Niacinamide Accelerates Recovery in COVID-19 Patients, Clinical Trial Shows

• NAD⁺ supports DNA repair and cellular stress responses — Certain enzymes in your body, like poly (ADP-ribose) polymerase (PARPs) and sirtuins, rely on NAD⁺ to repair damaged DNA and regulate cell survival under stress. These enzymes consume NAD⁺ as they work. This is why during periods of inflammation, infection, or injury, NAD⁺ levels fall sharply. As levels drop, your body’s ability to maintain homeostasis weakens.

• Niacinamide replenishes NAD⁺ directly and efficiently — As you can see in the illustration below, when NAD is used up, it gets broken down into niacinamide. The body then recycles niacinamide through a salvage pathway, converting it into nicotinamide mononucleotide (NMN) and then back into NAD⁺. This makes niacinamide not just a precursor, but also the natural product of NAD⁺ turnover.

• Activating NAMPT is key to effective NAD⁺ restoration — The enzyme NAMPT controls how much NAD⁺ is produced from niacinamide. While NMN supplements have become popular, NMNAT (the enzyme that converts NMN to NAD⁺) does not regulate the overall pace.

Because NAMPT determines the flow through the entire pathway, supporting its activity is more essential for restoring NAD⁺. So, flooding your body with NMN is not going to be as useful as using small amounts of niacinamide and activating NAMPT.

• Patients received a dual-form nicotinamide regimen — Those in the treatment group were given 1,000 milligrams of nicotinamide per day, delivered in two tablet forms. One was a conventional oral tablet, while the other was formulated to release in the colon, where most of the gut microbiome resides. This approach was designed to support microbiome-targeted recovery.

• Early improvements were seen by week two — Participants receiving nicotinamide were more likely to report restored physical performance and an improved ability to handle everyday tasks. These gains were especially notable in individuals with risk factors for more severe illness, and they appeared during the active four-week supplementation period.

• Long-term benefits emerged at six months — Patients who had taken nicotinamide during the initial infection were less likely to report persistent long COVID symptoms, such as fatigue or difficulty concentrating. The effect was most pronounced in those who showed early recovery, suggesting that timely support influences long-term outcomes.

• Nicotinamide appeared to protect the gut microbiome — Microbiome analysis revealed signs of metabolic stress and gene-level disruption in placebo participants two weeks after infection. In contrast, those who received nicotinamide had a more stable microbial profile. Their gut bacteria maintained more balanced gene expression patterns, suggesting better systemic regulation. According to Professor Philip Rosenstiel, who led the microbiome studies:

“The microbiome of COVID-19 patients still shows a kind of emergency metabolism around two weeks after the onset of the disease, in which the body obviously tries to compensate for the known deficits in important metabolic factors by upregulating other metabolic processes.

We did not observe these changes in the nicotinamide study group — probably because the deficiency could be compensated by administering nicotinamide. At the same time, we observed a faster physical recovery in these cases. The positive influence on the microbiome is apparently related to the faster recovery.

This is the first time we have shown that influencing the microbiome, in this case through supplementation of a nutrient, can have a positive effect on a viral infection. This is an important milestone in clinical research.”³

• Niacinamide reduced death in severe AKI cases — A total of 201 hospitalized COVID patients with confirmed AKI were enrolled. Ninety patients at one hospital received 1 gram of niacinamide daily, while 111 patients at a second hospital received the same care protocol without niacinamide.

Among patients with advanced (stage 2 or 3) AKI, those who received niacinamide had an 80% lower risk of death compared to controls. Kidney function also stabilized, with creatinine levels remaining steady in the niacinamide group over 10 days, while steadily worsening in the control group.

• NAD⁺ loss is central to COVID-related kidney dysfunction — COVID-related AKI appears to deplete NAD⁺ through both increased breakdown and impaired production. Without sufficient NAD⁺, these cells no longer sustain energy-intensive filtration and transport functions, increasing the risk of dysfunction and death. Niacinamide, as a direct precursor, restores NAD⁺ levels and helps the kidney maintain its energy demands under stress.

