Vitamin D, a steroid hormone, is crucial for bone health and immune regulation, with growing evidence suggesting its involvement in thyroid disorders and other autoimmune conditions.
Vitamin D deficiency has been linked to an increased risk of depression and an exacerbation of depressive symptoms. Supplementation with Vitamin D may play a role in ameliorating certain depressive states, particularly in individuals with documented low levels.
Quick answer
What it is: Vitamin D deficiency has been linked to an increased risk of depression and an exacerbation of depressive symptoms.
The current evidence for Vitamin D's role in various conditions, particularly thyroid disorders, is supported by systematic reviews and human clinical trials. Reviews highlight its immunomodulatory effects and associations with autoimmune thyroid diseases. Clinical trials investigate its impact on thyroid function, antibody levels, and post-thyroidectomy complications. However, many studies are pilot or feasibility trials, indicating an early stage of research for some applications.
Last reviewed · Jun 2026
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Where this remedy is being discussed across the web and community.
A classical ketogenic diet typically provides ~70–80% of calories from fat, ~15–20% from protein, and only ~5–10% (often 20–50 g/day) from carbohydrates. The metabolic shift to ketosis lowers blood glucose and insulin, raises ketone bodies (beta-hydroxybutyrate, acetoacetate), and is being studied for neurological and metabolic conditions. Variants include the Modified Atkins Diet (MAD), Medium-Chain Triglyceride (MCT) ketogenic diet, and the Low Glycemic Index Treatment (LGIT).
Foods to emphasize
Fatty fish (salmon, sardines, mackerel)
Pasture-raised eggs
Avocado and olives
Extra-virgin olive oil, coconut oil, MCT oil
Grass-fed meat and poultry
Full-fat dairy (butter, ghee, hard cheeses)
Nuts and seeds (macadamia, pecan, walnut, chia, flax)
Low-carb leafy greens and cruciferous vegetables
Bone broth and electrolyte-rich foods
Foods to avoid
Sugar and sweetened beverages
Grains and starches (bread, pasta, rice, cereal)
Most fruit (except small portions of berries)
Legumes and beans
Starchy vegetables (potatoes, corn, peas)
Low-fat or sweetened dairy
Vegetable seed oils (soybean, corn, sunflower) in excess
Most processed and packaged foods
Key principles
Carbohydrate intake usually 20–50 g net carbs per day
Adequate protein (~1.2–1.7 g/kg) — not high-protein
Most calories from whole-food fats
Track electrolytes (sodium, potassium, magnesium) to prevent "keto flu"
Best initiated with clinician guidance if on medications for diabetes, blood pressure, or seizures
Typical duration: Often 3–6 months minimum to assess response; medically supervised protocols (e.g. for epilepsy) may be maintained for years.
Why it may help
Multiple Sclerosis (MS): Small trials and pilot studies suggest ketogenic and modified Atkins diets may reduce fatigue, improve quality of life, and lower inflammatory markers in relapsing MS. Used as an adjunct, not a replacement for disease-modifying therapy.
Type 2 Diabetes: Significant HbA1c and fasting glucose reductions in clinical trials. Monitor diabetes medications closely to avoid hypoglycemia.
Insulin Resistance: Most direct mechanism — lowers insulin demand by minimizing carbohydrate load.
Prediabetes: Rapid improvements in fasting glucose and HbA1c, often reversing prediabetes within months.
Ketogenic therapy is a medical intervention when used for seizure disorders or oncology — work with a clinician or registered dietitian experienced in ketogenic therapy. Not recommended in pregnancy, type 1 diabetes without supervision, pancreatitis, certain fatty-acid oxidation disorders, or active eating disorders.
Autoimmune Protocol (AIP)
A strict elimination version of paleo designed to calm autoimmune flares and identify food triggers through structured reintroduction.
The Autoimmune Protocol removes foods commonly implicated in immune activation and gut permeability — grains, legumes, dairy, eggs, nightshade vegetables, nuts, seeds, refined sugar, alcohol, and additives — for a 30–90 day elimination, followed by careful one-at-a-time reintroduction. It is most studied in Hashimoto's thyroiditis and inflammatory bowel disease.
Foods to emphasize
Quality meat, poultry, and seafood (especially wild-caught fatty fish)
Organ meats once or twice weekly
A wide variety of non-nightshade vegetables and leafy greens
Nuts and seeds (including seed-based spices like cumin, coriander)
Refined sugar and sweeteners
Alcohol
NSAIDs and food additives where possible
Key principles
Pair the elimination with sleep, stress management, and movement
Track symptoms in a journal during reintroductions
Reintroduce one food every 5–7 days and watch for symptom changes
Most people do NOT need to stay strict long-term — the goal is a personalized maintenance diet
Typical duration: 30–90 day strict elimination, then a structured staged reintroduction over weeks to months.
