What does this mean for us? The researchers suggest we need to be really upping our fibre game and aiming for 25-29g of fibre a day; in line with public health recommendations. Most of us, though, get much less than this; around 20g.
Out of interest, I tracked my fibre intake last week. It was interesting to note that it was tricky, for me anyway, to get to the magic 30g mark without making sure to get fibre from a wide range of sources. In other words: not just vegetables and fruit, but also legumes, nuts, seeds and grains.
Oats and chia seeds for breakfast gave me a fibre boost, as did high-fibre vegetables like broccoli and eggplant. My favourite legumes - lentils and edamame beans, plus snacks of home-made popcorn and the grainiest of breads helped. If I had a lower-carb day - not something I particularly aim for, but sometimes just happens - my fibre intake trended down, even if I also ate lots of veges.
The target of 30g fibre has potential implications for those following low-carb or grain-free diets. Study co-author Professor Jim Mann notes it would be difficult to get higher levels of fibre in a very-low-carbohydrate diet, although the study does note that "a range of [carbohydrate] intakes is acceptable".
Whether we're eating low carb or not, it's worth paying attention to one of the main points the study emphasises: the importance of getting our fibre from whole foods.
We can't take a shortcut with fibre supplements; we don't know if they have the same benefits as whole, fibre-rich foods. And cereals labelled "whole grain" but which are processed into shapes probably don't have the same benefit as whole foods that require proper chewing.
We're best, it seems, to get our roughage the old-fashioned way.
• Niki Bezzant is editor-at-large for Healthy Food Guide www.healthyfood.co.nz