Property was one of the fastest growing assets in self-managed superannuation fund portfolios during the year to June but its growth was not fuelled by an explosion of borrowing, the latest Australian Taxation Office figures show.The ATO released a June quarter SMSF statistical update this week, reporting that borrowings of SMSFs rose 5.1 per cent to A$9.7 billion during the year to June. Those borrowings were equivalent to 1.7 per cent of the total SMSF assets.The bulk of these borrowings ($8.7 billion) were classified as limited recourse borrowing arrangements, which is the approved form of investment gearing for trustees of self-managed funds. LRBAs grew by just 1.6 per cent in the year to June.Taking only LRBAs into account, borrowings were equivalent to 1.6 per cent of total SMSF assets.Assets have grown at a much faster rate than borrowings - up 12.5 per cent to $557 billion over the 12 months to June.Investment in residential real property grew by 14.7 per cent to $19.5 billion and investment in non-residential real property also grew by 14.7 per cent to $64.9 billion. This growth is a combination of revaluations and new asset purchases.The biggest asset holdings in self-managed funds were Australian shares ($177.6 billion) and cash and term deposits ($157.8 billion).The Financial System Inquiry has received plenty of advice from the opponents of borrowing in super funds who warn that SMSF trustees risk being enticed into the hot housing market by spruikers marketing inappropriate gearing packages. The evidence suggests this is not happening.