Allium containing foods like onions, leeks, shallots, scallions, chives and garlic will create bad breath instantly. This is because, they already contain the sulphur compounds, Mercaptans, produced by these bacteria. Once they are digested they release a strong smell from the skin, urine and lungs
Sugar is an excellent food for anaerobic bacteria in the mouth, all bacteria thrive in a sugar environment.
Dairies contain high proteins that bacteria use as a food source to create odors. The end result is a buildup of amino acids, which are easily transformed into volatile sulfur compounds by the anaerobic bacteria located within the surface of your tongue and throat.
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Sulfur containing foods like broccoli, cauliflower, cabbage, asparagus, and brussels sprouts are probably the worst for your breath. Gas inducing food. Oral malodour can be produced by anaerobic bacteria that breed below the surface of the tongue, in the back of the throat and on the tonsils. As mentioned before, these particular bacteria digest proteins and make amino acids and a waste product called Volatile Sulphur Compounds. There are three main Volatile Sulphur compounds; Hydrogen Sulphide, Methyl Mercaptan, and Hydrogen Disulphide. These three compounds will make up 90% of all bad breath smells.
e. High Protein
High protein foods like beef, chicken, fish. If a person does not have enough enzymes, the food cannot be digested fast, consequently it sits out too long, so it spoils and ferments in the gut. Undigested protein reaching the colon is perfect food for the bacteria bacillus colli, they thrive on it. Dr Kellog said: “A healthy bowel is about 85% friendly lactobacillus bacteria and 15% unfriendly, gas producing bacillus coli.” So food high in protein can cause bad breath, first because proteins are the excellent meal for bad microorganisms and second because undigested food in the gut decays, producing foul gas and toxemia.
f. Fruit Juices
Fruit juices from tomato, pineapple, cranberries, grapefruit, blueberries, sweetened fruit juice, etc are acidic. Acids make the bacteria multiply faster and can leave a bitter taste in the mouth.
Coffee is very acidic and dries the mouth. It happens when acids accumulate in the mouth and block oxygen molecules. The production of saliva diminishes as the acid and bacteria increase. Saliva contains oxygen, thus helping the mouth to stay fresh. The bacteria that create bad bread are anaerobic, which means that they thrive and produce more sulphur in the absence of oxygen. Consequently bacteria grow and cause bad breath. Coffee also affects the intestines, 8 ounces of this drink can destroy 20% of the friendly bacteria in the gut.