{"count":10,"index":{"built_at":"2026-07-28T00:15:01.445887+00:00","public_records":55311,"revision":"e46c6f23855cbb413d3bb47b"},"query":{"area":null,"kind":null,"lang":null,"limit":10,"match_mode":"all_terms","q":"Evidence check: Vitamin D Test in the context of fertility"},"results":[{"answer":"The question of a vitamin D test in the context of fertility is relevant but the evidence is nuanced. Vitamin D influences hormone regulation and oocyte maturation via its receptor (VDR), and some observational studies report lower vitamin D levels in women with fertility issues. However, randomized controlled trials demonstrating a causal benefit of routine vitamin D testing or supplementation on pregnancy rates are lacking. The provided knowledge contexts contain no specific data on vitamin D and fertility; they cover antibiotics, microbiome recovery, and isolated DNA markers (APOA2, FADS1, TCF7L2). Therefore, the evidence for a vitamin D test as a fertility marker is best classified as 'unclear'. Testing may be reasonable if deficiency is suspected (e.g., low sun exposure), but results should not be used as the sole basis for fertility decisions. Interpretation is limited by lack of standardized cutoffs and individual differences (e.g., VDR genetics). Safety note: excessive supplementation without proven deficiency can be toxic. Medical consultation is advised before testing and supplementing.","area":"gesundheit","canonical_id":"gesundheit:canonical-a01e2d1dd413ccc46c9979c7","id":"public-43326ada4418a9e2f938f370","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: Vitamin D Test in the context of fertility","score":17.66612663,"snippet":"The question of a vitamin D test in the context of fertility is relevant but the evidence is nuanced. Vitamin D influences hormone regulation and oocyte maturation via its receptor (VDR), and some observational studies report lower vitamin D levels in women with fertility issues. However, randomized controlled trials demonstrating a causal benefit of routine vitamin D testing or supplementation on pregnancy rates are lacking. The provided knowledge contexts contain no specific data on vitamin D and fertility; they cover antibiotics, microbiome recovery, and isolated DNA markers (APOA2, FADS1, TCF7L2). Therefore, the evidence for a vitamin D test as a fertility marker is best classified as 'u","sources":[],"title":"Evidence check: Vitamin D Test in the context of fertility","url":"https://tikki.wiki/wissen/gesundheit/frage/public-43326ada4418a9e2f938f370/evidence-check-vitamin-d-test-in-the-context-of-fertility/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"Vitamin D (25-OH) is increasingly discussed in the context of fertility. Observational studies suggest that low vitamin D levels are associated with reduced ovarian reserve, lower live birth rates after IVF, and poorer sperm quality in men. Mechanistically, vitamin D receptors are expressed in reproductive tissues and may influence hormone regulation and immune function. However, interventional trials show mixed results: some randomized controlled trials (RCTs) report improved pregnancy rates with supplementation, while others find no significant benefit. The evidence is therefore moderate – plausible biological pathways exist, but clinical utility remains uncertain. Correcting a deficiency is still advisable for overall health, but vitamin D testing alone is not a fertility solution. MyBody-X offers 25-OH measurement, but results should be integrated into a comprehensive fertility workup. Consumers should be cautious about overinterpreting single biomarkers.","area":"gesundheit","canonical_id":"gesundheit:canonical-bcd6e457c3bb50077fe7fca5","id":"public-2051c11ee6a23791f5da5782","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: Vitamin D 25-OH in the context of fertility","score":17.6376834,"snippet":"Vitamin D (25-OH) is increasingly discussed in the context of fertility. Observational studies suggest that low vitamin D levels are associated with reduced ovarian reserve, lower live birth rates after IVF, and poorer sperm quality in men. Mechanistically, vitamin D receptors are expressed in reproductive tissues and may influence hormone regulation and immune function. However, interventional trials show mixed results: some randomized controlled trials (RCTs) report improved pregnancy rates with supplementation, while others find no significant benefit. The evidence is therefore moderate – plausible biological