Carrots growing in the ground

An underrated way to live longer

26 August 2019
Professor Luigi Fontana summarises the presentation that he delivered at the Australian Biology of Ageing Conference 2019.

If people ate well and exercised, hospitals would be 80 per cent empty. This may sound bold, but I have spent my career researching the impact of how we treat our bodies on the incidence of the most common chronic diseases. I have found that despite a view of diseases as suddenly cropping up, they often develop in our bodies over decades. Therefore, they can often be prevented from occurring in the first place.

Heart attacks, for example, are often preceded by the build-up of plaque in arteries. And what causes plaque? Factors include smoking, high cholesterol, glucose, and blood pressure. If we take a further step backwards, it is evident that individual choices can account for the presence of many of these factors.

Another example: lean people have lower levels of inflammation, oxidative stress and insulin. This means that their cells are better at removing waste products; they have increased DNA repair and antioxidant enzymes – molecules that protects cells from DNA and oxidative damage and proliferate less. Taken together, these circumstances lower the risk of cancer.

And – what is one thing heart disease, cancer, dementia, strokes, diabetes and non-alcoholic fatty liver disease have in common? Excessive calorie intake among their sufferers.

Even people who already have such diseases would do well to modify their diets. Though heart disease is the top cause of death in Western countries, patients can increase their life span by, on average, 11 years, if they have optimal cardiometabolic risk factors.

The choice to eat healthily (or not) begins to produce effects as early as pre-natally: an expectant mother’s diet can shape a foetus’ genes through epigenetics. This, in turn, also affects future generations’ predispositions to disease.

Calorie counting and more

Not all calories are equal. As the above heart attack example illustrates, it’s not enough to simply not be overweight. With food, quantity and quality are essential. To optimise our bodily health, we should:

  1. Substitute refined and processed foods with plenty of those rich in vegetable fibre – which helps prevent allergies and autoimmune diseases
  2. Stop eating when we are 80 per cent full
  3. Eat most of our food in a restricted time frame, for example, 10 hours, with a very light dinner
  4. Once or twice a week eat only non-starchy raw or cooked vegetables dressed with extra-virgin olive oil

We should also watch our protein intake: studies have shown that in mice, high-protein diets shorten lifespans.

Exercise is also critical. In fact, in certain ways, it is more powerful than diet, for instance, in lowering insulin resistance. High insulin resistance is associated with Type II diabetes and heart disease. Exercise has a myriad of other benefits, including boosting mood and helping with sleep.

In this era of a climate emergency, we cannot ignore the impact of pollution on our health

Our bodies, others

Whether or not this food-first approach is favoured, our current health system is at breaking point. No doubt, for example, you’ve heard of the ever-lengthening emergency room wait periods.

Managing chronic disease is the also the mainstay of hospitals in other Western countries. In the US, for example, chronic disease accounts for 81 per cent of all hospital admissions; 91 per cent of all prescriptions; and 76 per cent of all physician visits.

But the significance of preventing chronic disease is even broader than that. In this era of a climate emergency, we cannot ignore the impact of pollution on our health. We also must not disregard that excessive beef production endangers our health; directly, through consumption of meat, and indirectly, through particular matter and greenhouse gas emissions from cattle.

So why, then, do we often neglect diet when treating, not to mention preventing disease?

Get corporeal

Aside from preserving, boosting and remedying your physical health; making hospitals more effective; and slowing climate change, food is for thought. Nourishing your cognitive and mental health starts with your diet. The body is just an instrument with which you can develop yourself and grow to your fullest potential – and help others.

As the Dalai Lama reportedly said, “[Man] sacrifices his health in order to make money. Then he sacrifices money to recuperate his health. And then he is so anxious about the future that he does not enjoy the present; the result being that he does not live in the present or the future; he lives as if he is never going to die, and then dies having never really lived.”

Luigi Fontana is Professor of Medicine and Nutrition at the University of Sydney’s Charles Perkins Centre and Faculty of Medicine and Health. He presented his research at the fourth Australian Biology of Ageing Conference, hosted by the University of Sydney.

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