Dairy product consumption and the metabolic syndrome

Dairy product consumption and type 2 diabetes in an Argentinian population: is there an association?

Introduction

Introduction: dairy products have long been recommended as part of a healthy eating plan, but there is a controversial opinion about whether or not they should be included in the diet of people with type 2 diabetes (T2D). Objective: the aim of this study was to know if there is an association between the intake of total dairy and dairy subgroups and the chance of having T2D, and the status of markers of glucose metabolism. Methods: three hundred and forty-two adult subjects participated in the study. A validated food-frequency questionnaire was applied to establish the dairy intake. Clinical-pathological and anthropometric variables (height, weight, waist circumference and serum concentrations of blood glucose, glycated hemoglobin [HbA1c], high sensitive C-reactive protein [hs-CRP], tumor necrosis factor alpha [TNFα], interleukin [IL] 6 and IL-10) were measured. Consumption tertiles were calculated for each dairy subgroup. Correlation coefficients, multiple linear regression models and logistic regression models were used to assess the relation between dairy product consumption and markers of glucose metabolism. Results: a negative correlation was observed between the consumption of fermented dairy products and IL-10 (r = -0.27, p = 0.0206). Fermented dairy products were inversely associated with blood glucose, and HbA1c. Total dairy intake was positively associated with a lower chance of having diabetes in tertiles 2 and 3 of consumption, in relation to the reference tertile, adjusted for age, smoking habit, and alcohol intake, body mass index (BMI) and dietary variables. Conclusions: with this study, we broaden our understanding of the role of dairy intake in diabetes risk. However, more long-term studies are needed to confirm the associations and explore different confounding factors.

Intake of Animal Source Foods in Relation to Risk of Metabolic Syndrome

Metabolic syndrome (MetS) is a prevalent disorder associated with diabetes and cardiovascular diseases. Lifestyle and occupation can increase the risk of developing MetS. Since dietary pattern is a major component of lifestyle, this study aimed to determine the relationship between consumption of animal source foods (ASFs) and MetS among food suppliers. This cross-sectional study was conducted on 112 male food suppliers. We measured anthropometric indices, body composition, and blood pressure of the participants. Blood biochemistry was determined using 5 mL fasting blood samples. MetS was defined based on the guidelines described by the International Diabetes Federation (IDF). ASF intake, including dairy products, eggs, red meat, poultry, and fish, was assessed using food frequency questionnaires. Overall, 46.4% of participants had MetS. Participants who consumed dairy 3∼5 times/d and more than 5 times/d had lower risk of MetS [odds ratios (OR): 0.18 (confidence interval (CI) 95%: 0.05∼0.62) and OR: 0.20 (CI 95%: 0.06∼0.67), respectively] compared with participants in the lowest tertile. The risk of hypertension was significantly decreased in participants who consumed dairy products >5 times/d [OR: 0.22 (CI 95%: 0.07∼0.67)]. Other ASFs were not associated against the risk of MetS in crude and adjusted models. Our findings indicated that adhering to dairy products can decrease the risk of MetS. Higher adherence to dairy products was also protective against hypertension in these participants.

Metabolic Syndrome-Preventive Peptides Derived from Milk Proteins and Their Presence in Cheeses: A Review

The metabolic syndrome (MetS) is defined as the occurrence of diet-related diseases such as abdominal obesity, atherogenic dyslipidemia, hyperglycemia (insulin resistance) and hypertension. Milk-derived peptides are well-known agents acting against high blood pressure, blood glucose level, and lipoprotein disproportion. The aim of this review are metabolic syndrome-preventive peptides derived from milk proteins which were identified in cheeses. Special attention was paid to the sequences acting as angiotensin converting enzyme (ACE), dipeptidyl peptidase IV (DDP4), and α-glucosidase inhibitors, as well as antioxidative, hypocholesterolemic, antiobesity, and anti-inflammatory agents. Some results of meta-analyses concerning the consumption of cheese and the risk of MetS diseases were also presented.