Why it may help
Leaky Gut: Removes the most common drivers of intestinal permeability (gluten, dairy, alcohol, NSAIDs, additives) and is foundational in many gut-repair protocols.
Multiple Sclerosis (MS): Used clinically as an aggressive anti-inflammatory elimination; evidence overlaps with Wahls-style and paleo trials showing reduced fatigue in MS.
AIP is restrictive and best done with a practitioner familiar with the protocol, especially when active autoimmune disease is involved or in pregnancy/lactation.
Anti-Inflammatory Diet
A whole-foods pattern designed to lower chronic, low-grade inflammation by emphasizing omega-3s, polyphenols, fiber, and minimizing ultra-processed foods, sugar, and seed oils.
The anti-inflammatory diet is not a single protocol but a synthesis of the patterns most consistently linked to lower inflammatory markers (CRP, IL-6, TNF-alpha) in human studies — Mediterranean-style eating, oily fish, abundant polyphenols, and low intake of ultra-processed foods, refined sugar, industrial seed oils, and excessive alcohol.
Foods to emphasize
Fatty fish 2–3x/week (salmon, sardines, mackerel, herring)
Extra-virgin olive oil
Berries, cherries, and other deeply colored fruit
Dark leafy greens and cruciferous vegetables
Turmeric, ginger, and culinary herbs
Green tea
Nuts (especially walnuts) and seeds (flax, chia)
Legumes and whole grains
Dark chocolate (≥70% cocoa) in moderation
Foods to avoid
Sugar-sweetened beverages and refined sugar
Ultra-processed snacks and ready meals
Industrial seed oils used at high heat (soybean, corn, sunflower, cottonseed)
Processed and cured meats
Refined flour products
Excess alcohol
Key principles
Cook with olive oil, finish with extra-virgin olive oil
Aim for 25–35 g of fiber per day from whole foods
Eat the rainbow — color diversity ~ polyphenol diversity
Limit added sugar to <25 g/day
Typical duration: A long-term eating pattern.
Why it may help
Multiple Sclerosis (MS): Lowering systemic inflammation is a plausible adjunct to disease-modifying therapy; aligns with Mediterranean-derived MS data.
Type 2 Diabetes: Reduces systemic inflammation that drives insulin resistance and beta-cell dysfunction.
Prediabetes: Lowers inflammatory markers linked to insulin resistance and metabolic progression.
Insulin Resistance: Reduces chronic low-grade inflammation that impairs insulin signaling.
Safe and flexible. Can be combined with Mediterranean, vegetarian, or plant-forward patterns.
Vegan Diet
A fully plant-based eating pattern that excludes all animal products — meat, fish, dairy, eggs, and honey.
A whole-food vegan diet emphasizes vegetables, fruit, legumes, whole grains, nuts, and seeds. It has been associated with improvements in body weight, blood lipids, and glycemic control, and is being studied for autoimmune and inflammatory conditions. It requires deliberate planning for vitamin B12, vitamin D, omega-3 (EPA/DHA), iodine, iron, zinc, and (sometimes) calcium.
Nuts and seeds (especially walnuts, chia, flax, hemp)
Fortified plant milks and nutritional yeast
Algae-based EPA/DHA supplement
Vitamin B12 supplement (non-negotiable)
Foods to avoid
Refined grains and sugar as the bulk of meals
Heavily processed vegan junk foods
Coconut and palm oils in excess
Key principles
B12 supplementation is required, not optional
Include a reliable iodine source (iodized salt or seaweed in moderation)
Get vitamin D from sun and/or a supplement
Combine grains and legumes across the day for complete protein
Choose calcium-fortified plant milk if not eating leafy greens daily
Typical duration: A long-term eating pattern.
Why it may help
Multiple Sclerosis (MS): Small trials (e.g. Swank-style and McDougall plant-based diets) suggest reductions in fatigue and improved quality of life in MS.
Vegan diets can be excellent or deficient — quality depends on planning. Pregnant, breastfeeding, and growing children on vegan diets should be followed by a registered dietitian.
Low-FODMAP Diet
A short-term elimination diet that restricts fermentable carbohydrates (FODMAPs) to identify food triggers in irritable bowel and other functional gut conditions.
FODMAPs (Fermentable Oligo-, Di-, Mono-saccharides And Polyols) are short-chain carbohydrates poorly absorbed in the small intestine. They draw water into the gut and are rapidly fermented by colonic bacteria, producing gas and bloating in sensitive people. The Monash University protocol uses a 2–6 week strict low-FODMAP elimination, followed by a structured reintroduction phase to identify personal triggers.
Foods to emphasize
Low-FODMAP vegetables: carrot, zucchini, spinach, bell pepper, cucumber, lettuce
The carnivore diet is the most aggressive elimination diet — it removes every plant food (and therefore every fiber, lectin, oxalate, gluten, and FODMAP source) to isolate animal-food tolerance. Proponents use it primarily as a short-term diagnostic elimination to surface food triggers in autoimmune, gut, and inflammatory conditions. Long-term safety data is limited and observational.
