David Sinclair NMN Brand: What He Actually Takes, His Full 2026 Protocol, and How to Replicate It

Who Is David Sinclair and Why Does His NMN Protocol Matter?

David Sinclair, PhD, AO, is a professor of genetics at Harvard Medical School, co-director of the Paul F. Glenn Center for Biology of Aging Research, and the author of the 2019 bestseller Lifespan: Why We Age, and Why We Don't Have To. He is arguably the most publicly visible longevity researcher in the world, and his personal supplement protocol has become the de facto template for consumer NAD+ supplementation.

Sinclair's influence on the NMN market is difficult to overstate. Before Lifespan was published, NMN was a niche research compound known primarily to scientists studying NAD+ metabolism. After the book, NMN became a mainstream supplement category generating hundreds of millions of dollars in annual sales. Sinclair did not create NMN, does not sell it, and does not endorse any brand, but his public discussion of taking it every morning made him the single most effective marketing force the NMN industry has ever had.

This creates a peculiar consumer situation: millions of people want to buy "the NMN David Sinclair takes," but Sinclair has never named a brand. He has discussed the molecule, the dose (1 g/day), the co-factors (resveratrol taken with fat), and the reasoning (NAD+ replenishment activates sirtuins). He has not said "I buy from Brand X." Every product marketed as "Sinclair's choice" or "the NMN Sinclair recommends" is making that claim without his authorization.

What you can do is match his publicly described protocol (molecule, dose, purity standard, and co-factors) using any NMN product that meets quality criteria. That is what this article helps you do.

Sinclair's Complete 2026 Supplement Protocol (Verified Sources)

Based on Sinclair's book, podcast interviews, and his 2025-2026 public updates (including a June 2025 interview with Peter Diamandis at the Abundance Summit), his current protocol includes NMN 1 g, resveratrol 1 g, berberine (replacing metformin), fisetin 500 mg, quercetin 500 mg, spermidine 1-2 mg, vitamin D3, vitamin K2, omega-3s, low-dose aspirin, and a statin: the last two being prescription medications for his specific genetic cardiovascular risk.

The most significant protocol change in 2025-2026 was Sinclair's switch from metformin to berberine. In his interview with Peter Diamandis, Sinclair explained that metformin was "hard on his stomach": a common GI side effect of the drug. Berberine activates AMPK through a similar mechanism and has its own body of published evidence for blood sugar management. For the complete berberine evidence review, see our What Is Berberine? guide and berberine vs metformin comparison.

Sinclair's Research: What His Lab Has Actually Proven

Sinclair's lab at Harvard has published over 200 peer-reviewed papers on aging biology, including foundational work on sirtuins, NAD+ metabolism, and the Information Theory of Aging. His most cited contributions include demonstrating that resveratrol extends lifespan in mice on high-fat diets (Baur et al., 2006; PMID 17086191), showing that NMN reverses age-related arterial dysfunction in mice (de Picciotto et al., 2016; PMID 26970090), and proposing that epigenetic noise (loss of information in gene regulation) is a primary driver of aging.

Understanding what Sinclair has and has not proven is essential for evaluating his protocol objectively. His lab's work on sirtuin biology established that these enzymes play a central role in cellular stress responses and that their activity declines with age as NAD+ levels fall. This is foundational science that has been replicated by multiple independent labs worldwide and is broadly accepted in the aging research community.

Where the evidence becomes more contested is the translation from animal models to human interventions. Resveratrol's ability to extend lifespan in mice on high-fat diets did not replicate consistently across all studies, and the doses used in mice (when scaled to humans) are far higher than typical supplement doses. NMN's reversal of vascular aging in mice is promising but has not been confirmed in human vascular studies. The Information Theory of Aging (Sinclair's most ambitious thesis) is a framework for understanding why aging happens, not a prescription for what to take.

Sinclair is transparent about the distinction between his research findings and his personal protocol. In interviews, he regularly notes that his supplement stack is a personal experiment informed by his research, not a clinical recommendation. "I'm not telling anyone what to take," he has said in multiple podcast appearances. "I'm telling you what I do, and I'm sharing the science behind why." This intellectual honesty is worth acknowledging, because many people who follow his protocol treat it as a prescription rather than an educated personal experiment.

