Leap Years Review 2026: Clinical Trial, Pros, Cons and Label Gaps

Leap Years Pros and Cons

Pros

• Published dog study in Scientific Reports tied to the Leap Years LY-D6/2 product system.
• Trial described as randomized, blinded and placebo-controlled.
• Clear two-chew routine: LY-D2 for daily NAD support and LY-D6 for the monthly NAD-plus-senolytic combination days.
• Named veterinary and scientific figures are visible, including the NC State trial investigator.
• The brand says the product does not contain NMN, which rules out one common assumption about the NAD ingredient.

Cons

• The exact NAD booster is not publicly named.
• The exact senolytic compound is not publicly named.
• The 600 mg LY-D6 amount is not split into NAD-booster milligrams versus senolytic milligrams.
• A public lot-specific COA lookup, named testing lab and itemized test panel were not visible in the sources reviewed.
• Public owner discussion includes serious unverified tolerance and illness anecdotes, so older dogs with medical history deserve a veterinarian conversation before use.
• Manufacturing and sourcing are described at a quality-system level, but the exact facility and ingredient origins are not easy to inspect.

Why Leap Years Is Different From Most Dog Longevity Supplements

Leap Years is not just another senior chew built around familiar ingredients. Its main claim to attention is a published dog study connected to its LY-D2 and LY-D6 routine.

That changes the review. Many pet supplement brands borrow evidence from individual ingredients, human studies, or general mechanism papers. Leap Years points to a published study of the LY-D6/2 regimen in aged dogs. For a pet parent shopping in the longevity category, that is a real distinction.

The harder question is what the trial does not solve. A study can make a product worth reading about, but it does not automatically tell the buyer every active compound, batch result, manufacturing detail or subscription term they may want before giving it to an older dog.

What the Leap Years Dog Trial Actually Changes

The strongest public evidence for Leap Years is the Scientific Reports paper published in 2024. The study is described as randomized, controlled and double-blinded, and it was conducted through North Carolina State University College of Veterinary Medicine.

That matters because the evidence is tied to the Leap Years LY-D6/2 regimen, not just to a general NAD ingredient or a generic senolytic idea. It gives the brand a stronger evidence anchor than a page that only says “science-backed” and then links to unrelated ingredient research.

A pet parent should not turn the study into claims that Leap Years reverses aging, extends lifespan, treats disease, prevents disease or guarantees a visible change in an individual dog. The useful conclusion is narrower: Leap Years has unusually relevant dog-study evidence for a supplement in this category, but the exact retail formula still has to be judged by its label, testing and quality disclosures.

The LY-D2 and LY-D6 Label Gap

Leap Years describes a two-chew routine:

This is the central label issue. The public label gives a buyer the routine and the functional totals. It does not let the buyer compare the product by exact compound, exact active dose or active-by-active formula architecture.

For an older dog, that is not a small detail. If a veterinarian wants to screen the product against medications, diagnoses, diet restrictions or other supplements, unnamed active compounds make that conversation harder.

Testing, COAs and Manufacturing Disclosure

Leap Years says its chews are tested in a registered laboratory and describes quality-system signals such as cGMP, NASC registration and FDA-registered facilities. Those are useful baseline statements.

They are not the same as a public lot-specific COA.

What was still hard to verify from public sources:

• the name of the testing laboratory;
• a public COA lookup tied to the lot a customer receives;
• whether the test panel includes potency, active identity, contaminants, microbes, pesticides or other category-relevant checks;
• the manufacturing facility name, city and state;
• ingredient suppliers or ingredient countries of origin.

This does not prove that Leap Years lacks internal testing or quality controls. It means the buyer cannot inspect those details before purchase as easily as they can inspect the trial link.

Public Transparency Score: 64.5/100

Leap Years earns 64.5/100 under La Petite Labs' 2026 Brand Transparency Rubric. This is a public-verifiability score, not an effectiveness score. It asks how much a buyer can inspect before purchase: label detail, rationale, evidence, expert visibility, testing, manufacturing disclosure, claim discipline and ease of access.

