Harnessing the Magic of the Dairy Matrix for Next-Level Health Solutions: A Summary of a Symposium Presented at Nutrition 2022

Associations between Saturated Fat from Single Dairy Foods and Body Composition in Young Canadian Children

Purpose: To examine the associations between dairy-derived saturated fat from fluid cow's milk, cheese, and yogurt, and body composition [body mass index z-scores (BMIz), fat mass index (FMI), and waist-to-height ratio (WHtR)] in children aged 1.5-5 years. Methods: This cross-sectional study used baseline data from 267 children (3.5 ± 1.2 years) from the Guelph Family Health Study. Dairy-derived saturated fat intake (g/1000 kcal) was assessed via one 24-hour dietary recall completed by parents using the web-based Automated Self-Administered 24-Hour Dietary Assessment Tool 2016 - Canadian version. Linear regression using generalized estimating equations explored associations between dairy-derived saturated fat intake and BMIz and FMI, adjusted for physical activity, household income, parent education, and child ethnicity; WHtR was additionally adjusted for age and sex. Results: Total dairy- and milk-derived saturated fat were not associated with any body composition outcomes. Cheese-derived saturated fat intake was positively, but marginally associated with BMIz (B̂ = 0.03, 95% CI: 0.01 to 0.06, p = 0.013), while yogurt-derived saturated fat was inversely associated with FMI (B̂ = -0.19, 95% CI: -0.34 to -0.04, p = 0.015). Conclusions: These cross-sectional findings may inform dietary guidelines to recognize the neutral or potentially beneficial effects of saturated fat from dairy products on body composition in young children. Longitudinal studies are warranted.

Decrypting the messages in the matrix: The proceedings of a symposium on dairy food matrix science and public health opportunities

Although food matrix research is still in its infancy, there is an emerging understanding of the important role of the food matrix on human nutrition and physiology, as well as for public health. This understanding has largely been propelled forward by research involving different milk and dairy food matrices which has revealed that in addition to their distinct array of nutrients and bioactive compounds, milk and dairy foods also contain complex food matrix microstructures that act as nutrient and bioactive delivery systems that set them apart from the other food groups. Due to these distinct food matrix properties, milk and dairy foods may be uniquely positioned to help Americans meet many of their nutrition and health needs. The aim of this manuscript is to describe the activities and findings from a National Dairy Council-sponsored symposium focused on connecting the science on milk and dairy food matrices with opportunities for improving public health. This proceedings paper summarizes and communicates the symposium presentations and panel discussions, key insights, and next steps to help leverage the evidence on different dairy food matrices (e.g., milk, yogurt, cheese) to develop science-backed strategies to support public health and health equity.

The impact of sex and the cheese matrix on cholesterol metabolism in middle-aged adults

BACKGROUND AND AIMS

Cheese has been shown to lower total and LDL cholesterol concentrations, despite being a source of saturated fat. The dairy matrix is purported to be responsible for this effect. There is increasing recognition of sexual dimorphism in the development and progression of cardiovascular disease (CVD), in addition to sex-related differences in response to nutrition interventions. This analysis aims to explore the effect of sex on the cholesterol-lowering effect of cheese compared to butter.

METHODS

The present study is secondary analysis of pooled data from two parallel-arm randomised controlled trials (RCT) with similar protocols, where participants (n 197, 41.6 % male) received either 120g cheese (n 104) or deconstructed cheese (49g butter, 30g calcium caseinate and a calcium supplement, n 93) for 6 weeks. Each arm provided ∼40g fat per day.

RESULTS

In the group as a whole, cheese was found to lower total and LDL cholesterol, compared to deconstructed cheese. No sex × treatment interactions were observed although, within-sex analysis found men and women to respond differently. Within males, cholesterol concentrations decreased in response to dairy fat. Within the female group cheese lowered total and LDL cholesterol concentrations, whereas deconstructed cheese was found to increase the same lipid markers.

CONCLUSIONS

Cheese was found to lower cholesterol concentrations in the cohort as a whole, while men and women were found to respond differently to dairy fat. Females appear to respond more favourably to cheese compared to deconstructed cheese. These findings indicate the cheese matrix may have a stronger effect in females and thus may play a role in personalised nutrition.

Dairy Consumption and the Colonic Mucosa-Associated Gut Microbiota in Humans-A Preliminary Investigation

BACKGROUND

Dairy consumption has been associated with various health outcomes that may be mediated by changes in gut microbiota.

