<P> The legal drinking age is the age at which a person can legally consume alcoholic beverages . These laws cover a wide range of issues and behaviors, addressing when and where alcohol can be consumed . The minimum age alcohol can be legally consumed can be different from the age when it can be purchased in some countries . These laws vary among different countries and many laws have exemptions or special circumstances . Most laws apply only to drinking alcohol in public places, with alcohol consumption in the home being mostly unregulated (an exception being the UK, which has a minimum legal age of five for supervised consumption in private places). Some countries also have different age limits for different types of alcoholic drinks . </P> <P> Kazakhstan, Oman, Pakistan, Qatar, Sri Lanka, Tajikistan, Thailand, United Arab Emirates, Federated States of Micronesia, Palau, Paraguay, Solomon Islands, India (certain states), the United States (except U.S. Virgin Islands and Puerto Rico), Yemen (Aden and Sana'a), Japan, Iceland, Canada (certain Provinces and Territories), and South Korea have the highest set drinking ages; however, some of these countries do not have off - premises drinking limits . Austria, Antigua and Barbuda, Belgium, Bermuda, British Virgin Islands, Cuba, Ethiopia, Gibraltar, Luxembourg, Nicaragua, and Zimbabwe have the lowest set drinking ages . </P> <P> The most commonly known reason for the law behind the legal drinking age is the effect on the brain in adolescents . Due to the fact that the brain is still maturing, alcohol can have negative effect on the memory and long - term thinking . Alongside that, it can cause liver failure, and create a hormone imbalance in teens due to the constant changes and maturing of hormones during puberty . </P> <P> The most common minimum age to purchase alcohol in Africa is 18 . Although it varies from the lowest age limit in Ethiopia being only 15 years, Zimbabwe with a minimum purchase age of 16 years, Gambia with a age limit of 17 years and Uganda where the minimum legal purchase age is 18 but minors aged 16 or 17 may consume a glass of beer, wine or cider with a meal at a restaurant . Cameroon and Egypt are the only countries in Africa with a minimum purchase age of 21 years . However Algeria, Angola (except Luando Province), Central African Republic, Comoros, Equatorial Guinea, Gabon, Guinea - Bissau, Morocco, Togo, Tunisia and the Western Sahara have no laws on the book restricting the sale of alcohol to minors . In Libya, Somalia and Sudan the sale, production and consumption of alcohol is completely prohibited . </P>

Why do you have to be 21 to buy alcohol
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