On Aging

I was transfixed the first time I read ‘Life Extension’ by Durk Pearson & Sandy Shaw, back in 1984. I learnt about ‘free radicals’ and their damaging effect on ageing and was introducing to anti-oxidents as a way of combating them.

I was drawn in to the idea that we would extend our lives beyond the present day average. Maybe even living past 100 in a healthy state.

In 1988 I came across Dr Roy Walford’s ‘120 Year Diet’ and discovered calorific reduction (CR).

Roy limited his intake to below1,000 calories a day (the average male is recommended to consume 2,500). He based this on the many controlled experiments on a wide range of animals, from fruit flies to mice, that consistently led to control groups on an extremely low calorie diet living significant longer that those who ate the average intake.

Roy passed away in 2004,  from the auto-immune disorder Lou Gehrig’s disease. He was aged 79, around the average for an educated, middle-class white California male of his generation.

So is life extension discredited?

I don’t believe so. Firstly Roy’s death was caused by a rare disease that is exacerbated by a low-calorie diet.

Secondly,  growing scientific consensus is pointing to the fact that ageing is not inevitable.

The search for eternal youth is a story of con-men and liars peddling a wide range of snake oil elixirs, pills and potions with no possibility of working.

And still, the search continues as we wait for our first 125-year-old.  (The record stands at 122 years – achieved by Frenchwoman Jeanne Calment, who died in 1997.)

 

But the truth remains that medical science is improving healthcare, allowing more of us to reach our potential. Life expectancy is constantly increasing all around the world as infant mortality rates continue to drop because of improved diets, increased prevention of disease and better medicine.

As yet we haven’t conquered age. Increased life expectancy means more and more of us are not having our natural lives shortened by disease or illness.

And yet, almost daily, comes news of interesting medical experiments that may led to a breakthrough. More and more experts now say that science will be able to increase human lifespan.

It’s is believed that medicine will be available to delay serious illnesses, not just to deal with an existing illness, but to guard against it happening in the first place.

This would give us at least five or more extra years of healthy old age and allow the 120 year barrier to be breached again and again.

Until recently, scientists working on increasing the longevity of fruit flies or laboratory mice have admitted their work and those positive results may not work on human genetics in the same way.

However there is now a much wider belief among researchers that it will be possible to influence humans – to improve their genetic structure – in a way to reduce disease and to increase renewal of tissue, muscle and bone.

The science of why humans age has seen big leaps in understanding over recent years. It wasn’t long ago we believed our bodies simply wore out, like machines.

But this can’t be true as our bodies are equipped with efficient repair systems that keep our cells healthy for ­decades.  Ageing is not entirely inevitable. Several organisms appear to hardly age at all and live for centuries.

Humans are among the longest-lived of all species, but our longevity is exceeded by some giant tortoises which can live for nearly 200 years.

Bowhead whales have recently been found, alive and well, with antique harpoons embedded in their skulls which can be dated back to the 1790s. Some of these animals may be more than 300 years old.

According to the Guiness Books of Records, the longest undisputed lifespan for a male is that of Jiroemon Kimura of Japan (1897–2013), who died aged 116 years, 54 days and the longest documented human lifespan is that of Jeanne Calment of France (1875–1997), who died at age 122 years, 164 days.

Nature’s pattern is that big creatures get to live longer than small ones.  Evolutionary theory states that animals age at a rate commensurate to their likely survival time in the wild. Mice age quickly because – being small and feeble – they are likely to be eaten, starve or perish due to cold before too long. It makes no sense for a mouse to be equipped with disease prevention systems if it is likely to be killed by a predator within months of birth.

Evolution therefore ensures a mouse’s body is full of sex hormones so it reproduces before being eaten to ensure the survival of the species.

Elephants age slowly because they are designed to live longer. They can survive long periods of drought and starvation, so they have more advanced disease resistance. In addition they possess complex DNA repair systems to ensure their bodies can self repair, keeping them going for half a century or more.