Foods to emphasize
Ruminant meat (beef, lamb, bison) — emphasized for nutrient density
Pasture-raised eggs
Fatty fish (salmon, sardines)
Organ meats (liver, kidney) once or twice weekly
Bone broth and bone marrow
Animal fats (tallow, butter, ghee)
Salt to taste
Optional: aged hard cheeses, heavy cream
Foods to avoid
All grains, legumes, and seeds
All vegetables and fruit
Nuts and plant oils
Sugar and sweeteners
Most processed foods
Alcohol
Key principles
Eat to satiety — no calorie counting
Salt food liberally to maintain electrolytes
Prioritize fattier cuts over lean meats
Reintroduce foods one at a time after the elimination window to identify triggers
Best tracked with a clinician given the radical nature of the change
Typical duration: Typically run as a 30–90 day elimination, then food reintroductions one at a time.
Why it may help
Leaky Gut: Removes all dietary fiber, FODMAPs, lectins, and plant antinutrients to give the gut lining a rest while reintroductions identify true triggers. Anecdotal evidence only.
Long-term effects on cardiovascular markers, bone health, and the gut microbiome are not well established. Avoid in chronic kidney disease, gout flares, or active eating disorders without medical supervision.
Linked nutrient deficiencies
Vitamin and mineral deficiencies commonly associated with the conditions this remedy may support.
Vitamin D
Fat-soluble vitamin
Hormone-like vitamin central to immune function, mood, bone, and thyroid health.
Low vitamin D status is one of the most widespread deficiencies globally and has been linked to autoimmune disease activity (Hashimoto's, MS), mood disorders, recurrent infections, and poor skin barrier function.
Common symptoms
Fatigue
Low mood
Frequent infections
Bone or muscle aches
Hair thinning
Food sources
Fatty fish (salmon, sardines)
Egg yolks
Cod liver oil
UV-exposed mushrooms
Fortified dairy
Lab markers to discuss
25-hydroxyvitamin D (target 40–60 ng/mL per most functional ranges)
Reference intake: Adults 600–800 IU/day RDA; functional medicine often targets 2,000–5,000 IU/day with monitoring.
Supplementation notes: Take with a fat-containing meal. Pair with vitamin K2 (MK-7) when supplementing higher doses long-term.
Why it matters here
Multiple Sclerosis (MS): Strong epidemiologic and clinical evidence linking low vitamin D to MS risk and relapse rates.
Low zinc is linked to recurrent infections, acne, slow wound healing, leaky gut, and impaired taste/smell. Often deficient in vegetarians and those with gut malabsorption.
Common symptoms
Frequent colds/infections
Acne or slow-healing skin
Loss of taste or smell
Hair loss
White spots on nails
Food sources
Oysters
Beef and lamb
Pumpkin seeds
Cashews
Lentils and chickpeas
Lab markers to discuss
Plasma or serum zinc
Zinc/copper ratio
Reference intake: 8–11 mg/day RDA.
Supplementation notes: Take away from iron and calcium. Long-term high-dose zinc depletes copper — pair with ~1 mg copper if dosing >30 mg/day.
Why it matters here
Leaky Gut: Zinc carnosine restores tight-junction integrity in clinical studies.
Sinus Infections: Supports epithelial repair and antimicrobial defense.
Viral Infections: Inhibits viral replication and supports immune cell function.
Hypothyroidism: Zinc supports TSH and thyroid hormone production.
Selenium reduces TPO antibodies in Hashimoto's and supports T4→T3 conversion. Deficiency is implicated in thyroid autoimmunity and viral susceptibility.
Deficiency is common in vegetarians/vegans, older adults, and those on PPIs or metformin. Strongly implicated in neurological symptoms (MS-like presentations), fatigue, anxiety, and cognitive decline.
Vitamin D receptors are present in various brain regions involved in mood regulation, including the hypothalamus and prefrontal cortex. It influences neurotransmitter synthesis (like serotonin), reduces inflammation, and regulates neurotrophic factors, all of which are implicated in the pathophysiology of depression.
How it works in more detail
Vitamin D is involved in immune regulation through effects on innate and adaptive immune responses mediated by vitamin D receptor (VDR) activation within immune cells. Experimental and translational studies support its role in promoting regulatory T-cell activity, modulating Th1/Th17 responses, and influencing autoantibody production. This immunomodulatory action is thought to contribute to its potential role in autoimmune diseases. Beyond immunity, vitamin D primarily regulates bone metabolism and calcium-phosphorus homeostasis.
How to use
Always consult a qualified clinician.
Editorial guidance
Suggested dosage
1,000-4,000 IU daily; higher doses, up to 10,000 IU, may be used under medical supervision to correct deficiency.