The practical takeaway: Sinclair's scientific credibility gives his protocol more intellectual weight than random internet longevity stacks. But his protocol is not a proven clinical intervention. It is the supplement regimen of a brilliant researcher who is betting on his own science, and inviting you to understand the bet before you make it yourself.

The NMN + Resveratrol Logic: Why Sinclair Takes Both Together

Sinclair's core thesis is that NMN and resveratrol work combinedally: NMN provides the NAD+ fuel that sirtuins need to function, while resveratrol activates those sirtuins. Without sufficient NAD+ (fuel), sirtuin activation (resveratrol) has less substrate to work with. Without sirtuin activation (resveratrol), raised NAD+ may not be optimally directed toward longevity-relevant pathways. Together, they address both sides of the equation.

This is the theoretical basis for the "Sinclair Stack" (NMN + resveratrol) that has become the most widely replicated longevity supplement protocol among consumers. The logic is biochemically sound: sirtuins are NAD+-dependent enzymes, and both NAD+ levels and sirtuin activity decline with age. Addressing both simultaneously makes mechanistic sense.

The critical caveat: this combined effect has been demonstrated in animal models but not conclusively in human clinical trials. Sinclair's own lab has published extensively on sirtuin biology and NAD+ metabolism in mice and yeast, but the human translation (the part that actually matters to you) remains in early stages. The Yoshino et al. (2021; PMID 33888596) trial showed NMN improved muscle insulin sensitivity in pre-diabetic women, which is one of the stronger clinical outcomes from any NAD+ precursor trial. But no published trial has tested the NMN + resveratrol combination specifically.

Sinclair explicitly takes resveratrol with fat (mixed into yogurt or avocado) because resveratrol is poorly absorbed without a fat matrix. This is not a minor detail, bioavailability of resveratrol without fat is extremely low, and many people taking it as a dry capsule on an empty stomach are wasting most of their dose. For the full NMN + resveratrol evidence review, see our NMN and resveratrol guide.

What NMN Brand Does Sinclair Take? (The Honest Answer)

David Sinclair has not publicly confirmed any specific consumer NMN brand. He has discussed the molecule, the dose, and the science, but not the brand name on his bottle. Any product claiming to be "Sinclair's NMN," "Sinclair-approved," or "the brand Harvard's longevity researcher recommends" is fabricating that association. This includes both direct claims and implied endorsements through carefully worded marketing.

This is worth emphasizing because it is one of the most common deceptions in NMN marketing. A search for "David Sinclair NMN brand" returns dozens of articles that ultimately recommend a specific product, each claiming or implying that their recommended brand is what Sinclair uses. None of them can verify this claim because Sinclair has not made the information public.

What Sinclair has shared (and what actually helps you make a purchasing decision) is the criteria that matter for any NMN product:

Dose: Sinclair takes 1,000 mg/day. This matches the higher end of published clinical trial doses and the dose at which NR produced 142% NAD+ elevation in the Conze et al. NR dose-response trial (at equivalent doses, NR and NMN produce comparable NAD+ increases). Most consumer NMN products offer 250-500 mg per capsule, so reaching 1,000 mg typically requires 2-4 capsules daily.

Purity: Sinclair's lab works with pharmaceutical-grade NMN. For consumer products, look for brands that publish third-party Certificates of Analysis (COAs) showing NMN purity at 98%+ by HPLC testing, with heavy metal screening and microbial testing. See our NMN COA verification checklist for exactly what to look for on a COA.

Stability: NMN can degrade with heat and moisture. Products using moisture-barrier packaging, desiccants, or recommending refrigeration demonstrate awareness of stability requirements. Powder NMN in a simple jar without moisture protection is a red flag.

No unnecessary additives: Sinclair's protocol is molecule-specific. He is not looking for a proprietary blend with 20 ingredients at unknown doses. He takes specific molecules at specific doses. A good NMN product mirrors this philosophy: NMN at a stated dose, minimal excipients, full transparency.

For NMN products that meet these criteria with independently verified purity data, see our NMN supplement guide. For brand-specific reviews including purity verification, see our reviews of Wonderfeel, ProHealth, Cymbiotika, and Omre.

Red Flags: How to Spot Fake "Sinclair-Endorsed" NMN Products

The NMN market is flooded with products that exploit Sinclair's name for marketing. Because Sinclair has never named a brand, any product claiming his endorsement is misleading. Recognizing these tactics protects both your money and your health, because brands willing to fabricate celebrity associations are often willing to cut corners on product quality as well.

