Effects of dairy intake on hyperuricemia and gout

Opinion Piece: New Plant-Based Food Products Between Technology and Physiology

The rapid growth of product sectors for plant-based meat and dairy alternatives has raised significant scientific interest in their nutritional and ecological benefits. Here, it outlines the fractionation of plant-based raw materials and describes the technologies applied in the production of meat and dairy substitutes. Moreover, the study describes the effects of these new products on human nutrient supply and metabolic responses. Examples of meat-like products produced by extrusion technology and dairy alternatives are provided, addressing production challenges and the effects of processing on nutrient digestibility and bioavailability. In contrast to animal-based products, plant-based protein ingredients can contain many compounds produced by plants for defense or symbiotic interactions, such as lectins, phytates, and a wide range of secondary metabolites. The intake of these compounds as part of a plant-based diet can influence the digestion, bioaccessibility, and bioavailability of essential nutrients such as minerals and trace elements but also of amino acids. This is a critical factor, especially in regions with limited plant species for human consumption and inadequate technologies to eliminate these compounds. To fully understand these impacts and ensure that plant-based diets meet human nutritional needs, well-controlled human studies are needed.

A cross-sectional study of nutritional status in healthy, young, physically-active German omnivores, vegetarians and vegans reveals adequate vitamin B12 status in supplemented vegans

BACKGROUND/OBJECTIVE

Plant-based diets reduce the risk of cardiovascular disease but also increase the risk of certain micronutrient deficiencies, particularly, of vitamin B12 (B12). The extent to which the unsupervised use of oral nutrient supplements is sufficient to prevent these deficiencies is not well established. We analyzed nutrient intake, laboratory biomarkers, supplementation behavior, and B12 status adequacy amongst young, healthy, physically active omnivores, lacto-ovo-vegetarians and vegans from Germany.

METHODS

We recruited 115 participants (n = 40 omnivores; n = 37 lacto-ovo-vegetarians, and n = 38 vegans) with comparable age, sex, marital status, physical activity and educational levels through online advertisements and local newspapers in Freiburg, Germany.

RESULTS

Energy intake and macronutrient distribution were comparable across diets. Major differences included intake of fiber, cholesterol, and several vitamins. Vegans had the lowest intake of B12 from foods (0.43 (0.58) µg/d), compared to omnivores (2.14 (2.29) µg/d) and lacto-ovo-vegetarians (0.98 (1.34) µg/day). Multivariate analysis of 36 blood biomarkers revealed that three major classes of biomarkers contributed the most to the clustering of individuals by dietary group, namely, biomarkers of B12 status (B12, holoTC, Hcy), iron (iron, ferritin, transferrin) and lipid metabolism (vitamin A, HDL, LDL, total cholesterol, TAG). This suggests that nutrients that modify the metabolic pathways represented by these biomarkers have the most penetrating effect on health status across diets. Analysis of B12 status (including 4cB12) revealed adequacy in omnivores and vegans, and a poorer B12 status amongst lacto-ovo-vegetarians. Fewer lacto-ovo-vegetarians used B12 supplements compared to vegans (51% versus 90%).

CONCLUSIONS

Even amongst homogeneously healthy Germans, each diet manifested with measurable differences in dietary intakes and biomarkers of health. Plant-based diets, in particular the vegan diet, exhibited the most favorable patterns of lipid metabolism and glycemic control, but the lowest food intake of B12. Supplementation of healthy vegans with B12 (median 250 µg B12/day, over 2 years) secured an adequate B12 status that was comparable to that of healthy omnivores.Clinical Trial Registry: German Clinical Trial register number: DRKS00027425.