Research dosage range
Clinical trials have investigated various dosages, including routine low-dose calcium and vitamin D supplementation, and systematic vs. on-demand administration after thyroidectomy. Specific dosages for other conditions are not consistently reported in the provided studies.
Typical forms
capsule, tablet, liquid
Community tips
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Suggested dosage
1,000-4,000 IU daily; higher doses, up to 10,000 IU, may be used under medical supervision to correct deficiency.
General guidance — discuss specifics with a clinician.
Safety
Safety warnings
Vitamin D is generally safe at recommended doses. Excessive intake can lead to hypercalcemia, causing nausea, vomiting, weakness, and kidney problems. Monitoring blood levels, especially during high-dose or long-term therapy, is advisable.
General guidance — discuss specifics with a clinician.
Evidence ecosystem
Scientific literature, clinical guidance, government sources, ongoing research, traditional use, and lived experience — grouped by source type and quality.
Overall grade (B)
The current evidence for Vitamin D's role in various conditions, particularly thyroid disorders, is supported by systematic reviews and human clinical trials. Reviews highlight its immunomodulatory effects and associations with autoimmune thyroid diseases. Clinical trials investigate its impact on thyroid function, antibody levels, and post-thyroidectomy complications. However, many studies are pilot or feasibility trials, indicating an early stage of research for some applications.
Kawada K, Sato C, Ishida T, Nagao Y, Yamamoto T, Jobu K · Medicina (Kaunas, Lithuania) · 2025
Background and Objectives: Vitamin D supplementation is effective for allergic rhinitis; however, its usefulness is unclear. We conducted a systematic review and meta-analysis to examine the conditions in which vitamin D supplementation was effective in allergic rhinitis management. Materials and Methods: Randomized controlled trials of vitamin D supplementation used for patients with allergic rhinitis were searched for across different databases. We extracted scores on patients' symptoms and the medication types used as the baseline treatments and performed a meta-analysis to evaluate the effect of vitamin D supplementation on allergic rhinitis symptoms. Meta-regression and subgroup analyses were performed for the average age, proportion of female participants, concomitant medications, vitamin D administration durations, and baseline serum 25-hydroxyvitamin D levels. Results: In total, 2389 articles were screened, and 5 randomized controlled trials (RCTs) were included in the meta-ana
Tobias DK, Pradhan AD, Duran EK, Li C, Song Y, Buring JE · Nature communications · 2025 · n=220
Observational and experimental evidence suggests that vitamin D plays a role in type 2 diabetes (T2D). However, prior randomized supplementation trials are limited to high-risk patients with prediabetes. Here we aim to evaluate whether vitamin D supplementation reduces risk of T2D in a general population of older US adults. The study design is an ancillary analysis (VITAL-T2D) of The Vitamin D and Omega-3 Trial (VITAL), a completed randomized, double-blind, placebo-controlled 2 × 2 trial of daily vitamin D3 (cholecalciferol; 2000 IU/day) and omega-3 fatty acids (1 g/day) for the primary prevention of cancer and cardiovascular disease. We also conducted a systematic review and meta-analysis of vitamin D trial (≥1000 IU/d cholecalciferol) vs. placebo and T2D risk. We analyzed 22,220 adults with mean age 67.2 years (SD = 7.1) without T2D at enrollment (2011 to 2014), randomized to vitamin D3 or placebo. Mean body mass index (BMI) was 27.5
Dyer SM, Kwok WS, Suen J, Dawson R, Kneale D, Sutcliffe K · The Cochrane database of systematic reviews · 2025 · n=964
Falls in care facilities are common events, causing considerable morbidity and mortality for older people. This is an update of a review on interventions in care facilities and hospitals first published in 2010 and updated in 2012 and 2018 on interventions in care facilities and hospitals. This review has now been split into separate reviews for each setting.
To assess the benefits and harms of interventions designed to reduce the incidence of falls in older people in care facilities.
We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, CINAHL, and two trial registers to 10 May 2024 and used reference checking, citation searching, and contact with authors to identify eligible trials and records.
We included randomised controlled trials (RCTs) of any intervention for preventing falls in older people (aged over 65 years) in care facilities with any comparator. We excluded trials conducted in places of residence that do not provide residential heal
Meta-AnalysisPubMedVery High Quality
Systematic Reviews(37)
Structured reviews of the full body of evidence (incl. Cochrane).
Maunder A, Mardon AK, Rao V, Torkel S, Metri NJ, Liu J · Climacteric : the journal of the International Menopause Society · 2026
Menopausal hormone therapy is standard treatment, but some women use complementary therapies. This review examines complementary therapies for menopause to inform International Menopause Society (IMS) recommendations.