pathways exist, but clinical utility remains uncertain. Correcting a deficiency ","sources":[],"title":"Evidence check: Vitamin D 25-OH in the context of fertility","url":"https://tikki.wiki/wissen/gesundheit/frage/public-2051c11ee6a23791f5da5782/evidence-check-vitamin-d-25-oh-in-the-context-of-fertility/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"The vitamin D receptor (VDR) is increasingly discussed in the context of fertility, especially in women with PCOS or endometriosis and in men with impaired semen quality. VDR polymorphisms (e.g., FokI, BsmI, TaqI) can affect vitamin D signaling, which may modulate steroid hormone production, oocyte maturation, and sperm function. However, the evidence is heterogeneous: some meta-analyses show moderate associations between certain VDR variants and fertility disorders, while other studies find no significant effects. Moreover, clinical relevance is often unclear because vitamin D levels and lifestyle factors strongly confound results. A DNA test for VDR alone does not provide reliable fertility prediction. MyBody-X tests may include these variants, but interpretation should always be within a comprehensive medical workup. Supplementation with vitamin D is reasonable if deficiency is confirmed, but genetic 'resistance' does not justify high-dose supplements. Caution against overblown claims: the evidence level is moderate, not strong.","area":"gesundheit","canonical_id":"gesundheit:canonical-2ebc0d5d865e3e0d91dececd","id":"public-2a91c36155d52cc35e8c6fa2","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: VDR in the context of fertility","score":17.46490599,"snippet":"The vitamin D receptor (VDR) is increasingly discussed in the context of fertility, especially in women with PCOS or endometriosis and in men with impaired semen quality. VDR polymorphisms (e.g., FokI, BsmI, TaqI) can affect vitamin D signaling, which may modulate steroid hormone production, oocyte maturation, and sperm function. However, the evidence is heterogeneous: some meta-analyses show moderate associations between certain VDR variants and fertility disorders, while other studies find no significant effects. Moreover, clinical relevance is often unclear because vitamin D levels and lifestyle factors strongly confound results. A DNA test for VDR alone does not provide reliable fertilit","sources":[],"title":"Evidence check: VDR in the context of fertility","url":"https://tikki.wiki/wissen/gesundheit/frage/public-2a91c36155d52cc35e8c6fa2/evidence-check-vdr-in-the-context-of-fertility/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"VKORC1 encodes vitamin K epoxide reductase complex subunit 1, primarily known for its role in warfarin metabolism. In the context of fertility, there is currently no strong scientific evidence directly linking VKORC1 variants to fertility outcomes. Some research explores vitamin K-dependent proteins in placental or endometrial function, but findings are preliminary and inconsistent. Most associations come from population genetics without clinical validation. If a consumer DNA test includes VKORC1 in a fertility panel, it is likely an exploratory or pharmacogenetic marker rather than a proven fertility predictor. The evidence level is unclear. Consumers should be cautious: such tests often overstate the relevance of single genes for complex traits like fertility. A healthcare professional should evaluate any genetic findings in the broader clinical context. At present, VKORC1 testing is not recommended for fertility assessment.","area":"gesundheit","canonical_id":"gesundheit:canonical-8ceb0d3270de9363ec310b6b","id":"public-2c1332596a66c355de1f83bc","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: VKORC1 in the context of fertility","score":17.39764427,"snippet":"VKORC1 encodes vitamin K epoxide reductase complex subunit 1, primarily known for its role in warfarin metabolism. In the context of fertility, there is currently no strong scientific evidence directly linking VKORC1 variants to fertility outcomes. Some research explores vitamin K-dependent proteins in placental or endometrial function, but findings are preliminary and inconsistent. Most associations come from population genetics without clinical validation. If a consumer DNA test includes VKORC1 in a fertility panel, it is likely an exploratory or pharmacogenetic marker rather than a proven fertility predictor. The evidence level is unclear. Consumers should be cautious: such tests often