Guidelines
Folate does not typically cause low neutrophils, and in fact, folate deficiency can lead to neutropenia (low neutrophil count), and folate supplementation is often used to help correct this condition. Folate is a B vitamin essential for DNA synthesis and cell division, including the production of white blood cells like neutrophils in the bone marrow. When someone has inadequate folate levels, their body may struggle to produce sufficient neutrophils, potentially resulting in neutropenia. According to the most recent guideline, the espen micronutrient guideline 1, there is no evidence to suggest that folate causes low neutrophils.
The primary concern with folate supplementation is the potential to mask a vitamin B12 deficiency, which can lead to neurological complications 1. The recommended dosage for folate supplementation is typically in the range of 400-1000 mcg daily for general health, with higher therapeutic doses (1-5 mg daily) sometimes prescribed for deficiency states 1. However, the espen micronutrient guideline 1 suggests that the upper limit (UL) for folic acid is 1 mg/day to avoid a delayed diagnosis of vitamin B12 deficiency.
Some key points to consider:
- Folate deficiency can lead to neutropenia, and supplementation can help correct this condition
- Folate supplementation should not be initiated without first ruling out vitamin B12 deficiency 1
- The recommended dosage for folate supplementation varies depending on the individual's needs and health status
- Excess folic acid is excreted in the urine, and oral administration in recommended dosages is considered non-toxic 1
If you're experiencing low neutrophil counts, it's essential to consult with a healthcare provider to determine the underlying cause, as this could be related to various factors, including certain medications, infections, autoimmune disorders, or other nutritional deficiencies. A complete blood count and further testing would be necessary to determine the specific cause of low neutrophils rather than assuming it's related to folate intake.
From the Research
Folate and Neutrophil Counts
- The relationship between folate and neutrophil counts is complex, with some studies suggesting that high serum folate levels may be associated with a decrease in neutrophil count 2.
- A study published in 2004 found that women with higher serum folate levels had a greater decrease in neutrophil count after chemotherapy, suggesting that high folate levels may exacerbate the decrease in neutrophil count caused by chemotherapy 2.
- In contrast, a study published in 2021 found that folic acid treatment reduced the risk of new-onset proteinuria in hypertensive patients with higher neutrophil counts, suggesting that folate may have a protective effect in certain contexts 3.
Folate Deficiency and Neutrophil Function
- Folate deficiency has been associated with impaired neutrophil function, including decreased phagocytosis and bactericidal ability 4, 5.
- A study published in 1982 found that correction of folic acid deficiency in patients with protein-calorie malnutrition was associated with recovery of normal phagocytic function, suggesting that folate plays a role in maintaining normal neutrophil function 5.
- Another study published in 1976 found that vitamin B12 deficiency, but not folic acid deficiency, was associated with impaired neutrophil function, including decreased metabolic activation and bacterial killing 4.
Supplementation and Haematological Parameters
- A meta-analysis published in 2018 found that supplementation with vitamin B12 or folic acid had no significant effect on haematological parameters, including neutrophil count, in community-dwelling older people 6.
- The effects of supplementation on haematological parameters did not differ by sex or age group, and no effect was found in subgroups of patients with anaemia or those treated for more than 4 weeks 6.