Life expectancy has been increasing steadily throughout the last century, as of 2016 babies born in the UK have a 1 in 3 chance of living to 100, according to the Office for National Statistics. This is thanks in part to the wonders of modern medicine, better access to quality food and the sharp increase in quality of life, but despite this longevity is not equal, some people seem to live far longer than even today’s average.
If I asked what you think makes us live longer you might say a healthy lifestyle, eating right and moderate exercise. I would agree, and supplement your response with references to the average weight of a Brit or American versus the average weight of a Japanese or Indian person and maybe their dietary habits — but you would shut me down with an anecdote about your friend’s grandmother, who drank and smoked every day and lived to 92.
Outliers like these are the first problem when discussing longevity, we all know that person, maybe a relative or friend who lived far beyond the norm and didn’t seem to do anything different than anyone else. Sometimes this can be down to genetic factors but genetics isn’t a guarantee of a long life either.
The first thing to keep in mind is that there are are so many contributing factors to longevity that it is hard to get a clear picture. One of the last things we might think about is deceit, but it is actually quite common for people to lie about their age in order to qualify for an earlier pension or avoid military service for example, and if you are old enough or claim to be, you can have plausibly unofficial documents supporting that claim.
A study conducted by Saul Justin Newman into areas with a high density of so called ‘supercentenarians’ (those who live over a 110) found that since the US state-specific introduction of birth certificates there was a 69–82% fall in the number of supercentenarian records. The title of the study aptly sums up the issue: Supercentenarians and the oldest-old are concentrated into regions with no birth certificates and short lifespans.
An example of this is a Tunisian man named Amri Ali, who claimed to have been born in 1880. He wanted his feat of longevity recognized by Guinness, but passed away in 2010, just shy of his 130th birthday. Because of the lack of evidence however this never happened.
Similarly an Indonesian man named Sodimedjo claimed to be 146 and even had a residency card with his birthdate on it, 1870. However, he did not have a valid birth certificate, as Indonesia didn’t start recording births until 1900 and thus his claim could not be substantiated.
So who is the oldest person ever?
Topping the list of verified oldest people is French woman Jeanne Calment, who died at the age of 122. But even this officially recognized achievement has come under scrutiny in recent years, with Russian mathematician Nikolay Zak casting doubt on Calment’s age. He argues there is evidence to suggest that Jeanne’s daughter impersonated her.
According to record Yvonne Calment died of pleurisy in 1934, but Zak is suggesting that it was actually Jeanne who died and her daughter assumed her identity to avoid paying inheritance tax. Zak’s paper created enough controversy that some experts are calling for exhuming the bodies of Jeanne and Yvonne for DNA analysis.
So assuming they aren’t lying, what is it about people like Jeanne that enables them to live to over 100? One clue comes from a television interview in which Jeanne stated,“J’ai jamais été malade, jamais, jamais” (I have never been ill, never ever).
Not getting sick
A strong immune system means you get less sick less often, which I’m sure we can all accept at a common sense level increases your chance of living a longer life. Immune system function declines with age, leading to chronic inflammation, known as inflammaging. So the stronger the immune system you have to begin with, the stronger it will be at a later age and therefore the less chance you have of being wiped out by illness. For example, you might survive a virus in your 90’s that ends the life of someone in their 70’s.
But what if you aren’t blessed with a powerful immune system? This is the deficit we try to make up for with modern science, maybe we can’t give you a stronger immune system yet but we can take steps to eradicate the illnesses that affect us in the first place.
But what if you could simply avoid them? This is is where climate becomes important, harsh winters increase the chance of illness as viruses tend to live longer in colder temperatures and lower humidity. People are also likely to spend more time inside which brings them in contact with more surfaces and in closer proximity to other people, further increasing chances for viruses to spread. Mortality rates are generally higher in winter with around 21,900 excess winter deaths in 2018 to 2019 in the UK. It’s no surprise that so many of us dream of retiring to warmer climates, but its not just better weather, it’s better for our long term health too.
