Valtteri Bottas has opened up about the extreme and dangerous weight-loss diet he endured during his early days in Formula One, shedding light on the intense physical pressures drivers faced before modern regulations brought relief.

The 36-year-old Finn, now returning to the grid with the new American Cadillac team for the 2026 season, revealed he deliberately put himself through a near-starvation regimen during his second year with Williams—12 years ago. In a candid letter published by The Players' Tribune, Bottas admitted he felt "delusional" and "like a drug addict" as he chased a goal of shedding 10 kilograms, double what his team had originally suggested.

It all started when Williams predicted an overweight car for the 2014 season and asked Bottas to lose five kilos. "This was back when there was no seat-plus-driver weight minimum," he explained. "If you put a clear goal like that in front of me, I am going to obsess over it. When you tell me five kilos in two months, my brain thinks, 'Five? Why not 10? We can make the car even quicker.'"

What followed was a punishing cycle of steamed broccoli and cauliflower for nearly every meal, paired with double training sessions that pushed his body to the limit. "I can still smell the broccoli. Wet. Green. Plain. My god. It was like a game to me," Bottas recalled. "I would wake up and weigh myself every morning, and when I'd see the number go down, I'd feel a deep satisfaction."

To hide the extent of his obsession from his coach, Bottas would remove his GPS watch before second runs—knowing his trainer would see the burnout coming. "The game became completely consuming," he said.

For two months, Bottas pushed through the extreme diet, but the toll was severe. "My nerves were shot—I would wake up at 4am on my own, no alarm, my heart beating out of my chest." When pre-season testing finally arrived, the Williams car was actually underweight—a bitter irony that Bottas summed up with a wry: "Welcome to F1."

Only then did he begin to "feel weird" and suffer "intense foggy spells," a stark reminder of how far drivers once went for performance. Today, regulations require a combined minimum weight for driver and seat, ensuring no one has to risk their health for a competitive edge. Bottas's story is a powerful glimpse into a bygone era of the sport—and a testament to how far F1 has come in prioritizing driver well-being.