Last week I wrote about how eating less meat was the best way to reduce your food’s carbon footprint. But what do you do if you want to be a responsible corporate citizen and you sell fast food? Well, I think your company would look a lot like Max Burgers, based in Sweden.

I recently spoke to Richard Bergfors, the CEO (and son of the founders) of this unusual 44-year-old “fast” food chain. With 3000 employees and about $200 million in revenue, Max Burgers is a great example of how a midsize company can carve out a profitable niche through a focus on sustainability — even in an unexpected sector.

In 2000, the company set a new strategy focused on the word “fresh.” The leaders looked closely at every ingredient and reduced fat, salt, and sugar, and eliminated genetically modified organisms (GMOs) and trans fats. The menu got healthier, with multiple side options besides fries, 10 drinks with no added sugar, and a selection of darker, healthier breads. The company now sources 100% of its beef and chicken — and 90% of all its product — locally.

To explore its broader climate impact, the firm started working with Swedish thought leaders Natural Step, which, not surprisingly, identified beef as the biggest problem for the company (80 to 85 percent of the footprint). Bergfors acknowledges that industry-wide climate-friendly beef is still a long way off, so Max Burgers plants trees in Africa to offset its carbon footprint. New stores also use solar panels for 15 to 20 percent of electric needs.

But perhaps the most surprising thing this company does is try to influence its customers to buy less meat. Quick reminder: the chain is called Max Burgers. This counterintuitive strategy is the kind of heresy I love — asking customers to use less of your core product. Max Burgers accomplishes this by adding more non-meat items to the menu, prominently displaying climate footprint data in store (there’s transparency for you), and suggesting customers buy chicken, fish, or veggie sandwiches periodically (a là Meatless Mondays).

In 2004, a golden marketing opportunity came along with the launch of the documentary Supersize Me, which followed director Morgan Spurlock as he ate only McDonald’s food for 30 days. Max Burgers decided to launch a tongue-in-cheek “Minimize Me” campaign. A customer, much like Subway’s famous Jared, ate only Max Burgers for 90 days and lost 77 pounds. Two years later, the company re-ran the promotion with multiple people competing on the Max-only diet.

The result of all these efforts is a more sustainable burger chain that’s telling everyone to eat less meat, and doing so profitably. The mix of non-beef products is 30% higher than it used to be. But the profit margins are very high.

Bergfors reports that his stores are averaging 11 to 15 percent profit margins versus 2 to 5 percent at the big name competitors. He says Max Burgers is the most profitable, fastest growing chain in Sweden, expanding at 20% per year (and 5% same store sales growth) in a flat market. Granted, higher-end niche brands generally do have higher margins, but this is not an overly small company, and it doesn’t seem to be sacrificing anything with its “minimize me” strategy — quite the contrary.

Of course a family run company always has more leeway to act on values (see Patagonia, the prime example). As Bergfors told me, “we’ve always done things a bit differently — the goal is greater than to just maximize profit.” But it’s still a business, and in the next breath he said, “we’re profit driven and like to make a profit like everyone else…but we don’t put profit first…we don’t have to maximize profit and we can care for people and the planet we’re living on.”

But given Max Burgers’ profit levels, it seems that maximizing all value, not just profits, can be darn good business.