METHODS

This cross-sectional study investigated the association between the colonic mucosa-associated gut microbiota and the self-reported intake of total dairy, milk, cheese, and yogurt. A total of 97 colonic mucosal biopsies collected from 34 polyp-free individuals were analyzed. Dairy consumption in the past year was assessed using a food frequency questionnaire. The 16S rRNA gene V4 region was amplified and sequenced. Operational taxonomic unit (OTU) classification was performed using the UPARSE and SILVA databases. OTU diversity and relative abundance were compared between lower vs. higher dairy consumption groups. Multivariable negative binomial regression models for panel data were used to estimate the incidence rate ratio and 95% confidence interval for bacterial counts and dairy consumption. False discovery rate-adjusted p values (q value) < 0.05 indicated statistical significance.

RESULTS

Higher total dairy and milk consumption and lower cheese consumption were associated with higher alpha microbial diversity (adjusted p values < 0.05). Higher total dairy and milk consumption was also associated with higher relative abundance of Faecalibacterium. Higher milk consumption was associated with higher relative abundance of Akkermansia. Higher total dairy and cheese consumption was associated with lower relative abundance of Bacteroides.

CONCLUSIONS

Dairy consumption may influence host health by modulating the structure and composition of the colonic adherent gut microbiota.

Bovine dairy products and flow mediated dilation (FMD): a systematic review of the published evidence

PURPOSE

Evidence suggests bovine dairy products may have neutral or beneficial effects on cardiometabolic health, despite being a source of saturated fat. The dairy matrix, the structure and combination of protein, fat, and other nutrients, and how they interact with each other, is purported to be responsible for these beneficial health effects. Whether this relationship extends to endothelial function, as assessed by flow mediated dilation (FMD), remains to be elucidated.

METHODS

Three electronic databases (PubMed, Embase and Cochrane Central) were searched from inception until 5th September 2024. This review included randomised controlled trials (RCT) investigating any bovine dairy intervention which considered endothelial function using FMD in humans with a non-dairy or alternative dairy control.

RESULTS

Of 4,220 records identified, 18 reports from 11 RCT including 508 (53.3% male) participants, examined endothelial function by FMD and were eligible for evidence synthesis. Eight papers reported an improvement, nine reported no effect and one reported a decrease in FMD. The greatest effects were found in those with impaired health at baseline, with whey protein and high dairy intakes observed to be most beneficial.

CONCLUSION

Bovine dairy intake has neutral or beneficial effects on cardiometabolic health. This review demonstrates that this relationship extends to endothelial function as assessed by FMD. Whey protein and high dairy intakes may be most effective, although further high quality RCT in this area are warranted.

Whole milk dairy foods and cardiometabolic health: dairy fat and beyond

Bovine dairy milk is a nutrient-rich matrix, but consumption of full-fat dairy food varieties has been claimed historically to be associated with poorer cardiometabolic health, a notion often attributed to the saturated fat content. However, continued investigation that includes observational studies and randomized controlled trials (RCTs) provide evidence that favorably supports full-fat dairy foods and their bioactive components on cardiometabolic health. This review addresses this controversy by examining the evidence surrounding full-fat dairy foods and their implications for human health. Dairy foods are heterogeneous, not just in their fat content but also in other compositional aspects within and between fermented (e.g., yogurt, cheese) and nonfermented products (e.g., milk) that could differentially influence cardiometabolic health. Drawing from complementary lines of evidence from epidemiological studies and RCTs, this review describes the health effects of dairy foods regarding their fat content, as well as their polar lipids that are concentrated in the milk fat globule fraction. Observational studies have limitedly supported the consumption of full-fat dairy to protect against cardiometabolic disorders. However, this framework has been disputed by RCTs indicating that dairy foods, regardless of their fat content or fermentation, are not detrimental to cardiometabolic health and may instead alleviate certain cardiometabolic risk factors. As dietary recommendations evolve, which currently indicate to avoid full-fat dairy foods, it is essential to consider the totality of evidence, especially from RCTs, while also recognizing that investigation is needed to evaluate the complexity of dairy foods within diverse dietary patterns and their impacts on cardiometabolic health.

[Prospects of dietary fibers food fortification for the treatment and prevention of gastrointestinal diseases: A review]

Epidemiological studies have proven the connection between high consumption of dietary fiber and a reduction in the risk of many diseases. In clinical trials, the possibility of functional regulation of the intestine and intestinal microbiome by dietary fibers has been revealed, which may be significant in certain diseases of the digestive system. This review provides information on the relationship between the physico-chemical properties and functional characteristics of dietary fibers, discusses evidence of the effectiveness of their use in the treatment of diseases of the digestive system, discusses the need to enrich food with dietary fibers.