The score explains the tension in the page: Leap Years is far above average on category-relevant evidence, but not equally strong on the public details that let a buyer or veterinarian inspect exactly what is in the jar and how each batch is verified.

Expert Visibility and What It Does Not Prove

Leap Years has more named expert visibility than many pet supplement brands. Public materials connect Dr. Natasha Olby, Vet MB, PhD, DACVIM Neurology, to the NC State study. They also identify Dr. Ginny Rentko, VMD, DACVIM, in a veterinary leadership role, and surface several practicing veterinarians in brand materials.

That is useful. Named people are more accountable than anonymous “vet-formulated” language.

The boundary is important: named experts do not replace formula disclosure. They do not tell the buyer which NAD precursor is used, which senolytic compound is used, whether every batch is potency-tested, or which lot-level COA applies to a jar.

David A. Sinclair, A.O., Ph.D. appears in the brand’s aging-science context. The sources reviewed do not support saying that he formulates, advises, endorses or works for Leap Years.

Owner Reviews, Price and Subscription Fit

Leap Years has a real but uneven owner-review footprint. The brand-owned product page showed a visible 4.8/5 rating from 26 reviews when checked, while the Amazon listing showed 4.4/5 from 57 global ratings. Those are useful signals, but they are still small review surfaces for a product making advanced senior-dog claims.

The positive public review pattern is easy to understand: owners and brand-hosted testimonials talk about more energy, better engagement, easier movement, cognitive brightness and dogs accepting the beef-flavored chew routine. That matches why people shop for Leap Years in the first place. They are usually not buying a basic multivitamin; they are hoping an older dog feels more present, more mobile and more like themselves.

The caution is that the most useful owner discussion is not all positive. A Reddit Golden Retrievers thread includes people asking whether anyone has used LeapYears, whether it can really extend health, what senolytic ingredient is being used, and whether severe illness anecdotes should change the buying decision. Several commenters describe alleged pancreatitis, renal or liver problems, lameness, digestive upset or refusal after use. Other commenters report no problems or say their dogs seemed to have more energy or easier movement.

Those Reddit comments are not clinical evidence and do not prove causation. They do matter as buyer-risk context. Leap Years itself states in FAQ/product materials that transient side effects reported in under 1% of dogs include digestive upset, itchiness and neurological signs such as agitation, drowsiness or hind-leg weakness. For an older dog, especially one with pancreatitis history, kidney/liver disease, appetite problems, medications or recent cancer workups, owner reviews should push the conversation toward a veterinarian and toward clearer ingredient/testing questions.

Price still matters because Leap Years is a repeat-use senior-dog routine. The price snapshot checked on 2026-06-22 showed these public listing examples:

As a simple 31-chew example, if one 31-count jar covers the dog's 31-day routine, the $54.99 one-time listing equals about $53.22 per 30 days. The $52.24 subscription listing equals about $50.55 per 30 days. The $69.99 listing equals about $67.73 per 30 days on the same assumption. Recheck current dog-size directions before relying on that math, because large-dog economics and renewal timing can change the real monthly cost.

Treat those as dated snapshots, not live prices. Before subscribing, check the current jar count, dog-size directions, renewal timing, cancellation terms, shipping cost and refund policy. The evidence story may justify a closer look, but the routine still has to make sense month after month.

Where La Petite Labs Fits

Hollywood Elixir is relevant only for the part of this search that is about senior or longevity support. It should not be presented as a copy of Leap Years’ studied LY-D2/LY-D6 regimen.

Leap Years remains the more direct fit when the buyer specifically wants the studied proprietary NAD-plus-senolytic system and is comfortable with undisclosed active identities. Hollywood Elixir is more relevant when the buyer wants a readable daily longevity-support routine rather than a proprietary two-chew intervention.

Final Verdict: Should You Try Leap Years?

Leap Years is worth taking seriously because the dog study is real and unusually relevant for the pet longevity category. It is not a throwaway “science-backed” supplement page.

But the buying decision is not finished by the trial. Before using it for an older dog, a careful pet parent should still get answers to the label and testing questions the public pages leave open.

