Types of Good & Bad Bacteria

When we hear the word "bacteria," what usually comes to mind is something dirty--like germs that are bad for our health. Little did we know that there are two sides to the story of these tiny creatures. Bacteria are not only involved in processes that are bad for our health, but they are also central components of our immune system.

Lactobacillus and Bifidobacterium

• Some bacteria are actually good for human beings. Many types are often found inside the human digestive tract, particularly in the intestines. Two known groups of these good little guys are Lactobacillus and Bifidobacterium, which primarily aide digestion. They help break down difficult-to-digest foods--such as those that contain milk--that cannot be broken down by your body's enzymes alone, and in the process transform these food materials into short-chain fatty acids that are beneficial to the body. They also help regulate the bad bacteria by breaking them down in the gastrointestinal tract so that these harmful bacteria will not cause sickness.

Probiotics

• Probiotics refer to the good bacteria that are eaten to maintain a healthy digestive tract and replenish the good bacteria in our body. They are available in yogurt and yogurt drinks, and now also come in pills and capsules. Other kinds of good bacteria are those used in the production of foods such as cheese and milk.

Staphylococcus

• Bad bacteria are those that cause harm to humans, plants and animals. Collectively, they are called "pathogens." Staphylococcus is one of the most prevalent groups of pathogens because it causes many infections in people and animals. Staphylococcus (commonly known as "staph") is always present on our skin; however, when it is able to access a pore or burrow through the skin, it can cause various skin diseases like boils and pimples. When it is able to access our bloodstream via wounds or when it is ingested and grows to a large number in the body, it can cause pneumonia, food poisoning and toxic shock syndrome.

Streptococcus

• Streptococcus (or "strep") is again another of the prevalent pathogenic bacteria. Symptoms of a streptococcus infection range from a minor sore throat to very serious conditions like scarlet fever and bacterial endocarditis (a condition affecting the heart muscle).

Salmonella

• Salmonella usually infects the gastrointestinal tract but sometimes can also reach the bloodstream and cause more serious infections. Among these infections are food poisoning and gastroenteritis, and one species, S. typhi, is the causative agent of typhoid fever.