Morning bad breath or a metallic taste in spite of good oral hygiene could indicate impaired kidney function. As the kidneys are weak, their ability to remove urea from the blood decreases. Urea accumulates and breaks down into ammonia in saliva, leading to bad breath and a metallic taste. Per Nephrology Dialysis Transplantation, uremic fetor (breath odor caused by urea) is a typical sign of chronic kidney disease.

Final Note

Kidney disease is often called a “silent illness,” but noticing nighttime symptoms such as swelling, frequent urination, , insomnia, cramps, or bad breath can help detect the problem early and allow timely treatment.

Regular kidney function check-ups, maintaining a balanced diet, and keeping blood pressure under control are good ways to protect kidney health.