From my personal experience I can confirm that breathing right makes a big difference but the article fails to mention one very effective approach in many cases to improve breathing, septoplasty.
Issues you can have due to breathing defficiently (in my case, using the nose):
- Dehydration
- Headaches
- Extra energy spent / having to put effort in the task
- Need to empty / clear your mouth of food, etc so you can breath with your mouth