A systematic search of six databases (January 2022-December 2024) identified randomized controlled trials (RCTs) and systematic reviews on complementary therapies for menopause. Outcomes included menopausal, vasomotor, genitourinary, cardiometabolic, sleep symptoms, bone health and safety. The study quality and certainty of evidence were evaluated using Cochrane Risk of Bias (RoB2), A MeaSurement Tool to Assess Systematic Reviews (AMSTAR 2) and Grading of Recommendations, Assessment, Development, and Evaluation (GRADE).
From 3187 citations, 158 studies were included: one overview, 36 meta-analyses, seven systematic reviews and 114 RCTs. While promising evidence was found for acupuncture, Chinese herbal medicine (CHM), herbs, nutrients, mind-body/touch therapies for a va
The simultaneous manifestation of obesity, sarcopenia, and osteoporosis represents a condition known as osteosarcopenic adiposity (OSA). While evidence suggests that vitamin D status may influence the development of OSA, the results are still divergent, and no clear understanding of how vitamin D, through serum concentrations or supplementation, impacts OSA and its metabolic implications. Although several studies have explored the association between vitamin D and various diseases, research specifically focused on OSA is limited, making it unfeasible to conduct a systematic review. Thus, this integrative review aims to provide a comprehensive overview of the relationship between vitamin D (dietary intake and 25-hydroxyvitamin D serum levels) and OSA. The literature search was conducted in the PubMed/MEDLINE database. Overall, 16 studies were included (cross-sectional studies, n = 7; a scoping review, n = 1; and integrative reviews
Safari S, Shojaei-Zarghani S, Molani-Gol R, Rafraf M, Malekian M · Endocrinologia, diabetes y nutricion · 2025 · n=1127
Approximately 200 million people have been diagnosed with thyroid disease worldwide. Associations between thyroid disorders and nutritional factors have been established in former studies.
The Web of Science, PubMed, and Scopus databases and Google Scholar were searched without date restriction until June 2023 by using relevant keywords. All original articles written in English that studied the effects of vitamin D supplementation on TSH and thyroid hormones were eligible for the present review.
The present review included a total of 16 randomized controlled trials (RCTs) with 1127 participants (intervention group, 630; control group, 497). Based on the findings made, vitamin D supplementation had no significant effects on serum TSH levels in 9 cases (56.2%) reported in the trials. However, TSH levels were elevated in 4 studies (26.6%) and low in 3 (18.7%) cases after vitamin D administration. Four cases reported in 6 RCTs and 4 cases reported in 5 trials indicated no significant eff
Systematic ReviewPubMedVery High Quality
Clinical Guidelines(7)
Recommendations from medical societies (NICE, AHA, ADA, ACG, Endocrine Society…).
Demay MB, Pittas AG, Bikle DD, Diab DL, Kiely ME, Lazaretti-Castro M · The Journal of clinical endocrinology and metabolism · 2024
Numerous studies demonstrate associations between serum concentrations of 25-hydroxyvitamin D (25[OH]D) and a variety of common disorders, including musculoskeletal, metabolic, cardiovascular, malignant, autoimmune, and infectious diseases. Although a causal link between serum 25(OH)D concentrations and many disorders has not been clearly established, these associations have led to widespread supplementation with vitamin D and increased laboratory testing for 25(OH)D in the general population. The benefit-risk ratio of this increase in vitamin D use is not clear, and the optimal vitamin D intake and the role of testing for 25(OH)D for disease prevention remain uncertain.
To develop clinical guidelines for the use of vitamin D (cholecalciferol [vitamin D3] or ergocalciferol [vitamin D2]) to lower the risk of disease in individuals without established indications for vitamin D treatment or 25(OH)D testing.
A multidisciplinary panel of clinical experts, along with experts in guideline m
Clinical GuidelinePubMed (Practice Guideline)Very High Quality
Diet plays a critical role in human health, but especially for patients with inflammatory bowel disease (IBD). Guidance about diet for patients with IBD are often controversial and a source of uncertainty for many physicians and patients. The role of diet has been investigated as a risk factor for IBD etiopathogenesis and as a therapy for active disease. Dietary restrictions, along with the clinical complications of IBD, can result in malnutrition, an underrecognized condition among this patient population. The aim of this American Gastroenterological Association (AGA) Clinical Practice Update (CPU) is to provide best practice advice statements, primarily to clinical gastroenterologists, covering the topics of diet and nutritional therapies in the management of IBD, while emphasizing identification and treatment of malnutrition in these patients. We provide guidance for tailored dietary approaches during IBD remission, active disease, and intestinal failure. A healthy Mediterranean die
Clinical GuidelinePubMed (Practice Guideline)Very High Quality
Dent E, Morley JE, Cruz-Jentoft AJ, Woodhouse L, Rodríguez-Mañas L, Fried LP · The journal of nutrition, health & aging · 2019
The task force of the International Conference of Frailty and Sarcopenia Research (ICFSR) developed these clinical practice guidelines to overview the current evidence-base and to provide recommendations for the identification and management of frailty in older adults.
