Three quarters of Ireland's over-50s are overweight or obese, new research shows.
Tests revealed many have suffered from undetected clinical diseases or high blood pressure, with one in 10 showing significant symptoms of depression.
But the study revealed pensioners aged between 65 and 74 were the happiest people as the country plunged in to a deep recession.
Some 8,500 men and women aged over 50 were quizzed about their health, financial circumstances and quality of life over the last two years as part of The Irish Longitudinal Study on Ageing (TILDA).
Blood tests taken from more than 6,000 of them during health assessments will be stored and could also help scientists of the future spot the early signs or causes of diseases such as dementia.
Professor Rose Anne Kenny, principal investigator of TILDA, said the importance of the study - to be carried out every two years until 2018 - cannot be overstated.
"By collecting and analysing this data, we will be able to develop a much deeper understanding of the lives and circumstances of older people and of the factors which lead to good health and good quality of life in older ages," she said.
"This will mean that Ireland will be better placed to plan for the ageing of our population and to help policy makers ensure that limited resources are correctly targeted to those in needs."
Researchers said social care was failing parts of the population, just 3.5% of over-50s getting state home help services.