Folate, RBC Folate and Vitamin B12 

Folate and Vitamin B12 are  water-soluble B vitamins that are essential for DNA synthesis and  normal production of Red blood cells, white blood cells and platelets.
Low levels of  Folate also called Vitamin B9  lead to anemia , muscle weakness, and numbness & tingling  in the extremities.

Serum Folate provides an early index of Folate status in the body while RBC Folate indicates long-term status of Folate storage in the body. 

Low Vitamin B12  can cause low hemoglobin, depression, irritability, neurologic deficits causing cognitive changes and motor weakness.



No Fasting required.


In 24 hours following blood collection.

1. Vitamin B 12 level 

2. Serum Folate level

3. RBC Folate level 

1. As part of work up for anemia in individuals with low hemoglobin

2. Individuals with symptoms concerning for Vitamin B12 or Folate deficiency

3. Pregnant women 

4. Anyone taking supplementation and wanting to know their levels. 

5. Anyone taking the prescription drug Metformin for 5 or more  years  should have Vitamin B12 checked annually 

6. If you have had gastric bypass surgery, abdominal surgery, chronic diarrhea, celiac disease, Crohn’s disease, or any chronic illness that affects absorption of food and vitamins, you maybe continuously at risk of Vitamin B12 and Folate deficiency

7. Dialysis patients are continously at risk of depeting their water solube vitamins unless they are taking a multivitamin with folate.