Start with an official trial registry, then contact the research team listed for a study that is actually recruiting. Search the specific substance—NAD⁺, nicotinamide riboside or nicotinamide mononucleotide—and the condition of interest. A paper about a completed study, a supplement sales page and an invitation to join a current trial are three different things.
The examples below are real studies with published results. Their ClinicalTrials.gov records were checked on October 6, 2026 and all three were listed as completed. They are useful reading exercises, not current enrollment offers. A changing registry status always needs a fresh check before someone makes plans. [4][5][6]
Start with the actual molecule and condition
Search ClinicalTrials.gov using the full name as well as its abbreviation. “NAD” can appear in the background description of a study whose intervention is NR, NMN or something else. Open the intervention field rather than assuming the title identifies the product. The NR and NMN comparison helps decode those names.
Next, add the condition or population. A study for diagnosed Parkinson’s disease is not a study for healthy adults seeking more energy. The Parkinson’s research review illustrates why eligibility and disease stage change the question.
Three records to practice reading
| Study and participants | Design and outcome | Finding | Main limit |
|---|---|---|---|
| NADPARK: NCT03816020 [1][4] | Oral NR; newly diagnosed Parkinson’s disease; biological target and safety | Registry: completed. Published n = 30 phase I trial. | Not recruiting; does not establish slowed progression. |
| Cognition: NCT02942888 [2][5] | Oral NR; older adults with mild cognitive impairment | Registry: completed. Published pilot found no cognitive improvement. | A brain-related title does not imply a positive memory result. |
| NICE: NCT03743636 [3][6] | NR with or without resveratrol; PAD; walking distance | Registry: completed. Published randomized walking trial. | A disease-specific functional outcome is not a general wellness claim. |
Check recruitment and locations before the results section
Read overall recruitment status, then look at individual locations and the record’s last update. “Completed” means the study has finished. “Active, not recruiting” means it is continuing without enrolling new participants. “Recruiting” is an invitation to ask about eligibility, not a guarantee that a place is available or that every listed site is open.
Do not send medical records to a contact copied from a social-media advertisement when the registry provides a research contact. Use the study’s contact information to confirm that the location, intervention and enrollment process match. If a record is old or unclear, ask the listed research institution to verify it. Registry information is supplied by the study’s responsible party; publication on the site does not certify effectiveness.
Read eligibility literally
Eligibility can involve diagnosis, age, disease stage, other treatments, laboratory values and practical requirements such as repeated visits. Inclusion criteria describe who may qualify; exclusion criteria describe reasons someone cannot take part. A person can match the general condition and still be ineligible. Only the study team can make that determination after screening.
Do not stop a medicine or alter treatment to fit an exclusion criterion without the clinicians responsible for your care. Instead, ask whether the existing treatment is compatible with the study and what happens if your health changes during participation. Trials of heart failure and acute kidney injury show why background care is part of the study design, not an optional detail.
Find the primary outcome and the comparison group
The primary outcome is the central measurement the trial was designed to test. Blood NAD⁺, memory-test performance and walking distance answer different questions. Read the time point as well as the measurement: a laboratory result after two days cannot establish long-term symptom improvement.
Check whether participants are randomized, whether there is a placebo or other comparator, and who is blinded. A before-and-after study can generate useful ideas but usually cannot attribute a change to treatment as reliably as a well-designed randomized comparison. Our long-COVID trial review shows how the controlled result and an exploratory before-and-after result can differ.
Questions to ask before consenting
- What is experimental, and what benefit is uncertain?
- What visits, tests and time commitments are required?
- What are the known risks and the plan for unexpected symptoms?
- Which costs are covered, and are travel or time reimbursements available?
- Can I continue my current care, and who coordinates with my clinician?
- What happens if I withdraw, and how will my information be handled?
Those answers should appear in the consent discussion and study materials. [7] Compensation is not evidence that a study will help you. The ability to withdraw also does not make an intervention risk free. A legitimate research conversation should make the uncertainty understandable rather than promise personal benefit.
Read the results separately from the registration
A registry entry describes a planned or conducted study. A results posting or publication reports what happened. Compare the published population, intervention and primary endpoint with the record. If a headline emphasizes a secondary biomarker while the primary clinical outcome was null, retain both facts. In the memory studies, higher NAD⁺ did not establish better cognition.
These steps help identify relevant research and ask informed questions. They cannot determine personal eligibility or replace the consent process with the study team. The point of participating is to help answer an unresolved question—not to buy a treatment with a guaranteed result.