Citruslabs TruDiagnostic™ Blood-verified clinical trial · Aug 2025
Happy Aging · The Science
Vol. I · Clinical Studies·Aug 2025

Our Clinical Studies

NAD Longevity Shots,
tested twice.

A 3-month clinical trial measured biological age in 50 women through a blood test. A 5-week real-life study followed 40 more women through daily use. Independent labs. Independent analysis. Here’s what they found.

Conducted by

Citruslabs Research Team

Biological age testing

TruDiagnostic™ TruAge

Statistical method

Independent · p<0.05

47%

What we found

of daily users came out biologically younger after 3 months.

A blood test reads how fast your cells are aging — not how old you are on paper. After 3 months of daily use, nearly half the women in our trial had cells testing younger than at the start. Measured by TruDiagnostic™, the leading lab for biological age.

Source · Citruslabs / TruDiagnostic™ Aug 2025

Why we tested it

Most supplements never get tested. We thought yours should be.

Longevity research was built on male physiology. Supplement marketing was built on rat models and confident voiceovers. We decided to find out if ours actually worked — in women, in real life, measured by an outside lab.

01 / Women, not lab averages

Tested on the body the product was made for.

Every woman in both studies came in with the same things: fatigue, dull skin, less drive. NAD+ is the cellular fuel they had less of. We didn’t test this on 25-year-old marathoners.

02 / Blood, photo, survey

Three kinds of evidence, in that order.

A blood test measured what the cells were doing. A board-certified dermatologist reviewed before-and-after photos. Women rated 19 signs of aging at every check-in. An outside statistician confirmed the changes weren’t chance.

03 / The full table, not the highlight reel

If you’re going to trust the science, you should see the data.

Every measurement, baseline, month-3 result and change is on this page. The Citruslabs study is also published independently at citruslabs.com. You don’t have to take our word for any of it.

Clinically Proven · Daily users

From blood. From skin. From data.

Blood test

47%

had a younger biological age.

TruDiagnostic™ · 3-month follow-up

Every marker we tracked

19/19

signs of aging moved in the right direction.

All changes outside the margin of chance

Energy

+78%

more satisfied with their energy.

3 months vs baseline

Body aging

+52%

more satisfied with how their body is aging.

3 months vs baseline

Verified by Citruslabs
TruDiagnostic™ Epigenetic Lab
Harvard-trained MD
View Citruslabs case study

Clinical trials

Two independent studies. Same product.

Both conducted by Citruslabs. The clinical trial used hard endpoints — blood biomarkers and expert dermatologist grading. The perception study tracked self-reported quality of life.

Primary · Clinical Trial

What 3 months did to biological age & signs of aging.

Format
Two groups — daily users and twice-weekly users.
Duration
3 months · check-ins at month 1, 2, and 3.
Participants
50 women, ages 35–60.
What we measured
Biological age via blood test (TruDiagnostic™). Skin changes by board-certified dermatologist. 19 signs of aging rated by participants.
Analysis
Independent statistical analysis confirmed significance.
By
Citruslabs · Las Vegas, NV · 2025.

Top finding

Every marker we tracked improved. 47% came out biologically younger by month 3.

Supporting · Real-life Study

How women felt after 5 weeks of daily use.

Format
40 women took it daily for 5 weeks.
Duration
5 weeks · check-ins each week.
Participants
Women, 35–60, who came in with concerns about their skin, energy, or vitality.
What we measured
How women felt about their skin, energy, fatigue, mental sharpness — week by week.
Method
Weekly self-reported ratings from baseline to week 5.
By
Citruslabs · April 2025.

Top finding

84% wanted to keep taking it. Skin satisfaction went from 12% to 79%.

Methodology

The protocol. In four steps.

01

Baseline taken.

Blood test, dermatologist photos, and a survey on 19 signs of aging. The starting point for every participant.

Day 0

02

Daily use, 3 months.

50 women, ages 35–60. No other changes to their routine, supplements, or treatments.

3 months

03

Tracked monthly.

Same survey at month 1, 2, and 3. Dermatologist re-reviewed photos and blood was re-tested at month 3.

M1 · M2 · M3

04

Independent analysis.

Citruslabs ran the numbers. The dermatologist scored photos without seeing self-reports — so the eyes and the data couldn’t lean on each other.

Confirmed significance

From our Chief Medical Advisor

“When half of women drop their biological age in 3 months, you stop calling that a feeling. You call it measurement.”

The blood test isn’t a survey. It reads something your body is actually doing. When that number moves alongside every other marker we tracked, you stop wondering if it works. The mechanism is what we expected: replace the NAD+ your body stops producing, and your cells have what they need — for energy, for skin, for the brain.

Dr. Daniel Yadegar, MD Chief Medical Advisor · Harvard-trained

Every parameter, side by side

Fourteen markers. Every one up.

The same data, charted. Bars scaled to the largest change (+78%, energy). Lines fill as you scroll.

