Folate, also known as vitamin B9, is a water-soluble nutrient with a significant role in numerous bodily functions. It is involved in processes such as DNA synthesis, cell division, and the formation of red blood cells. While obtaining sufficient folate is important for overall health, both inadequate and excessive levels can be a concern, prompting investigation into their underlying causes.
How Folate Levels Are Determined
Folate levels are typically assessed through blood tests, measuring concentration in serum or red blood cells. Serum folate reflects recent intake, while red blood cell folate indicates the body’s status over a longer period, up to four months. A normal serum folate level generally ranges from 2 to 20 ng/mL. Levels above 20 ng/mL are considered elevated. High folate levels are often identified during routine blood work or when investigating other health issues.
Medical Conditions Leading to High Folate
One common reason for elevated folate levels is excessive intake of folic acid, the synthetic form of folate, from dietary supplements or fortified foods. Folic acid requires conversion by the body into an active form, and consuming it in large quantities can lead to a buildup of unmetabolized folic acid in the bloodstream. This accumulation occurs because the body can only process a limited amount of synthetic folic acid at one time.
High folate levels can also signal an underlying vitamin B12 deficiency due to their interconnected roles in metabolism. When vitamin B12 is insufficient, folate can become trapped in an unusable form within cells, leading to its accumulation in the blood.
Certain genetic variations, such as those in the MTHFR gene, can affect how the body processes folate. Individuals with MTHFR gene mutations may have a reduced ability to convert folic acid into its active form, 5-methyltetrahydrofolate (5-MTHF). This reduced conversion can contribute to unmetabolized folic acid accumulation in the body.
Impaired kidney function can also lead to elevated folate levels. The kidneys excrete excess water-soluble vitamins, and when their function is compromised, this excretion process is less efficient, allowing folate to build up in the bloodstream.
Liver dysfunction can similarly impact folate metabolism and storage, potentially leading to elevated levels. The liver is central to processing and storing folate, and various liver diseases can disrupt these functions.
Some types of cancer, particularly certain leukemias, have been linked to increased folate levels. Rapidly dividing cancer cells have a high demand for folate to support DNA synthesis and growth. The body’s response to these malignancies can release higher levels of folate into the bloodstream.
Recognizing Symptoms of High Folate
High folate levels often do not produce noticeable symptoms directly. However, a significant concern is high folate’s ability to mask vitamin B12 deficiency symptoms. While high folate might correct the anemia common in B12 deficiency, it does not prevent neurological damage. This can lead to symptoms like numbness or tingling in the hands and feet, memory problems, cognitive changes, mood disturbances, vision problems, and muscle weakness.
Some individuals with elevated folate levels might experience non-specific symptoms. These include digestive upset, such as nausea, bloating, or abdominal cramps. Other reported symptoms include difficulty concentrating, irritability, or sleep disturbances. In rare instances, high folate levels have been associated with seizures.
When to Consult a Doctor
If a blood test reveals high folate levels, consult a healthcare professional. This is especially important if you have unexplained symptoms, particularly neurological ones like numbness or memory issues. If you are taking high-dose folate supplements and have concerns about potential effects, discuss this with your doctor. Only a healthcare professional can accurately diagnose the cause of elevated folate levels and provide appropriate guidance and management.