Milk kefir alters fecal microbiota impacting gut and brain health in mice

Kefir is a fermented beverage made of a symbiotic microbial community that stands out for health benefits. Although its microbial profile is still little explored, its effects on modulation of gut microbiota and production of short-chain fatty acids (SCFAs) seems to act by improving brain health. This work aimed to analyze the microbiota profile of milk kefir and its effect on metabolism, oxidative stress, and in the microbiota-gut-brain axis in a murine model. The experimental design was carried out using C57BL-6 mice (n = 20) subdivided into groups that received 0.1 mL water or 0.1 mL (10% w/v) kefir. The kefir proceeded to maturation for 48 h, and then it was orally administered, via gavage, to the animals for 4 weeks. Physicochemical, microbiological, antioxidant analyzes, and microbial profiling of milk kefir beverage were performed as well as growth parameters, food intake, serum markers, oxidative stress, antioxidant enzymes, SCFAs, and metabarcoding were analyzed in the mice. Milk kefir had 76.64 ± 0.42% of free radical scavenging and the microbiota composed primarily by the genus Comamonas. Moreover, kefir increased catalase and superoxide dismutase (colon), and SCFAs in feces (butyrate), and in the brain (butyrate and propionate). Kefir reduced triglycerides, uric acid, and affected the microbiome of animals increasing fecal butyrate-producing bacteria (Lachnospiraceae and Lachnoclostridium). Our results on the brain and fecal SCFAs and the antioxidant effect found were associated with the change in the gut microbiota caused by kefir, which indicates that kefir positively influences the gut-microbiota-brain axis and contributes to the preservation of gut and brain health. KEY POINTS: • Milk kefir modulates fecal microbiota and SCFA production in brain and colon. • Kefir treatment increases the abundance of SCFA-producing bacteria. • Milk kefir increases antioxidant enzymes and influences the metabolism of mice.

Correlating metal exposures and dietary habits with hyperuricemia in a large urban elderly cohort by artificial intelligence

Epidemiological studies using conventional statistical methods have reported an association between individual metal exposure and hyperuricemia (HUA). There is also evidence that diet may influence HUA development, although the available data are inconsistent. We therefore used an elastic net regression (ENR) model to screen the usefulness of various environmental and dietary factors as predictors of HUA in a large sample cohort. This study included 6217 subjects drawn from the Shenzhen Aging Related Disorder Cohort. We obtained information on the subjects' dietary habits via face-to-face interviews and used inductively coupled plasma mass spectrometry (ICP-MS) to measure the urinary concentrations of 24 metals to which elderly persons in large urban areas may be exposed. An elastic net regression (ENR) model was generated to screen the utility of the metals and dietary factors as predictors of HUA, and we demonstrated the superiority of the ENR model by comparing it to a traditional logistic regression model. The identified predictors were used to create a clinically usable nomogram for identifying patients at risk of developing HUA. The area under curve (AUC) value of the final model was 0.692 for the training set and 0.706 for the test set. Important predictors of HUA were Zn, As, V, and Fe as well as consumption of wheat, beans, and rice; the corresponding estimated odds ratios and 95% confidence intervals were 1.091 (0.932,1.251), 1.190 (1.093,1.286), 0.924 (0.793,1.055), 0.704 (0.626,0.781), 0.998 (0.996,1.001), 0.993 (0.989,0.998), and 1.001 (0.998,1.002), respectively. In contrast to previous studies, we found that both urinary metal concentrations and dietary habits are important for predicting HUA risk. Exposure to specific metals and consumption of specific foods were identified as important predictors of HUA, indicating that the incidence of this disease could be reduced by reducing exposure to these metals and promoting improved dietary habits.

[2022 Update of the Austrian Society for Rheumatology and Rehabilitation nutrition and lifestyle recommendations for patients with gout and hyperuricemia]

BACKGROUND

Gout is the most frequent inflammatory joint disease in the western world and has a proven genetic background. Additionally, lifestyle factors, such as increasing life expectation and standard of living, sufficient or excess nutrition and a growing prevalence of obesity in the population as well as e.g. alcohol consumption, contribute to the rising incidence of hyperuricemia and gout. Apart from an adequate medication, medical consultation on nutrition and lifestyle is an essential part of the management of gout patients, who have a high risk of internal comorbidities.

