HUMAN STUDIES / BLOOD CHANGED FIRST
NAD+ benefits in human studies start with higher blood levels
Pill groups had changed NAD+ blood results. Some also walked farther, gripped harder, or used insulin better. Those gains haven't returned in every test.
The firm finding is a higher NAD+ blood result
The clearest human result came from blood tests, and a draw taken after NMN or NR showed more NAD+, with one test finding more than twice as much as before [4]. Either pill can supply material that your body uses for NAD+. That higher result says nothing certain about your lifespan, strength, or chance of illness. A few studies found other gains, but the same gains haven't appeared each time for people like you.
Larger NR amounts brought larger blood changes
Among many NR pill studies, one fair test assigned 100, 300, or 1000 mg/day for 8 weeks to adults who had good general health and carried extra weight at the start. The blood rises were 22%, 51%, and 142% as the amount rose. Health problems were just as common with NR as with the placebo [4]. A placebo looks like real medicine but contains no NR. NR didn't raise bad LDL cholesterol or disturb a process that keeps cell chemistry in balance [4]. People with heart failure took 1000 mg twice daily for 21 days. Their blood NAD+ about doubled, and some signs of swelling in blood cells fell [7]. A Parkinson's disease group took 1000 mg/day for 30 days. Their brain fluid had more NAD+, showing a change but not a health gain [6]. NR can raise NAD+, yet these tests don't show which illness it can treat for you.
NMN raised blood NAD+; other gains were smaller
NMN is another form the body can use to make NAD+. One fair test gave healthy middle-aged adults 300, 600, or 900 mg/day for 60 days. At days 30 and 60, every group showed more blood NAD+. Walking distance also grew, and a test of body age didn't rise. The study called 600 mg/day the best amount tested and found no safety trouble [3]. Another test used 250 mg/day for 12 weeks. Blood NAD+ rose, then came back to its old level by 16 weeks after people stopped [9]. Older men took 250 mg/day for 12 weeks. They walked faster and had a stronger left-hand grip, but didn't add muscle [10]. Women with high blood sugar after menopause took 250 mg/day for 10 weeks. Afterward, their muscles handled insulin better, though body fat and a long-term sugar blood test stayed unchanged [1]. The FDA and supplement sellers remain at odds about the way NMN may be offered. The safety page explains that open fight; it isn't a ban.
Walking and grip improved once, not in every test
Most certain: NR raised NAD+ in blood [4]. NMN also raised it [3][9]. Larger pill amounts often brought larger changes. Less certain: older men walked faster and gripped harder in one test [10]. In other groups, muscles handled insulin better [1] or people walked farther [3]. Those gains haven't appeared in every study. Not shown: human work here has not proved fewer illnesses or extra years. A 2025 review said broad gains had little support. Few studies took samples from body tissue. Too few checked whether a person's NAD+ level falls with age [15]. Mouse results can't settle what will happen in your body.
NMN and NR pills raise blood NAD+
Yes, if you mean the blood test. The reading climbed when people swallowed either smaller starting part. NR raised the level by 22%/51%/142% at 100/300/1000 mg/day [4]. Whole NAD+ by mouth lacks that same level of proof. Changes in muscle or walking are less steady. A 2025 review found that larger health gains aren't yet proved [15].
NAD+ shots have far less proof than pills
Shots have much less study than NMN or NR pills. After NAD+ entered a vein, it quickly left plasma, the clear liquid part of blood. The study didn't show whether the body used it or threw it away. Better human work measured changes after pills, not shots [4][15]. Those pill results can't support advice about injections.
IV NAD+ soon left the liquid part of blood
Few careful tests have followed NAD+ after it entered a vein. Reviews say it soon left plasma, the clear liquid part of blood [15]. Researchers don't yet know how much the body used. Stronger human tests had people swallow NMN or NR [3][4]. Those findings don't prove that an IV drip helps. The safety page explains the risks added by a needle.
NAD+ patches haven't been shown to raise blood levels
Sellers offer patches that place NAD+ or its starting parts on your skin. Most careful tests in people had NMN or NR swallowed as pills [3][4]. None of the work here found a higher NAD+ level from a patch. Without that blood result, a seller can't use the pill studies to prove a patch helps you.