Dairy foods and health: an umbrella review of observational studies

Evidence on consumption of dairy foods and human health is contradictory. This study aimed to summarize the level of evidence of dairy consumption on various health outcomes. A systematic search for meta-analyses was performed: study design, dose-response relationship, heterogeneity and agreement of results over time, and identification of potential confounding factors were considered to assess the level of evidence. Convincing and probable evidence of decreased risk of colorectal cancer, hypertension and cardiovascular disease, elevated blood pressure and fatal stroke, respectively, was found for total dairy consumption; possible decreased risk of breast cancer, metabolic syndrome, stroke and type-2 diabetes, and increased risk of prostate cancer and Parkinson's disease was also found. Similar, yet not entirely consistent evidence for individual dairy products was reported. Among potential confounding factors, geographical localisation and fat content of dairy have been detected. In conclusions, dairy may be part of a healthy diet; however, additional studies exploring confounding factors are needed to ascertain the potential detrimental effects.

Dairy Product Consumption and Metabolic Diseases in the Di@bet.es Study

To date it is not clear what the role of dairy products is in metabolic diseases like diabetes, obesity, and hypertension. Therefore, the aim of this study is to test the association between dairy product consumption and those pathologies. A cross-sectional study was conducted with 5081 adults included in the di@bet.es study, from 100 health centers around Spain. Food frequency questionnaires were carried out concerning consumption habits, which included dairy product consumption. Logistic regression models were used for the association analyses between the variables controlling confounding variables. Women had a higher consumption of milk, cheese, or yogurt than men (p < 0.0001), but men consumed more sugar dairy products (p < 0.001). People who live in the North of Spain consume more dairy products than those who live in the East. Dairy product consumption was inversely associated with the presence of hypertension regardless of age, sex, geographical region, and body mass index (BMI) (Odds Ratio (OR) 0.743; p = 0.022). The presence of obesity was inversely associated with dairy consumption regardless of age, sex, and geographical region (OR 0.61; p < 0.001). Milk consumption was not associated with diabetes. Our results show that consuming dairy products is associated with a better metabolic profile in the Spanish population.

Importance of Health Aspects in Polish Consumer Choices of Dairy Products

In general, dairy products are well regarded for their nutritional value. Consumer perception of dairy products is influenced by many interrelated factors but healthiness remains one of the key attributes and values for consumers. Furthermore, contemporary consumers increasingly seek out dairy products with additional health benefits and, therefore, it is essential to explore which attributes are important drivers of food choices and how producers can better respond to shifting consumer values and needs in each dairy product category. Therefore, the aims of the study were: (a) to identify consumer segments based on the importance they attached to selected attributes of dairy products, (b) to explore differences between the identified segments in their perceptions of health-related attributes of dairy products, (c) to determine if health-related aspects influenced consumers decisions to buy high-quality dairy products, and (d) to identify if consumers were open to novelties in dairy products. The data were collected within a CAPI (Computer Assisted Personal Interview) survey on a representative sample of 983 adult Polish consumers. The non-hierarchical K-means clustering method was used to identify four clusters of consumers, namely: Enthusiastic, Involved, Ultra-involved and Neutral. Enthusiastic consumers attach more importance to the influence of dairy products on immunity and are more willing to agree with the opinion that dairy products are a source of mineral nutrients as well as vitamins. Ultra-involved and Involved consumers pay less attention to some health aspects of dairy products compared to other clusters; however, the Ultra-involved are more quality-oriented than are the Involved. Neutral consumers are more open to accept changes on the dairy product market and are relatively more inclined to choose new dairy products. However, these consumers have scored lower on those aspects related to the healthiness of dairy products and, in order to target them effectively, it is essential to develop well-tailored communication strategies highlighting the health benefits of dairy products. These results relate to the Polish market and are important for the development of new dairy products and for targeting public nutrition as well as for directing marketing communication. The results may provide important insights for those who develop educational strategies and campaigns.

