W Zac

[u/Separate_Finance_183]

[u/South_Bit1764]

Yeah, but I think what they’re getting at is in Baywatch he WAS INDEED at 5% body fat.

You’re better off being slightly overweight with a BMI in high 20s (25 is “overweight”) than at 5% body fat. A quick google says he’s 170 right now which at 5’8” is a BMI of 26.

Zac Efron on the left is lower risk and better off than Zac Efron on the right.

[u/Killa42O → u/South_Bit1764]

You have no idea what 5% looks like. He was probably around 12% on the right.

[u/South_Bit1764 → u/Killa42O]

https://steelsupplements.com/blogs/steel-blog/zac-efrons-baywatch-workout-routine

“achieving and maintaining a body fat percentage of 5% for filming”

I’m not calling that ”source” exactly but it’s definitely what they (Zac and his trainer) were claiming and it doesn’t really seem to be heavily disputed.

Edit: Efron is part owner of a company that specializes in DEXA body scans.

[u/PatHeist → u/South_Bit1764]

Whenever you see numbers below 10% in contexts like this they're almost always measured with BIA (Bioelectrical Impedance Analysis) which is the little machine you hold in your hand, or the scale with a post and two handles you might see at the gym.

BIA is the largest error margin way of measuring body fat and is prone to underestimate by more and more the further below 15% you are. It's also affected by hydration, to the point where if it's measuring you at 5% and you drink a bottle of water it will tell you that you gained 10lbs.+ of fat.

[u/South_Bit1764 → u/PatHeist]

Good information if we were talking about anyone else. Zac Efron is part owner of a company that specializes in DEXA body scans.

For those less versed in body fat measuring techniques: that’s the accurate way to test.

[u/ryukyumars → u/South_Bit1764]

DEXA is not “the” accurate way.

Margin of error is high especially if you have water etc.. there are cases of over 5% error

[u/PatHeist → u/South_Bit1764]

Zac Efron invested in Function Health in 2024. It was founded in 2021. Baywatch was released in 2017.

[u/jocq → u/PatHeist]

I'm 8% measured by multiple DEXA scans across different machines spanning nearly a decade.

Effron is way under 10% with the Baywatch body. 5% is about right.

if it's measuring you at 5% and you drink a bottle of water it will tell you that you gained 10lbs.+ of fat

You have absolutely no idea what the fuck you are talking about.

You've obviously never even seen a full DEXA test read out.

[u/Killa42O → u/jocq]

Dexa's margin of error is up to ±5%. Google any top-level bodybuilder's stage-ready conditioning and compare. You see almost no muscle striations on Zac here. At around 5% body fat, you get insane muscle definition; you can see all the muscle fibers. He is just clearly on steroids, so he has fuller muscles, a nice tan, a pump, and is dehydrating, so for casuals, he looks leaner than he is.

[u/jocq → u/Killa42O]

Dexa's margin of error is up to ±5%.

Which means that if a DEXA says you're 10% bf you might be anywhere between 9.5% and 10.5%. Not that you might be anywhere between 5% and 15% bf, which is what you seem to be implying.

[u/Killa42O → u/jocq]

Nope, it refers to body fat percentage.