Should someone in their 30s bother about popping and cracking joints?
Well, the simplest answer will be.
As long as the sound does not come with any pain or swelling, you do not need to worry. Popping or cracking sound may be just gas bubbles bursting into the fluid around the joint, or the sound of ligaments and tendons being drawn and released.
Do you notice this more when you repeatedly move the joint (when you press the shoulder in the gym, for example)? A soft snapping or clicking sound is also sometimes caused by a tight muscle or tendon caused by a tight structure.
To help calm the snapping, try some gentle stretching that involves the muscles around the joint.
Do you have any joint injuries? during that time if your ligament is unable to heal correctly, then your joint may pop when you move it.
If you are still young, but keep in mind that joints may start to get noisy as you age, as some cartilages degenerate over time. But if you feel any discomfort in the joint, see your doctor. It is possible that you have a ligament injury or arthritis damage that needs to be investigated.