The Signal Buried Inside a Strong Quarter

Costco delivered one of its strongest quarters in recent memory. Net sales for the twelve weeks ending May 10, 2026 rose 11.6% to $69.15 billion, with net income climbing 15% to $2.19 billion. Comparable sales were up 9.8%. Digital channels surged 21.5%. By most measures, it was a clean beat across the board.

But buried within the earnings call was something more consequential than the headline numbers: management's explicit acknowledgment that GLP-1 drug adoption — the pharmaceutical trend that has put Ozempic and Wegovy on the cultural map — is now actively reshaping what Costco's members put in their carts, and how Kirkland Signature is being deployed in response.

This is not a passive category observation. It is a strategic merchandising decision confirmed by earnings data, and it carries direct implications for food brands, private label strategy, and the MENA food retail landscape.

What the Earnings Call Actually Said

During the Q3 analyst call, Costco CEO Ron Vachris was direct on the protein dynamic. Noting that "anything protein right now is doing extremely well," he cited protein snacks, protein bars, and beef sticks as standout categories — and confirmed that Costco had just launched its own Kirkland Signature Beef Stick, which was generating what he described as "tremendous volume."

CFO Gary Millerchip added further texture in his prepared remarks, noting that food and sundries comparable sales grew mid-single digits during the quarter, and that egg price deflation — a natural headwind — was being meaningfully offset by gains in protein snacks and protein bars. It was one of the few category-level call-outs in the entire earnings presentation.

Vachris also highlighted a second Kirkland protein launch: Kirkland Signature Ultra Filtered Protein Milk, placed in the dairy section, which he described as taking off "extremely, extremely strong." The framing on both launches was consistent: Costco is not waiting for brands to bring it higher-protein options. It is building them itself.

The GLP-1 Consumer: A New Purchasing Archetype

Understanding why Costco is making this bet requires understanding who the GLP-1 consumer is. This is not a fringe demographic. According to RAND Corporation data, approximately 12.4% of American adults had used GLP-1 medications for weight loss by mid-2025, more than double the rate from early 2024. Industry projections suggest GLP-1 sales could reach $100 billion globally by the end of the decade.

The behavioral profile of a GLP-1 user is distinctive and commercially significant. These consumers eat substantially less volume overall — GLP-1 medications suppress appetite — but they become acutely focused on nutritional return per bite. Research from Lumina Intelligence characterizes the typical GLP-1 user as young, affluent, and highly health-conscious, noting that in the UK, roughly 95% have household incomes above £100,000. They work out more than the general population, actively seek high-protein options, and describe themselves as "very health-driven."

Crucially, GLP-1 users face a clinical incentive to prioritize protein: the medications are associated with a 25–40% reduction in muscle mass over eight to sixteen months, several times greater than muscle loss observed in non-medicated weight loss. That creates a genuine metabolic need — not just a preference — for high-protein intake among this cohort. Some 73% of GLP-1 users report actively trying to consume more protein, compared with 65% of Gen Z and Millennials broadly.

Kirkland as a Category Weapon

The strategic logic of Costco's response is straightforward, but its competitive implications are not. Kirkland Signature is not a defensive private label program designed to offer a cheaper alternative to national brands. It is an offensive tool, built to capture category margin and member loyalty simultaneously — and its pricing guarantee (at least 15–20% below the national brand equivalent at equal or better quality) means it competes on both value and product credentials.

When Costco launches a Kirkland Beef Stick or a Kirkland Ultra Filtered Protein Milk in direct response to observed member demand signals, it is not offering a commodity substitute. It is building a proprietary stake in the fastest-growing segment of the food and sundries category — and doing so at a scale that immediately threatens the shelf position of any brand that hasn't reformulated to compete on protein density and clean ingredient decks.

For CPG suppliers in these segments, the risk is not primarily that Costco will delist their SKUs. It is that Costco will define the category benchmark on their behalf. A national brand beef stick that sits next to a Kirkland Signature version offering more protein per serving at a lower price point is not simply competing — it is being measured against a standard it may not meet.

The Broader Convergence: Protein Meets Clean Label

What Costco's Q3 data confirms is something that market analysts have been tracking for over a year: protein and clean-label have converged into a single purchasing criterion for a growing and commercially powerful consumer segment. The GLP-1 cohort wants protein, but it also wants transparency, fewer ultra-processed ingredients, and products that can be consumed in smaller portions without sacrificing nutritional payoff.

This creates a specific product architecture that winners in the category are converging on: high protein density, minimal ingredient lists, functional nutrient additions (fiber, magnesium, electrolytes), and a format that works in smaller servings. The categories best positioned to benefit are protein bars, refrigerated snacks, ready-to-eat meals, ultra-filtered dairy, and high-protein prepared foods — all of which happen to be areas where Kirkland is now actively expanding.

Brands that have not begun reformulating toward this architecture are not simply behind a trend. According to the analytical framework tracking this convergence, they are building a displacement risk — a scenario where their shelf position is progressively occupied by private label alternatives that better match evolving member demand.

Implications for MENA Food Manufacturers and Retailers

The GLP-1 phenomenon is primarily a Western market dynamic for now — but its structural implications are increasingly relevant for food producers and retailers across Saudi Arabia and the MENA region, and for two distinct reasons.

First, the export and positioning risk for MENA-produced food products targeting Western retail channels. Producers supplying protein snacks, dairy, or packaged food categories to European or North American retailers need to understand the Kirkland benchmark effect: Costco and its peers are defining a new category floor for protein content and ingredient quality. Meeting that standard is no longer optional for shelf longevity.

Second, the GLP-1 behavioral profile — health-conscious, protein-focused, nutrient-density-driven, affluent — closely mirrors the consumer segment that Saudi Arabia's Vision 2030 food strategy is targeting as it builds out domestic premium food production capacity. The Saudi consumer base is skewing younger, more health-aware, and more demanding of functional nutrition credentials. Retailers and food brands operating in the Kingdom should view the Costco data point as a directional signal, not a distant foreign market story.

The protein snack, high-protein dairy, and functional RTD categories are all underserved in the GCC relative to Western markets. The convergence of health-aware affluent consumers, GLP-1 drug adoption as a global trend (prescription volumes are rising across the Gulf), and Vision 2030's domestic food manufacturing push creates a meaningful investment and product development window for brands that move early.

Editorial View

The Costco Q3 earnings call was not primarily a story about protein. It was a story about a retailer of uncommon scale using behavioral data to make a decisive private label bet — and confirming, through the weight of actual quarterly results, that the GLP-1 cohort has crossed a threshold from trend to structural market force.

For investors and operators in the food sector, the read-through is clear. The brands that will hold shelf position in the protein category are those that have reformulated for density, cleaned up their ingredient decks, and built products that serve a consumer who eats less but demands more. Those that haven't started that process are not watching a trend from a distance — they are already in the shadow of a Kirkland SKU.

And for those tracking the MENA food landscape: Costco's GLP-1 protein pivot is a preview. Consumer health behavior is globalizing faster than most food producers have built their product pipelines to accommodate.