Mediterranean diet and associations with the gut microbiota and pediatric-onset multiple sclerosis using trivariate analysis.

BACKGROUND: The interplay between diet and the gut microbiota in multiple sclerosis (MS) is poorly understood. We aimed to assess the interrelationship between diet, the gut microbiota, and MS. METHODS: We conducted a case-control study including 95 participants (44 pediatric-onset MS cases, 51 unaffected controls) enrolled from the Canadian Pediatric Demyelinating Disease Network study. All had completed a food frequency questionnaire ≤21-years of age, and 59 also provided a stool sample. RESULTS: Here we show that a 1-point increase in a Mediterranean diet score is associated with 37% reduced MS odds (95%CI: 10%-53%). Higher fiber and iron intakes are also associated with reduced MS odds. Diet, not MS, explains inter-individual gut microbiota variation. Several gut microbes abundances are associated with both the Mediterranean diet score and having MS, and these microbes are potential mediators of the protective associations of a healthier diet. CONCLUSIONS: Our findings suggest that the potential interaction between diet and the gut microbiota is relevant in MS.

Multiple sclerosis (MS) is a disease where the immune system attacks the protective covering of nerve cells in the brain. There may be a relationship between diet and bacteria within the gut and MS, however this is not well understood. We investigated how diet and gut bacteria are linked to MS in young people. We examined the diet and types of bacteria in stool samples from those with and without MS. We found that a diet richer in fiber and Mediterranean foods were less common in those with MS. This dietary pattern was linked to certain differences in the gut bacteria. These findings raise the possibility, but cannot prove, that what we eat may help prevent MS by influencing our gut bacteria. This research opens the door to further studies on how diet can impact MS through our gut bacteria.

A systematic review and meta-analysis of Dietary Inflammatory Index and the likelihood of multiple sclerosis/ demyelinating autoimmune disease.

Diet and inflammation may contribute to the development of multiple sclerosis (MS). The aim of this systematic review and meta-analysis was to assess the association between proinflammatory diet, as estimated by the Dietary Inflammatory Index (DII®), and the likelihood of developing MS or other demyelinating autoimmune diseases. A systematic search was performed of search engines and databases (PubMed, ISI Web of Sciences, Scopus, and Embase) to identify relevant studies before 10th June 2023. The search identified 182 potential studies, from which 39 full-text articles were screened for relevance. Five articles with case-control design (n = 4,322, intervention group: 1714; control group: 2608) met the study inclusion criteria. The exposure variable was DII, with studies using two distinct models: quartile-based comparisons of DII and assessment of continuous DII. The meta-analysis of high versus low quartiles of DII with four effect sizes showed a significant association with MS/demyelinating autoimmune disease likelihood, with an odds ratio (OR) of 3.26 (95% confidence interval (CI) 1.16, 9.10). The meta-analysis of four studies with DII fit as a continuous variable showed a 31% increased likelihood of MS per unit increment; which was not statistically significant at the nominal alpha equals 0.05 (OR 1.31; 95% CI 0.95, 1.81). In conclusion, this systematic review and meta-analysis provides evidence of a positive association between higher DII scores with the likelihood of developing MS, highlighting that diet-induced inflammation could play a role in MS or other demyelinating autoimmune diseases risk.

Vitamin K content of Australian-grown horticultural commodities.

Vitamin K is a multi-function vitamin that has emerging roles in bone, brain and vascular health. Vitamin K composition data remain limited globally and Australia has lacked nationally representative data for vitamin K1 (phylloquinone) in horticultural commodities. Primary samples (n = 927) of 90 Australian-grown fruit, vegetable and nut commodities were purchased in three Australian cities. We measured vitamin K1/phylloquinone in duplicate in 95 composite samples using liquid chromatography with electrospray ionisation-tandem mass spectrometry. The greatest mean concentrations of vitamin K1/phylloquinone were found in kale (565 µg/100 g), baby spinach (255 µg/100 g) and Brussels sprouts (195 µg/100 g). The data contribute to the global collection of vitamin K food composition data. They add to the evidence that vitamin K1/phylloquinone concentrations vary markedly between geographic regions, supporting development of region-specific datasets for national food composition databases that do not yet contain data for vitamin K. Such data are needed globally.

