NAD+ nasal spray vs oral NAD+: What are you comparing?
Is NAD+ nasal spray better absorbed than oral NAD+?
Available evidence doesn't establish that NAD+ nasal spray is better absorbed than oral NAD+. Much of the human oral research uses NR or NMN, which are precursors and differ from NAD+ itself. See what nasal absorption studies would need to measure.
Start with the ingredient, then the route
Say one page describes a bottle of nasal NAD+ and links to a study where people swallowed NR capsules. The comparison just changed two things at once. The ingredient changed from NAD+ to NR and the route changed from nasal to oral. Whatever the capsule study measured, it measured after people took that capsule. Learn the difference between NAD+ and its precursors.
| Format | Molecule | What to check when reading the evidence |
|---|---|---|
| Nasal NAD+ spray | NAD+ | Does the study match the nasal formulation and measure human exposure or a human outcome? |
| Oral NAD+ product | NAD+ | Did participants actually take NAD+ by mouth, and did the study use a comparable formulation? |
| Oral NR or NMN product | A precursor | Which precursor was tested, in whom, and was the result a biomarker or a change people could feel or use? |
What can the capsule studies teach us?
In one trial, oral NR elevated NAD-related markers in healthy middle-aged and older adults. A different trial in men with obesity found no improvement in insulin sensitivity with NR. They asked different questions in different groups. Read the outcome before turning a study into a product comparison. Read the older-adult trial. · Read the insulin sensitivity trial.
Compare like with like
For an absorption claim, look for a defined measure of exposure, the compound measured, and when and where it was measured. For a claim about feeling or functioning better, look for a study that measures that outcome. Route names alone can't rank the two.