Research / Walking, blood readings and risks
What NAD+ research found beyond a higher blood reading
Research teams tried vitamin-related pills to restore NAD+ lost with age. Blood readings rose. Some people walked better, though the lasting health gains aren’t settled.
What the NAD+ results can help you decide
Research teams gave NMN and NR to help people make more NAD+. The teams hoped replacing an age-related loss would improve health. Blood readings rose, but a 2025 review found uneven health gains. Walking and grip tests tell you more about what changed for people.
I’d ask for evidence about the shot before having a needle put in my arm. Much less research covers shots and drips than covers pills. Added NAD+ leaves plasma, the fluid that blood cells float in, within hours. For your choice, the useful results concern the treatment you’d actually receive.
How aging can use up more of your NAD+
NAD+ helps cells carry out the changes that release food’s energy [5]. Cells can reuse NAD+ during this work; NAD+ isn’t used up. DNA repair uses NAD+ up, and controlling inflammation also draws on the supply. Proteins, substances your body makes to carry out jobs in cells, do this work [5].
In mice, aging and inflammation increased the work of a protein that uses NAD+. As that protein worked harder, the mice had less NAD+ left. Removing that protein protected the mice’s NAD+ supply and kept their cells releasing energy [2]. Aging may also reduce how much NAD+ your body makes; mouse findings don’t prove pills will help you [5].
What trials changed in NAD+ blood readings and daily movement
The eight-week NR study assigned a different amount to each group. The amounts were one hundred, three hundred or one thousand milligrams daily, written 100/300/1000 milligrams per day in the study. At one hundred milligrams daily, blood NAD+ rose 22%; at three hundred, 51%; at one thousand, 142% [4]. Those blood rises don’t prove you’d become stronger.
An NMN study gave 300–900 milligrams daily for 60 days. More NMN produced a bigger blood increase. Researchers judged 600 milligrams daily the best amount for that test [3]. That judgment doesn’t establish an amount suited to your health or long-term use.
Healthy people received 250 milligrams daily of NMN for 12 weeks. Blood readings rose at weeks 4, 8 and 12 [6]. At the study’s week 16, readings were back at the start following the end of pill use. The rise didn’t continue after people stopped NMN.
2026 brought a test of NR, NMN and nicotinamide together. NR and NMN roughly doubled blood NAD+ [15]. Nicotinamide, another vitamin-related ingredient, didn’t raise the reading. That blood change alone doesn’t establish that you’d feel healthier.
In a 10-week NMN study, women who’d passed menopause had raised blood sugar. They received 250 milligrams daily. Their muscles became more responsive to the hormone insulin, which helps muscles draw sugar out of blood [1]. Muscle and fat amounts didn’t change, and average blood sugar over recent months didn’t improve.
Older men took 250 milligrams daily of NMN during a 12-week test. Walking speed and grip in their left hands improved [7]. Their muscles didn’t become larger. You have a result for movement, rather than increased muscle size.
2023’s review couldn’t confirm improvement in most health tests [8]. The tests covered sugar handling, energy use, exercise, muscle and fat. In 2025, another review found dependable blood rises but uneven health benefits [14]. Less is known about NAD+ inside muscles and other tissues, so benefit for you remains uncertain.
How NAD+ shot mixtures and drip speed can affect your safety
Clinics arrange specially made NAD+ shots and drips only after a licensed clinician examines the patient’s case and writes a prescription. Each compounded mixture has no FDA approval, and strong proof of health gains is scarce [14]. Most reports come from small early tests or earlier patient care. You’ll need evidence for the mixture and illness your clinic proposes to treat.
Harmful material remaining from bacteria exceeded safe amounts in one mixture. The FDA placed the recall in its most serious risk category [8]. The recall shows a problem with that mixture’s safety. The recall doesn’t establish whether a safe mixture would help you, so ask the clinic about safety and benefit separately.
