People in Spain will soon have the longest lifespans of anyone in the world - here are their secrets

The healthcare system in Spain ranks as one of the world's best.

All Spanish citizens have a constitutionally guaranteed access to the country's universal healthcare system, and less than 20% of residents choose to obtain private health insurance.

Antonio Abellán, who conducts research on aging at the National Research Council in Spain, told The Guardian that social relationships play a large role in Spaniards' longevity.

Spain is not the only Mediterranean country to value family so much, but Abellán said being close with one's relatives goes a long way for health.

"It's not the only thing — nor the most important thing — but I think it goes some way to explaining the differences between Spain and other countries," Abellán told The Guardian. "It's a bonus. If you live better, you end up living longer."

On average, a Spanish person consumes 2.96 gallons of alcohol per year, according to El Pais. That is twice the global average — about 1.64 gallons per year — and higher than Europe's 2.88-gallon average.

Despite these elevated averages, the same data shows that 31% of the population does not drink at all.

Read more: 6 dangerous things that can happen to your body when you drink too much

Some research suggests that people who drink in moderation may live longer than those who don't drink. Many studies, however, have linked alcohol consumption to brain damage, liver disease, and various cancers, and one study says having just one drink above the recommended weekly limit can shorten one's life by 30 minutes.

Smoking cigarettes remains popular in Spain, even after the country passed a law in 2011 that prohibits smoking in bars and restaurants.

According to El Pais, there have been fewer cases of asthma among children since 2011, and the legislation may also result in fewer heart and lung illnesses.

Still, each Spanish person smokes an average of 1,499 cigarettes per year, according to Tobacco Atlas. The number is much higher than that of some countries, such as Norway's annual average of 553 cigarettes per person, but Spain is still ahead of Japan, where each person smokes an average of 1,583 cigarettes per year.