Almost seven in 10 Australians are now considered overweight or obese, after a rapid growth in the number of young adults stacking on too much weight.

The Australian Bureau of Statistics revealed on Wednesday that within just three years there had been 18 per cent jump in the proportion of those aged 18 to 24 judged to have an excessive BMI.

While this group is traditionally much slimmer than the rest of the population, 46 per cent are now considered overweight or obese, up from 38.9 per cent in 2014-2015.

More Australians are facing problems with obesity earlier in life.

Today, the typical Australian man weighs 87 kilograms and with an average height of 175 centimetres is deemed overweight, according to the ABS’ National Health Survey.