Nick Jonas got a big push to start taking care of his health from someone very close to him: his brother Joe Jonas.

The Jonas Brothers appeared on the July 24 episode of Penn Badgley's Podcrushed podcast where Nick explained that his health started declining when the trio were doing a school tour in 2006 when he was around 13 years old, per People.

"I started losing a ton of weight and you know, drinking a ton of water, use the bathroom al the time, all the signs now that I know are symptoms of type 1 diabetes," he said, adding, "I had no idea. I just knew that I wasn't feeling well and was losing all this weight... it's actually a testament to the lack of information and awareness there was around type 1 at this time."

According to the American Diabetes Association, Type 1 diabetes is an autoimmune disease most often diagnosed in young people, though it can develop at any age. The condition causes the pancreas to make little or no insulin, a hormone that helps blood glucose, or blood sugar, to enter the body's cells to be used as energy.

The troubling signs caught the attention of Joe, then 16, when he was "sort of like chaperoning me" during a trip. Joe recalled thinking how his younger brother was "so skinny," with their older brother Kevin Jonas adding that he could "see every bone."

"We went to the pool one day and he saw my back and called my parents and said, 'You know, something's really wrong. You have to get down here,'" Nick said.

He recalled seeing "great doctors" to address how "awful" he had been feeling and learning that his glucose level was extremely high compared to the normal maximum for someone of his age, ultimately leading to his diagnosis. However, after a few days in the hospital, he was back to performing on stage "within a week's time of being diagnosed."

The "Jealous" singer has been an outspoken advocate for the condition ever since, even praising the advancements made managing the disease, such as the Dexcom G7 glucose monitor, since his was diagnosed.

"I'm coming up on my twentieth year living with the disease, which coincides with the twentieth year of the band, coincidentally," he said. "The leaps we've made though, it's pretty astounding, tech-wise, and even just information that we have now as opposed to what we had then is really wild."

Aside from managing his health, Nick is also busy with his music career — even recently making his return to Broadway in The Last Five Years — and being a dad to his and wife Priyanka Chopra Jonas' 3-year-old daughter Malti Marie. The little one even has her own special name for her dad's group.

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