Red flag #1: "As recommended by David Sinclair" or similar phrasing on the product page or advertising. Sinclair does not endorse consumer NMN products. He has no sponsorship deals, affiliate codes, or brand partnerships for NMN. If a brand implies his recommendation, they are fabricating it.

Red flag #2: Articles titled "David Sinclair's NMN Brand Revealed" that end with an affiliate link to a specific product. These are content marketing pieces designed to rank for the "David Sinclair NMN brand" keyword and monetize it through affiliate commissions. The product they recommend is whoever pays them the highest commission, not what Sinclair actually uses.

Red flag #3: Products using Sinclair's image, quotes, or Harvard affiliation in their marketing materials without attribution to a verifiable source. Using a public figure's image to sell a product without their consent is legally actionable and ethically clear, it is a signal that the brand's marketing ethics are low, which correlates with low product quality standards.

Red flag #4: NMN products with proprietary blends that do not disclose the actual NMN dose. Sinclair takes a specific, known dose, 1,000 mg. If a product hides its NMN content behind a "proprietary blend" label, you cannot verify that you are getting a meaningful dose. Sinclair's protocol is built on dose specificity; products that obscure their doses contradict its fundamental principle.

What to look for instead: Third-party COAs showing NMN purity at 98%+ (published on the brand's website or available on request), clearly stated NMN dose per capsule on the Supplement Facts panel, no proprietary blends, and no Sinclair endorsement claims. The product that best matches Sinclair's protocol is whichever one delivers verified-purity NMN at your target dose for the best price, nothing else matters. Our NMN COA verification checklist walks through exactly how to read a Certificate of Analysis.

The Simplified Sinclair Stack: A Budget-Friendly Starting Point

Not everyone can or should spend $200+/month on the full Sinclair protocol. A simplified version focusing on the two core components (NMN and resveratrol) captures the primary mechanism (NAD+ replenishment + sirtuin activation) at $50-$80/month. Adding fisetin and quercetin as a secondary layer brings the cost to $80-$120/month. The remaining components (spermidine, vitamin D3+K2, omega-3) are standard health supplements most people should consider regardless of longevity goals.

Tier 1: The Core ($50-$80/month): NMN 500 mg/day + resveratrol 500 mg/day (taken with fat). This covers the primary NAD+ precursor and sirtuin activator at doses with published human data. Half of Sinclair's dose, but still within clinically studied ranges. See our NMN dosage guide for dose selection rationale.

Tier 2, Add Senolytics ($80-$120/month): Add fisetin 500 mg and quercetin 500 mg for senescent cell clearance. Some practitioners recommend intermittent "senolytic courses" (high-dose fisetin + quercetin for 2-3 days per month) rather than daily low-dose use, based on how senolytics were used in the Hickson et al. Clinical trial.

Tier 3, Full Protocol ($150-$300/month): Add spermidine for autophagy, TMG for methylation support, and ensure foundational nutrients (vitamin D3, K2, omega-3, magnesium) are covered. At this level, annual blood panels ($200-$400/year) become important to verify that the stack is producing measurable changes in relevant biomarkers, NAD+ levels, inflammatory markers, metabolic panel, homocysteine.

For the complete supplement stacking guide with interaction warnings, see our supplement stacking guide and supplements not to take together guide.

Building the Sinclair Protocol: Cost and Sourcing

The full Sinclair supplement stack (excluding prescription medications) costs approximately $150-$350/month depending on brand choices and sourcing. The two largest cost items are NMN ($30-$90/month at 1,000 mg/day) and resveratrol ($20-$50/month at 1,000 mg). Buying combined products (like NMN + resveratrol formulas) can reduce cost but may compromise dose flexibility.

