The UK's main inflation rate fell back towards the 2% target in August after reversing a surprise jump the previous month.
Higher long-term inflation expectations added £5bn to defined benefit scheme deficits in August, according to Mercer.
The public remains confused about pension indexation almost two-years after the Chancellor reformed it, Aon Hewitt says.
The Consumer Prices Index rate of inflation climbed to 2.6% last month, from 2.4% in June.
The Bank of England has cut its forecast for economic growth this year to almost zero and has predicted inflation will be below target in the medium term.
The Consumer Prices Index (CPI) measure of inflation fell to 2.4% in June, from 2.8% in May, official figures show.
Sponsors will be forced to support schemes for the next five to ten years because the relationship between risk-free assets and inflation is "broken", UBS says.
The UK's inflation rate posted another surprise drop in May, falling to 2.8%, as the lack of activity in the UK continues to bring prices down sharply.
UK pension schemes hedged a record £13.9bn of inflation risk in the first quarter of the year, according to research from F&C.