Longevity Medicine
Anti-ageing, the future of medicine?
People are living longer – in Hong Kong alone, life expectancy has increased by 8 years in the last 30 years (Hong Kong boasts the highest life expectancy in the world).
Whilst all of us would like to live longer with a good quality of life, few of us wish to extend years living with mental or physical disability.
The aim of anti-ageing medicine is to extend healthy lifespan (healthspan). It’s aim is to detect, prevent, treat and reverse age related dysfunction, disorders and disease. It is a relatively new medical field which has grown increasingly relevant with the burden of mental and physical disease and disability in the elderly with rising longevity.
Although ageing isn’t yet classified as a disease, it is the primary risk factor for developing many chronic diseases, including cardiovascular disease, diabetes, dementia, and cancer. In turn, many of these conditions hasten the ageing process, setting up a vicious cycle of cellular damage and loss of function.
However, while those diseases become more common as people age, not every ageing person acquires them. There are also many misconceptions about what is a normal part of ageing. Cognitive loss, for example, is not a natural consequence of getting old, though many people believe that it is.
We have all noticed that some people seem to age faster than others and one study looked into why. They assessed a large group of 38 year olds and gave each a biological age using a range of biochemical markers which was found to range from 30 to almost 60 years. When analysing common factors in those with younger biological than chronological age the results were not surprising, It was things like not smoking, not drinking heavily, eating more plant-based food, exercising regularly, having a higher socioeconomic status, having lower stress, and getting enough sleep. Further research showed that those with higher biological age died much younger. Interestingly those with lower biological age were also rated as looking younger and vice versa.
We all know the outward signs of ageing: wrinkles, gray hair, loss of muscle bulk, a stooped posture and deterioration in mental function. However we do not yet fully understand the complex interplay of factors that cause us to age as we do. It is likely that there are a multitude of underlying processes, and a number of theories have been proposed. Better-known historical theories have included simple wear and tear and oxidative stress.
Recently the best evidence lies in the existence of single-gene mutations that have been proven to affect the lifespan of animals. Human studies have confirmed the heritability of longevity with studies in centenarians showing that their offspring are genetically protected against age-related diseases. However we have recently become more aware of epigenetics, where lifestyle alters genes for better or worse, and we cannot look at genes in isolation.
There is also a lot of recent interest in proteins called sirtuins which regulate cellular health. They need NAD+ (nicotinamide adenine dinucleotide) to function and levels of this have been proven to reduce with age. From animal studies stress such as intermittent fasting or exercise raises levels of these essential proteins. Studies in humans have confirmed that those who exercise through middle age live 10 to 15 years longer and animal studies have shown significant extension of lifespan with intermittent fasting. The theory is that exercise or fasting triggers longevity genes to repair your body.
The hormone theory of ageing is based on the fact that the endocrine system changes with age. These changes cause the loss of bone and muscle mass, memory and strength together with an increase in fat mass. Research has shown that menopause speeds up cellular ageing by an average of six per cent. Hormone replacement therapy can be used to prevent some of these changes and improve quality of life however there are some risks involved and there is not enough proof of the extension of healthy lifespan in humans.
In the practice of anti-ageing medicine we start with an advanced anti-ageing health check. This is different from most routine health checks in that in addition to identifying current disease it also looks at many risk factors for future disease, signs of which can be seen as early as the teens.
One example is type 2 Diabetes which we know hastens the onset of many diseases. Much of the damage is caused in the prediabetic phase well before diabetes would be diagnosed, which is often not assessed in routine health checks missing the chance to intervene. We look to identify this in the early stages when we can reduce blood glucose with lifestyle or drug interventions and prevent the adverse effects on the body of raised blood glucose.
During the health checks we look at medical history, current health and lifestyle, family history, physical examination and laboratory studies to assess current wellness and risk factors for future disease and disability.
Once results are available additional testing may be required such as toxin, gut health, coronary vessel assessment or genetic testing. Biological age and risk factors will be discussed and advice will be given on modifying these with lifestyle, diet, exercise, supplements and medications if indicated.
Trials are currently underway on several possible anti-ageing drugs. The best evidence lies with a cheap and safe drug called Metformin which is a diabetic drug available for 60 years and interestingly similar to a traditional plant, Galega officinalis, used going back to the middle ages for controlling blood sugar.
It was initially noticed people on this for type 2 diabetes were getting less cancer than those in the general population and studies confirmed a 40% risk reduction. Animal studies followed showing an extension in lifespan of 40%. The FDA has approved a human study into the anti-ageing effects and myself and the majority of physicians in the anti-ageing field have been taking this drug for over a decade.
Another compound of interest is NAD+ which has shown promising results in animal studies. However I would exercise caution in taking large quantities of this supplement without physician support as it can interfere with methylation which is an important process in every cell. Up to 50% of the population have methylation defects and it can affect the neurotransmitter balance.
Ongoing research has also demonstrated the ability of dietary polyphenols such as resveratrol and curcumin to protect against age-associated disorders. through a variety of mechanisms. They appear to mitigate age-associated cellular damage induced via metabolic production of reactive oxygen species (ROS). Common foods containing these include red wine, green tea, curry spices and olive oil. They are proposed to explain the benefits of the “Mediteranean Diet”
In conclusion, we know of many factors which increase the risk of future disease and many interventions that prevent disease. Whilst searching for the “fountain of youth” we must not forget that one of the most powerful anti-ageing tools we have is exercise. Multiple studies have proven that people who exercise through middle age live an average of 10 to 15 years longer. This is due to the fact that exercise prevents a multitude of diseases, examples of which are cancer, hypertension, diabetes.