According to ehealthMD the medical term for hair loss is alopecia, there are different classification of alopecia, alopecia areata, is a disease in which well-defined bald patches occur. Alopecia total is, is an uncommon condition in which all hair on the scalp is lost. The cause is unknown. Alopecia universal is, is a total loss of hair on all parts of the body. Androgenetic alopecia is balding caused by heredity. Most people routinely lose between 70 and 150 hairs from their scalp each day, mainly through washing, brushing and combing, scalp hair starts to thin when more hair are lost through normal shedding that the scalp is able to renew. About 40% of the density of scalp hair has to be lost before thinning of the hair becomes noticeable. Research is looking into connections between hair loss and other health issues.
While there has been speculation about a connection between early-onset androgenetic alopecia and heart disease, a review of articles from 1954 to 1999 found no conclusive connection between baldness and coronary artery disease. The dermatologists who conducted the review suggested further study was needed. Environmental factors are under review. A 2007 study indicated that smoking may be a factor associated with age-related hair loss among Asian men. The study controlled for age and family history, and found statistically significant positive associations between moderate or severe androgenetic alopecia and smoking status. In May 2007, researchers at the University of Pennsylvania unveiled a new scientific breakthrough that may cure baldness with stem cells. A product could be on the market within three years. The researchers discovered that the growth of new hair producing follicles could be stimulated in mice by damaging their skin.
In February 2008 researchers at the University of Bonn announced they have found the genetic basis of two distinct forms of inherited hair loss, opening a broad path to treatments for baldness. The fact that any receptor plays a specific role in hair growth was previously unknown to scientists and with this new knowledge a focus on finding more of these genes may be able to lead to therapies for very different types of hair loss. An eight month study performed at the School of Pharmaceutical Sciences at the University of Science Malaysia showed daily supplements of a patented tocotrienol (vitamin E) complex may increase hair growth in people with male pattern baldness by 42 %. In May 2009, researchers in Japan identified a gene, SOX21, that appears to be responsible for hair loss in people.
In December 2010, scientists at the Berlin Technical University in Germany revealed they have grown the world’s first artificial hair follicles from stem cells. Research leader Roland Lauster said within five years millions of hair-loss sufferers could grow new hair from their own stem cells and have it implanted into their bald spots. He also announced that preparations for clinical trials were “already in motion”. In 2011, research showed that treatment with astressin-B caused the sudden growth of hair in mice bred for a propensity for stress. Astressin-B is a nonselective corticotropin-releasing hormone receptor antagonist. This may possibly be used in the future to aid in the regrowth of human hair. Later, Yale researchers found signals in fat cells that cause hair to grow. Researchers used genetic twins to determine environmental vs. genetic causes of baldness. Only 66 subjects were used but the use of twins allows control for age and genetics, two powerful confounders.
They found baldness associated with genetics, age, smoking, sun exposure, dandruff, a history of cancer, hypertension, sedentariness, and paradoxically, low testosterone. The latter was cited as supporting 5-alpha-reductase inhibitors which would increase the testosterone/DHT ratio. Hypertension (specifically high Diastolic blood pressure) was also found in the NHANES1 study and several others to be associated with baldness. The researchers also found marriage status in women to be associated with hair loss. In August 2012, scientists at the University of Pennsylvania announced that they had discovered an enzyme which caused baldness. They found that the enzyme Prostaglandin D2 (PGD2) was found to be present on the scalp of balding men at far higher levels than normal, preventing hair follicles from maturing and therefore stopping them from working and growing hair.
Dr. George Cotsarelis and his dermatological team at the University say that they are in talks with several pharmaceutical companies about developing treatments which could be available in two years. In April 2013, a meta-analysis of six observational studies with a total of 36 690 participants showed that vertex baldness is associated with an increased risk of CHD and that the relationship depends upon the severity of baldness, while frontal baldness is not. Thus, vertex baldness might be a marker of CHD and is more closely associated with systemic atherosclerosis than frontal baldness. In June 2013, scientists at the University of Pennsylvania discovered FGF9 as a possible treatment pathway for baldness, citing its critical role in hair follicle neogenesis in wound healing.