This should be a given as science and our government has long told us that keeping active and regular exercise is good for us. But how much does it help? In an experiment conducted into the longevity of Sardinian men, researchers found that physically and genetically they were similar to their shorter lived Italian cousins, even their diets were very similar. Sardinia has long been famed for the longevity of it’s people so this similarity was surprising. The main difference researchers could ascertain was lifestyle: Sardinian men were far more physically active, and so had stronger, more resilient bodies. Far from discovering a new wonder gene they found healthy, life preserving habits.
This is another given the further you are away from your ideal BMI either lighter or heavier, the less healthy you become. If you are too light that could indicate fragility, too heavy places undue stress on your heart and other internal organs, can worsen arrhythmias, lead to high blood pressure, heart failure, diabetes etc.
For more muscular individuals the BMI index can be unhelpful, but understand that past a certain point, muscle is about as good for you as being overweight is in terms of longevity, due to not just the added weight, but the high metabolic rate of muscle tissue. Don’t let that put you off hitting the gym, adding muscle is great for your overall health and longevity, just think more athletic and less Mr Olympia.
For our size humans are extraordinarily efficient burning only half the calories as another mammal of similar size, and it has been argued that this has contributed to the relatively long lifespans of primates in general. Max Rubner’s rate of living theory states that in essence, the faster an organism’s metabolic rate, the shorter it’s lifespan. Although this theory has come under criticism, it could be theorised that smaller humans with less demanding metabolic needs have an advantage in terms of lifespan.
Continuing this theme compare Wilt Chamberlain, who was 7ft 1 and died at age 63 to the aforementioned Jeanne Calment who was a mere 4ft 11 dying at 122. In fact most centenarians are short, the average is 5ft 1 to 5ft 4. On the other hand men taller than 6ft 4 average a 64 year lifespan.
Assuming good health, shorter people are less likely to suffer from age-related chronic diseases and more likely to reach advanced ages. This is due to reduced cell replication, much lower DNA damage and reduced cancer incidence. All of this essentially comes down to numbers, taller people have more cells than shorter people, therefore they have a higher chance of something going wrong with said cells and DNA.
This is something most of us do not want to hear, but it has been proven in numerous scientific experiments that caloric restriction of up to 40% of maintenance calories results in an increased lifespan in numerous animal species. Clive McKay conducted one of the first experiments into this theory in 1935. He found that severely restricting calories in rats resulted in a 33% increase in lifespan!
The explanation for why ties back into the previous couple of paragraphs, caloric restriction reduces metabolism, reducing rate at which everything in the body occurs, including the rate of internal damage that occurs as part of aging.
This damage is caused by free radicals, highly reactive atoms or molecules our body produces naturally that can damage DNA, proteins and fatty tissue. Free radicals are thought to cause or contribute to age related diseases such as heart conditions, neurodegenerative disorders and cancers. So the slower the metabolic rate, the slower the rate at which free radicals are produced, and potentially the longer an individual’s lifespan.
Some of this is common sense, for example eating whole foods. The reason for this is that you want the food as close to its natural state as possible so you can get the most nutrients from it, think of a Dorito versus an orange, which do you think is better for you?
Beyond that the Mediterranean diet has always been the gold standard when it comes to healthy eating. In a 2018 study, risk of combined heart attack, stroke, and death from heart disease was lowered overall by around 30% for participants consuming a Mediterranean style diet.
A Mediterranean diet borrows traditional eating habits of countries bordering the Mediterranean Sea. It incorporates a lot of fruit, vegetables, legumes, nuts, beans, cereals, grains, fish, and unsaturated fats such as olive oil. This diet differs from most Western diets in that there is less emphasis on meat and dairy products which are consumed less frequently.
Red and processed meat has been associated with an increased risk of coronary heart disease and bowel cancer if consumed in excess so practice moderation and aim to reduce your intake over time.
