“Healthy diet” bad for old people

75-year-olds lose muscle mass on “healthy diet”, leading to possible loss of quality of life according to research from University of Auckland’s School of Population Health.

Bread is an important protein for older people to help guard against muscle and mobility loss and deteriorating quality of life, according to a leading study about living beyond 80 in New Zealand.

Professor Ngaire Kerse, from the University of Auckland’s School of Population Health, co-leads the study – known as LiLACS NZ – which measured food intake in octogenarians, establishing bread as a surprisingly important source of protein for that age group (ranked only after meat and milk).

Bread is often demonised in diets and health-conscious conversations everywhere, says Professor David Cameron-Smith, whose own new research highlights just how vital protein-rich food is for elderly people.

Yet the so-called “healthy diet” was not enough to stop a group of 75-year-old healthy men from losing muscle mass in a 10-week experiment.

It is, says Cameron-Smith, an oversight that helps to make people old before their time.
Cameron-Smith, professor of nutrition at the Liggins Institute, a much-respected research arm of the University of Auckland, is involved in ongoing research on the effects of nutrition in elderly people and says: “All our perceived wisdom on healthy diets largely comes from the 1960s, 1970s and 1980s, when the main focus was on heart disease and diabetes.

But the world has moved on now and, as we know, the population is ageing rapidly.

“What we discovered in our research is that the diet guidelines formed in those past decades do not cover the whole field. The world is shifting gear and an ageing population is transitioning into old age – but the diet guidelines we hold dear do not apply to older people,” he says.

The key was protein; the trial measured what happened to the 75-year-olds when they were fed protein and other food groups in accordance with approved dietary guidelines.
“When older men consume a controlled diet containing protein at currently recommended levels, an observable loss of appendicular lean mass [the muscles that, for instance, control movement] can occur in as little as 10 weeks.

“Higher protein diets may be needed to support the maintenance of muscle mass in older adults,” says Cameron-Smith.

Research is continuing but he says the trial showed “the relationship between what is happening now [in terms of diet and health] and the 10-20-30 years before people transition into old age has simply not been considered. Baby Boomers, in this sense, are the forgotten generation.”

Protein was vital in helping to maintain or build muscle mass, which helps mobility, which helps overall health and quality of life. Yet the research showed normal diet guidelines are simply not enough to stop old people losing muscle mass.

He says other population and health research is showing our most vulnerable people are the elderly who live alone and those in nursing homes or care facilities: “A lack of mobility can drastically alter quality of life – and impaired mobility is often the precursor of functional decline, disability and loss of independence.”

That’s where white bread comes in, though Cameron-Smith rates it third behind meat and dairy as a source of protein, adding: “We know protein does relate to health in this age group – and we have to think laterally or inventively about where protein comes from. A couple of slices of toast could help keep older people on the merry…”

Other research being undertaken by the institute and partners involves working closely with organisations like Fonterra, exploring the development of speciality proteins specially designed for older age groups, aimed at bone and muscle mass.

“That is important, not just for health reasons, but also for the New Zealand economy – so we can take the next step up the value chain and develop next generation products which apply to a specific segment or segments of the population.

“It’s vital not just for New Zealand – global estimates are about 2 billion people will be aged 65 and over by 2050.”

Cameron-Smith also believes in the power of other non-protein measures. We have yet to fully adopt, he says, the lessons of the Mediterranean diet, the French paradox [a low incidence of coronary heart disease despite a diet rich in saturated fats], diets in parts of Italy, some parts of China and Japan.

He believes cultures which practise eating together at meals produce healthier citizens: “They eat in a communal setting and I believe it is absolutely, fundamentally true they benefit from it. They eat more and more diverse foods; they seem to prosper from sharing food and being and talking together.

“What many people do here – teas on knees in front of television, well, that will slowly kill you.”