• The benefit was specific to more advanced kidney injury — The benefits were not seen in milder cases of AKI, which suggests that the severity of NAD⁺ depletion determines the extent of benefit. Individuals with early-stage AKI likely retain enough NAD⁺ to recover naturally, while those with more advanced injury require supplementation to prevent further decline.

• Improves body composition and physical energy — In animal models of obesity, niacinamide supplementation led to a 47% reduction in body fat after just three weeks. Treated mice also showed gains in lean mass and increased physical activity, even across different dietary conditions. This shift is driven by enhanced mitochondrial biogenesis and increased fat oxidation, both of which convert stored fat into usable energy more efficiently.^5,6

• Limits damage from lipid peroxidation — Stored polyunsaturated fats (PUFs), especially linoleic acid (LA), convert into harmful inflammatory compounds, with one of the most toxic byproducts being 4-HNE, an aldehyde that plays a causative role in heart failure.⁷ Fortunately, the enzyme aldehyde dehydrogenase (ALDH) deactivates 4-HNE, and the best way to increase the activity of this enzyme system is to make sure you have sufficient NAD⁺.

• Protects brain cells and slows neurodegeneration — Niacinamide helps reduce the risk of cognitive decline by supporting neuronal energy supply and inhibiting overactive enzymes like PARP-1 and SIRT1. These enzymes, when unchecked, drain NAD⁺ and accelerate brain cell stress.⁸

• Strengthens the gut barrier — The intestinal lining requires high levels of ATP to stay intact. When energy runs low, the gut becomes permeable, allowing bacterial endotoxins like LPS to enter the bloodstream. This contributes to widespread inflammation and metabolic dysfunction. In models of alcohol-induced gut injury, niacinamide restored NAD⁺ and ATP levels in intestinal cells and tightened the barrier.⁹

• Supports kidney function beyond acute illness — Beyond its acute protective role in COVID-related kidney injury, niacinamide may offer broader support for kidney function. NAD⁺ depletion contributes to chronic kidney disease (CKD) by impairing glucose oxidation and promoting inefficient fat metabolism.

Niacinamide helps restore the NAD/NADH ratio, preserve mitochondrial function, and reduce stress signaling in kidney cells. It also tempers the activity of NAD-consuming enzymes that accelerate damage.¹⁰

• Helps maintain healthy heart muscle and prevent fibrosis — Heart failure is closely tied to declining NAD⁺ in cardiomyocytes, the muscle cells responsible for contraction. When energy levels fall, these cells begin releasing pro-fibrotic signals, leading to tissue stiffening and loss of function.

Niacinamide helps sustain ATP production and prevent this transition, offering early protection in models of cardiac stress. Though human trials are still emerging, current findings point to its potential in preserving long-term cardiac resilience.^11,12

• A practical daily approach involves small, evenly spaced doses — For optimal health, I recommend taking 50 milligrams of niacinamide three times per day. This dosage has been shown to optimize energy metabolism and boost NAD⁺ levels, which are foundational for everything else to work. It can be taken four times a day if you space them out. Take a dose as soon as you get up, another before going to bed, and two more evenly spaced between those times.

• Higher doses of B3 cause adverse effects — The problem with taking too much vitamin B3, whether in the form of niacin or niacinamide, is that it might backfire and contribute to cardiovascular disease, as documented by the Cleveland Clinic.¹³

Also, please note that although niacinamide and niacin are both forms of vitamin B3, niacin will not activate NAMPT like niacinamide, so it is best to use niacinamide. Additionally, niacinamide, unlike niacin, will not cause flushing, which is due to a large release of histamine.

• Make sure you’re getting all the other B vitamins — Other B vitamins are important for good health, including optimal mitochondrial function — especially regular niacin, riboflavin, and folate. Decreased mitochondrial function is often due to a deficiency in B vitamins, and that’s easy to fix with a low-dose, high-quality B complex.

As for food sources, vitamin B3 is found in grass fed beef and mushrooms.¹⁴ Vitamin B6 is plentiful in grass fed beef, potatoes, and bananas.¹⁵ You’ll find folate, or vitamin B9, in spinach, broccoli, and asparagus.¹⁶ Vitamin B12-rich foods include grass fed beef liver, wild rainbow trout, and wild sockeye salmon.