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).
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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.
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Anti-ageing medicine aims to extend healthy lifespan (healthspan). It aims to detect, prevent, treat, and reverse age-related dysfunction, disorders, and diseases. 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.
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Ageing as a Disease Risk Factor​
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.
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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 regular part of ageing. Cognitive loss, for example, is not a natural consequence of getting old, though many people believe that it is.
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Biological Age vs. Chronological Age
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 assigned each a biological age based on a range of biochemical markers, which ranged 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.
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Theories and Mechanisms of Ageing
We all know the outward signs of ageing: wrinkles, grey 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. There are likely many underlying processes, and several theories have been proposed. Better-known historical theories have included simple wear and tear and oxidative stress.
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Recently, the best evidence comes from single-gene mutations shown to affect animal lifespan. Human studies have confirmed the heritability of longevity, with centenarian studies showing that their offspring are genetically protected against age-related diseases. However, we have recently become more aware of epigenetics, in which lifestyle alters genes for better or worse, and we cannot look at genes in isolation.
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There is also much 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. In animal studies, stress, such as intermittent fasting or exercise, increases 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.
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The hormone theory of ageing is based on the fact that the endocrine system changes with age. These changes cause a loss of bone and muscle mass, memory, and strength, along with an increase in fat mass. Research has shown that menopause accelerates cellular ageing by an average of 6%. Hormone replacement therapy can be used to prevent some of these changes and improve quality of life; however, there are risks, and there is insufficient evidence of an extended healthy lifespan in humans.
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Advanced Anti-ageing Health Checks
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 is diagnosed, which is often not assessed in routine health checks, missing the chance to intervene. We aim to identify this early, when we can reduce blood glucose with lifestyle or drug interventions and prevent the adverse effects of raised blood glucose.
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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.
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Once results are available, additional testing may be required, such as toxin testing, gut health testing, coronary vessel assessment, or genetic testing. Biological age and risk factors are discussed, and advice given on modifying them through lifestyle, diet, exercise, supplements, and, if indicated, medications.
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Promising Anti-ageing Medications and Supplements
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 that people with type 2 diabetes were getting less cancer than those in the general population, and studies confirmed a 40% risk reduction. Animal studies followed, showing a 40% increase in lifespan. The FDA has approved a human study into the anti-ageing effects, and the majority of physicians in the anti-ageing field (including myself) have been taking this drug for over a decade.
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Another compound of interest is NAD+, which has shown promising results in animal studies. However, I would exercise caution before taking large doses of this supplement without a physician’s support, as it can interfere with methylation, an essential process in every cell. Up to 50% of the population has methylation defects, which can affect neurotransmitter balance.
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Ongoing research has also demonstrated that dietary polyphenols, such as resveratrol and curcumin, can protect against age-associated disorders through various mechanisms. They appear to mitigate age-associated cellular damage induced via metabolic production of reactive oxygen species (ROS). Common foods that contain these include red wine, green tea, curry spices, and olive oil. They are proposed to explain the benefits of the “Mediterranean Diet”
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Conclusion: Exercise as a Potent Anti-ageing Tool
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 potent anti-ageing tools we have is exercise. Multiple studies have proven that people who exercise throughout middle age live an average of 10 to 15 years longer. This is because exercise prevents a multitude of diseases, including cancer, hypertension, and diabetes.
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By Dr Salmond