Associations between diet and disease progression and symptomatology in multiple sclerosis: A systematic review of observational studies.

BACKGROUND: Although many people with MS (pwMS) modify their diet after diagnosis, there is still no consensus on dietary recommendations for pwMS. A number of observational studies have explored associations of diet and MS progression, but no studies have systematically reviewed the evidence. This systematic review aimed to provide an objective synthesis of the evidence for associations between diet and MS progression, including symptoms and clinical outcomes from observational studies. METHODS: We performed a systematic review following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Electronic database searches were performed for studies completed up to 26 July 2023 using PubMed (Medline), Web of Science, CINAHL, Embase (Ovid), and Scopus, followed by citation and reference list checking. We included studies using diet quality scores or dietary indices. Studies assessing individual foods, nutrients, or dietary supplements were excluded. We used the Newcastle-Ottawa Scale to assess the risk of bias of included studies. RESULTS: Thirty-two studies met the inclusion criteria. Of these, 20 were cross-sectional and 12 prospective. The most frequent outcomes assessed were disability (n = 19), quality of life (n = 12), fatigue (n = 12), depression (n = 9), relapse (n = 8), anxiety (n = 3), and magnetic resonance imaging (MRI) outcomes (n = 4). Based on prospective studies, this review suggests that diet might be associated with quality of life and disability. There were also potential effects of higher diet quality scores on improved fatigue, disability, depression, anxiety, and MRI outcomes but more evidence is needed from prospective studies. CONCLUSIONS: Observational studies show some evidence for an association between diet and MS symptoms, particularly quality of life and disability. However, the impact of diet on other MS outcomes remains inconclusive. Ultimately, our findings suggest more evidence is needed from prospective studies and well-designed tailored intervention studies to confirm associations.

A collaborative approach to designing an online nutrition education program for people with multiple sclerosis.

PURPOSE: People with multiple sclerosis (pwMS) want disease-specific dietary advice to reduce the confusion around diet. This study used co-design principles to develop an online nutrition education program for pwMS. METHODS: Mixed-methods (multiphase sequential design). Phase 1: online survey (n = 114 pwMS) to explore preferred content and characteristics of a nutrition program and develop a draft program. Phase 2: feedback on the draft program from stakeholders (two meetings; n = 10 pwMS and multiple sclerosis (MS) health professionals) and pwMS (two workshops; n = 6) to produce a full program prototype. Phase 3: cognitive interviews (n = 8 pwMS plus 1 spouse) to explore acceptability and ease of comprehension of one module of the program, analysed using deductive content analysis. RESULTS: Preferred topics were included in the program, which were further developed with consumer feedback. Cognitive interviews produced four themes: (1) positive and targeted messaging to motivate behaviour change; (2) "not enough evidence" is not good enough; (3) expert advice builds in credibility; and (4) engaging and appropriate online design elements are crucial. CONCLUSIONS: Positive language appears to improve motivation to make healthy dietary changes and engagement with evidence-based nutrition resources. To ensure acceptability, health professionals can use co-design to engage consumers when developing resources for pwMS.IMPLICATIONS FOR REHABILITATIONCo-designed nutrition education programs can help people achieve high-quality diets in line with recommendations, but very few programs exist for people with multiple sclerosis (MS), and none were co-designedThe participatory research in this study was instrumental in ensuring that important information regarding program acceptability was identifiedCo-design can ensure that the language is appropriate for the target audience, and positive language appeared to improve motivation in people with MS to engage with the online nutrition education programWhere practical and feasible, health professionals should collaborate with MS consumers when developing resources, and use positive, empowering language.

Mapping the citation network on vitamin D research in Australia: a data-driven approach.

