The oldest woman alive celebrated her 117th birthday in November 2016.

Emma Murano, who lives in Verbania, Italy, gave an unusual reason for her long life, stating that "being single" was the reason she has stayed alive for so long.

The Gerontology Research Group in Los Angeles — which records the ages of the world's oldest people — claims that there are currently just 46 supercentenarians – people who have lived past 110 – in the world.

While many of the world's oldest people live in Japan, supercentenarians live all over the world, from Italy to Jamaica.

Whether it's a healthy diet or a relaxed view of the world they have to thank, the oldest people on earth all have their secrets to longevity.

We've listed the secrets to long life according to five of the oldest people in the world. From eating raw eggs to following the Ten Commandments, this is how five supercentenarians stay young, ranked by their age:

5. Adele Dunlap (113 years old)

Adele is the oldest person living in the U.S.A, and the ninth oldest in the world. She was born on December 12 1902, and currently lives in New Jersey.

Both she and her son Earl are baffled by her age. He told NorthJersey.com that Adele never led an overly healthy lifestyle.

"She never went out jogging or anything like that," he said. "She smoked, and when my father had his first heart attack, they both stopped. I think she ate anything she wanted."

On the other hand, there is one food she swears by: oatmeal.

4. Ana Maria Vela Rubio (115 years old)

(Youtube (Youtube)

Ana Vela Rubio was born on October 30 1901, making her Spain's oldest living person. She was born in Andalusia, but moved to Barcelona more than 50 years ago. The supercentenarian has two children, four grandchildren and seventeen great-grandchildren.

According to her daughter, Rubio's compassion for others and positive attitude are what have kept her alive.

She told La Vanguardia in Spain that her mother "always sought the best for us, gave us the best education, has made us happy."

3. Nabi Tajima (116 years old)

(Youtube (Youtube)

Born on August 4 1900, Nabi Tajima is the oldest verified person living in Japan, and lives in the city of Kagoshima. She had nine children (seven sons and two daughters), but by September 2015 she had more than 140 descendants including 28 grandchildren, 56 great-grandchildren and 35 great-great-grandchildren.

She was crowned Japan's oldest citizen after the death of Misao Okawa, who held the title of the world's oldest person until she died on April 1 2015, aged 117 years and 27 days.

Tajima has never spoken in public about her lifestyle, but in 2014, Okawa told The Japan Times the key to longevity is "eating delicious things." These included ramen noodles and beef stew, as well as hashed beef and rice mackerel sushi.

"Eat and sleep and you will live a long time," she said. "You have to learn to relax.”

2. Violet Brown (116 years old)

(Youtube ) (Youtube)

Just five months ahead of Tajima, Violet Brown is Jamaica's oldest living person and, at the age of 116 years and 273 days, is the second-oldest verified living person in the world behind Emma Morano. The supercentenarian, who is affectionately known as "Aunt V" to her family, was born on March 10 1900 in the same part of the Island as Olympic champion Usain Bolt.

According to her son, Harold Brown, Violet eats smaller meals, and never eats pork or chicken. He told the Jamaica Observer that she "likes fish and mutton and sometimes she will have cow foot." Her diet contains plenty of locally-grown produce like sweet potatoes, breadfruit, oranges and mangoes.

Violet, a member of the Baptist church and a keen organist, also attributes her age to her faith. In 2011, she told the Jamaica Gleaner that following the Ten Commandments was her secret to a long life – "Honour your mother and father so your days may be long."

Her family has set up a charity, the Violet Mosse Foundation, which helps to care for the elderly.

1. Emma Morano (117 years old)

(OLIVIER MORIN/AFP/Getty) (AFP)

Emma Morano, thought to be the world's oldest person and the last to be born in the 1800s, celebrated her 117th birthday in Verbania, Italy on 29 November, 2016.

The supercentenarian, who was born in 1899, said that "being single" is the reason that she's still alive.

She also credits her long life to her simple, and slightly unusual, diet.

“I eat two eggs a day, and that’s it," she said. "And cookies. But I do not eat much because I have no teeth."

Morano says at age 20 – almost a century ago, when she was diagnosed with anaemia – she started eating two raw eggs and one cooked egg every day.

Ms Morano, who does not eat meat either, has lived alone since she left her husband in 1938.

“I didn’t want to be dominated by anyone,” she said.

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