Smokeless tobacco is a tobacco product that is used by means other than smoking. Their use involves chewing, sniffing, or placing the product between gum and the cheek or lip. Smokeless tobacco products are produced in various forms, such as chewing tobacco, snuff, snus, and dissolvable tobacco products. Smokeless tobacco products typically contain over 3000 constituents. All smokeless tobacco products contain nicotine and are therefore highly addictive. Quitting smokeless tobacco use is as challenging as smoking cessation. Smokeless tobacco is much lower on the risk continuum than combusted products but varies in risk within that class of products (e.g., low nitrosamine Swedish-type snus versus other smokeless tobacco with high nitrosamine levels). It is estimated the safety risk of smokeless tobacco is similar to that of electronic cigarettes. There is no safe level of smokeless tobacco use. It is correlated with a number of adverse effects such as dental disease, oral cancer, oesophagus cancer, and pancreas cancer, as well as adverse reproductive effects including stillbirth, premature birth and low birth weight. Smokeless tobacco products contain cancer-causing chemicals. Approximately 28 chemical constituents present in smokeless tobacco are carcinogenic in nature, among which nitrosamine is the most prominent. Smokeless tobacco accounts for an abundance of deaths globally with a significant proportion of them attributed to Southeast Asia. Smokeless tobacco consumption is widespread throughout the world. Once addicted to nicotine from smokeless tobacco use, many people, particularly young people, expand their tobacco use by smoking cigarettes. Males were more likely than females to have used smokeless tobacco in the past month. Types Most smokeless tobacco use involves placing the product between the gum and the cheek or lip. Smokeless tobacco is a noncombustible tobacco product. Types of smokeless tobacco include: Dipping tobacco, a type of tobacco that is placed between the lower or upper lip and gums Chewing tobacco, a type of tobacco that is chewed Iqmik, an Alaskan tobacco product which also contains punk ash Snuff, a type of tobacco that is inhaled or "snuffed" into the nasal cavity Snus, similar to dipping tobacco although the tobacco is placed under the upper lip and there is no need for spitting Creamy snuff, a fluid tobacco mixture marketed as a dental hygiene aid, albeit used for recreation Naswar, an Afghan tobacco product similar to dipping tobacco Tobacco gum, a kind of chewing gum containing tobacco Gutka, a mixture of tobacco, areca nut, and various