Vitamin D research can vary geographically, as vitamin D status is influenced by latitude, season, dietary intake, body mass index, ethnicity, and public health initiatives. Over the last two decades, research on vitamin D has increased in Australia, where the potential for sun exposure (a major source of vitamin D) is high. We aimed to identify key topics and gaps in vitamin D research in Australia using a data-driven approach. A literature search limited to Australian studies was conducted in the Web of Science Core Collection database. Citation network analysis was conducted to identify clusters and sub-clusters, depicted using word clouds. Topic analysis of each cluster and sub-cluster was conducted to identify topics and sub-topics, respectively. From 934 publications (over the period 1984-2022), nine topics and 60 sub-topics were identified. The nine topics were: vitamin D in vulnerable populations and its impact on child development; impact of sun exposure and ultraviolet-B radiation on various health conditions; vitamin D and falls and fractures in older adults; vitamin D and its association with health outcomes; vitamin D from sun exposure; testing of vitamin D status in Australia; vitamin D, calcium, and musculoskeletal health; vitamin D status and knee osteoarthritis; and vitamin D status and exercise performance in athletes. There were limited publications on vitamin D in Aboriginal and Torres Strait Islander peoples and dietary vitamin D. We have provided an overview of vitamin D research in Australia. The research trends and knowledge gaps identified can guide future research to better inform public health initiatives in Australia.

Effect of household cooking on the retention of vitamin D2 and 25-hydroxyvitamin D2 in pulse UV-irradiated, air-dried button mushrooms (Agaricus bisporus).

Vitamin D deficiency has widespread global prevalence. Fresh mushrooms exposed to ultraviolet (UV) radiation generate vitamin D2 which remains after drying. It is not clear if vitamin D2 is retained after rehydration and cooking of dried mushrooms. The aim of this study was to determine the true retention of both vitamin D2 and 25-hydroxyvitamin D2 (25(OH)D2) after cooking UV-irradiated, air-dried, then rehydrated button mushrooms (Agaricus bisporus). Mushrooms were exposed to pulsed UV radiation, then air-dried in a convection oven, followed by rehydration in warm water. Samples were cooked in three different ways: frying (5 min), baking (10 min, 200 °C) and boiling (20 min, 90 °C). Compared to rehydrated, uncooked controls, there was a high retention of D vitamers (≥95%) after cooking. Frying and baking resulted in significantly higher vitamin D2 retention compared to boiling (p < 0.0001). UV-irradiated, dried mushrooms are a valuable source of vitamin D2 after rehydration and cooking.

A pro-inflammatory diet in people with multiple sclerosis is associated with an increased rate of relapse and increased FLAIR lesion volume on MRI in early multiple sclerosis: A prospective cohort study.

BACKGROUND: A pro-inflammatory diet has been posited to induce chronic inflammation within the central nervous system (CNS), and multiple sclerosis (MS) is an inflammatory disease of the CNS. OBJECTIVE: We examined whether Dietary Inflammatory Index (DII®)) scores are associated with measures of MS progression and inflammatory activity. METHODS: A cohort with a first clinical diagnosis of CNS demyelination was followed annually (10 years, n = 223). At baseline, 5- and 10-year reviews, DII and energy-adjusted DII (E-DIITM) scores were calculated (food frequency questionnaire) and assessed as predictors of relapses, annualised change in disability (Expanded Disability Status Scale) and two magnetic resonance imaging measures; fluid-attenuated inversion recovery (FLAIR) lesion volume and black hole lesion volume. RESULTS: A more pro-inflammatory diet was associated with a higher relapse risk (highest vs. lowest E-DII quartile: hazard ratio = 2.24, 95% confidence interval (CI) = -1.16, 4.33, p = 0.02). When we limited analyses to those assessed on the same manufacturer of scanner and those with a first demyelinating event at study entry (to reduce error and disease heterogeneity), an association between E-DII score and FLAIR lesion volume was evident (ß = 0.38, 95% CI = 0.04, 0.72, p = 0.03). CONCLUSION: There is a longitudinal association between a higher DII and a worsening in relapse rate and periventricular FLAIR lesion volume in people with MS.

The Retention of Vitamin D2 and 25-Hydroxyvitamin D2 in Pulse UV-Irradiated Dried Button Mushrooms (Agaricus bisporus) after 12 Months of Storage.

