A widespread survey has revealed the average Australian eats more than three times the recommended amount of junk food every year.

The CSIRO Healthy Diet Score ranked more than 40,000 Australians out of 100 over their diet and eating habits, and found the average score was 61 – a very poor result.

Women, however, tended to improve their nutritional intake as they get older, and at an average score of 63, ranked higher overall as a group, while men averaged a score of 57.

“Surprising that there was such a difference. There was a six-point difference, that’s actually quite a lot,” Professor Manny Noakes from the CSIRO told 9NEWS.

The CSIRO survey found the average Australian eats junk food every day. (AAP) (AAP)

With high sugar concentrations and fatty foods the main culprits fuelling the poor results, Prof Noakes said young people had lived up to their reputation.

“Oh the younger age groups definitely did worse, that’s a very well established fact, that younger people particularly in their 20s tend to score particularly poorly, and as people get older they tend to start to think a little more about their health and wellbeing.”

As an occupation, personal trainers checked in at 66.8, one of the more impressive scores, while tradies ranked among the lowest at an average of 55.

The survey assessed people based on the variety of their diet and the frequency and quality of the essential food groups, including vegetables and legumes, lean meats and poultry, and fruit.

“What we’re finding is people are having larger portions of junk food, more often. This type of food is no longer just an indulgence, [it has] become mainstream and Australians are eating it each and every day,” Prof Noakes said.