Component	Sinclair Dose	Budget Sourcing	Premium Sourcing
NMN 1,000 mg/day	1 g	$30-$45/mo (bulk powder)	$60-$90/mo (branded capsules)
Resveratrol 1,000 mg/day	1 g (with fat)	$15-$25/mo (trans-resveratrol)	$30-$50/mo (micronized)
Fisetin 500 mg	500 mg	$15-$20/mo	$25-$35/mo
Quercetin 500 mg	500 mg	$10-$15/mo	$20-$30/mo (phytosome)
Spermidine 1-2 mg	1-2 mg	$25-$40/mo	$40-$60/mo
Vitamin D3 + K2	~4,000 IU	$5-$10/mo	$10-$15/mo
Omega-3 (EPA/DHA)	1-2 g	$10-$15/mo	$25-$40/mo
TMG (methylation support)	~500 mg	$5-$10/mo	$10-$15/mo
TOTAL OTC STACK		$115-$180/mo	$220-$335/mo

Some important notes on cost optimization: the NMN + resveratrol combination is available in single products (like Omre NMN + Resveratrol at 500 mg NMN + 500 mg resveratrol per serving), which simplifies the stack but provides half the dose Sinclair describes. Two servings would match his dose at approximately $60-$70/month for those two compounds combined.

The budget-to-premium range is wide because NMN quality varies significantly across brands. Our NMN supplement guide covers how to identify products with verified purity at different price points, and our NMN delivery format comparison explains the trade-offs between powder (cheapest per mg), capsules (most convenient), and sublingual (fastest absorption).

What Sinclair's Protocol Gets Right (and What It Does Not Address)

Sinclair's protocol is a well-reasoned, multi-pathway approach to longevity supplementation that targets NAD+ replenishment, sirtuin activation, senescent cell clearance, autophagy induction, and metabolic optimization simultaneously. It is among the most scientifically literate consumer supplement protocols in existence. What it does not address (and what Sinclair would likely be the first to acknowledge) is that no supplement stack has been proven to extend human lifespan.

What the protocol gets right:

• Each component targets a distinct, evidence-backed aging mechanism rather than overlapping redundantly
• Doses are specific and at or near levels used in published research, not arbitrary "fairy dust" amounts
• The NMN + resveratrol combination addresses both NAD+ supply and sirtuin demand simultaneously
• Taking resveratrol with fat optimizes bioavailability: a detail many protocols miss
• The switch from metformin to berberine reflects practical tolerability without abandoning the AMPK activation goal
• TMG as methylation support addresses a real biochemical consequence of NAD+ supplementation

What the protocol does not prove:

• That this specific combination extends human lifespan, no supplement protocol has demonstrated this
• That you need all components simultaneously: the marginal benefit of component #7 over components #1-6 is unknown
• That Sinclair's dose is optimal for you, his 1,000 mg NMN reflects his personal risk tolerance and budget; clinical trials have shown meaningful NAD+ elevation at 250-500 mg as well
• That supplements matter more than the basics. Sinclair also practices intermittent fasting, high-intensity exercise 3-4 times/week, sauna exposure, cold therapy, and regular blood testing; these lifestyle factors likely contribute more to his biological age than any supplement

The lifestyle components are often underweighted in discussions of the Sinclair Protocol because they do not generate affiliate commissions. Nobody earns a referral fee when you go for a run or get eight hours of sleep. But the evidence hierarchy is clear: exercise has more published human data supporting longevity benefit than any supplement. A 2022 meta-analysis in the British Journal of Sports Medicine found that 150 minutes of moderate exercise per week reduced all-cause mortality by 31% and cardiovascular mortality by 29%. No supplement (NMN, resveratrol, or otherwise) has comparable human outcomes data.

This does not make supplements worthless. It contextualizes them. The Sinclair Protocol is best understood as optimizations layered on top of a foundation of exercise, sleep, diet, and stress management: not as a replacement for those foundations. If you are choosing between spending $100/month on NMN or spending $50/month on a gym membership plus $50 on NMN at a lower dose, the gym membership plus lower-dose NMN is almost certainly the higher-impact choice.

Sinclair himself emphasizes this hierarchy. In multiple interviews, he has stated that exercise, diet, and sleep are the foundation, and supplements are additions to (not replacements for) those behaviors. A $300/month supplement stack on top of a sedentary lifestyle with poor sleep and a processed food diet will produce far less benefit than good sleep, regular exercise, and $30/month of NMN.

Sinclair's Critics: What the Scientific Community Debates

Sinclair is not without scientific critics. The most common criticisms center on the replicability of resveratrol lifespan extension studies (some labs failed to replicate the original results), the gap between mouse and human data for NMN, Sinclair's commercial interests in longevity companies, and the broader concern that his public profile may lead consumers to overestimate the certainty of longevity supplement benefits.