Fresh mushrooms exposed to ultraviolet (UV) radiation prior to drying generate high concentrations of vitamin D2. The aim of this study was to determine the retention of D vitamers in mushrooms that were pulse UV irradiated, then air dried, and stored for up to 12 months. Fresh button mushrooms (A. bisporus) were exposed to pulsed UV radiation (dose 200 mJ/cm2, peak of 17.5 W/cm2), air dried and vacuum sealed before being stored in the dark at room temperature. After storage, samples were freeze dried and quantified for D vitamers using triple quadrupole mass spectrometry. After 3, 6 and 12 months of storage, there was 100% (11.0 ± 0.8 µg/g dry weight (DW), 93% (10.1 ± 0.6 µg/g DW) and 58% (5.5 ± 0.6 µg/g DW) retention of vitamin D2 and 88% (0.14 ± 0.01 µg/g DW), 71% (0.11 ± 0.01 µg/g DW) and 68% (0.1 ± 0.01 µg/g DW) retention of 25-hydroxyvitamin D2 (25(OH)D2), respectively. Compared to the irradiated dried mushrooms that were not stored, the D vitamer concentration was statistically significantly lower (p < 0.05) at 6 and 12 months for 25(OH)D2 and at 12 months for vitamin D2. Sufficient vitamin D2 (99 µg) remained after 12 months storage to provide at least 100% of daily dietary vitamin D requirements in a 20 g serving.

Vitamin D status in healthy populations worldwide: a systematic review protocol.

OBJECTIVE: The objective of this systematic review is to report on circulating concentrations of 25-hydroxyvitamin D (25[OH]D) and the prevalence of 25(OH)D concentrations below commonly used cut points for vitamin D deficiency, insufficiency, and sufficiency in healthy populations worldwide. INTRODUCTION: Vitamin D sufficiency is important for optimal bone health and has been identified as being protective against a range of adverse health outcomes. Poor vitamin D status is considered a global public health concern. This review will provide up-to-date data on 25(OH)D concentrations in healthy populations worldwide. INCLUSION CRITERIA: This review will consider data from publications that include measurements of circulating 25(OH)D concentrations in healthy people of all ages across all global geographical regions. METHODS: MEDLINE, Embase, Scopus, Web of Science, and Global Index Medicus will be searched for relevant studies published from March 1, 2011. Two reviewers will independently screen titles and abstracts using Research Screener, review relevant full-text articles for quality and eligibility, and extract data. Studies will, where possible, be pooled with statistical meta-analysis, while heterogeneity will be statistically tested. If relevant data are available, subgroup and sensitivity analyses will be conducted to investigate latitude, sex, age, season of blood collection, supplement use, 25(OH)D assay used (and whether it's certified to Reference Measurement Procedures developed under the Vitamin D Standardization Program), as well as study quality. REVIEW REGISTRATION: PROSPERO CRD42021242466.

Higher consumption of ultra-processed foods and increased likelihood of central nervous system demyelination in a case-control study of Australian adults.

BACKGROUND: Consumption of ultra-processed foods (UPFs) has been linked to risk of chronic diseases, with scant evidence in relation to multiple sclerosis (MS). METHODS: We tested associations between UPF consumption and likelihood of a first clinical diagnosis of central nervous system demyelination (FCD) (267 cases, 508 controls), a common precursor to MS. We used data from the 2003-2006 Ausimmune Study and logistic regression with full propensity score matching for age, sex, region of residence, education, smoking history, body mass index, physical activity, history of infectious mononucleosis, dietary misreporting, and total energy intake. RESULTS: Higher UPF consumption was statistically significantly associated with an increased likelihood of FCD (adjusted odds ratio = 1.08; 95% confidence interval = 1.0,1.15; p = 0.039), representing an 8% increase in likelihood of FCD per one energy-adjusted serving/day of UPFs. CONCLUSION: Higher intakes of UPF were associated with increased likelihood of FCD in this Australian cohort. Nutrition education and awareness of healthy eating patterns may benefit those at high risk of FCD.

Evidence of low vitamin D intakes in the Australian population points to a need for data-driven nutrition policy for improving population vitamin D status.