These recommendations were formed using the GRADE approach, which ranked the strength and certainty (quality) of the supporting evidence behind each recommendation. Where the evidence-base was limited or of low quality, Consensus Based Recommendations (CBRs) were formulated. The recommendations focus on the clinical and practical aspects of care for older people with frailty, and promote person-centred care. Recommendations for Screening and Assessment: The task force recommends that health practitioners case identify/screen all older adults for frailty using a validated instrument suitable for the specific setting or context (strong recommendation). Ideally, the screening instrument should exclude disability as part of
Clinical GuidelinePubMed (Practice Guideline)Very High Quality
Brustad N, Wang T, Chen L, Kaiser H, Gomes B, Klein A · Journal of the American Academy of Dermatology · 2026
Tobacco exposure has been shown to modulate the effect of vitamin D on the risk of atopic diseases. However, randomized clinical trials investigating the potential effect modification between tobacco exposure and vitamin D supplementation on atopic disease risk are lacking.
We sought to investigate the potential effect modification from maternal tobacco exposure on the effect of prenatal high-dose vitamin D supplementation on the risk of child atopic dermatitis, asthma, and allergic rhinitis.
A post hoc analysis in the double-blinded COPSAC2010 randomized clinical trial (NCT00856947) including 581 mother-child pairs randomized to 2800 IU/d (high-dose) versus 400 IU/d (standard-dose) from pregnancy week 24. Maternal blood metabolomic profiling was performed at inclusion, reflecting maternal tobacco exposure using a supervised sparse partial least squares model.
We found a significant effect modification from the maternal cotinine metabolome score (Pinteraction < .01) where high-do
Kodama S, Nakata M, Konishi N, Yoshino M, Fujisawa A, Naganuma M · Nutrients · 2026 · n=56
Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) can develop as post-vaccination syndrome (PVS) or Post-Acute Sequelae of SARS-CoV-2 infection (PASC). In our prior retrospective study, most patients with PVS who developed ME/CFS had vitamin D insufficiency or deficiency. We evaluated the efficacy of vitamin D replacement therapy guidance for ME/CFS symptom improvement in patients with vitamin D insufficiency or deficiency. Methods: This open-label randomized controlled trial enrolled 91 participants with ME/CFS as PVS or PASC and serum 25(OH) vitamin D < 30 ng/mL across five clinical sites. Participants were randomized 1:1 to intervention (active vitamin D preparation plus vitamin D replacement therapy guidance: 25 μg daily supplementation, dietary counseling, sun exposure, and exercise) or control (active vitamin D preparation alone) for 12 weeks. The primary endpoint was the change in ME/CFS symptom count from screening to Week 12. Results: Mean sympto
Thouvenot E, Laplaud D, Lebrun-Frenay C, Derache N, Le Page E, Maillart E · JAMA · 2025 · n=316
Vitamin D deficiency is a risk factor for multiple sclerosis (MS) and is associated with the risk of disease activity, but data on the benefits of supplementation are conflicting.
To evaluate the efficacy of high-dose cholecalciferol as monotherapy in reducing disease activity in patients with clinically isolated syndrome (CIS) typical for MS.
The D-Lay MS trial was a parallel, double-blind, randomized placebo-controlled clinical trial in 36 MS centers in France. Patients were enrolled from July 2013 to December 2020 (final follow-up on January 18, 2023). Untreated patients with CIS aged 18 to 55 years with CIS duration less than 90 days, serum vitamin D concentration less than 100 nmol/L, and diagnostic magnetic resonance imaging (MRI) meeting 2010 criteria for dissemination in space or 2 or more lesions and presence of oligoclonal bands were recruited.
Patients were randomized 1:1 to receive oral cholecalciferol 100 000 IU (n = 163) or placebo (n = 
Randomized TrialPubMedHigh Quality
Observational Studies(232)
Cohort, case-control, and cross-sectional human studies.
Qiu Y, Su X, Chen J, Jiang S, Tang X, He Y · ImmunoTargets and therapy · 2026
This review systematically summarizes breakthrough advances in vitiligo treatment from 2020 to 2025 to provide the latest evidence-based insights for clinical practice.
We searched ClinicalTrials.gov and PubMed for literature and clinical trials published within this period. Inclusion criteria encompassed randomized controlled trials (RCTs), Phase II and above clinical trial results, and fundamental research with clear clinical translational value.