ov","sources":[],"title":"Evidence check: VKORC1 in the context of fertility","url":"https://tikki.wiki/wissen/gesundheit/frage/public-2c1332596a66c355de1f83bc/evidence-check-vkorc1-in-the-context-of-fertility/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"The evidence for vitamin D testing in the context of fertility is mixed and not strongly supported by high-quality clinical trials. While observational studies suggest associations between vitamin D status and reproductive outcomes (e.g., ovarian reserve, sperm quality, implantation), randomized controlled trials have not consistently demonstrated that testing or supplementation improves fertility. The VDR FokI polymorphism (rs2228570), often marketed as a 'vitamin D receptor variant,' has a small effect on receptor activity and is not considered actionable by current clinical guidelines. Additionally, inflammation can alter vitamin D levels, complicating interpretation. A vitamin D test may be reasonable if deficiency is suspected (e.g., limited sun exposure, dark skin), but routine testing for fertility is not evidence-based. MyBody-X and similar companies often overstate the significance of such tests. Consumers should interpret results cautiously and prioritize comprehensive fertility evaluation by a specialist.","area":"gesundheit","canonical_id":"gesundheit:canonical-a0e5b46634b6d0c36ca68e03","id":"public-011f62e27551853b0d3fa315","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: Vitamin D Test in the context of Fruchtbarkeit","score":17.35940123,"snippet":"The evidence for vitamin D testing in the context of fertility is mixed and not strongly supported by high-quality clinical trials. While observational studies suggest associations between vitamin D status and reproductive outcomes (e.g., ovarian reserve, sperm quality, implantation), randomized controlled trials have not consistently demonstrated that testing or supplementation improves fertility. The VDR FokI polymorphism (rs2228570), often marketed as a 'vitamin D receptor variant,' has a small effect on receptor activity and is not considered actionable by current clinical guidelines. Additionally, inflammation can alter vitamin D levels, complicating interpretation. A vitamin D test may","sources":[],"title":"Evidence check: Vitamin D Test in the context of Fruchtbarkeit","url":"https://tikki.wiki/wissen/gesundheit/frage/public-011f62e27551853b0d3fa315/evidence-check-vitamin-d-test-in-the-context-of-fruchtbarkeit/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"The provided context does not directly address the Nährstoffcheck (nutrient check) from MyBody-X or its relation to fertility. It is well established that nutrient deficiencies—such as vitamin D, iron, folate, and zinc—can impact fertility. However, the tests mentioned in the context (Vitamin-D Selbsttest, Women's Wellness Check) are lifestyle tools, not medical diagnostics. The Vitamin-D test gives only an approximate 25-OH-D3 value, and the Women's Wellness Check does not specifically measure iron or vitamin D according to the context. There is no evidence from the context that the Nährstoffcheck measures fertility-related markers. Therefore, while a link between nutrient status and fertility is biologically plausible, the specific relationship with this product is unsupported by the given information. For fertility assessment, clinical lab testing and medical consultation are recommended. The evidence is rated as unclear because marketing claims cannot be distinguished from scientific evidence.","area":"gesundheit","canonical_id":"gesundheit:canonical-86a06770d32a16c63ef4a34d","id":"public-d9c20c7cb6077163ee6b7182","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"How are Nährstoffcheck and fertility related?","score":17.2043854,"snippet":"The provided context does not directly address the Nährstoffcheck (nutrient check) from MyBody-X or its relation to fertility. It is well established that nutrient deficiencies—such as vitamin D, iron, folate, and zinc—can impact fertility. However, the tests mentioned in the context (Vitamin-D Selbsttest, Women's Wellness Check) are lifestyle tools, not medical diagnostics. The Vitamin-D test gives only an approximate 25-OH-D3 value, and the Women's Wellness Check does not specifically measure iron or vitamin D according to the context. There is no evidence from the context that the Nährstoffcheck measures fertility-related markers. Therefore, while a link between nutrient