On resveratrol: the original 2006 study (Baur et al.) showing lifespan extension in mice on high-fat diets was groundbreaking, but subsequent attempts to replicate in normal-weight mice produced mixed results. Some researchers argue that resveratrol primarily helps metabolically unhealthy organisms rather than providing universal anti-aging benefits. Sinclair has responded that the disagreement is about the scope of benefit, not whether sirtuins matter, and that his more recent focus on NAD+ (rather than resveratrol alone) reflects this evolution in understanding.

On commercial interests: Sinclair has disclosed financial relationships with companies in the longevity space, including MetroBiotech (an NAD+ therapeutics company) and InsideTracker (a biomarker testing company). These are standard academic-industry relationships, disclosed in his publications and public statements, but they are worth noting because they create potential bias toward NAD+-positive narratives. This does not invalidate his research (it was peer-reviewed and published in top journals) but it is context you should have when evaluating his protocol recommendations.

On the mouse-to-human translation gap: this is the most scientifically legitimate criticism. NAD+ replenishment produces dramatic results in aging mice, improved mitochondrial function, better insulin sensitivity, enhanced exercise capacity, even some evidence of lifespan extension. In humans, NAD+ reliably goes up with NMN supplementation, but clinical health improvements have been modest and inconsistent across trials. The multi-billion-dollar NAD+ supplement industry is built primarily on animal data and the assumption that human results will follow. They may, but they have not yet, at the scale and consistency the animal data would predict.

None of this means Sinclair's protocol is wrong. It means it is an educated bet on emerging science, not a proven clinical intervention. Sinclair himself frames it this way. The problem is not Sinclair's communication, it is how his protocol gets distorted through layers of marketing, affiliate content, and social media telephone-game into certainties it does not support.

NMN Dose: Do You Need Sinclair's Full 1,000 mg?

Published clinical trials show meaningful NAD+ elevation at doses as low as 250 mg/day. The Conze et al. Dose-response data (using NR, which produces comparable NAD+ changes) showed 22% NAD+ increase at 100 mg, 51% at 300 mg, and 142% at 1,000 mg. The dose-response is not linear, most of the benefit comes in the first 300-500 mg, with diminishing returns above that. Whether 142% NAD+ elevation produces meaningfully better health outcomes than 51% is unknown.

The dose-response curve for NAD+ elevation is sublinear, meaning the jump from 0 to 300 mg produces more benefit per milligram than the jump from 300 to 1,000 mg. Conze et al. Showed that going from 0 to 100 mg raised NAD+ by 22%, adding another 200 mg (to 300 mg total) raised it to 51%, and adding another 700 mg (to 1,000 mg total) raised it to 142%. The first 300 mg delivered 51% of the 142% maximum (roughly 36% of the full benefit per milligram) while the next 700 mg delivered the remaining 91 percentage points at less than half the per-milligram efficiency.

This has practical implications for cost-conscious consumers. If NMN at 300-500 mg/day costs $20-$35/month and delivers 50-80% of the NAD+ elevation that 1,000 mg provides at $60-$90/month, the lower dose represents substantially better value per percentage point of NAD+ increase. Sinclair, as a Harvard professor with above-average income and a deep personal investment in longevity research, can justify the premium dose. Most consumers may find the mid-range dose sufficient.

For most people starting NMN supplementation, 250-500 mg/day is a reasonable and cost-effective dose. This range has published human trial support (Yoshino et al. Used 250 mg in pre-diabetic women; multiple trials have used 500-900 mg), keeps monthly cost manageable ($15-$40/month), and provides substantial NAD+ elevation. Escalating to 1,000 mg is reasonable for people who have taken 500 mg for several months, can afford the cost increase, and want to match the highest-studied dose tier. For detailed dosing guidance, see our NMN dosage guide.

Who Benefits Most From Following the Sinclair Protocol?

The Sinclair Protocol is best suited for people over 40 who have already optimized their lifestyle foundations (exercise, sleep, diet), have budget capacity for $100-$300/month in supplements, are comfortable with emerging-but-incomplete evidence, and approach supplementation as an informed experiment with regular biomarker monitoring: not as a set-and-forget routine.

