The buying power of the aged pension is falling short of the rising cost of living, leaving many older people facing a creeping financial shortfall.

In submissions to a Senate inquiry, welfare groups say rising grocery and utilities bills hurt pensioners more than they do the rest of the population.

This is because groceries and utilities chew up a bigger proportion of the household budget of pensioners than they do for younger households. "Older Australians who feel the consumer price index is not reflective of the cost pressures they are experiencing day-in day-out are probably right," the St Vincent de Paul Society said.

Despite many retirees enjoying windfalls from superannuation, the submissions spotlighted a host of difficulties faced by older people. The Australian Families Association said there was anecdotal evidence retirees were giving the bulk of superannuation payouts to their children to help them buy property.  

Submissions noted older people were taking increased responsibility for grandchildren because working parents were unable to afford child care.

Pensioners were being hurt by rising inflation, the submissions said, despite the pension being linked to the consumer price index. Cheap imports of electronic goods and clothes have helped to keep inflation down, but pensioners spend the bulk of their income on food, utilities and health care, where costs have risen sharply. Aged pensioners spend 57 per cent more on utilities as a percentage of their total consumption compared with the average household and 30 per cent more on food.

Faced with rising utilities bills, older people could cut down on on heating to save money, which would lead to substantial health risks, a submission by the Superannuated Commonwealth Officers' Association said.

Adding to the risks, rising costs of staple foods could result in compromised nutrition.