status and fertil","sources":[],"title":"How are Nährstoffcheck and fertility related?","url":"https://tikki.wiki/wissen/gesundheit/frage/public-d9c20c7cb6077163ee6b7182/how-are-naehrstoffcheck-and-fertility-related/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"The evidence for a direct link between the LCT genotype (lactase persistence/non-persistence) and fertility is weak and indirect. LCT determines adult lactose digestion capacity. Lactose intolerance may cause gastrointestinal discomfort, potentially impairing absorption of calcium and vitamin D—both relevant for reproductive health. Some observational studies suggest a possible association between dairy intake and ovulatory fertility, but they rarely genotype LCT. The data are inconsistent: adequate calcium may support oocyte quality, yet no randomized trials directly connect LCT variants to fertility outcomes. Effects are confounded by vitamin D status, gut microbiome, and inflammation. Consumer DNA tests that promote LCT in a fertility context often overstate the evidence. Conclusion: LCT is not an established fertility marker; however, personalized dietary advice for lactose intolerance can help prevent nutrient deficiencies.","area":"gesundheit","canonical_id":"gesundheit:canonical-85c05bd0d467eb8bc43b76cc","id":"public-47c9881e7d1b967a73e9c8fc","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: LCT in the context of Fruchtbarkeit","score":17.17506924,"snippet":"The evidence for a direct link between the LCT genotype (lactase persistence/non-persistence) and fertility is weak and indirect. LCT determines adult lactose digestion capacity. Lactose intolerance may cause gastrointestinal discomfort, potentially impairing absorption of calcium and vitamin D—both relevant for reproductive health. Some observational studies suggest a possible association between dairy intake and ovulatory fertility, but they rarely genotype LCT. The data are inconsistent: adequate calcium may support oocyte quality, yet no randomized trials directly connect LCT variants to fertility outcomes. Effects are confounded by vitamin D status, gut microbiome, and inflammation. Con","sources":[],"title":"Evidence check: LCT in the context of Fruchtbarkeit","url":"https://tikki.wiki/wissen/gesundheit/frage/public-47c9881e7d1b967a73e9c8fc/evidence-check-lct-in-the-context-of-fruchtbarkeit/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"The vitamin D receptor (VDR) mediates the genomic effects of vitamin D, which is known to influence fertility through roles in steroidogenesis, oocyte maturation, sperm quality, and implantation. Common VDR polymorphisms (e.g., FokI, BsmI, TaqI, ApaI) have been studied for associations with fertility outcomes, but the evidence remains largely mechanistic and observational. Effect sizes are small, and findings are inconsistent across populations. A consumer DNA test reporting VDR variants does not provide actionable fertility guidance on its own. The actual serum vitamin D level is a more clinically relevant marker, modifiable through sun exposure, diet, or supplementation. Caveat: Direct-to-consumer tests often overstate the significance of such genetic variants. Fertility issues should always be evaluated by a specialist, and no change in management should be based solely on a VDR genotype.","area":"gesundheit","canonical_id":"gesundheit:canonical-9660a7a85137a9791b70dbbe","id":"public-d30776a5775862068d635d6e","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: VDR in the context of Fruchtbarkeit","score":17.17121575,"snippet":"The vitamin D receptor (VDR) mediates the genomic effects of vitamin D, which is known to influence fertility through roles in steroidogenesis, oocyte maturation, sperm quality, and implantation. Common VDR polymorphisms (e.g., FokI, BsmI, TaqI, ApaI) have been studied for associations with fertility outcomes, but the evidence remains largely mechanistic and observational. Effect sizes are small, and findings are inconsistent across populations. A consumer DNA test reporting VDR variants does not provide actionable fertility guidance on its own. The actual serum vitamin D level is a more clinically relevant marker, modifiable through sun exposure, diet, or supplementation. Caveat: Direct-to-","sources":[],"title":"Evidence check: VDR in the context of Fruchtbarkeit","url":"https://tikki.wiki/wissen/gesundheit/frage/public-d30776a5775862068d635d6e/evidence-check-vdr-in-the-context-of-fruchtbarkeit/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"A