Large birds also live a long time because they have few predators and good mechanisms for survival. Over time they have evolved to become better able to cope with aging in order to make the most of their expected life span.  For this reasons, a large bird ages much more slowly that a mouse.

 

This is fine in theory, but knowing why we age tells us little about how we age – and even less about what we might be able to do about it.

Now, new advances in DNA analysis – reading the entire genetic codes of organisms – have opened up exciting new areas in ageing research, allowing ­scientists to pinpoint individual genes which may be be responsible for the breakdown in our bodies over time.

The original anti-ageing hope lay on the discovery of free radicals (waste chemicals in our ­bodies). Scientists investigated free-radical neutralisers called antioxidants such as Vitamin C.

They found excessive doses of Vitamin C could increase free-radical damage and hinder the body’s natural repair mechanisms.

In the 1960s at Univeristy Calfornia, Los Angeles, Dr Roy Walford was exploring the potential links between food and longevity. Working with mice, he found that restricting their caloric intake by about 40% could nearly double their life span — but only if the diet was started at a very young age and they consumed a nutrient-rich diet that prevented malnutrition.

The diet preserved both physical health and mental agility. He found that a 36-month-old mouse that had been fed the restricted-calorie diet could run a maze with the facility of a normal 6-month-old mouse.

Calorie reduction to extend life has been replicated in many other tests, with a variety of species, including primates.

Significantly it has been found to work with older animals as long as calorie reduction was introduced gradually.  When experimenters abruptly switched mice to a low-calorie diet, the animals suffered a variety of adverse effects and their life spans were usually shortened dramatically. But Dr Walford found that easing the animals into the diet over a two-month period allowed them to live at least 20% longer.

So Roy Walford decided to become the first human to test calorie reduction, eating fewer than 1,500 colories each day.

He believed his experiment a success, despite dying at the age of just 79.

He considered the onset of ALS began during the 1991 Biosphere 2 test. Biosphere 2, (biosphere 1 being Earth) was a $150-million, 3-acre, glass-enclosed structure built to determine whether humans could live in a self-sustaining environment on another planet, such as Mars. In the enclosed atmosphere, levels of nitrous oxide rose dangerously and began damaging his brain cells by the end of the two year experiment.

He considers calorie reduction increased his lifespan in the face of this disease.

In theory calorie reduction should work for humans. Research points to the fact that extreme calorie restriction switches on a genetic mechanism called a stress response. This has evolved to allow animals to survive tough conditions such as famine and drought.

The bodies of mice – and possibly those of humans, too – react to starvation by boosting their repair mechanisms, triggering anti-inflammatory responses which slow the damage done to vital organs as they age.

Since Roy Walford’s death, two large scale experiments have been carried out on rhesus monkeys. (The rhesus shares about 93% of their DNA with humans).

In the US, the National Instute on Aging (NIA) ended a 20 year study which tested calorie restriction on rhesus monkeys in 2012.  One group of monkeys were fed a healthy diet and the second group recieved the same food, but 30% less of it. The study concluded that the reduced calorie group didn’t show any health benefits over the first group.

The University of Wisconsin-Madison’s National Primate Research Centre’s began an ongoing study in 1989 with 76 rhesus monkeys.  As of 2014 the 38 monkeys that received 30% less food have show signs of better health and longer life span and the 38 monkeys that are allowed to eat what they want.

The leader of the Wisconsin study, Rozalyn Anderson, says her team’s results show that “absolutely, calorie restriction does work.”

Along this study, drug companies have been looking to isolate chemicals that mimic calorie restriction, without having to reduce normal food intake.

A lot of money is currently being spent by the big drug firms on anti-ageing drugs. So it is probable that the future will bring pills to chemically to copy the effects of a near-starvation diet and increase lifespan in humans.

When this happens, the quest will then be to improve the quality of life over a 130 -150 year life span.

There is a big difference between being a healthy 100 year old as opposed to someone the same age, living with dementia and unaware of the world around them.