People under 35 are unlikely to benefit significantly from NAD+ supplementation because their NAD+ levels have not yet declined substantially. The Conze et al. Trial enrolled "healthy overweight adults" aged 55-75, and the NADPARK trial enrolled Parkinson's patients with a mean age of 63. The clinical context for NAD+ precursors is aging populations with declining NAD+: not young healthy adults with normal levels. If you are 28 and considering the Sinclair stack, your money is almost certainly better spent on a gym membership, quality food, and sleep optimization.

People over 45 with metabolic concerns (rising fasting glucose, declining energy, early signs of cognitive fog) represent the sweet spot for this protocol. NAD+ decline is measurable by this age, the mechanistic rationale is strongest, and the co-factors in Sinclair's stack (berberine for blood sugar, resveratrol for cardiovascular protection, fisetin for senescent cell clearance) align with common midlife health concerns.

People over 65 can benefit but should exercise more caution with dose and drug interactions. Multiple components in the Sinclair stack (berberine, quercetin, resveratrol) interact with common medications prescribed to older adults (statins, blood thinners, diabetes drugs). A conversation with a prescriber who understands longevity pharmacology is essential before building a complex stack in this age group. For specific interaction warnings, see our supplements not to take together guide.

Frequently Asked Questions

What brand of NMN does David Sinclair take?

Sinclair has not publicly confirmed any specific consumer NMN brand. He discusses the molecule (NMN), the dose (1 gram), and the co-factors (resveratrol with fat), but not the brand name. Any product claiming to be "Sinclair-approved" or "the NMN David Sinclair takes" cannot verify that claim. Choose NMN based on purity verification (third-party COA), dose, and price rather than unverified celebrity association.

Why does Sinclair prefer NMN over NR?

Sinclair has stated in interviews that unpublished research from his lab showed NMN improved endurance in mice by 50% while NR did not show the same benefit. He also considers NMN one step closer to NAD+ in the metabolic pathway. However, the first direct human comparison trial found both precursors produce comparable NAD+ elevation. The NMN vs NR debate remains unresolved at the clinical level. See our NMN vs NR comparison for the complete evidence.

How much does the Sinclair supplement stack cost?

The complete OTC supplement stack (NMN, resveratrol, fisetin, quercetin, spermidine, vitamin D3+K2, omega-3, TMG) costs approximately $150-$350/month depending on brand choices. The two largest cost drivers are NMN ($30-$90/month) and spermidine ($25-$60/month). A simplified version focusing on just NMN + resveratrol + a multivitamin runs $50-$100/month.

Why did Sinclair switch from metformin to berberine?

In his June 2025 interview with Peter Diamandis, Sinclair explained that metformin caused GI side effects. Berberine activates AMPK through a similar mechanism and has published evidence for blood sugar management. Both are used as AMPK activators in longevity protocols. For the comparison, see our berberine vs metformin guide.

Should I copy Sinclair's exact protocol?

No, and Sinclair himself says this. His protocol is his personal experiment based on his specific genetics, health markers, and research knowledge. His statin and aspirin are prescribed for his genetically raised cardiovascular risk, which you may not share. His NMN dose reflects his risk tolerance and budget. Start with the foundational components (NMN at 250-500 mg, resveratrol if budget allows, vitamin D3), and build from there based on your own blood work and healthcare provider guidance.

Is 1,000 mg of NMN safe?

Published human trials at NMN doses up to 1,250 mg/day have reported no serious adverse events. Common mild effects include GI discomfort and headache at low incidence. The safety record is good but based on trials lasting weeks to months, not decades. For the complete safety review, see our NMN side effects guide.

Why does Sinclair take resveratrol with yogurt?

Resveratrol is fat-soluble and has very poor oral bioavailability when taken without fat. Mixing it with yogurt (which contains fat) or avocado dramatically improves absorption. This is one of the most commonly missed details in resveratrol supplementation, taking it as a dry capsule on an empty stomach likely wastes most of the dose. See our NMN and resveratrol guide for absorption optimization.

What about Sinclair's lifestyle beyond supplements?

Sinclair practices intermittent fasting (often skipping breakfast and lunch), runs 1-2 times per week at high intensity, boxes and lifts weights 2-3 times per week, uses sauna exposure with cold plunge, prioritizes sleep, and monitors his biomarkers through regular blood work. He has stated repeatedly that these lifestyle factors likely contribute more to his biological age than his supplement stack.