The Australian biologist David Sinclair (*1969) is a professor at Harvard Medical School in Boston and Director of the Department for Research into the Biological Mechanisms of Ageing.
According to the New York Times, Sinclair is one of the 100 most influential people in the world.
In his book The End of Ageing (original English edition: Lifespan ), published in 2019, Sinclair provides an overview of exciting old and new developments in the field of ageing research.
His provocative thesis is that ageing is not an inevitable fate, but a disease that can be treated today and possibly avoided altogether in the future.
Longevity in brief
- The life expectancy of Homo sapiens has never been as high as it is today. We are living longer, but not better. On the contrary: in the last decade of life, many of us are suffering more than ever from age-related diseases.
- Sinclair emphasizes that the aim of ageing research is of course not to make us suffer even longer at the end of our lives. On the contrary: we should live longer and be healthy and lively for as long as possible.
- Sinclair is convinced that this is already possible today. Although there is still a lack of reliable scientific evidence in many areas, there are already promising individual case reports.
The information theory of ageing - Why do we age?
There are laws of nature such as the conservation laws of physics: conservation of energy, momentum, angular momentum, etc.; in mechanics, Newton's law of force applies: force = mass times acceleration, and the law of gravity, from which the laws of gravity and Kepler's laws of planetary motion follow. But there are none There is no physical, chemical or biological law that dictates that organisms must age. In fact, there are some creatures that seem to be able to resist ageing. One particularly old specimen of Greenland shark that is still alive is almost 400 years old (source: Science). Plants can even grow much older (namely thousands of years).
Sinclair now postulates that all higher organisms (plants and animals) age because they are descended from a common ancestor called M. superstes or «great survivor» (Microvoluta superstes is a small sea snail), which invented a survival mechanism many millions of years ago that is also responsible for ageing. This survival mechanism, which has constantly evolved over millions of years, is not one reason why we age, but the reason - the only reason!
How does this survival mechanism work? For various reasons (copying errors, external influences), breaks in the DNA double helix occur repeatedly in all living cells. Put simply, the survival mechanism ensures that the cell concentrates one hundred percent on repair work in the event of DNA damage. In other words, our cells invest the resources available to them (material and energy) either in longevity (repairing damage) or in growth and reproduction, but not in both at the same time!
And what does this have to do with ageing? To put it simply, two fundamentally different types of information are stored in our cells: digital information and analog information. Digital information corresponds to the sequence of base pairs in our DNA - the DNA code. All our cells have the same DNA code.
If the DNA code is identical in all cells, how can it be that there are different types of cells that look different and behave fundamentally differently? For example, there are huge differences between liver cells and nerve cells or between skin cells and muscle cells. The difference is made by the analog information that exists in addition to the digital information: the so-called epigenome.
But what is the epigenome?
Certain sections of DNA (known as genes) can either be switched on or off. Liver cells behave differently from nerve cells because different genes are switched on or off in each case. Incidentally, there are more than 200 different cell types in the human body.
To put it simply, genes are switched off by blocking them.
Now comes the crucial point: the protein that switches off the genes by blocking them is the same protein that is also responsible for repairing the damage to the DNA.
The more DNA breaks there are, the more often the genes that should actually be switched off are temporarily switched on. As a result, the corresponding cell loses its differentiation, i.e. it forgets what kind of cell it is. According to Sinclair, this is exactly what ageing is.
The proteins or enzymes that block the genes are called sirtuins. We might not age at all, or at least much more slowly, if our sirtuins didn't have two jobs to do at the same time. And if we could get the cells to produce more sirtuins, we could possibly slow down ageing. We could achieve the same effect if we could get the existing sirtuins to work faster.
In fact, the ageing of living organisms even seems to accelerate over time, which Sinclair explains by the fact that the sirtuins increasingly run out of fuel with increasing age. The fuel of the sirtuins is called nicotinamide adenine dinucleotide (NAD). If we could raise the NAD level in our cells, our sirtuins would work more reliably and we would age more slowly.
How NAD amplifiers can slow down aging
Even before the discovery of sirtuins, ageing researchers had found out in animal experiments that ageing can be slowed down by certain stimuli. The following measures are also likely to have an effect on us humans:
- Certain forms of physical exercise
- Restriction of calorie intake (calorie restriction) and temporary fasting (intermittent fasting)
- Low protein diet
- Heat and/or cold
Unfortunately, exercising, starving or freezing is exhausting and/or uncomfortable. Fortunately, Sinclair and other scientists have found evidence that ageing can possibly be slowed down with much less effort: Certain substances could improve the efficiency of sirtuins by raising NAD levels in cells. One such substance is nicotinamide mononucleotide (NMN). After feeding NMN to old laboratory mice, they not only became measurably more lively, but also lived longer.
Another hot candidate is the (prescription) diabetes drug metformin. Metformin appears to activate several anti-ageing defense mechanisms, including the sirtuin SIR1. Studies found that diabetes patients treated with metformin were significantly less likely to develop a whole range of diseases, including certain types of cancer. The lifespan of mice given metformin was extended by as much as six percent. The so-called TAME study is currently underway, the aim of which is to find out whether metformin can achieve a measurable benefit in older people who do not suffer from diabetes.
The substance resveratrol, which is found in red wine, apparently also makes sirtuins work much faster. The lifespan of yeast could be extended with resveratrol. However, from the fact that resveratrol had no (additional) influence on the lifespan of yeast when their calorie intake was restricted, it was concluded that resveratrol and calorie restriction activate the same reaction pathway. In animal studies, resveratrol made mice live 20 percent longer and offered them protection against a whole list of diseases.
As long as the placebo-controlled double-blind studies in humans have not been completed, it would be dubious to claim that NMN, metformin and resveratrol prolong people's lives.
Practical advice from the author
If you follow the idea of Longevity then, in my opinion, you should integrate the following concept into your life:
- Daily intake of NMN, substitution of the most important Antioxidants, minerals, trace elements and vitamins (including vitamin D with vitamin K 2 )
- Substitution of bioidentical hormones by laboratory (see: Effects and benefits of bioidentical hormones)
- Adhere to intermittent fasting according to the 16:8 method
- Eat a keto-oriented Mediterranean diet with lots of vegetables, fruit, nuts and only a few animal proteins (see separate article)
- Sleeping in cool surroundings
- Walk a lot, take the stairs instead of the elevator, exercise (alternate between weight training and jogging at least 3 times a week), practice yoga with breathing exercises every day, go to the sauna as often as possible followed by a cold bath or take a Kneipp walk
- Make regular visits to the sea and/or thalassotherapy
- Have regular blood tests (more information from the author)
- Avoidance of
- Smoking
- Sugar, bread, pasta and other carbohydrates
- Meat
- Ready meals from the microwave (because of the radiation)
- UV radiation, X-rays and CT scans (ditto)
About Dr. med. Andreas Bernhardt:
Dr. Bernhardt is a specialist in general internal medicine with international training in endocrinology and Better Aging. He is a member of the Swiss Anti-Aging Society (SSAAMP) and the renowned Endocrine Society (Washington, D.C.). His focus is on bioidentical hormone therapy as part of a holistic longevity concept. As an expert on the German-speaking platform wechselweise.net he is committed to raising awareness in the DACH region about hormonal changes in men and women during the menopause - with the aim of promoting health and quality of life in the long term.