Centenarian Lilian Grundy doesn’t think she’s particularly old – she has an older sister-in-law in Australia who’s 104 and a younger sister who’s also still going strong.

Her life has taken in running a fish and chip shop, being a Citizen Advice Bureau adviser and – during the war – seeing a doodlebug hit her home town, Oldham. Her husband, Harry, died in 1970 and Lilian has no children.

The key to her longevity, she thinks, is being able to follow good medical advice: “I must have a good doctor. I think my secret really must be that I do what I’m told. If the doctor tells me to do something, I do it.”

So, is she right about her doctor being the key to her long life?

Plausibility rating: 7 out of 10. At first it seems obvious that medical care has played the most significant role in increasing life expectancy but in fact it’s a surprisingly contentious claim. Some historians argue that it is public health issues – clean water, better housing, the decline of smoking, safer food, workplaces and homes – that have played the larger role. Certainly life expectancy grew rapidly in the 19th century, ahead of the great medical advances of the 20th century such as antibiotics. And there were marked falls in life expectancy, particularly for men, from 1914-1919 and 1939-1945 so clearly non-medical factors have played a role too (think of that doodlebug from Lilian’s life history). In fact, one thorough study of the subject credited medical care with just 50% of the increase in life expectancy since 1950.

But what we’re interested in is the growth in the number of the oldest old and especially those who reach 100. Surely the main reason for the increase in centenarians is our ability to keep alive for longer people with multiple long-term conditions? Well, yes and no. A major study of Okinawans, who have more than twice the rate of centenarians of the US population, cites a range of factors that includes public health infrastructure, housing, income, and nutrition as well as access to better medical care.

So it looks as though Lilian’s longevity secret is part of the answer but not the whole answer.

photo credit: <a href=”http://www.flickr.com/photos/8404611@N06/3373106750″>Nurse</a&gt; via <a href=”http://photopin.com”>photopin</a&gt; <a href=”https://creativecommons.org/licenses/by/2.0/”>(license)</a&gt;