The present paper reviews progress in research on dietary fibre and human health over the past five decades. There is now convincing evidence from prospective cohort studies that diets low in dietary fibre are associated with increased risk of common non-communicable diseases including CVD, type 2 diabetes and colorectal cancer. These findings provide strong support for hypotheses proposed by Denis Burkitt 50 years ago, based on very limited evidence but with considerable imagination and insight. For the first two to three decades of this period, research on dietary fibre was hampered by the lack of consensus about the definition, and measurement, of this complex and diverse dietary component and by the lack of appropriate tools for investigating the gut microbiome that is central to understanding mechanisms of action. Recent technical and scientific advances in microbiome research (based on fast, low-cost, DNA sequencing) are facilitating investigation of the associations between dietary fibre, the gut microbiome and human health. Current challenges include the need for agreement about the characteristics of a healthy gut microbiome. Although the health benefits attributed to higher dietary fibre intake are likely to be shared with most types of dietary fibre, one should anticipate that different sources of dietary fibre and the other components (resistant starch and non-digestible oligosaccharides) that make up dietary fibre will have characteristically different effects on human physiology and disease risk. In conclusion, population-level intakes of dietary fibre are low and there is a public health priority to develop and implement more effective interventions to increase intake.

Genetic risk is particularly salient for families and testing for genetic conditions is necessarily a family-level process. Thus, risk for genetic disease represents a collective stressor shared by family members. According to communal coping theory, families may adapt to such risk vis-a-vis interpersonal exchange of support resources. We propose that communal coping is operationalized through the pattern of supportive relationships observed between family members. In this study, we take a social network perspective to map communal coping mechanisms to their underlying social interactions and include those who declined testing or were not at risk for Lynch Syndrome. Specifically, we examine the exchange of emotional support resources in families at risk of Lynch Syndrome, a dominantly inherited cancer susceptibility syndrome. Our results show that emotional support resources depend on the testing-status of individual family members and are not limited to the bounds of the family. Network members from within and outside the family system are an important coping resource in this patient population. This work illustrates how social network approaches can be used to test structural hypotheses related to communal coping within a broader system and identifies structural features that characterize coping processes in families affected by Lynch Syndrome.