(CNN)Lewis Hamilton estimated he lost "around three kilos" during the French Grand Prix after a drinks bottle malfunction left him unable to rehydrate.
On a sweltering Sunday afternoon at the Circuit Paul Ricard, the seven-time world champion recorded his best finish of the season by coming second behind Red Bull's Max Verstappen.
Despite the bottle issue, Hamilton said he felt "fantastic" after the race.
"I was just a little bit dehydrated," he told reporters, per F1. "The drinks bottle didn't work in the race. I don't actually ever drink in the race ever, so this is the first time I actually tried it all year and there was nothing coming out.
"I didn't see my weight just now, but I would imagine [I lost] probably around three kilos ... I'm looking forward to downing the rest of this drink."
Hamilton's Mercedes teammate George Russell completed the podium in third place and Hamilton was delighted with the car's performance all weekend.
"But what a day, what a weekend," he said. "Especially with missing FP1, [I'm] just so proud of the team -- this is an incredible result. Winning races and getting results like this is about the whole package.
"And of course, we know we don't have quite the pace of the two teams [Ferrari and Red Bull] ahead, but reliability is a huge fundamental part of the process so I'm so proud of my team for having the reliability that we do have.
"What a great result ... George did a great job as well, so to get a second and a third, it's really special for us."
After plenty of speculation around his future in Formula One, the 37-year-old Hamilton insisted he is eager to remain in the sport for a number of years.
At the French GP, Hamilton became just the sixth driver in F1 history to reach 300 career races and his current contract with Mercedes expires at the end of the 2023 season.
"I'm still fresh and still feel I've got plenty of fuel left in the tank," Hamilton said. "Of course I want to get back to winning ways and that's going to take time. I'm sure we'll sit down at some stage and talk about the future.
"This is my 300th GP and I woke up incredibly grateful for all the people who have been with me," he added. "Ron Dennis, Mercedes, Martin Whitmarsh, Toto, Niki Lauda ... I have been on an incredible journey with them.
"I'm enjoying it more than ever."