OBJECTIVE

In 2015 the Austrian Society for Rheumatology and Rehabilitation (ÖGR) working group for osteoarthritis and crystal arthropathies published nutrition and lifestyle recommendations for patients with gout and hyperuricemia. Since then, a multitude of studies have been published addressing this topic, which necessitated an update.

METHODS

First, the authors performed a hierarchical literature search to screen for the literature published since 2015. Considering references given in the first publication, the relevant literature was selected and the recommendations from 2015 were either kept as published, reformulated or recreated. Finally, the evidence level and the level of agreement for each recommendation were added by the authors.

RESULTS

Based on this process, 10 recommendations were generated instead of the initial 9. As in the original publication, a graphical presentation with symbols was constructed to complement the written text.

CONCLUSION

The ÖGR recommendations on nutrition and lifestyle for patients with gout and hyperuricemia were updated in accordance with the most recent relevant literature. These are supposed to serve as information and education material for patients and updated information for physicians.

2022 update of the Austrian Society of Rheumatology and Rehabilitation nutrition and lifestyle recommendations for patients with gout and hyperuricemia

Background

Gout is the most frequent inflammatory joint disease in the western world and has a proven genetic background. Additionally, lifestyle factors like increasing life span and wealth, sufficient to excess nutritional status and a growing prevalence of obesity in the population, as well as e.g. alcohol consumption contribute to the rising incidence of hyperuricemia and gout. Apart from an adequate medication, medical advice on nutrition and lifestyle is an essential part of the management of gout patients, being at high risk of internal comorbidities.

Objective

In 2015, the ÖGR (Österreichische Gesellschaft für Rheumatologie und Rehabilitation) working group for osteoarthritis and crystal arthropathies already published nutrition and lifestyle recommendations for patients with gout and hyperuricemia. Since then, a multitude of literature has been published addressing this topic, what required an update.

Methods

First, the authors performed a hierarchical literature search to screen the meanwhile published literature. Also considering references of the first publication, the relevant literature was selected, and the 2015 recommendations were either kept as published, reformulated or newly produced. Finally, the evidence level and the level of agreement with each recommendation were added.

Results

Following this process, ten recommendations were generated instead of the initial nine. Like in the original publication, a colored icon presentation was provided to complement the written text.

Conclusion

The Austrian nutrition and lifestyle recommendations for patients with gout and hyperuricemia were updated incorporating the most recent relevant literature, serving as education material for patients and updated information for physicians.

The Relationship between Modern Fad Diets and Kidney Stone Disease: A Systematic Review of Literature

OBJECTIVES

Kidney stone disease (KSD) has a strong association with diet metabolic syndrome. This review aims at exploring the lithogenic risk posed by the current most popular diets. Our approach was to search for the effect of each diet type on the major urinary risk factors, to try to draw conclusions regarding the association of a specific diet type and KSD.

METHODS

This systematic review searched for the available literature exploring the association between the existing popular fad diets and KSD. Articles in English, French and Spanish were included, without restriction of the search period with the final search done in August 2021.

RESULTS

Total number of studies and studies for each diet type was as follows: 22 articles for the low carbohydrate diet, 20 articles for high protein diets, 26 articles for vegetarian and vegan diets. There exists a substantial variability in different low carbohydrate and high protein diets, and considerable overlap between modern popular fad diets. High carbohydrate intake might increase urine uric acid, calcium and oxalate levels. High protein diets increase urine calcium and uric acid and lower urine pH and citrate. Consumption of fruits and vegetables increases the urinary volume and urinary citrate. In vegan diets, sufficient daily calcium intake is important to avoid possible secondary hyperoxaluria.