Questions to bring to your veterinarian (and to Leap Years support):

• What is the NAD precursor in LY-D2 and LY-D6? The brand says it is not NMN, but does not name it.
• What is the senolytic compound, and how is the 600 mg LY-D6 amount split between the NAD booster and the senolytic?
• Can Leap Years provide the COA for the specific lot I would receive, and which laboratory issued it?
• What does the test panel cover — potency, identity, contaminants, microbes?
• Given my dog's medical history and medications, do the trial's enrolled-dog criteria resemble my dog at all?

If those questions come back with acceptable answers, Leap Years may deserve a place in the conversation. If you want every active and batch detail visible before purchase, Leap Years is still harder to inspect than its clinical evidence first suggests.

FAQ

Is Leap Years legit?

Yes. Leap Years is a real dog supplement brand with a published dog study tied to its LY-D6/2 product system, named veterinary figures and public product pages. The stronger question is whether its proprietary formula disclosure and testing visibility meet your standard before purchase.

Is Leap Years backed by a real dog study?

Yes. Leap Years points to a randomized, blinded, placebo-controlled study in aged dogs published in Scientific Reports in 2024. That is the strongest reason to treat the brand seriously.

Was the study on Leap Years itself or only on ingredients?

The study was tied to the Leap Years product system, not merely to unrelated ingredient research. That makes it more relevant than a generic science page, though the retail formula still remains proprietary at the active-identity level.

What are LY-D2 and LY-D6?

LY-D2 is the brown daily chew described as 200 mg of an NAD Booster. LY-D6 is the golden combination chew described as 600 mg of NAD Booster plus senolytic. The exact active compounds are not publicly named in the sources reviewed.

Does Leap Years contain NMN?

The brand says Leap Years does not contain NMN. That rules out one possible NAD ingredient, but it does not identify the NAD precursor the product does use.

Does Leap Years publish COAs?

A public lot-specific COA lookup was not visible in the sources reviewed. Buyers who require batch documentation should ask Leap Years for the COA tied to the specific lot they would receive.

Does Leap Years name its testing lab?

Leap Years says the product is tested in a registered laboratory, but the public sources reviewed did not name the lab or show an itemized test panel.

Is Leap Years vet-formulated?

Leap Years publicly names veterinarians and scientific figures, including the NC State trial investigator and veterinary leadership. That does not automatically prove a specific “vet-formulated” or “vet-approved” role for every formula claim.

Are Leap Years customer reviews enough to judge it?

No. Brand and retailer reviews are mostly useful for practical experience: whether dogs accept the chews, whether owners notice energy or mobility changes, and whether the price/routine feels worth repeating. Reddit discussion adds sharper caution because some owners report serious illness or tolerance concerns after use. Those comments do not prove causation, but they do make the unnamed actives and missing public COA more important to discuss with a veterinarian.

How does Leap Years compare with Hollywood Elixir?

Leap Years has the more direct published dog-study story for its proprietary LY-D2/LY-D6 system. Hollywood Elixir is relevant when a pet parent wants a more readable daily senior or longevity-support routine, not a duplicate of the Leap Years intervention.

What side effects have been reported with Leap Years?

Leap Years' own FAQ and product materials state that transient effects reported in under 1% of dogs include digestive upset, itchiness and neurological signs such as agitation, drowsiness or hind-leg weakness. Separately, some Reddit commenters describe alleged illness after use; those anecdotes are unverified and do not prove causation. For an older dog with pancreatitis history, kidney or liver disease, medications or recent cancer workups, discuss the product with your veterinarian before starting.

How much does Leap Years cost per month?

Based on the price snapshot checked on 2026-06-22: a 31-count jar at $54.99 one-time works out to about $53.22 per 30 days, the $52.24 Subscribe & Save listing to about $50.55, and the $69.99 listing to about $67.73 — assuming one jar covers 31 days for your dog's size. Recheck the current dog-size directions and renewal terms before relying on that math.

Who is Leap Years best for?

Leap Years best fits pet parents who value product-system dog evidence and are comfortable asking follow-up questions about unnamed actives, COAs and testing. It is less ideal for buyers who want every active compound, batch document and manufacturing detail visible before purchase.