In vitro and in vivo antioxidant potential of milks, yoghurts, fermented milks and cheeses: a narrative review of evidence

The antioxidant potential (AP) is an important nutritional property of foods, as increased oxidative stress is involved in most diet-related chronic diseases. In dairy products, the protein fraction contains antioxidant activity, especially casein. Other antioxidants include: antioxidant enzymes; lactoferrin; conjugated linoleic acid; coenzyme Q10; vitamins C, E, A and D3; equol; uric acid; carotenoids; and mineral activators of antioxidant enzymes. The AP of dairy products has been extensively studied in vitro, with few studies in animals and human subjects. Available in vivo studies greatly differ in their design and objectives. Overall, on a 100 g fresh weight-basis, AP of dairy products is close to that of grain-based foods and vegetable or fruit juices. Among dairy products, cheeses present the highest AP due to their higher protein content. AP of milk increases during digestion by up to 2·5 times because of released antioxidant peptides. AP of casein is linked to specific amino acids, whereas β-lactoglobulin thiol groups play a major role in the AP of whey. Thermal treatments such as ultra-high temperature processing have no clear effect on the AP of milk. Raw fat-rich milks have higher AP than less fat-rich milk, because of lipophilic antioxidants. Probiotic yoghurts and fermented milks have higher AP than conventional yoghurt and milk because proteolysis by probiotics releases antioxidant peptides. Among the probiotics, Lactobacillus casei/acidophilus leads to the highest AP. The data are insufficient for cheese, but fermentation-based changes appear to make a positive impact on AP. In conclusion, AP might participate in the reported dairy product-protective effects against some chronic diseases.

Biomarkers of the metabolic syndrome: Influence of minerals, oligo- and trace elements

Influences of minerals, oligo- and trace elements on the concentration of biomarkers of the metabolic syndrome (MetS) are reviewed. Since food is a complex mixture of caloric compounds and essential non-caloric food components with multiple interactions and varying bioavailability, it is hard to separate or identify the effect of one single component in a total meal or diet. Moreover the diet contains various non-nutritive biologically active components, which may add some beneficial characteristics. Therefore, conclusions on the effect of components on various biomarkers of MetS are sometimes quite contradictory. Reasons therefore are mentioned. Literature data should be studied in detail to conclude whether a component is related to a reduction of MetS-related symptoms or whether its influence is merely affecting a biomarker.

Randomised controlled trial of effect of whole soy replacement diet on features of metabolic syndrome in postmenopausal women: study protocol

INTRODUCTION

Metabolic syndrome (MetS) is a public health problem in postmenopausal women. Whole soy foods are rich in unsaturated fats, high quality plant protein and various bioactive phytochemicals that may have a beneficial role in the management of MetS. The aim of the study is to examine the effect of whole soy replacement diet on the features of MetS among postmenopausal women.

METHODS AND ANALYSIS

This will be a 12-month, randomised, single-blind, parallel controlled trial among 208 postmenopausal women at risk of MetS or with early MetS. After 4 weeks' run-in, subjects will be randomly allocated to one of two intervention groups, whole soy replacement group or control group, each for 12 months. Subjects in the whole soy group will be required to include four servings of whole soy foods (containing 25 g soy protein) into their daily diet iso-calorically, replacing red or processed meat and high fat dairy products. Subjects in the control group will remain on a usual diet. The outcome measures will include metabolic parameters as well as a 10-year risk for ischaemic cardiovascular disease. We hypothesise that the whole soy substitution diet will notably improve features of MetS in postmenopausal women at risk of MetS or with early MetS. The study will have both theoretical and practical significance. If proven effective, the application of the whole soy replacement diet model will be a safe, practical and economical strategy for MetS prevention and treatment.

ETHICS AND DISSEMINATION

Ethics approval has been obtained from the Ethics Committee of the Chinese University of Hong Kong. The results will be disseminated via conference presentations and papers in academic peer reviewed journals. Data files will be deposited in an accessible repository.

TRIAL REGISTRATION NUMBER

NCT02610322.