BACKGROUND: Nearly one in four Australian adults is vitamin D deficient (serum 25-hydroxyvitamin D concentrations [25(OH)D] < 50 nmol L-1 ) and current vitamin D intakes in the Australian population are unknown. Internationally, vitamin D intakes are commonly below recommendations, although estimates generally rely on food composition data that do not include 25(OH)D. We aimed to estimate usual vitamin D intakes in the Australian population. METHODS: Nationally representative food consumption data were collected for Australians aged ≥ 2 years (n = 12,153) as part of the cross-sectional 2011-2013 Australian Health Survey (AHS). New analytical vitamin D food composition data for vitamin D3 , 25(OH)D3 , vitamin D2 and 25(OH)D2 were mapped to foods and beverages that were commonly consumed by AHS participants. Usual vitamin D intakes (µg day-1 ) by sex and age group were estimated using the National Cancer Institute method. RESULTS: Assuming a 25(OH)D bioactivity factor of 1, mean daily intakes of vitamin D ranged between 1.84 and 3.25 µg day-1 . Compared to the estimated average requirement of 10 µg day-1 recommended by the Institute of Medicine, more than 95% of people had inadequate vitamin D intakes. We estimated that no participant exceeded the Institute of Medicine's Upper Level of Intake (63-100 µg day-1 , depending on age group). CONCLUSIONS: Usual vitamin D intakes in Australia are low. This evidence, paired with the high prevalence of vitamin D deficiency in Australia, suggests that data-driven nutrition policy is required to safely increase dietary intakes of vitamin D and improve vitamin D status at the population level.

Mapping the Literature on Diet and Multiple Sclerosis: A Data-Driven Approach.

Multiple sclerosis (MS) is a chronic neurological disease of the central nervous system that is currently incurable. Diet may influence the onset and progression of MS. A variety of literature reviews have been conducted in the field of diet and MS. However, conventional reviews mostly focus on specific topics rather than delivering a holistic view of the literature landscape. Using a data-driven approach, we aimed to provide an overview of the literature on diet and MS, revealing gaps in knowledge. We conducted citation network analysis to identify clusters of all available publications about diet and MS over the past 50 years. We also conducted topic analysis of each cluster and illustrated them in word clouds. Four main clusters were identified from 1626 publications: MS risk and symptom management; mouse models of MS; gluten sensitivity; and dysphagia. Citation network analysis revealed that in this emerging field, articles published after 1991 were more likely to be highly cited. Relatively few studies focused on MS disease progression compared to risk factors, and limited evidence was available for many foods and nutrients in relation to MS. Future studies could focus on filling these identified knowledge gaps.

Vitamin K content of cheese, yoghurt and meat products in Australia.

Vitamin K is vital for normal blood coagulation, and may influence bone, neurological and vascular health. Data on the vitamin K content of Australian foods are limited, preventing estimation of vitamin K intakes in the Australian population. We measured phylloquinone (PK) and menaquinone (MK) -4 to -10 in cheese, yoghurt and meat products (48 composite samples from 288 primary samples) by liquid chromatography with electrospray ionisation-tandem mass spectrometry. At least one K vitamer was found in every sample. The greatest mean (± standard deviation for foods sampled in multiple cities) concentrations of PK (4.9 µg/100 g), MK-4 (58 ± 9 µg/100 g) and MK-9 (8 ± 2 µg/100 g) were found in lamb liver, chicken leg meat and Cheddar cheese, respectively. Cheddar cheese (1.1 ± 0.3 µg/100 g) and cream cheese (1.0 µg/100 g) contained MK-5. MK-8 was found in Cheddar cheese only (4 ± 2 µg/100 g). As the K vitamer profile and concentrations appear to vary considerably by geographical location, Australia needs a vitamin K food composition dataset that is representative of foods consumed in Australia.

Total Dairy Consumption Is Not Associated With Likelihood of a First Clinical Diagnosis of Central Nervous System Demyelination.

