(AGA) Also known as Male or Female Pattern Hair Loss or Pattern Baldness. This is the most common type of hair loss. Affects approximately 60 million people in America: 40 million males and 20 million females suffer from hairloss. About 95% of the men and women who have thinning hair or hairloss problems can attribute their hair thinning and hairloss  to pattern hairloss.

(AA) A sudden loss of hair in round irregular patches, where the scalp is not visibly inflamed. This type of hair loss occurs in individuals who have no obvious skin disorders or serious disease. The cause is unknown, but may be related to stress or auto-immune disease. Alopecia Areata may be confined to a few areas of the scalp and is often reversed in a few months. According to the National Alopecia Areata Foundation, an estimated four million men, women and children suffer from this type of hair loss.

A temporary scattered hair loss at the end of pregnancy.

A premature shedding of hair in the resting or telogen phase, which can result from various causes such as childbirth, shock, side effects of various medications, fever, etc. Some women also experience sudden hair loss when they discontinue use of birth control pills or follow extreme diets too low in protein. The hair loss is usually reversed once the condition is resolved.

Patchy or scattered hair loss due to the use of hot combs or repetitive traction of the hair by pulling or twisting. This type of hair loss could also occur after excessive applications of chemical softening agents such as relaxers and permanent waves, especially those that use lye-based perms and colorings. This condition is usually reversed once the trauma is stopped.

Heredity can cause pattern hairloss when there is a family history having a genetic predisposition to thinning hair and hair loss. It is commonly known as male or female pattern hair loss. In pattern hair loss, the enzyme 5-Alpha-Reductase is primarily responsible for the conversion of the hormone Testosterone into the harmful hormone Di - Hydro - Testosterone (DHT), which starts the process of your losing your hair.

If you are a male and any of the following family members have or had thinning hair or hair loss, you also may experience male pattern hair loss: your father, grandfather, uncle or brother. If you are a female, and any of the following family members have or had thinning hair or hair loss, you also may experience female pattern hair loss: your father, grandfather, uncle or brother or your mother, grandmother, aunt or sister.

Many people are not aware that various kinds of prescription medications may either cause or contribute to thinning hair and hairloss. This includes various acne treatments, anti-depressants drugs, birth control pills, chemotherapy and other drugs, such as those for lowering cholesterol, high blood pressure, treating ulcers, arthritis and blood thinners. You may review this separate extended list of prescription drugs which can cause hairloss

Various kinds of health and medical conditions such as hyperthyroidism and lupus can cause thinning hair. Some women experience sudden hair loss at the conclusion of pregnancy or two to three months after discontinuing the use of birth control pills.

It is commonly thought that extended periods of high stress can cause or contribute to hair loss as stress may increase a constriction of the blood supply to the scalp. Sometimes after surgery, some individuals may experience either temporary or long term hair loss.

Poor diet and nutrition may also contribute to losing one's hair. This may include diets high in animal fat (too much red meat), too much protein, too much fast food or quick weight loss diets.