Eat better, live longer!
15 March 2011
The weight of time is not the same for everyone. While muscle strength, autonomy, perception capacities or cognition start diminishing in some people at the moment they reach the “senior” category, others look set to reach a hundred years. Can science give us the keys to this longevity? Not yet, but it is starting to shed light on certain underlying mechanisms.
First fact: the quality of ageing is closely linked to lifestyle habits. And these become increasingly important as we grow older. But what do we mean by lifestyle habits? When we talk of ageing, five factors come under the spotlight: lack of exercise, hypertension, obesity, diabetes and smoking. It is however difficult to determine the impact of each of these when they are combined in one individual. It is for instance probable that someone who exercises regularly and has an optimum weight, does not smoke or suffer from diabetes.
However, one factor stands out from the rest: nutrition. The various studies agree on this point, namely the widespread notion that healthy, balanced eating habits are the password, or at least one of the keys, to a successful ageing process. So what is the recipe for retiring in good health? A high intake of fruit, vegetables, potatoes, wholegrain cereal, dairy products, and food that is rich in omega-3 fatty acids, together with low alcohol consumption.
To play it safe, must one also try and restrict calories? Since the end of the 1980s, various studies have indeed shown that a reduced energy intake in various mammal species significantly increases life expectancy and holds back the onset of age-related diseases. Deducing from this that you merely need to eat less to live longer is an easy conclusion… not to be jumped to. Or at least, not without caution, and not at any age. It is a bad idea to be a picky eater when your body is vulnerable, whether it’s due to an advanced age or to stress or illness. Maintaining eating habits that are adequate in quality and quantity remains essential if we want to make sure we are getting enough protein, vitamin D, E, C and B9, which are all indispensable allies for a weakened body. However when a diet is followed in a favourable context, in other words while maintaining an appropriate body weight, getting regular exercise and living in a healthy environment, it can only be beneficial.
But though our knowledge is improving, prompted by the interest that this field of study draws, longevity still retains some of its mystery. Through which mechanisms does calorie restriction improve the ageing process? What role do fatty acids in food play? What is the ideal weight to aim for when you grow older? Many questions remain… And listening to what those who’ve reached a hundred have to say, the road to a long life is not always a straight one…