Vitamin C
Citrus fruit, Bell peppers, Berries, Broccoli.
Back to TagsImmune claims are often overstated. Autoimmune disease, immunosuppression, transplant medicines, pregnancy, cancer treatment, and serious illness require clinician guidance.
Source mix: Official Reference, Traditional / Safety Reference, Government Health Agency. Vitamin C Fact Sheet for Health Professionals Vitamin A and Carotenoids Fact Sheet for Health Professionals Zinc Fact Sheet for Health Professionals Selenium Fact Sheet for Health Professionals Probiotics Fact Sheet for Consumers Herbs at a Glance Mixing Medications and Dietary Supplements Can Endanger Your Health
Tag
Immune Support
Immune-support references connect nutrients and bioactives involved in normal immune function, antioxidant biology, and strain- or product-specific immune research.
immuneimmunitycoldfluinfectionseasonalimmune system
Linked Items
7
May Support
5
Deficiency Signs
0
Cautions
2
Quick Compare
| Item | Type | Relationship | Evidence |
|---|---|---|---|
| Vitamin C | nutrient | May Support | Official nutrient-role framing from NIH ODS. Official Reference |
| Vitamin A | nutrient | May Support | Official nutrient-role framing from NIH ODS. Official Reference |
| Zinc | nutrient | May Support | Official nutrient-role framing from NIH ODS. Official Reference |
| Selenium | nutrient | May Support | Official nutrient-role framing from NIH ODS. Official Reference |
| Probiotics | bioactive | May Support | NIH ODS probiotic framing. Official Reference |
| Elderberry | bioactive | Caution / Limited Evidence | Botanical catalog safety framing from NCCIH/FDA source trails. Traditional / Safety Reference |
| Astragalus | bioactive | Caution / Limited Evidence | Botanical safety framing from NCCIH/FDA source trails. Traditional / Safety Reference |
Foods First
Vitamin A
Liver and some organ meats, Eggs and dairy foods, Orange and dark-green vegetables through provitamin A carotenoids.
Zinc
Oysters and meat, Dairy foods, Legumes and seeds.
Selenium
Brazil nuts, Seafood, Meat and eggs.
Probiotics
Yogurt with live cultures, kefir, kimchi, sauerkraut with live cultures, miso.
Elderberry
Cooked elderberries, elderberry syrups and extracts.
Astragalus
Astragalus membranaceus root.
Medication & Safety Cautions
Vitamin C
Vitamin C supports immune function and antioxidant physiology. | Very high intakes can cause gastrointestinal symptoms and may be unsuitable for some people prone to kidney stones.
Vitamin A
Vitamin A supports immune function and epithelial barriers. | The UL applies to preformed vitamin A, not beta-carotene from foods. | High preformed vitamin A intake can be especially concerning during pregnancy.
Zinc
Zinc is involved in immune function, DNA synthesis, and wound healing. | Long-term high-dose zinc can interfere with copper status.
Selenium
Selenium supports selenoproteins, including antioxidant enzymes and thyroid-related functions. | The margin between adequate intake and excessive intake is relatively narrow; respect the UL.
Probiotics
Some probiotic strains are studied for digestive and immune-related outcomes, but effects are strain-specific. | immunosuppression | serious illness | premature infants
Elderberry
Elderberry is traditionally used in seasonal immune products, but raw or improperly prepared plant parts can be unsafe and claim-level evidence still needs review. | product preparation | pregnancy/breastfeeding | autoimmune disease
Astragalus
Astragalus is used traditionally in immune and vitality formulas, but autoimmune disease, immunosuppressants, transplant medicines, and pregnancy need caution. | autoimmune disease | immunosuppression | transplant medications
Key Studies & Fixed References
These are the dated references used for this tag. Live research searches can change; these links explain the fixed wording shown on this page.
NIH Office of Dietary Supplements | Acquired 2026-07-24 | Official Reference
Vitamin C collagen synthesis, Wound healing context, Antioxidant role.
NIH Office of Dietary Supplements | Acquired 2026-07-23 | Official Reference
Preformed vitamin A, Provitamin A carotenoids, RAE conversion context.
NIH Office of Dietary Supplements | Acquired 2026-07-23 | Official Reference
Zinc supplement forms, Elemental zinc context, Zinc absorption and iron interaction.
NIH Office of Dietary Supplements | Acquired 2026-07-23 | Official Reference
Selenomethionine, Selenium yeast, Selenite.
NIH Office of Dietary Supplements | Acquired 2026-07-23 | Official Reference
Probiotic strain-specific framing, Fermented food examples.
National Center for Complementary and Integrative Health | Acquired 2026-07-23 | Traditional / Safety Reference
Botanical safety framing, Herb evidence summaries.
U.S. Food and Drug Administration | Acquired 2026-07-23 | Government Health Agency
Supplement-medication interaction warning language.
May Support
Vitamin C
nutrientOfficial Reference
Vitamin C supports immune function and antioxidant physiology.
Evidence note: Official nutrient-role framing from NIH ODS.
Sources: Vitamin C Fact Sheet for Health Professionals (2026-07-24)Official Reference
Vitamin A
nutrientOfficial Reference
Vitamin A supports immune function and epithelial barriers.
Evidence note: Official nutrient-role framing from NIH ODS.
Sources: Vitamin A and Carotenoids Fact Sheet for Health Professionals (2026-07-23)Official Reference
Zinc
nutrientOfficial Reference
Zinc is involved in immune function, DNA synthesis, and wound healing.
Evidence note: Official nutrient-role framing from NIH ODS.
Sources: Zinc Fact Sheet for Health Professionals (2026-07-23)Official Reference
Selenium
nutrientOfficial Reference
Selenium supports selenoproteins, including antioxidant enzymes and thyroid-related functions.
Evidence note: Official nutrient-role framing from NIH ODS.
Sources: Selenium Fact Sheet for Health Professionals (2026-07-23)Official Reference
Probiotics
bioactiveOfficial Reference
Some probiotic strains are studied for digestive and immune-related outcomes, but effects are strain-specific.
Evidence note: NIH ODS probiotic framing.
Sources: Probiotics Fact Sheet for Consumers (2026-07-23)Official Reference
Caution / Limited Evidence
Elderberry
bioactiveTraditional / Safety Reference
Elderberry is traditionally used in seasonal immune products, but raw or improperly prepared plant parts can be unsafe and claim-level evidence still needs review.
Evidence note: Botanical catalog safety framing from NCCIH/FDA source trails.
Sources: Herbs at a Glance (2026-07-23)Traditional / Safety Reference, Mixing Medications and Dietary Supplements Can Endanger Your Health (2026-07-23)Government Health Agency
Astragalus
bioactiveTraditional / Safety Reference
Astragalus is used traditionally in immune and vitality formulas, but autoimmune disease, immunosuppressants, transplant medicines, and pregnancy need caution.
Evidence note: Botanical safety framing from NCCIH/FDA source trails.
Sources: Herbs at a Glance (2026-07-23)Traditional / Safety Reference, Mixing Medications and Dietary Supplements Can Endanger Your Health (2026-07-23)Government Health Agency