What causes bad breath even after brushing

What causes Bad Breath even after Brushing?
Bad breath can have many causes. The most common causes may be due to poor oral hygiene, a sinus infection, vomiting, GERD, ketoacidosis, or liver failure.
Everyone experiences bad breath at some point. It can be concerning to have unpleasant breath that brushing, and mouthwash do not seem to help.
While there are some benign causes for bad breath, some issues that cause this phenomenon are more serious and require medical attention.
Possible Bad Breath Causes
There are a number of different causes of bad breath, here are a few:
* Poor hygiene- Poor oral hygiene can cause bad breath. Failing to brush and floss your teeth consistently can make your breath smell because of plaque and bacteria buildup. Food that is not removed by flossing stays between your teeth, causing bad breath. Gum disease can also cause foul-smelling breath. It is also caused by poor oral hygiene. Neglecting your oral health leads to an accumulation of bacteria in your mouth, which will cause an odor on your breath. Dentures that are not thoroughly cleaned daily can also cause severe halitosis.
* Sinus infections- Sinus and respiratory infections can cause your breath to smell. These can be the result of viral colds, bronchitis, strep throat, and more. When bacteria move from your nose into your throat, it can cause bad breath. Some other symptoms of sinus infections include nasal drainage that is thick, a cold that lasts longer than 10–14 days, a low-grade fever, irritability and fatigue, postnasal drip, cough, sore throat, swollen eyes, or headache.
* Bowel obstruction- Intestinal obstructions are medical emergencies that happen when a blockage forms in either your large or small intestine. A blockage in your intestines can cause bad breath due to the feces trapped inside your intestines, but also from food you have eaten that cannot move down your intestinal tract, causing bad breath. Besides unpleasant breath odor, an intestinal obstruction can cause decreased appetite, constipation, nausea, vomiting, abdominal pain, and severe abdominal cramps.
* Vomiting- Prolonged vomiting, and the resulting dehydration, will cause bad breath from dry mouth. Saliva cleans your mouth and reduces odor, but when dehydrated, you will not produce enough saliva.
* GERD- Gastroesophageal reflux disease, GERD, can cause bad breath. This is when your stomach acid flows backward into the esophagus. This acidic backwash will irritate your esophageal lining, causing extreme discomfort. If you have GERD, you might experience mild to severe reflux that occurs a few times per week, heartburn in your chest after eating, difficulty swallowing, the feeling of a lump in your throat, laryngitis, persistent cough, asthma that is worse than before, or the inability to stay asleep.
* Ketoacidosis- Ketoacidosis is a severe complication if you have diabetes. It occurs when the body produces an elevated level of acids in the blood called ketones. It is a medical emergency that requires immediate attention. Ketoacidosis can cause bad breath from the dry mouth or vomiting associated with the condition.
* Liver failure- Liver failure can be either chronic or acute. Acute liver failure can happen quickly and requires immediate medical attention. It can also cause bad breath from dehydration. A person with liver failure can experience weight loss, jaundice, fatigue, appetite loss, nausea, diarrhea, itching, or easy bruising or bleeding.