More about Lifespan and Healthspan

As I said last time, the crucial contributors to lengthening Healthspan and reducing the period of poor health at the end of our lives are diet and exercise – both critical lifestyle choices.

Diet

Content: There is some, though often contradictory, evidence that the balance of the different foods we consume plays a part in reducing healthspan – the recommended balance is contained in the so-called Mediterranean diet. This pattern of eating is based on the traditional dietary patterns of people from Mediterranean countries like Greece, Italy, and Spain. It emphasises plant based food, moderate amounts of fish and poultry and limited red meat consumption. Key components include fruits, vegetables, whole grains, olive oil, nuts, seeds and legumes. This diet is thought to beneficially affect various metabolic processes, including lowering harmful blood fats like cholesterol, lowering blood pressure, improving blood sugar control and reducing the risk of heart disease and stroke.

Weight management: However perhaps the most important characteristic of the Mediterranean diet,  in an age of over consumption, is the fact that it much less calorie dense than our modern way of eating. We lean so heavily on processed food which is much more calorie dense. Being less calorie dense means that volume for volume, the Mediterranean diet contains much fewer calories – for a given meal size it is much less fattening. People who eat this diet are therefore much less likely to become overweight. I believe that lessening the risk of being obese is its main virtue.

Exercise/physical activity

The most effective way of prolonging our healthspan is to take adequate exercise. In this respect it is far more effective than diet. The main mechanisms include:

Increased physical fitness: Just keeping fit helps to maintain the ability to care for oneself. This does not matter to someone in their forties but can be critical to someone in their eighties or nineties. Physical fitness declines declines steadily from about the age of 20 till you meet the grim reaper. Your fitness level, measured by VO2max, falls by about 1 to 2% per annum and a bit more rapidly after the age of 70.  The rate of fall depends on how much exercise you take. If at 20 you have an average VO2max of 50, by the age of 80 it will be between 8 and 27, depending on how much exercise you take. This may make the difference between being able to get out of a chair and make a cup of tea, or being able to get up and get dressed unaided and needing help to do so. It may make the difference between being independent or having to rely on carers or a care home. Your fitness level is the most important measure of when you can still claim to be still enjoying your healthspan.

Weight control: Exercise on its own is a very hard way to lose weight but regular exercise throughout life is a very effective way of avoiding becoming overweight or obese.

Lower risk of the non-communicable diseases of later life: These include heart disease, stroke, type 2 diabetes, wear and tear arthritis, dementia, several forms of cancer, Parkinson’s disease and several others. Any one of these may be enough to take you beyond your healthspan. They all further reduce the ability to exercise and lead to a more rapid decline into “terminal morbidity” – those last few years between the end of healthspan and the end of life.

What works better?

Physical activity/exercise had a far greater effect on both healthspan and lifespan than does eating habit – or indeed than any drug therapy. Regular exercise decreases the risk of premature mortality by between 30 and 40%. This equates to some 150,000 deaths per year. Much more important, though, is the effect of regular exercise on healthspan. The evidence is clear that physical activity is required to maximize health span (and lifespan) and the more the better.  The maximum achievable increase in health span from exercise is  attained at between 3-5 times the government’s recommended physical activity level (450-750 min/week) .

There are no accurate figures for how much the period of terminal morbidity at the end of life is shortened by regular exercise but I guess it must be over 80%. Just think what that might mean to the need for carers, care homes and emergency hospital admissions? It is mind-boggling!