Background: The evidence associating consumption of dairy products and risk of MS is contradictory and inconclusive. Objective: To test associations between dairy consumption and the likelihood of a first clinical diagnosis of central nervous system demyelination (FCD), a common precursor to MS. Methods: We used data from the 2003-2006 Ausimmune Study, a population-based Australian, multicentre, matched case-control study (272 cases, 519 controls). Total dairy consumption (servings/day) was calculated by summing consumption of milk, cheese and yogurt. Covariate-adjusted treatment effects using augmented inverse probability weighting was used to test for associations with FCD. We conducted sensitivity analyses in the subset of participants who had had a classic first demyelinating event (FDE), defined as a single, first episode of symptoms suggestive of CNS demyelination. Results: There were no statistically significant associations between total dairy consumption (per one serving/day) and FCD (adjusted OR 1.00; 95% CI 0.93, 1.07; p = 0.979). However, yogurt consumption (vs. no yogurt consumption) was associated with an 11% decreased likelihood of FDE (adjusted OR 0.89; 95% CI 0.89, 0.79; p = 0.046). Conclusion: While total dairy consumption was not associated with FCD in this Australian case-control study, yogurt consumption was associated with reduced likelihood of FDE.

Vitamin D Fortification of Milk Would Increase Vitamin D Intakes in the Australian Population, but a More Comprehensive Strategy Is Required.

Low vitamin D status (serum 25-hydroxyvitamin D (25(OH)D) concentration < 50 nmol/L) is prevalent in Australia, ranging between 15% and 32% in the adolescent and adult populations. Vitamin D intakes are also low across the population and were recently estimated at 1.8−3.2 µg/day on average, assuming equal bioactivity of the D vitamers. In combination, these findings strongly suggest that data-driven nutrition policy is needed to increase vitamin D intake and improve status in the Australian population. Food fortification is a potential strategy. We used up-to-date vitamin D food composition data for vitamin D3, 25(OH)D3, vitamin D2, and 25(OH)D2, and nationally representative food and supplement consumption data from the 2011−2013 Australian Health Survey, to model a fortification scenario of 0.8 µg/100 mL vitamin D for fluid dairy milks and alternatives. Under the modelled fortification scenario, the mean vitamin D intake increased by ~2 µg/day from baseline to 4.9 µg/day from food only (7.2 µg/day including supplements). Almost all individual intakes remained substantially below 10 µg/day, which is the Estimated Average Requirement in North America. In conclusion, this modelling showed that fortification of fluid milks/alternatives with vitamin D at the current permitted level would produce a meaningful increase in vitamin D intake, which could be of potential benefit to those with a low vitamin D status. However, this initial step would be insufficient to ensure that most of the population achieves the North American EAR for vitamin D intake. This approach could be included as an effective component of a more comprehensive strategy that includes vitamin D fortification of a range of foods.

Nutrition Education Programs for Adults with Neurological Diseases Are Lacking: A Scoping Review.

The nutrition recommendation for most common neurological diseases is to follow national dietary guidelines. This is to mitigate malnutrition, reduce the risk of diet-related diseases, and to help manage some common symptoms, including constipation. Nutrition education programs can support people in adhering to guidelines; hence the aim of this scoping review was to explore what programs have been implemented for adults with neurological diseases. We conducted this review according to a published a priori protocol. From 2555 articles screened, 13 were included (dementia n = 6; multiple sclerosis n = 4; stroke survivors n = 2; Parkinson's n = 1). There were no programs for epilepsy, Huntington's, and motor neurone disease. Program duration and number of sessions varied widely; however, weekly delivery was most common. Just over half were delivered by dietitians. Most did not report using a behavior change theory. Commonly used behavior change techniques were instruction on how to perform a behavior, credible source, and behavioral practice/rehearsal. Evidence of nutrition education programs for adults with neurological diseases is lacking. Of those that are published, many do not meet best practice principles for nutrition education regarding delivery, educator characteristics, and evaluation. More programs aligning with best practice principles are needed to assess characteristics that lead to behavior change.

Vitamin D composition of Australian game products.