CONCLUSIONS

Few studies evaluated the direct relationship between modern fad diets and KSD. In general, the reduction of carbohydrate in the diet, and counterbalancing protein rich diets with sufficient intake of fruits and vegetables, seem to play a protective role against KSD formation. Maintaining sufficient calcium intake in vegan and vegetarian diets is important. Additional research is needed to directly evaluate the link between KSD and each diet type.

What You Eat Could Affect Your Sleep: Dietary Findings in Patients With Newly Diagnosed Obstructive Sleep Apnea

Rationale. We hypothesized that certain dietary components such as increased fat intake are associated with severity of obstructive sleep apnea (OSA). Methods. A total of 104 patients, diagnosed with OSA completed a validated dietary survey. The apnea-hypopnea index (AHI) was used to measure the severity of OSA. Subjects were divided using body mass index (BMI) into obese and overweight categories. Regression analysis was performed to predict severity of OSA from gender, BMI, age, % energy from fat, and the individual dietary components of the survey. Results. Overweight subjects who ate a diet high in fat (>35% of their total diet) had twice the severity of sleep apnea (AHI 18.2 ± 10.1 vs 36.6 ± 27.5; P = .001). There was a strong trend (P = .056) in OSA severity between subjects eating processed meats "often" (AHI 42.5 ± 30.7) versus those eating "rarely/never" (AHI 28.9 ± 22.7). Eating greater than 2 servings of dairy daily was associated with worsening severity of OSA (AHI 26.2 ± 15.6 vs 39.7 ± 31; P = .04]. Conclusions. Dietary components such as fat intake and processed meats were associated with increased risk of OSA severity. In addition, 2 servings of dairy foods were associated with a decreased severity of OSA at presentation.

Increased risk for hyperuricemia in adults sensitized to cow milk allergen

Several studies indicated the beneficial role of milk or dairy intake in protecting against gout or lowering rate levels. The elimination of milk or other dairy products due to cow milk allergies might increase the risk for gout and hyperuricemia. We investigated the potential risk of hyperuricemia in adults in the USAs according to the presence of milk allergen sensitization. We analyzed the data from the 2005-2006 National Health and Nutrition Examination. A total of 3893 adults with available data from specific IgE tests for milk allergen, serum uric acid levels, and no other missing information on their questionnaires were included in this study. Hyperuricemia was defined as serum uric acid levels >7.0 mg/dL. Overall, 151 (4.0 %) subjects were sensitive to milk allergen. The mean uric acid level in the sensitized subjects was higher than that in their non-sensitized counterparts. A significant difference in the rate of hyperuricemia between the two groups was found. Compared with subjects who were not sensitized to milk allergen (reference), subjects sensitized to milk allergen exhibited a significant increase in uric acid (β = 0.29; 95 % CI = 0.09-0.48) after adjusting for all potential covariates. In addition, the sensitized subjects, compared with the non-sensitized subjects, showed an increased risk of hyperuricemia (OR = 1.72; 95 % CI = 1.17-2.53). Adults who showed sensitivity to cow milk allergen were at a higher risk of hyperuricemia than those who were not sensitized, suggesting that restricted intake of milk or dairy products may be a possible risk factor for hyperuricemia.

Addition of a dairy fraction rich in milk fat globule membrane to a high-saturated fat meal reduces the postprandial insulinaemic and inflammatory response in overweight and obese adults

