Why are people living longer?

Key questions

What changes have occurred which mean we are now living longer than previous generations?

Are we now more informed about how to prolong our lives?

What changes have occurred which mean we are now living longer than previous generations?

During the twentieth century, life expectancy rose dramatically amongst the world's wealthiest populations from around 50 to over 75 years. This increase can be attributed to a number of factors including improvements in public health, nutrition and medicine. Vaccinations and antibiotics greatly reduced deaths in childhood, health and safety in manual workplaces improved and fewer people smoked. As a result of this - coupled with a decline in the fertility rate (the average number of children that women have in their lifetime) - many major industrial countries are facing an ageing population.

It is likely that life expectancy of the most developed countries will continue to slowly advance and then reach a peak in the range of the mid-80s. According to UN statistics for the period 2005 - 2010, Japan (82.6 years) has the world's highest life expectancy followed by Hong Kong (82.2 years) and Iceland (81.8 years). The world average is 67.2 years and the UK average is 79.4 years.

In the U.K, Life expectancy at birth increased by almost a decade in the first 50 years of the NHS (established in 1948). In 1948, 40% of people died before reaching pensionable age, but by 1996 this was reduced to just 7%.

During the Roman Empire, Romans had a approximate life expectancy of 22 to 25 years. In 1900, the world life expectancy was approximately 30 years and in 1985 it was about 62 years, just five years short of today's life expectancy.

Life expectancy changes as you get older. By the time a child reaches their first year, their chances of living longer increase. By the time of late adulthood, your chances of survival to a very old age are quite good. For example, although the life expectancy from birth for all people in the United States is 77.7 years, those who live to age 65 will have an average of almost 18 additional years left to live, making their life expectancy almost 83 years.

Are we now more informed about how to prolong our lives?

The three big reasons that people in the UK are living increasingly longer lives are:

• Food supply and nutrition

• Health

• Hygiene

These three things have all seen marked improvements in standards since the nineteenth and early twentieth centuries. However, another important factor is our knowledge of their importance to our health and life expectancy, and of the steps we can take to ensure that we lead a healthy lifestyle. Our access to relevant information has also improved dramatically as a result of scientific research and methods of information dissemination, for example the Internet.

For example:

• The packaging of food products at increasing numbers of shops and supermarkets displays the nutritional content of food and uses colour coding so that we know whether it is good for us. The importance of eating a balanced diet is widely known

• Government and charity websites provide information about the lifestyle choices we can make in order to reduce our risk of developing diseases. The effect that smoking cigarettes can have on our health is widely advertised, and warnings included on packaging. In the UK, a smoking ban in public places has been introduced and the age at which young people can buy cigarettes has been raised to 18 years

• Adverts on buses and tubes inform us of the importance of washing our hands and covering our mouths when we cough or sneeze in order to reduce the spread of illnesses and diseases. Health and safety legislation provides strict regulations for hygiene in restaurants, hospitals and factories

But following a healthy lifestyle is still a choice that we make, and not everyone chooses or is able to do so.

Links

• UN demographic statistics by country

• List of countries by life expectancy

Starter

How much fat?

How much do you know about daily calorie and fat allowances? What about how many calories there are in your favourite meals?

Have a look at the 'You are what you eat' activity to see more information about the amount of fat and number of calories in your favourite foods.

Who tells us how much to eat? Why do they tell us this?

Where else in the world are people told these things, and where are they not?

Main Activity

Food, health and hygiene: The key to longer life

We are now going to focus on the ‘big three' reasons why people in the UK live longer lives that the used to before the industrial age.

Study the list of facts or view the interactive and categorise them as food, health or hygiene breakthroughs (some might overlap slightly, just put them in both categories).

Are there any other facts not mentioned here that you have (i) learned in other subjects (ii) acquired as general knowledge (iii) gained through personal experience (e.g. vaccination jabs or knowledge of local health/ hygiene facilities and infrastructure) (iv) gained from watching this National Geographic film about Sardinians, Adventists and Okinawans.

Staying Alive

You are now going to write a 'risk diary' using the risk diary template. For the next few weeks, keep notes detailing how protected your own life is. You may walk through a fire door or use a level crossing, spot a health warning on a product you use or look at the calorie and fat content on the printed label of the food you eat. Do you fasten your seat-belt or ‘stand behind the yellow line' as a train approaches?

Try to record as many possible instances when you become aware of being subject to rules or advice designed to help you stay healthy and alive.

Plenary

What did you have for lunch today?

Have a brief discussion about school dinners. Should you be allowed to eat whatever you want?