Our analysis identified that JAK inhibitors achieved significant repigmentation by blocking the IFN-γ/JAK-STAT signaling pathway, while novel agents such as IL-15 inhibitors selectively eliminated pathogenic CD8⁺ T cells, suppressing immune-mediated damage at its source. The combination of 308 nm excimer laser with JAK inhibitors or platelet-rich plasma (PRP) increased repigmentation rates in acral lesions to 56.1%, and vitamin D adjunct therapy demonstrated synergistic effects. For stable disease, ReCell technology combined w
Bendotti G, Mele C, Costantini L, Ragni A, Leporati P, Biamonte E · Nutrients · 2026
Vitamin D is involved in immune regulation through effects on innate and adaptive immune responses mediated by vitamin D receptor activation within immune cells. Experimental and translational studies support its role in promoting regulatory T-cell activity, modulating Th1/Th17 responses, and influencing autoantibody production. At the population level, low serum 25-hydroxyvitamin D concentrations are consistently associated with an increased risk of autoimmune diseases, including autoimmune thyroid disorders such as Hashimoto's thyroiditis (HT) and Graves' disease (GD), suggesting a potential preventive association. In contrast, clinical evidence from interventional studies in patients with established disease is heterogeneous. Although vitamin D supplementation has been associated with reductions in thyroid autoantibody titers in some studies-particularly in patients with HT and baseline vitamin D deficiency-consistent effects on thyroid function, disease progression, or relapse prev
Cheng K, Hu Y, Li Y, Zhang Y, Wang J, Zhang C · Frontiers in immunology · 2026
Thyroid diseases are common endocrine disorders, with the incidence of thyroid cancer and autoimmune thyroid diseases rising worldwide. Vitamin D, a multifunctional steroid hormone, primarily regulates bone metabolism and calcium-phosphorus homeostasis. However, recent evidence increasingly supports the hypothesis that vitamin D plays a central role in the onset and progression of thyroid disorders, including both autoimmune and non-autoimmune conditions. In the present review, we summarize the correlation between vitamin D and thyroid disorders, elucidate the anticancer and immunoregulatory mechanisms of vitamin D in thyroid diseases, and explore its role in modulating gut microbiota. Additionally, we examine the applications in clinical settings of the use of vitamin D supplements in thyroid disorders, such as a preventive measure against cancer development and progression. Clarifying the mechanisms of vitamin D action in the development and progression of thyroid disease will suppor
Observational StudyPubMedLow Quality
Mechanistic Studies(1)
Lab and in-vitro work explaining how something might work.
Kowalik K, Waniewska-Łęczycka M, Sarnowska E, Rusetska N, Sierdziński J, Zagor M · Advances in clinical and experimental medicine : official organ Wroclaw Medical University · 2020 · n=52
The SWI/SNF (SWItch/sucrose non-fermentable) chromatin remodeling complex enables glucocorticoid receptor (GR) and vitamin D receptor (VDR) to function correctly and is engaged in inflammation response. The SWI/SNF may play an important role in chronic rhinosinusitis (CRS).
The aim of this study was to assess the following: 1) the gene and protein expression of the SWI/SNF complex subunits in sinonasal mucosa; 2) relation of SWI/SNF complex and VDR expression; and 3) correlation with clinical data.
The study population consisted of 52 subjects with CRS without nasal polyps, 55 with CRS with nasal polyps and 59 controls. The SWI/SNF protein expression level was analyzed in immunohistochemical (IHC) staining. Human nasal epithelial cells (HNECs) was stimulated using lipopolysaccharide (LPS), Staphylococcal enterotoxin B (SEB) and vitamin D3 (vitD3) in vitro. The transcript level of the SWI/SNF subunits was measured with polymerase chain reaction (PCR).
In the control group, the intens
Mechanistic StudyPubMedLow Quality
Animal Studies(2)
Preclinical animal research — not a substitute for human evidence.
Langerude L, McQuiston A, Atkinson C, Mulligan JK · International forum of allergy & rhinology · 2025
Smoking has been shown to be associated with circulating deficiencies in 25(OH)D3 and reduced sinonasal tissue levels of the active form of vitamin D, 1,25(OH)2D3. Given vitamin D's ability to reduce inflammation, we sought to examine if intranasal (IN) delivery of calcitriol [clinical analog of 1,25(OH)2D3] could reduce inflammation and improve disease severity in a murine model of chronic cigarette smoke-induced sinonasal inflammation (CS-SI).
Mice were exposed to CS 5 h/day, 5 days/week for 9 months, and then began IN calcitriol three times per week for 4 weeks. Micro-CT was used to assess disease severity. Sinonasal tissues were collected for RNA-seq analysis. Olfactory function was assessed using a T-maze odorant avoidance sniff behavior test. Nasal lavage fluid (NALF) was used for cytology and cytokines analysis.