Meals high in SFA, particularly palmitate, are associated with postprandial inflammation and insulin resistance. Milk fat globule membrane (MFGM) has anti-inflammatory properties that may attenuate the negative effects of SFA-rich meals. Our objective was to examine the postprandial metabolic and inflammatory response to a high-fat meal composed of palm oil (PO) compared with PO with an added dairy fraction rich in MFGM (PO+MFGM) in overweight and obese men and women (n 36) in a randomised, double-blinded, cross-over trial. Participants consumed two isoenergetic high-fat meals composed of a smoothie enriched with PO with v. without a cream-derived complex milk lipid fraction ( dairy fraction rich in MFGM) separated by a washout of 1-2 weeks. Serum cytokines, adhesion molecules, cortisol and markers of inflammation were measured at fasting, and at 1, 3 and 6 h postprandially. Glucose, insulin and lipid profiles were analysed in plasma. Consumption of the PO + MFGM v. PO meal resulted in lower total cholesterol (P = 0·021), LDL-cholesterol (P = 0·046), soluble intracellular adhesion molecule (P = 0·005) and insulin (P = 0·005) incremental AUC, and increased IL-10 (P = 0·013). Individuals with high baseline C-reactive protein (CRP) concentrations (≥3 mg/l, n 17) had higher (P = 0·030) insulin at 1 h after the PO meal than individuals with CRP concentrations <3 mg/l (n 19). The addition of MFGM attenuated this difference between CRP groups. The addition of a dairy fraction rich in MFGM attenuated the negative effects of a high-SFA meal by reducing postprandial cholesterol, inflammatory markers and insulin response in overweight and obese individuals, particularly in those with elevated CRP.

Comparison of the effect of high fruit and soybean products diet and standard diet interventions on serum uric acid in asymptomatic hyperuricemia adults: an open randomized controlled trial

The aim of this study was to compare the effect of high fruit and soybean products diet and standard diet interventions on serum uric acid (SUA) in asymptomatic hyperuricemia adults. A total of 187 Chinese adults (20-59 years old) with asymptomatic hyperuricemia participated in this randomized trial and were assigned to receive the standard diet recommended by guideline (group 1) and high fruit and soybean products diet (group 2) for 3 months. The outcome of SUA was assessed before and at the end of the intervention period. After 3 months, the SUA in group 1 and group 2 was significant reduced, whereas the SUA was not significantly changed in-between groups. These data suggest that over a 3-month period, although the high fruit and soybean products diet and standard diet interventions yield no different effects on SUA, the high fruit and soybean products dietary intervention could be an effective alternative to a standard diet for achieving clinically important reductions in SUA for asymptomatic hyperuricemia patients.

An old disease with new insights: Update on diagnosis and treatment of gout

Gout is an acute and chronic inflammatory disorder associated with high morbidity and impaired quality of life. There has been a substantial increase in the prevalence and incidence of gout in recent years. Novel diagnostic and therapeutic options have provided new insights into the pathogenesis and management of hyperuricemia and gout in the last decade. This clinical review aims to summarize the diagnostic process and management of acute and chronic gout.

Bovine Peptic Casein Hydrolysate Ameliorates Cardiovascular Risk Factors in a Model of ApoE-deficient Mice but not Overweight, Mildly Hypercholesterolaemic Men

Associations have been shown between consumption of bovine dairy and decreased prevalence of metabolic related disorders. Milk peptides may promote both angiotensin-I- converting enzyme (ACE) inhibition for blood pressure (BP) lowering and insulin action for better glycaemic control. Less is known of other metabolic parameters. The aim of this study was to investigate effects of dairy peptic casein hydrolysate (CH) on markers of cardiovascular disease (CVD) risk in (1) an apolipoproteinE (ApoE) - deficient mouse model of high-fat fed hypercholesterolaem- ia, and, (2) a clinical study of moderate overweight and hypercholesterolaemia. In Trial 1, ApoE-deficient mice were supplemented with high dose CH (~1g/kg body weight) in a randomised, 9-wk, parallel design intervention, and blood and tissue samples harvested. In Trial 2, 24 mildly hypercholesterolaemic men were supplemented with lower dose CH (~0.1g/kg body weight, 10g/day, 3-wks) and matched whey protein control (WP, 10g/day, 3-wks) in a randomised, 9-wk, cross-over design intervention. Diets were separated by a 3-wk washout. Fasting blood and urine samples were collected, and blood pressure (BP) measured weekly. Clinical trial registration number, ACTRN 12611001013954. In ApoE-deficient mice, administration of CH significantly inhibited circulating total cholesterol concentrations by 37% (TC, P<0.01) and decreased aorta atherosclerotic lesion score by 25% (P<0.01). In the clinical study there were no significant differential effects of CH supplementation on CV markers, including serum lipids (TC, LDL-C, HDL-C, triglyceride), glucose and BP. Whilst high dose bovine peptic CH attenuated CVD risk in a murine ApoE deficient model of aggressive hypercholesterolaemia, no evidence of amelioration of risk by supplementation with a lower dose of CH in an overweight population of mildly hypercholesterolaemic men was found.