fertility check in the context of sport is not a well-established medical standard. The evidence is weak: some genetic variants (e.g., in LEPR or GPX1) may theoretically influence hormone regulation or sperm quality, but effect sizes are small and study results are inconsistent. More relevant factors include training load, nutritional status (iron, zinc, vitamin D), stress, and sleep. Direct-to-consumer tests often provide probabilistic results without clinical validation. A proper fertility check should be medically supervised and typically includes hormone panels, semen analysis, and imaging – not just DNA markers. In sports, caution is warranted: overtraining can impair fertility, but a genetic test alone does not provide reliable insight.","area":"gesundheit","canonical_id":"gesundheit:canonical-ea990909925202746a365b36","id":"public-9b82aa3e07ae5830d97b7bad","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: Fertility Check in the context of Sport","score":17.15293181,"snippet":"A fertility check in the context of sport is not a well-established medical standard. The evidence is weak: some genetic variants (e.g., in LEPR or GPX1) may theoretically influence hormone regulation or sperm quality, but effect sizes are small and study results are inconsistent. More relevant factors include training load, nutritional status (iron, zinc, vitamin D), stress, and sleep. Direct-to-consumer tests often provide probabilistic results without clinical validation. A proper fertility check should be medically supervised and typically includes hormone panels, semen analysis, and imaging – not just DNA markers. In sports, caution is warranted: overtraining can impair fertility, but a","sources":[],"title":"Evidence check: Fertility Check in the context of Sport","url":"https://tikki.wiki/wissen/gesundheit/frage/public-9b82aa3e07ae5830d97b7bad/evidence-check-fertility-check-in-the-context-of-sport/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}},{"answer":"The role of vitamin D (25-OH) in fertility is increasingly discussed, but the evidence is mostly moderate. Observational studies link low vitamin D levels to reduced fertility in women (e.g., longer cycle length, lower oocyte quality) and men (lower sperm quality). Randomized controlled trials (RCTs) are fewer and show mixed results: some report improved live birth rates after supplementation, others no significant effect. The German Nutrition Society (DGE) recommends a 25-OH-D level of at least 50 nmol/l, but no specific fertility guidelines exist. Important: deficiency should be confirmed by blood test before supplementing, as long-term high doses (e.g., >100 µg/day) can be toxic. Individual genetics (e.g., VDR variants) may influence vitamin D metabolism, but the effect is small. Overall, maintaining adequate vitamin D is sensible but not a magic bullet. Evidence is based on human studies of moderate quality, not strong RCTs.","area":"gesundheit","canonical_id":"gesundheit:canonical-3474f7a600465f532b323f64","id":"public-d97cbf5d96ba4f13b2f32eb5","kind":"qa","language":"en","publication_status":"existing_native_answer_privacy_screened_sources_pending","question":"Evidence check: Vitamin D 25-OH in the context of Fruchtbarkeit","score":17.14656854,"snippet":"The role of vitamin D (25-OH) in fertility is increasingly discussed, but the evidence is mostly moderate. Observational studies link low vitamin D levels to reduced fertility in women (e.g., longer cycle length, lower oocyte quality) and men (lower sperm quality). Randomized controlled trials (RCTs) are fewer and show mixed results: some report improved live birth rates after supplementation, others no significant effect. The German Nutrition Society (DGE) recommends a 25-OH-D level of at least 50 nmol/l, but no specific fertility guidelines exist. Important: deficiency should be confirmed by blood test before supplementing, as long-term high doses (e.g., >100 µg/day) can be toxic. Individu","sources":[],"title":"Evidence check: Vitamin D 25-OH in the context of Fruchtbarkeit","url":"https://tikki.wiki/wissen/gesundheit/frage/public-d97cbf5d96ba4f13b2f32eb5/evidence-check-vitamin-d-25-oh-in-the-context-of-fruchtbarkeit/","verification":{"claim_support_verified":false,"human_reviewed":false,"quote_exact_match":false,"source_identity_verified":false,"tier":"existing_native_answer_privacy_screened_sources_pending"}}],"schema_version":"tikki.search-response.v1"}