Active B Complex

Active B Complex

Biologically Active

60 Vegetarian Capsules ( SKU: 9424U )


  • Provides the most bioactive form of folate, Quatrefolic folate (6S)-5-MTHF*
  • Quatrefolic® folate supplementation has a greater increase in plasma folate compared to folic acid and calcium 5-MTHF*
  • Contains the most bioactive and bioavailable forms of each B vitamin, including methylcobalamin (B12), riboflavin 5’-phosphate (B2), and pyridoxal 5’-phosphate (B6)*
  • Broad-spectrum B complex, with inositol, biotin, and choline
  • Suitable for vegetarians/vegans

Feature Summary

Active B Complex includes the highly available forms of B vitamins in a unique B vitamin combination.15,16 Quatrefolic folate provides (6S)-5-methyltetrahydrofolate acid (MTHF), the active form of folate at the cellular level, which is found in circulation and is the only form able to cross the blood-brain barrier. This form of folate bypasses enzymatic conversion by methylene tetrahydrofolate reductase (MTHFR), an enzyme with common genetic polymorphisms that may impair activity. Quatrefolic acid administration has been associated with higher peak (6S)-5-MTHF levels than folic acid and calcium 5-MTHF.* It also shows a more rapid repletion of folate levels than folic acid, along with the ability to maintain homocysteine levels already within the normal range without masking a B12 deficiency.*1–4 

In addition to superior folate bioavailability, Active B Complex contains optimally bioavailable forms of each B vitamin. Benfotiamine is a lipid-soluble, bioavailable form of vitamin B1.* It may help support nerve health in the legs and feet by helping to maintain normal endothelial function.*5–7 Riboflavin 5’-phosphate and pyridoxal 5’-phosphate (PLP) are biologically active forms of B2 and B6. PLP is the most important member of the B6 group and is the active coenzyme for more than 100 enzymes, bypassing hepatic conversion to an active form.8 Active B Complex also has meaningful amounts of methylcobalamin, niacin, pantothenic acid, biotin, choline, and inositol.

Supplement Facts:


Contains no artificial colors, preservatives, or sweeteners; no dairy, starch, sugar, wheat, gluten, yeast, soy, egg, fish, shellfish, animal products, salt, tree nuts, or GMOs. Suitable for vegetarians/vegans.


No reports exist for neuropathies associated with pyridoxal 5’-phosphate, though doses of pyridoxine at 1–3 g per day have been associated with peripheral neuropathy when used in isolation.9 People sensitive to nicotinic acid may experience flushing of the skin that is generally mild and transient. 

Drug Interactions

Although several classes of drugs are known to either interfere with B12 absorption or function, such as aminoglycosides, anticonvulsants, bile acid sequestrants, proton-pump inhibitors, antihyperglycemic medications (Metformin), and acne therapy (isotretinoin), there are no known negative interactions caused by B12 supplementation with any medications.10–13 Metformin has been shown to deplete B12 and folate, and supplementation with B12 only in diabetics may be preferable.14

  1. Miraglia, N., Agostinetto, M., Bianchi, D., et al. (2016). Minerva Ginecol, 68(2), 99-105.
  2. Prinz-Langenohl, R., Brämswig, S., Tobolski, O., et al. (2009). Br J Pharmacol, 158(8), 2014-21.
  3. Bailey, S.W., & Ayling, J.E. (2018). Sci Rep, 8(1), 4096.
  4. Sicińska, E., Brzozowska, A., Roszkowski, W., et al. (2018). Int J Food Sci Nutr, 69(1), 64-73.
  5. Schreeb, K.H., Freudenthaler, S., Vormfelde, S.V., et al. (1997). Eur J Clin Pharmacol, 52(4), 319-20.
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  8. Powers, H.J. (2003). Am J Clin Nutr, 77(6), 1352-60.
  9. Head, K.A. (2006). Altern Med Rev, 11(4), 294-329.
  10. McColl, K.E. (2009). Am J Gastroenterol, 104(Suppl 2), S5-9.
  11. Aslan, K., Bozdemir, H., Unsal, C., et al. (2008). Int J Lab Hematol, 30(1), 26-35.
  12. Markkanen, T., Salmi, H.A., Sotaniemi, E. (1965). Z Vitam Horm Fermentforsch, 14(1), 66-71.
  13. Karadag, A.S., Tutal, E., Ertugrul, D.T., et al. (2011). Int J Dermatol, 50(12), 1564-9.
  14. Xu, L., Huang, Z., He, X., et al. (2013). Med Hypotheses, 81(2), 149-51.
  15. Henderson, A.M., Aleliunas, R.E., Loh, S.P., et al. (2018). J Nutr, 148(6), 885-90.
  16. Lindschinger, M., Tatzber, F., Schimetta, W., et al. (2020). MMW Fortschritte der Medizin, 162(Suppl 4), 17-27.