For Youth vs IM8 vs AG1: Which Longevity Supplement Truly Delivers?

David Beckham recently launched IM8 , a lifestyle wellness brand promising to bring elite-level health to the public. His signature "Beckham Stack" bundles various supplements, including NAD+ boosters, astaxanthin, and others—positioning itself as a one-stop-shop for vitality, energy, and ageing support.

It's an exciting move; celebrities bring visibility to wellness trends, and NMN is certainly a hot topic. But when it comes to serious, research-driven longevity support, not all stacks are created equal.

The truth is, more ingredients don’t always mean better results. While IM8 and AG1 pack dozens of ingredients into their formulas, For Youth takes a targeted, science-backed approach, focusing on cellular health, longevity, and bioavailability. Instead of overwhelming the body with excessive micronutrients, For Youth’s Age Defence System zeroes in on NAD+ boosting, autophagy activation, and cellular protection—key pillars of anti-ageing and vitality.

Who really delivers when it comes to ageing better? Not all “longevity” supplements are built the same — and many aren’t even built for longevity at all.

In this article, we’ll compare all three side by side—focusing on ingredients, mechanisms, and scientific merit—to help you make an informed decision.

Below, we break down how For Youth’s Age Defence System stacks up against IM8 and AG1 — across science, ingredients, bioavailability, and long-term value.

For Youth is laser-focused on cellular ageing, combining NMN (450mg), Glutathione, and Spermidine — three clinically-researched ingredients targeting the root causes of biological decline: energy loss, oxidative stress, and cellular waste.

IM8 includes popular wellness actives like ashwagandha, quercetin, and astragalus — but quantities and combinations lack transparency. 

AG1 is a dense greens blend focused on broad-spectrum wellness, not cellular repair.

For Youth delivers 450mg of NMN — one of the highest daily doses on the market — plus clinical levels of glutathione and spermidine. No underdosing, no filler.

IM8 and AG1 spreads small doses across 75+ ingredients — making individual actives too weak to be impactful.

For Youth uses enzymatically-produced NMN, liposomal glutathione, and high-purity spermidine. Every batch is third-party tested, and test results are published online.

IM8 and AG1 use proprietary blends and undisclosed sources, which makes verification harder.

For Youth directly targets the three biggest drivers of ageing:

• Low NAD+ → via NMN
• Oxidative stress → via Glutathione
• Cellular waste accumulation → via Spermidine

This 3-step system supports energy, protection, and recovery — not just general wellness.

IM8 blends longevity-inspired ingredients, but lacks system structure or focus. 

AG1 supports broad health but doesn’t address longevity pathways like sirtuins or autophagy.

For Youth leverages liposomal glutathione, cofactor stacking, and synergistic delivery timing to boost absorption and results.

IM8 and AG1 are both powder blends — no mention of enhanced bioavailability.

For Youth was designed as a system — not a “stack.” Each product complements the next: NMN fills energy gaps, glutathione protects cells, and spermidine clears damage.

IM8 includes overlapping ingredients but unclear synergy. AG1 includes a wide range of ingredients without demonstrated synergy.

For Youth was formulated by leading longevity scientists from the National University of Singapore, including NAD+ and cellular ageing researchers. The product reflects current longevity science and best practices.

IM8 leans heavily on celebrity marketing and “biohacking” culture. AG1 offers general health support but little longevity-specific research.

For Youth is a 3-capsule daily ritual, designed for consistency and ease — no mixing, measuring, or grassy taste.

IM8 and AG1 both come as powders that require mixing, which can feel more like a chore than a ritual.

For Youth is vegan, non-GMO, third-party tested, and fully transparent about every ingredient and dosage.

IM8 and AG1 use proprietary blends, which can hide exact quantities of key ingredients.

While all three products sit at the premium end of the market, For Youth offers high clinical doses per dollar — especially for NAD+ support.

IM8 and AG1 offer “lifestyle stacks” with diluted actives — you pay for the blend, not the impact.

Where IM8 and AG1 try to cover everything with bloated blends and vague “wellness” claims, For Youth takes a targeted, science-led approach to cellular health and longevity.

• 450mg NMN (not sprinkled in)
• Liposomal glutathione to fight cellular stress
• Clinically-dosed spermidine to activate autophagy
• Formulated by real longevity scientists; not celebrity biohackers

This is not a greens powder. Not a pill drawer. Not a guess. It’s a clean, daily ritual that actually makes sense — and delivers results you can feel.

If you’re serious about aging well, the choice is clear.