Just a friendly reminder, even if you are in your 30s or 40s, make sure you get regular health check-ups. A cousin in his early 40s never thought to get a colonoscopy, and was found to have colon cancer 2 years ago. Thankfully, he's recovered. My best friend (in his 50s) didn't got to the doctor for a long time, and when he did a year and a half ago, found out he had very advanced prostate cancer. It was so large and his PSA was so high the doctors were shocked to find out it didn't spread and thankfully, now he's also recovered.
My sister beat breast cancer in her 40s, but last night, she informed me that she has HER2 triple positive breast cancer in her other breast. She gets checked regularly and we hope she caught it early as it's only 0.5 cm in size, but they aren't sure yet if it has spread or not.
My father, who was a mailman that walked 8+ miles a day on the job had a heart attack at 55, but thankfully survived and with quadruple bypass surgery, lived into is 80s before succumbing to a stroke.
You likely can't stop many of the ailments that might affect you, but early detection is key. Get your check-ups and don't let them lapse.