Fans who haven't followed LIV Golf this season got a surprise Thursday while watching the PGA Championship. Bryson DeChambeau — who had built a reputation as a hulking power golfer — showed off a slimmed-down physique at Oak Hill Country Club.
His body transformation isn't a recent development: His weight loss has been taking place over several months, and he talked about his dietary changes in November 2022. He told the "Five Clubs" podcast he "started to feel weird" from his former diet that fueled his training regimen.
"I ate improperly for almost a year and a half and I was starting to feel weird,” DeChambeau said. "My gut was all messed up, and so I went completely healthy, went on a Whole30 diet, got a nutritionist, did blood work, measured stuff in my gut biome. I was super inflamed.
"And then just recently since I’ve been using this new chef, I lost 20 pounds in a month."
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Here's everything you need to know about DeChambeau's weight loss, starting with his decision to become the "Incredible Bulk," his decision to trim down and the Whole30 diet:
Bryson DeChambeau before and after photos
A side-by-side comparison of DeChambeau shows how drastically his body has changed in that time:
Bryson DeChambeau weight loss
DeChambeau said he decided to drop weight because he was feeling the effects of the diet he was following to fuel his workout regimen.
In June 2020, DeChambeau discussed with Men's Health how he began training with Greg Roskpof of Muscle Activation Techniques to gain weight "without losing mobility." The aim: to improve his driving distance. He began the regimen and accompanying diet in late 2019 and experienced terrific short-term results, winning both the Rocket Mortgage Classic and U.S. Open in 2020 and the Arnold Palmer Invitational in 2021.
He also led the PGA Tour in average driving distance in the 2019-20 (322.1 yards per drive) and 2020-21 (332.7) seasons. When he spoke to Men's Health, DeChambeau said he had gained 20 pounds. Multiple reports indicate his weight gain topped out at 50 pounds.
He told the "Five Clubs" podcast that most of that weight was fat.
"We trained really hard and I ate things that were not great for my system that I was very sensitive to," DeChambeau said. "And ultimately it got to the point where it was a little too much. And that’s when I started to back off of that."
The Daily Star reported that DeChambeau is down 44 pounds. His PGA Tour bio lists him at 6-1, 235.
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What is Bryson DeChambeau's health issue?
DeChambeau says his previous diet caused severe inflammation and general gastrointestinal distress. (He told Men's Health he had a 2:1 carb-to-protein ratio in his diet.) Golf Digest pointed out this week that DeChambeau also struggled with hip and wrist injuries in 2022.
He told The Telegraph (subscription required) recently that doctors delivered a sobering message at the start of his weight loss journey.
"They did blood work, measured stuff in my gut biome and I was super inflamed. So they said, if you want to live a longer life, you definitely have to change your diet, because your gut’s not liking what's going on. So I did," he said.
On the "Five Clubs" podcast, he advised golfers not to try bulking up, telling them to "get stronger but in a healthy way." He also suggested getting blood sensitivity tests to determine the best diet.
He reiterated those points last week, adding that his swing likely will change to accommodate the weight loss:
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Bryson DeChambeau diet and workout
DeChambeau added further context Thursday while speaking with reporters after his opening round at the PGA Championship. He was the clubhouse leader at 4 under par when play was suspended because of darkness.
He said the pounds he dropped with Whole30 were water weight. He said he achieved the drastic loss not only with reduced caloric intake but also with changing the types of food he was eating.
"A lot of diet changes … going down to 5,000 calories down to 2,900, whatever it is now," he said (via the Toronto Sun). "Carrie, my chef, she helps me out with that. But eating properly instead of eating stuff that inflames my body.
"I was allergic to corn, wheat, gluten, dairy. Pretty much everything I liked, I couldn’t eat. I took that out. Started taking it out in August (2022) and over the course of time I’ve lost all this inflammation, lost a lot of fat and slimmed down like crazy."
As he told the "Five Clubs" podcast, he feels "a lot more at ease" after slimming down.
"Finally, I look like I’m 20 again, not 35," he said.
According to Healthline, the Whole30 program is a 30-day "elimination diet" that removes certain foods from people's systems. It is designed not only for weight loss but also to identify foods that give them digestive issues.
The Whole30 diet allows for consumption of meat, vegetables, fruit, tree nuts and seeds and healthy fats. It restricts the consumption of sugar, grains, legumes, dairy, alcohol and processed food — most of which DeChambeau said he cut from his diet.
Per Healthline, Whole30 is designed to be maintained only over a 30-day period.
Bryson DeChambeau age
DeChambeau is 29. He was born Sept. 16, 1993.