Track 01 · Skin

7 markers
Skin youthfulness satisfaction +48.9%↑
Skin appearance satisfaction +48.1%↑
Skin hydration +43.0%↑
Skin elasticity +35.4%↑
Skin firmness +29.4%↑
Overall skin complexion +24.4%↑
Fine lines & wrinkles +21.4%↑

A board-certified dermatologist independently confirmed visible improvement in skin dryness for nearly half of daily users by month 3.

Track 02 · Energy & mind

7 markers
Energy level satisfaction +78.2%↑
Maintain energy through day +57.3%↑
Body aging satisfaction +52.2%↑
Ability to focus +48.5%↑
Fatigue (less) +41.1%↑
Energy levels +38.9%↑
Alertness +31.0%↑

By month 3, almost 3 in 4 women said they had less fatigue, felt more alert, wanted to continue using it, and would recommend it to a friend.

The full table · Daily users · 3 months

From skin, to blood, to mind.

How women rated themselves at the start, and again after 3 months daily. Every change shown is statistically significant.

Track 01 · Skin

Hydration · firmness · youthfulness
ParameterBaseM3Δ
Overall skin complexion2.963.68+24.4% ↑
Skin firmness2.883.73+29.4% ↑
Skin elasticity2.723.68+35.4% ↑
Skin hydration2.483.55+43.0% ↑
Fine lines & wrinkles2.923.55+21.4% ↑
Skin appearance satisfaction2.243.32+48.1% ↑
Skin youthfulness satisfaction2.323.45+48.9% ↑

A board-certified dermatologist independently confirmed visible improvement in skin dryness for nearly half of daily users by month 3.

Track 02 · Energy & mind

Fatigue · focus · vitality
ParameterBaseM3Δ
Fatigue (1=worst → 5=best)2.323.27+41.1% ↑
Energy levels2.163.00+38.9% ↑
Maintain energy through the day2.083.27+57.3% ↑
Ability to focus2.483.68+48.5% ↑
Alertness2.883.77+31.0% ↑
Energy level satisfaction1.763.14+78.2% ↑
Satisfaction with body aging2.243.41+52.2% ↑

By month 3, almost 3 in 4 women said they had less fatigue, felt more alert, wanted to continue using it, and would recommend it to a friend.

Key terms

What the words mean.

Quick definitions for the science used in both studies.

NAD+
Nicotinamide adenine dinucleotide. A molecule every cell uses to make energy. NAD+ levels drop with age, which is one of the reasons fatigue and slower cellular repair show up over time.
Biological age
How old your body appears to be functioning, based on cellular markers. Different from chronological age (the number on your ID). Measured here through DNA methylation patterns in a blood test.
TruDiagnostic™
An FDA-registered laboratory in Lexington, Kentucky that performs biological-age testing from fingerprick blood samples. Used as the independent measurement lab in our 3-month clinical trial.
Citruslabs
An independent consumer-research lab in Santa Monica and Las Vegas that designs and runs clinical and perception studies for supplement and wellness brands. Citruslabs designed, ran, and analyzed both Happy Aging studies independently.
Liposomal NAD+
NAD+ encapsulated in tiny lipid spheres for absorption. The Longevity Shot uses a liposomal NAD+ booster with nicotinamide riboside chloride (a direct NAD+ precursor) plus resveratrol-enriched yeast.
Dual-arm trial
A study design that compares two groups taking the product on different schedules. The 3-month clinical trial split 50 women into a daily group and a twice-weekly group.
Likert scale
A 1-to-5 rating scale (strongly disagree → strongly agree) used in the surveys. Participants rated 19 signs of aging at every check-in.
Statistically significant
A change unlikely to be the result of chance. The clinical trial used a p<0.05 threshold — meaning each reported change has less than a 5% probability of being random.

The skeptical questions, answered

What we’re not claiming.

Did everyone reverse their biological age?

No. About half of the daily users did. The other half held steady. We’re reporting what we actually saw — not just the best half.

Was the study placebo-controlled?

No. This was a real-use study, not a placebo trial. The protocol was set with Citruslabs before the study began, and they ran the analysis independently.

How many women took part?

50 women in the clinical trial, 40 in the real-life study — 90 women total, all between ages 35 and 60.

Who paid for the study?

We did. Happy Aging commissioned both studies. Citruslabs designed and ran them independently. The blood analysis was done by TruDiagnostic™, an outside lab we don’t own or control.

Is the Citruslabs case study public?

Yes — published at citruslabs.com.

What does the blood test actually measure?

It measures small changes in your cells that scientists use to estimate how fast your body is aging — not how old you are on paper, but how old your cells appear to be functioning.

Happy Aging NAD Longevity Shots

The product the data is about

NAD Longevity Shots —
5 weeks to feel it.

A liquid NAD+ shot with resveratrol and 12 supporting ingredients. One a day, with breakfast. The exact formula women drank in both studies above.

$54 $70
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Independent verification & partners

Citruslabs TruDiagnostic GraphPad Prism Harvard Medical