Whilst the study of genes that determine longevity is a relatively new field it is suggested that 25% of lifespan is determined by genetics. Many supercentenarians possess variants of genes that are associated with longevity.
Some variants are involved in maintenance and function of the body’s cells. These functions include DNA repair, Chromosome maintenance, and protection from free radicals. Other genes are associated with lipid (blood fat) levels, inflammation, and the cardiovascular and immune system. These genes reduce the risk of heart disease, stroke, and insulin resistance. If you have these genes…lucky you!
This affects us both physically and psychologically and is something that can significantly reduce lifespan. Stress and anxiety can double a woman and triple a man’s chance of dying prematurely from heart disease, a stroke or cancer. Pessimists have a 42% higher chance of premature death compared to optimists, so always look on the bright side!
Having an active sex life is great for longevity, it can help with stress reduction, headaches, hormone levels and general pain reduction, as well as reducing the risk from several cancers…and its fun!
Probably one of the most important things on this list and maybe something that we don’t often think about, but after you retire, what then? You have to keep finding new goals and projects to keep yourself occupied, purposeless people are almost twice as likely to die as those with a goal.
This can be a somewhat uncomfortable truth, but with age isolation can increase, friends and relatives move further away, people die, children leave to start their own families. Older people with good social relationships have a 50% greater chance of survival compared to those who don’t have good relationships or are isolated.
This is something seen in long-lived communities such as the Abkhasia people of Caucasia, they don’t just have good relationships with their elders: they treasure them. Growing old among the Abkhasians is something to look forward to rather than fear, a concept totally alien to our society. We spend billions every year trying to mask the passage of time through our lives, imagine the lessening of stress, anxiety, and insecurity that might arise from acceptance of age.
Is it worth it?
One thing that is often overlooked in the case of the very old, is what they think about living so long. In many cases extremely long lived people are found in regions of poverty and simple living. This leads to a hard life, if a long one, surviving rather than thriving. Caloric deprivation in particular, outside of a weight loss diet, is not something many would want to endure for a prolonged period of time.
A good example can be found in China. A village called Bama became famous for the longevity of it’s people, with a considerable population of centenarians. The village became a tourist attraction with many believing in the healing powers of its water. The elderly began to profit from tourists bringing them gifts and money, they no longer had to work and were no longer half starved, they moved less and ate more, particularly expensive meats such as braised pork.
The life expectancy in the village dropped, as it slowly took on the customs of the rest of the world. The tourists destroyed their fountain of youth, but the villagers struck gold. One elderly resident observed, “I have had a lot of happy times, but the best is now”, after all it is not just about how long you live, quality of life is important too.
Can we live forever?
So far we’ve covered genetic factors and healthy habits, but what else is there, these things can optimise life, but not extend it indefinitely. Living forever is beyond the grasp of modern science, but there are companies planning to optimise health further, which could significantly increase your chance for a longer life.
AgeX Therapeutics is concentrating on the potential of pleuripotent stem cells, cells with the ability to produce any other cell or tissue the body needs. This has massive implications for us, stem cells could be used to replace damaged cells for example, not just in terms of fighting aging but injuries: imagine the wheelchair bound able to walk again or regrowing an amputee’s arm, healing a damaged heart etc.
resTORbio is researching a drug designed to inhibit the mTOR pathway, which regulates cellular activity in the body. Decreased TOR activity could increase lifespan according to the company as well as, “ enhance immune function, ameliorate heart failure, enhance memory and mobility … and delay the onset of aging-related diseases.”
Selphagy Therapeutics is attempting to increase autophagy in the body, the process by which damaged cells are cleared out of the body to allow healthy ones to regenerate.
As the science improves the longevity business could well become one of the next great industries, in the UK 70% of the nations household wealth is held by those over the age of 50. In a survey conducted by the Pew Research Center, nearly 70% of adults wanted to live to 100, an eager, vast and rich market.
So whilst technology is improving we can’t live forever just yet, but if you live a healthy lifestyle and invest in the longevity industry you have a good chance of living a very long life indeed.