NIACIN (VITAMIN B3)

What is Niacin?

Niacin, also called vitamin B3, belongs to the B vitamin family. Niacin helps convert the food we eat into energy to power our cells. We can get niacin from the food we eat or from supplements.

What does niacin do in the body?

In our bodies, vitamin B3 helps create nicotinamide adenine dinucleotide, or NAD+ for short, which is used in many metabolic reactions [^[1]]. NAD+ affects cellular functions beyond energy metabolism, such as DNA repair, cellular aging, and immune system function [^[2]]. NAD+ also reduces the inflammatory response, so by synthesizing NAD+, vitamin B3 helps temper inflammation.

How can niacin help alleviate certain Long COVID symptoms and/or pathophysiology? 

The immune response to COVID-19 and the inflammation that may follow and persist in Long COVID, threatens NAD+ metabolism. COVID-19 severity and persistence of symptoms after acute infection rely upon the robustness of the patient’s NAD+ salvage pathway [^[2]]. Long COVID, in many ways, resembles pellagra, or vitamin B3 deficiency, similarly characterized by increased inflammation. Therefore, vitamin B3 supplementation may help restore the NAD+ balance in Long COVID [^[2]].

What else should I know about niacin?

Niacin supplements are known for an acute flush reaction, which can worsen when taken with other vitamins, such as zinc. Also, niacin can increase the risk of bleeding events when combined with selective serotonin reuptake inhibitors or non-steroidal anti-inflammatory drugs and increase the risk of rhabdomyolysis when taken together with statins [^[3]].