Quantification of disease severity by micro-CT showed IN calcitriol reduced opacification by 18%, as compared to smoke cessation alone, in which only a 5% reduction wa
Trasciatti S, Piras F, Bonaretti S, Marini S, Nencioni S, Biasci E · The Journal of steroid biochemistry and molecular biology · 2022
Previous studies have shown a relationship between vitamin D and celiac disease (CD), however little evidence is available examining the direct effects of vitamin D on pathological features of this disease. In this study we evaluated the effect of oral administration of different doses of native vitamin D3 (cholecalciferol) in enteropathic mice. Female non-obese diabetic (NOD)/ShiLt.J mice were fed standard or gluten-free diet and administered gliadin (5 μg/kg) to induce a celiac pathology. Healthy control (gluten-free diet, without gliadin) and control for pathology (standard diet, with gliadin) were administered olive oil. All other experimental groups received gliadin and standard diet plus oral cholecalciferol (5, 10, 20, 50 and 130 μg/kg). Serum levels of 25(OH)D3, calcium and zonulin and expression of vitamin D receptor (VDR), CD3 and zonula occludens-1 (ZO-1) by immunohistochemistry as well as intestinal histological and histomorphometric analyses were unde
The NHS provides guidance on vitamin D, explaining what it does, how much is needed, and ways to get it, including advice on supplements. It offers practical health information for the public.
Government SourceNHS (National Health Service)High Quality
This fact sheet provides comprehensive information on vitamin D, including its functions, recommended intakes, deficiency, and potential health effects, including a section on thyroid health. It is a valuable resource for healthcare professionals.
This patient-focused resource from the Endocrine Society provides general information about Vitamin D, its importance, and common questions and answers.
Government SourceEndocrine SocietyHigh Quality
Clinical Trial Registries(189)
Registered ongoing or completed trials (ClinicalTrials.gov).
The purpose of this study is to determine if Vitamin D supplementation improves clinical and immunologic parameters in chronic rhinosinusitis with nasal polyps.
This study will be conducted to determine the effect of bioptron on PD through the assessment of serum progesterone level, and pain level measured by pressure algometry in addition to evaluation of the symptoms of PD and its effect on girl's quality of life through valid and reliable questionnaires which will be of valuable benefits in the women's health fields.
Clinical TrialClinicalTrials.govModerate Quality
Limitations: Many studies are clinical trials with relatively small sample sizes (e.g., n=17, n=30, n=50, n=82), which may limit the generalizability of their findings. Several studies are pilot or feasibility trials, suggesting preliminary research. The evidence for some specific applications, such as the role of vitamin D in preventing hypocalcemia after thyroidectomy, is still being investigated through various approaches and dosages, indicating a lack of standardized protocols.
Health Voice Perspectives
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Approved mentions from health educators, physicians, and researchers across podcasts, videos, and articles. Educational context only — does not influence the scientific evidence rating above.
Rhonda Patrick· PhD Biomedical Science, University of Tennessee
Dr. Steve Horvath discusses biological aging and the utility of epigenetic clocks like GrimAge and DunedinPACE in evaluating longevity interventions. He highlights that certain lifestyle factors, such as omega-3 intake, daily multivitamins, and sufficient vegetable consumption, are evidence-backed levers for positively influencing biological age. The focus is on removing factors that accelerate aging rather than dramatic reversal, emphasizing the importance of these interventions for healthspan and longevity.
"The strongest anti-aging strategy may be less about dramatic reversal and more about removing what accelerates aging in the first place. • Aging clocks are changing the way researchers evaluate longevity interventions. • GrimAge is a powerful mortality predictor. • Your epigenome remembers long-term stress. • Lifestyle changes can reverse GrimAge. • DunedinPACE tracks your aging speed. • Epigenetic clocks can potentially replace long-term mortality studies for testing longevity interventions. • A younger GrimAge doesn't necessarily mean more years of life. • Epigenetic clocks measure more than just inflammation. • No single intervention can stop aging. • Genetics are not your destiny regarding aging."
Rhonda Patrick· PhD Biomedical Science, University of Tennessee
Dr. Rhonda Patrick discusses the significant role of omega-3 fatty acids in promoting longevity and mitigating age-related health issues. She highlights their potential benefits for cardiovascular health, brain aging, and muscle maintenance, linking adequate intake to reduced risks of various chronic conditions. The presentation also addresses practical aspects of omega-3 supplementation, including dosage, forms, and dietary sources, emphasizing its importance as a longevity intervention.
"Low omega-3 intake may be a top preventable cause of death. • Higher omega-3 levels could extend lifespan. • Omega-3s may slow biological aging by resolving inflammation. • Higher omega-3 intake might protect the aging brain and slow hippocampal atrophy. • Omega-3s may lower Alzheimer's biomarkers. • Omega-3s can slow muscle loss during inactivity. • Omega-3s may suppress post-meal endotoxin release."
Drew Baird· Personal Trainer; Founder, NOVUM PCOS Coaching
Checks and corrects vitamin D status as a baseline step in his PCOS program.
"Before we talk fat loss or fertility with a PCOS client, we make sure vitamin D, iron, and B12 are sorted."
·6/4/2026
This page is educational. Statements use phrases like "may support" and "has been studied for"because no remedy here is approved to cure, treat, or reverse any condition. Discussion happens on the ailment pages — community statistics here are derived from those reports. Always consult a qualified clinician.
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