President Trump Loaded Up on Eli Lilly in Q1. Should You Buy the Obesity Drug Stock Too?

President Donald Trump's recent financial disclosures revealed thousands of stock transactions for dozens of companies in the first quarter of 2026, including Eli Lilly (NYSE: LLY), one of the biggest winners in the anti-obesity drug boom.

The president's stock transactions (or, more likely, transactions made by others on his behalf) may grab headlines, but investors should be careful about copying any politician's trades, particularly after the fact. You should buy stocks based on the attractiveness of the underlying business, not because a public official or celebrity happens to own shares.

That said, in the case of Eli Lilly, the arguments for ownership remain compelling.

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An eventual $200 billion market is up for grabs

Eli Lilly generated roughly $65 billion in revenue during 2025, driven largely by explosive demand for its diabetes and obesity treatments Mounjaro and Zepbound. Combined sales of those two products exceeded $30 billion last year, making them among the fastest-growing drugs in pharmaceutical history.

And the weight-management opportunity still appears to be in its early stages. Analysts at J.P. Morgan and Goldman Sachs have projected that the global market for anti-obesity drugs could eventually exceed $95 billion annually, with some estimates approaching $200 billion over the next decade.

Eli Lilly and Novo Nordisk (NYSE: NVO) currently dominate that market, but Lilly's growth trajectory has recently been stronger as its manufacturing capacity expands and Zepbound continues gaining market share. Lilly is also investing heavily to maintain its lead.

What about Eli Lilly's valuation?

Eli Lilly has committed tens of billions of dollars to expanding manufacturing capacity while advancing next-generation obesity treatments designed to improve efficacy, convenience, and long-term weight maintenance.

Its financial results reflect that momentum. Analysts currently expect Lilly to generate annual earnings of roughly $37 to $52 per share over the next four years (it was $23 per share in 2025) as obesity-treatment revenue continues to scale up. Its revenue is expected to grow significantly faster than that of most large pharmaceutical peers, helping to justify a premium valuation.

Risks and rewards

That valuation, of course, is the primary risk. Eli Lilly stock trades at a substantially higher earnings multiple than most large-cap pharmaceutical companies. Investors buying today will be getting a stock with years of future growth already priced in. If sales growth slows, competition intensifies, or manufacturing challenges emerge, the stock will see significant volatility.

Competition is also increasing. Novo Nordisk continues to expand its anti-obesity franchise, while pharma companies including Viking Therapeutics, Structure Therapeutics, Amgen, Roche Holding, and several other large pharmaceutical firms are developing next-generation obesity treatments.

Still, Lilly remains the current leader. It has one of the strongest weight-management franchises in the industry, substantial manufacturing advantages, a deep pipeline, and the financial resources to defend its position.

So, should you buy stock in Eli Lilly because President Trump bought shares? No.

But if you believe obesity therapies will become one of the largest pharmaceutical markets in history, Eli Lilly remains one of the most direct ways to invest in that trend.

JPMorgan Chase is an advertising partner of Motley Fool Money. Jeff Siegel has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Amgen, Eli Lilly, Goldman Sachs Group, and JPMorgan Chase. The Motley Fool recommends Novo Nordisk, Roche Holding AG, and Viking Therapeutics. The Motley Fool has a disclosure policy.