People received NMN and NR by swallowing pills in those trials [3][4]. A shot’s benefit isn’t established by those pill findings. Stronger shot studies would assign people by chance to NAD+ or to a treatment without NAD+, then compare how their health changed; that proof is still missing. If NAD+ enters your vein too fast, hot, red skin, nausea, or chest or belly pressure can follow [14].
What IV NAD+ reports haven’t proved about treating illness
IV means you receive treatment through a drip placed in a vein. NAD IV therapy reports mostly describe early tests or patients treated before the report was written [14]. These reports haven’t proved that the drip treats an illness. Ask what evidence the clinic has for the illness troubling you.
Blood contains cells floating in fluid called plasma. An early drip study found that, roughly two hours after the drip started, almost none of the added NAD+ remained in that fluid, even when the amount was large. The study doesn’t show where all the NAD+ went. Repeated NMN or NR pills maintained higher blood NAD+ [4][6], but the pill findings can’t prove a drip helps you.
What falling NAD+ after a drip can’t tell you about cells
NAD+ doesn’t readily enter most cells without breaking apart first. The early drip test measured NAD+ in plasma, the fluid that blood cells float in. By roughly two hours from the drip’s start, almost none of the added NAD+ remained in that fluid. The study didn’t trace all the missing NAD+, so a falling reading can’t tell you how much useful NAD+ reached your cells.
Your cells make NAD+ using ingredients supplied by swallowed NMN or NR. Blood readings stayed higher during repeated use in 8-to-12-week studies [4][6]. Stopping the pills brought the readings down. Your pill result concerns continued use; the drip result concerns how briefly added NAD+ stayed in the blood fluid.
What skin creams changed, and what happened only in mice
Studies tested skin creams containing nicotinamide, also known as niacinamide. People using the creams had slower skin aging and fewer dark patches [10]. People generally tolerated the creams. If you’re weighing a pill for your skin, cream findings don’t establish what swallowing a pill would do.
Mice received NR before being exposed to loud noise. Links from hearing cells to nerves were preserved, and the mice recovered hearing better [11]. Another mouse study found nicotinamide helped protect against glaucoma, an eye disease that harms sight; 93% of eyes were spared at the largest tested amount [13]. These mouse findings don’t establish hearing or sight benefits for you.
Skin cancer cells resisting a cancer drug made extra NAD+. Researchers blocked fresh NAD+ production, and those cancer cells lost NAD+ and energy. Mice carrying those cancers lived longer [12]. The concern is faster growth of a cancer already present, rather than proof that supplements cause new cancers in people; your cancer doctor needs to weigh this mouse evidence before you consider supplements [14].
What proof you need before judging a NAD+ shot’s worth
Pill studies with NMN or NR showed the clearest blood rises [3][4]. Added NAD+ from a drip largely disappears from plasma, the fluid that blood cells float in. Health gains from shots haven’t been established in trials [14]. Before weighing a shot’s price, ask what research on shots has shown help for people like you.
What a pill hasn’t proved about making your skin look younger
Much aging research tested rodents rather than people. Human blood rises haven’t proved that NAD+ pills give you younger-looking skin [14][8]. Separate tests found less skin aging and fewer dark patches with nicotinamide creams [10]. Those results concern cream on skin; they don’t establish the same benefit from pills.
What a NAD drip clinic needs to show about your illness
A NAD+ drip offer can come with very little proof. Reports chiefly describe small early tests or patients’ past care [14]. Added NAD+ quickly leaves the fluid in which blood cells float. Ask the clinic what has shown improvement in your illness, because these reports haven’t established that benefit.
What improved sugar handling didn’t change about body weight
The women taking NMN had a stronger muscle response to insulin [1]. This hormone travels in blood and helps muscles draw in sugar. Neither muscle nor fat amounts changed, and average blood sugar over recent months didn’t improve. A 2023 review likewise found no convincing muscle or fat change across tests [8], so you don’t have a proved weight-loss treatment.