High serum ferritin levels increase the risk of hyperuricemia: a cross-sectional and longitudinal study

BACKGROUND/AIMS

To examine the cross-sectional and longitudinal associations of serum ferritin levels with hyperuricemia.

METHODS

A cross-sectional and subsequently prospective study was performed among the employees of Zhenhai Refining and Chemical Company, Ningbo, China. In a cross-sectional study, the association between serum ferritin levels and the prevalence of hyperuricemia was analyzed. Subjects who were free of hyperuricemia at baseline were followed up annually to explore the prospective association between serum ferritin levels and hyperuricemia incidence.

RESULTS

Of the 10,074 subjects enrolled at baseline, 1,731 (17.18%) fulfilled the diagnostic criteria of hyperuricemia. Subjects with hyperuricemia presented significantly higher serum ferritin levels, and the levels were positively correlated with the prevalence of hyperuricemia. During a total of 22,367 person-years of follow-up, 502 subjects developed hyperuricemia. The overall incidence of hyperuricemia for 1,000 person-years of follow-up was 22.4, ranging from 17.6 in subjects with baseline serum ferritin levels in the first quintile to 19.2, 21.7, 23.9, and 30.7 in subjects in quintiles 2, 3, 4, and 5, respectively (p for trend < 0.001). Cox regression analyses showed that serum ferritin levels were positively associated with the risk of incident hyperuricemia.

CONCLUSIONS

Our cross-sectional and longitudinal results indicate that high serum ferritin levels increase the risk of hyperuricemia.

Serum uric acid concentrations in meat eaters, fish eaters, vegetarians and vegans: a cross-sectional analysis in the EPIC-Oxford cohort

INTRODUCTION

Circulating concentrations of uric acid may be affected by dietary components such as meat, fish and dairy products, but only a few studies have compared uric acid concentrations among individuals who exclude some or all of these foods from their diet. The aim of this study was to investigate differences in serum uric acid concentrations between meat eaters, fish eaters, vegetarians and vegans.

SUBJECTS AND METHODS

A sample of 670 men and 1,023 women (424 meat eaters, 425 fish eaters, 422 vegetarians and 422 vegans, matched on age and sex) from the European Prospective Investigation into Cancer and Nutrition Oxford cohort were included in this cross-sectional analysis. Diet was assessed using a semi-quantitative food frequency questionnaire and serum concentrations of uric acid were measured. Mean concentrations of uric acid by diet group were calculated after adjusting for age, body mass index, calcium and alcohol intake.

RESULTS

In both men and women, serum uric acid concentrations differed significantly by diet group (p<0.0001 and p = 0.01, respectively). The differences between diet groups were most pronounced in men; vegans had the highest concentration (340, 95% confidence interval 329-351 µmol/l), followed by meat eaters (315, 306-324 µmol/l), fish eaters (309, 300-318 µmol/l) and vegetarians (303, 294-312 µmol/l). In women, serum uric acid concentrations were slightly higher in vegans (241, 234-247 µmol/l) than in meat eaters (237, 231-242 µmol/l) and lower in vegetarians (230, 224-236 µmol/l) and fish eaters (227, 221-233 µmol/l).

CONCLUSION

Individuals consuming a vegan diet had the highest serum concentrations of uric acid compared to meat eaters, fish eaters and vegetarians, especially in men. Vegetarians and individuals who eat fish but not meat had the lowest concentrations of serum uric acid.