Your father is seventy-four. His geriatrician just said the forgetfulness looks like mild cognitive impairment, not dementia yet, and handed you a sheet on memory clinics and follow-up. That night a neighbor swears an “NAD booster” fixed her husband’s fog because “it doubles blood NAD and protects the brain.” Your father asks whether he should start one before the next appointment.
A 2026 phase 2 pilot tested that idea with nicotinamide riboside, a common NAD precursor. Blood NAD rose. Thinking scores did not.
What the Delaware MCI pilot found
Martens and colleagues reported a twelve-week, double-blind, randomized, placebo-controlled pilot in Alzheimer’s and Dementia in 2026. Forty-two older adults with amnestic mild cognitive impairment finished the study: twenty-two on nicotinamide riboside and twenty on placebo. Adherence was similar, and the authors reported no serious adverse effects tied to the supplement.
Blood NAD roughly doubled in the nicotinamide riboside group. The primary outcome, cognitive function, did not improve versus placebo. Total cerebral blood flow and blood pressure, the main secondary outcomes, also did not improve. Exploratory looks at regional blood flow, including the hippocampus, hinted at possible local changes that the authors said need longer, larger studies.
In plain terms: the pill moved a blood marker. It did not move the thinking tests that matter to a family waiting on a diagnosis.
How this fits other NAD+ stories
Everyday Brief has covered NAD precursors that raise blood markers without proving anti-aging, IV drip studies that mainly recorded tolerability, and the large NOPARK phase 3 trial in Parkinson disease that found no disease-modifying benefit from nicotinamide riboside. Mild cognitive impairment is a separate question with its own pilot. Raising NAD in the blood is not the same as protecting memory.
MedlinePlus notes that no medicine is proven to treat mild cognitive impairment today, and it urges people to review medicines and other medical causes of memory trouble with a clinician. That remains the practical path after a new MCI label.
What to bring to the next geriatric visit
Bring the memory changes themselves: what is new, how fast it changed, and which medicines or sleep problems might contribute. Ask about formal cognitive testing, a medication review, hearing and vision checks, and a follow-up schedule. If an NAD booster still comes up, ask whether the neighbor is describing this MCI pilot or something else, and note that cognition was the outcome that did not move.
Doubling a lab number can feel like progress. For mild cognitive impairment, the pilot says it was not enough.
Not medical advice.
Sources
- Martens CR et al. A phase-II randomized controlled pilot study of nicotinamide riboside supplementation in older adults with amnestic mild cognitive impairment. Alzheimers Dement, 2026 (PubMed)
- Full text: Martens et al. 2026 NR in aMCI (PubMed Central)
- MedlinePlus: Mild cognitive impairment
- MedlinePlus: Memory
Related reading
- NOPARK: an NAD booster did not help Parkinson disease
- NAD+ precursors raise blood markers, not proof of anti-aging
- What NAD+ IV drip studies recorded
By The Everyday Brief. AI-assisted drafting with human editorial review. Sources fetched 2026-10-14 PT. Not medical advice.