Well, well, well, it looks like Nick Jonas has matured rather nicely, doesn't it?
We can confirm that the baby brother of the trio of US singing siblings is all grown (and buffed) up, after he shared a shirtless snap on Instagram during a gym workout.
Nick Jonas showed off his buff body
The star usually shies away from posting selfies but decided to flex his muscles and show off his rippling six pack on the photo site.
"I never do this but... Healthy living and fitness update. Post workout picture. #diabeticinshape #2.0," the 20-year-old wrote alongside the snap.
Nick back in 2006
Nick was diagnosed with Type 1 diabetes at the age of 13 and since then, he has cut back on his sugar intake, which has helped him achieve his body shape.
He told Good Housekeeping in 2011: "When I wake up, the first thing I do is check my blood sugar, see where I am. Then, I usually eat breakfast, typically an omelet because it has eggs, which are good, and other things that help me stay stable."
Check out more amazing celeb body transformations below...
From Wimp To Wow! 13 Stars Who have Buffed Up
From Wimp To Wow! Stars Who Have Buffed Up(01 of28)
Craig David (credit:Getty)
From Wimp To Wow! Stars Who Have Buffed Up(02 of28)
Craig David (credit:Craig David/Twitter)
From Wimp To Wow! Stars Who Have Buffed Up(03 of28)
Kenzie (Blazin' Squad) (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(04 of28)
Kenzie (Blazin' Squad) (credit:YouTube)
From Wimp To Wow! 13 Stars Who Have Buffed Up(05 of28)
Nick Jonas (credit:Getty)
From Wimp To Wow! 13 Stars Who Have Buffed Up(06 of28)
Nick Jonas (credit:Instagram)
From Wimp To Wow! Stars Who Have Buffed Up(07 of28)
Aaron Johnson (credit:Getty Images)
From Wimp To Wow! Stars Who Have Buffed Up(08 of28)
Aaron Johnson (credit:Kick Ass 2)
From Wimp To Wow! Stars Who Have Buffed Up(09 of28)
Daniel Craig (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(10 of28)
Daniel Craig (credit:Columbia)
From Wimp To Wow! Stars Who Have Buffed Up(11 of28)
Former Children's BBC presenter Andi Peters (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(12 of28)
Former Children's BBC presenter Andi Peters (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(13 of28)
Hugh Jackman (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(14 of28)
Hugh Jackman (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(15 of28)
Tom Hardy (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(16 of28)
Tom Hardy (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(17 of28)
Harry Judd (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(18 of28)
Harry Judd (credit:PA)
From Wimp To Wow! Stars Who Have Buffed Up(19 of28)
Jake Gyllenhaal (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(20 of28)
Jake Gyllenhaal (credit:Splash/Disney)
From Wimp To Wow! Stars Who Have Buffed Up(21 of28)
Chris Pratt (credit:Getty)
From Wimp To Wow! Stars Who Have Buffed Up(22 of28)
Chris Pratt (credit:Chris Pratt/Twitter)
From Wimp To Wow! Stars Who Have Buffed Up(23 of28)
Eoghan Quigg (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(24 of28)
Eoghan Quigg (credit:Now magazine)
From Wimp To Wow! Stars Who Have Buffed Up(25 of28)
Will Smith (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(26 of28)
Will Smith (credit:Ali)
From Wimp To Wow! Stars Who Have Buffed Up(27 of28)
Jodie Marsh (credit:WENN)
From Wimp To Wow! Stars Who Have Buffed Up(28 of28)
Jodie Marsh (credit:Jodie Marsh/Twitter)
Jonas Brothers Photos
FIJI Water At Lacoste L!VE Coachella Desert Pool Party - Day 1(01 of18)
PALM SPRINGS, CA - APRIL 13: Musicians Nick Jonas (L) and Joe Jonas of the Jonas Brothers attend the FIJI Water At Lacoste L!VE Coachella Desert Pool Party on April 13, 2013 in Palm Springs, California. (Photo by Imeh Akpanudosen/Getty Images for FIJI) (credit:Getty Images)
Jonas Brothers(02 of18)
The Jonas Brothers, perform at the Vina del Mar International Song Festival in Vina del Mar, Chile, Tuesday, Feb. 26, 2013. Believed to be one of the largest musical events in Latin America, the annual 5-day festival was inaugurated in 1960. (AP Photo/Luis Hidalgo) (credit:AP)
Jonas Brothers(03 of18)
The Jonas Brothers, from left to right Nick, Joe and Kevin, perform at the Vina del Mar International Song Festival in Vina del Mar, Chile, Tuesday, Feb. 26, 2013. Believed to be one of the largest musical events in Latin America, the annual 5-day festival was inaugurated in 1960. (AP Photo/Luis Hidalgo) (credit:AP)
Jonas Brothers(04 of18)
Joe Jonas, member of the band Jonas Brothers, performs at the Vina del Mar International Song Festival in Vina del Mar, Chile, Tuesday, Feb. 26, 2013. Believed to be one of the largest musical events in Latin America, the annual 5-day festival was inaugurated in 1960. (AP Photo/Luis Hidalgo) (credit:AP)
Kevin Jonas(05 of18)