The vitamin D content of many Australian game products is unknown. These foods are potential sources of vitamin D for remote-dwelling Aboriginal and Torres Strait Islander people, of whom 39% are vitamin D deficient (serum 25-hydroxyvitamin D3 (25(OH)D3) concentrations < 50 nmol/L). Vitamin D3, 25(OH)D3, vitamin D2 and 25(OH)D2 were measured by liquid chromatography-triple quadrupole mass spectrometry (LC-QQQ) in raw meat (camel, crocodile, emu, kangaroo), emu eggs and emu oil. Vitamin D3 (range, 0.5-14.5 µg/100 g) was found in all products except camel and kangaroo. All samples except kangaroo contained 25(OH)D3; some camel samples contained relatively high concentrations (range, 0.4-5.2 µg/100 g). Vitamin D2 was found in emu products and some kangaroo samples. We detected trace amounts of 25(OH)D2 in some camel and kangaroo samples. This study provides valuable insight into foods with a paucity of data on vitamin D content, showing that some are potentially useful sources of vitamin D.

Vitamin D metabolites and risk of first clinical diagnosis of central nervous system demyelination.

Low 25-hydroxyvitamin D (25(OH)D) concentration is a recognised risk factor for multiple sclerosis (MS). Associations with vitamin D metabolites and vitamin D binding globulin (VDBG) have not been widely studied. We assessed the association between vitamin D metabolites (25(OH)D2, 25(OH)D3, c3-epimer 25(OH)D3, 1,25-dihydroxyvitamin D3 (1,25(OH)2D3), and 24,25-dihydroxyvitamin D3 (24,25(OH)2D3)) measured by liquid chromatography-tandem mass spectrometry assays, VDBG measured using a polyclonal immunoassay, and calculated free and bioavailable 25(OH)D, free 1,25(OH)2D3, and the 24,25(OH)2D3: total 25(OH)D and total 1,25(OH)2D: total 25(OH)D ratios with risk of a first clinical diagnosis of CNS demyelination (FCD) in an Australian case-control study (n = 196 cases, n = 241 controls, matched on age, sex and study region). Higher 25(OH)D (adjusted odds ratio (AOR) = 0.94 (95 % confidence interval (CI) 0.85-1.03) per 10 nmol/L increment) and 24,25(OH)2D3 (AOR = 0.81 (95 %CI 0.65-1.00) per 1 nmol/L increment) concentrations were associated with reduced FCD risk. Our results were compatible with no association for the other vitamin D metabolites, ratios, or VDBG with FCD risk. Thus, using standardised assays, and a comprehensive range of vitamin D metabolites, we confirmed the association of higher 25(OH)D and reduced FCD risk, and describe a similar effect for 24,25(OH)2D3; free or bioavailable 25(OH)D were not associated with FCD risk.

A proinflammatory diet is associated with an increased likelihood of first clinical diagnosis of central nervous system demyelination in women.

BACKGROUND: While a number of studies have examined associations between dietary factors and risk of multiple sclerosis (MS), little is known about intakes of inflammation-modulating foods and nutrients and risk of MS. OBJECTIVES: To test associations between the Dietary Inflammatory Index (DII®) and risk of a first clinical diagnosis of central nervous system (CNS) demyelination (FCD) (267 cases, 507 controls) using data from the Ausimmune Study. METHODS: The 2003-2006 Ausimmune Study was a multicentre, matched, case-control study examining environmental risk factors for an FCD, a common precursor to MS. The DII is a well-recognised tool that categorises individuals' diets on a continuum from maximally anti-inflammatory to maximally pro-inflammatory. The DII score was calculated from dietary intake data collected using a food frequency questionnaire. Conditional logistic regression models were used to estimate the association between DII and FCD separately for men and women. RESULTS: In women, a higher DII score was associated with increased likelihood of FCD, with a 17% increase in likelihood of FCD per one-unit increase in DII score (adjusted odds ratio 1.17, 95% confidence interval 1.04-1.33). There was no association between DII and FCD in men (adjusted odds ratio 0.88, 95% confidence interval 0.73-1.07). CONCLUSIONS: These findings suggest that a pro-inflammatory diet is associated with an increased likelihood of FCD in women.