When looking for GLP-1-related stocks to buy, investors are gravitating towards them New Nordisk AND Eli Lilly. This is because these two companies actually produce two of the most popular weight loss drugs today – Vega AND Mounjaroappropriately.

As the costs of these therapies decline and daily tablet versions are introduced to the market, the popularity of these drugs will boost rapidly. Actually, JP Morgan says more than 30 million Americans could operate them by 2030, up from 6.8 million in 2024.

In the UK, over 1.6 million adults are already using GLP-1. However, the total addressable market is much larger (3.4 million planned users via the NHS alone by 2036). Around two thirds of British adults are overweight.

There are several companies that I believe could see a gradual boost in sales thanks to this powerful long-term trend, including: Next (millions will need modern, smaller clothes). With that in mind, here are two UK stocks worth checking out.

Fitness

Naturally, losing weight can boost your confidence when it comes to hitting the gym. And that’s good news for The Gym Group (LSE:GYM), a leading low-cost operator with 923,000 members across 260 UK locations.

Last year revenues grew by 8% to £245m, with revenue from likes up 3%. Average monthly revenue per member increased by 4% to £21.60, indicating that prices can be raised without causing a mass exodus of members.

Adjusted pre-tax profit rose 194% to £10.6m. Meanwhile, the fitness company generated free cash flow of £38.3m, which funded the opening of all 16 modern facilities in 2025. With interest rates likely to rise again, I like this self-funded development.

Competition increases risk, as does the boost in electricity prices caused by the war in Iran. However, the group has just announced a £10m share buyout and plans to open a further 20 modern locations in 2026 (and 75 within three years). That’s why I think the positives can outweigh the negatives.

It is worth mentioning that strength training protects against the loss of muscle mass. Doctors prescribe such workouts and high-protein diets for GLP-1 users to prevent muscle wasting.

Finally, research group Mintel found that more than half of 18-24-year-olds went to the gym more than once in the month to July 2025, compared to 42% who went to the pub.

Nutrition and supplements

Many gym goers, of course, operate sports nutrition and health supplements. So a growing company with FTSE250 worth assessing Nutrition used (LSE:APN).

What I like about this ambitious company is its global reach (it operates in over 85 countries). For example, in the US there is a line of pre-workout drinks called ABE (All Black Everything). Walmart shops.

Its products are available in the UK TescoAsda and Holland & Barrett (where it sells its popular co-branded Coleen Rooney beauty and beauty range).

Revenues are expected to grow by around 30% to £140m in the current financial year (ending July), with powerful margins. This would mean an acceleration compared to last year.

One threat is rising ingredient cost inflation, with whey prices recently skyrocketing due to rising demand for protein. While this is not ideal specifically for products containing whey protein (about one-fifth of sales), raw materials beyond this ingredient are not volatile.

Interestingly, Morrisons is set to launch 53 food products under the Applied Nutrition brand, including high-protein snacks and GLP-1-friendly ready meals. The company’s shares are trading at just 17.7 times fiscal 27 forecast earnings.