Kevin Jonas, member of the band Jonas Brothers, performs at the Vina del Mar International Song Festival in Vina del Mar, Chile, Tuesday, Feb. 26, 2013. Believed to be one of the largest musical events in Latin America, the annual 5-day festival was inaugurated in 1960. (AP Photo/Luis Hidalgo) (credit:AP)
Nick Jonas(06 of18)
Nick Jonas, member of the band Jonas Brothers, performs at the Vina del Mar International Song Festival in Vina del Mar, Chile, Tuesday, Feb. 26, 2013. Believed to be one of the largest musical events in Latin America, the annual 5-day festival was inaugurated in 1960. (AP Photo/Luis Hidalgo) (credit:AP)
CHILE-VINA SONG FESTIVAL-JONAS(07 of18)
Joe, and Kevin Jonas (R) of the American pop rock band Jonas Brothers perform during the 54th Vina del Mar International Song Festival on February 26, 2013 in Vina del Mar, Chile. AFP PHOTO/MARTIN BERNETTI (Photo credit should read MARTIN BERNETTI/AFP/Getty Images) (credit:Getty Images)
Jonas Brothers Surprise Inner City School - Launch We Day Minnesota(08 of18)
MINNEAPOLIS, MN - FEBRUARY 06: Nick Jonas of the musical trio the Jonas Brothers shakes hands with Siddartha Paari after surprising 600 students at Minneapolis Patrick Henry High School to launch 'We Day' on February 6, 2013 in Minneapolis, Minnesota. (Photo by Adam Bettcher/Getty Images for Free The Children) (credit:Getty Images)
Jonas Brothers Surprise Inner City School - Launch We Day Minnesota(09 of18)
MINNEAPOLIS, MN - FEBRUARY 06: (L-R) Joe Jonas, Kevin Jonas and Nick Jonas of the musical trio the Jonas Brothers surprise 600 students at Minneapolis Patrick Henry High School to launch 'We Day' on February 6, 2013 in Minneapolis, Minnesota. (Photo by Adam Bettcher/Getty Images for Free The Children) (credit:Getty Images)
KIIS FM's 2012 Jingle Ball - Night 1 - Show(10 of18)
LOS ANGELES, CA - DECEMBER 01: Musician Kevin Jonas of the Jonas Brothers performs onstage during KIIS FM's 2012 Jingle Ball at Nokia Theatre L.A. Live on December 1, 2012 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for Clear Channel) (credit:Getty Images)
Jonas Brothers Surprise Inner City School - Launch We Day Minnesota(11 of18)
MINNEAPOLIS, MN - FEBRUARY 06: (L-R) Joe Jonas, Kevin Jonas and Nick Jonas of the musical trio the Jonas Brothers surprise 600 students at Minneapolis Patrick Henry High School to launch 'We Day' on February 6, 2013 in Minneapolis, Minnesota. (Photo by Adam Bettcher/Getty Images for Free The Children) (credit:Getty Images)
KIIS FM's 2012 Jingle Ball - Night 1 - Show(12 of18)
LOS ANGELES, CA - DECEMBER 01: (L-R) Musicians Nick Jonas, Joe Jonas, and Kevin Jonas of The Jonas Brothers perform onstage during KIIS FM's 2012 Jingle Ball at Nokia Theatre L.A. Live on December 1, 2012 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for Clear Channel) (credit:Getty Images)
KIIS FM's 2012 Jingle Ball - Night 1 - Show(13 of18)
LOS ANGELES, CA - DECEMBER 01: Singer Joe Jonas of the Jonas Brothers performs onstage during KIIS FM's 2012 Jingle Ball at Nokia Theatre L.A. Live on December 1, 2012 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for Clear Channel) (credit:Getty Images)
KIIS FM's 2012 Jingle Ball - Night 1 - Show(14 of18)
LOS ANGELES, CA - DECEMBER 01: Musicians Nick Jonas (L) and Joe Jonas of the Jonas Brothers perform onstage during KIIS FM's 2012 Jingle Ball at Nokia Theatre L.A. Live on December 1, 2012 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for Clear Channel) (credit:Getty Images)
KIIS FM's 2012 Jingle Ball - Night 1 - Arrivals(15 of18)
LOS ANGELES, CA - DECEMBER 01: (L-R) Musicians Kevin Jonas, Joe Jonas and Nick Jonas of the Jonas Brothers attend KIIS FM's 2012 Jingle Ball at Nokia Theatre L.A. Live on December 1, 2012 in Los Angeles, California. (Photo by Imeh Akpanudosen/Getty Images) (credit:Getty Images)
KIIS FM's 2012 Jingle Ball - Night 1 - Show(16 of18)
LOS ANGELES, CA - DECEMBER 01: Musicians Nick Jonas (L) and Joe Jonas of the Jonas Brothers perform onstage during KIIS FM's 2012 Jingle Ball at Nokia Theatre L.A. Live on December 1, 2012 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for Clear Channel) (credit:Getty Images)
KIIS FM's 2012 Jingle Ball - Night 1 - Show(17 of18)
LOS ANGELES, CA - DECEMBER 01: Musician Nick Jonas of the Jonas Brothers performs onstage during KIIS FM's 2012 Jingle Ball at Nokia Theatre L.A. Live on December 1, 2012 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for Clear Channel) (credit:Getty Images)
KIIS FM's 2012 Jingle Ball - Night 1 - Show(18 of18)
LOS ANGELES, CA - DECEMBER 01: Musicians Joe Jonas (L) and Kevin Jonas of the Jonas Brothers performs onstage during KIIS FM's 2012 Jingle Ball at Nokia Theatre L.A. Live on December 1, 2012 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for Clear Channel) (credit:Getty Images)