*Not all products in this category have an EFSA-approved health claim. Products with an EFSA claim are described as such in the text. For other products, they are grouped under this theme based on traditional use or product formula. For specific health questions, we recommend consulting a doctor or orthomolecular therapist.
Written by the Plenthera team (orthomolecularly trained). Scientifically reviewed in April 2026. Last updated: April 30, 2026.
The immune system works best when you support it — not stimulate it. In the Netherlands, vitamin D deficiency is widespread in winter (October-April), which is associated with more respiratory infections. Add vitamin C and zinc for the complete basic set. For those who want more: AHCC (standardized shiitake extract) and mushroom mix (reishi, chaga, maitake) add polysaccharides.
Which immune stack is right for you?
| Situation | Stack | Time of day |
|---|---|---|
| Winter prevention | D3 + C + zinc | Daily morning |
| Acute cold symptoms | High dose C + zinc + D3 | First 3-5 days |
| Premium immune stack | D3 + C + zinc + AHCC + mushroom mix | Daily |
| Long-term resistance | D3 + C + zinc + adaptogens | Ongoing |
| Travel / flying | C + zinc + probiotics | 1 week before + during |
What are immune & resistance?
The immune system consists of two main components: innate immunity (rapid, non-specific response) and acquired immunity (slow, specific response via antibodies and T-cells). Both require specific nutrients — especially vitamins D, C, zinc, A, and B vitamins.
Vitamin D is perhaps the most crucial immune component for the Dutch situation. In the winter period (October-April), the sun is too low for effective UV-B production — as a result, a large part of the population has suboptimal 25(OH)D blood values. Research shows a consistent association between low vitamin D status and increased susceptibility to respiratory infections.
The classic immune stack is D3 + C + zinc — all three EFSA-recognized for the immune system. Vitamin C supports white blood cells, zinc is a cofactor in T-cell function, and vitamin D modulates both. For the winter period, this is the basic approach.
For premium immune support, AHCC (a standardized shiitake extract with clinical data) and mushroom extracts (reishi, chaga, maitake) are interesting. These provide polysaccharides such as beta-glucans that modulate the innate immune system. Research is positive, but EFSA claims do not exist for these mushroom components.
Immune & Resistance and EFSA — what is scientifically recognized?
EFSA has not recognized an overarching immune claim. However, there are components with relevant recognized claims:
"Vitamin D contributes to the normal functioning of the immune system."
"Vitamin C contributes to the normal functioning of the immune system."
"Zinc contributes to the normal functioning of the immune system."
"Vitamin A contributes to the normal functioning of the immune system."
Thresholds apply to daily intake providing at least 15% RI.
The immune stack at Plenthera
Vitamin D3 25-75 µg (winter 75-100 µg)
EFSA-recognized for immune system. Higher dosage in winter.
Vitamin C 500-1000 mg
EFSA claim for immune. Liposomal or acerola/camu camu.
Zinc 15-25 mg
EFSA claim for immune. Bisglycinate or picolinate.
AHCC 1-3 g
Standardized shiitake extract.
Reishi + chaga + maitake combo
Broad mushroom mix.
Vitamin A (from beta-carotene) 800 µg RE
EFSA claim for immune system.
How to use immune & resistance?
Simple basic approach for immune:
- Measure Vitamin D3 status — especially in winter (October-April).
- Standard stack: D3 + C + zinc morning.
- For premium: add AHCC (1-3 g/day).
- For acute cold symptoms: temporarily increase C to 1000-2000 mg divided.
- Build up adaptogenic mushrooms (reishi/chaga/maitake) for long-term resistance.
- Combine with sleep hygiene and stress management.
- For chronic immune issues: medical diagnosis, not self-medication.
Myths and misconceptions about immune & resistance
Myth 1: "A pill solves immune issues."
Supplements are an addition to lifestyle, not a replacement.
Myth 2: "The more supplements, the better."
Stacking doesn't work — choose a targeted stack and give it time.
Myth 3: "Supplements work acutely for immune."
Cumulative effect, allow 4-8 weeks.
Myth 4: "All brands are equal."
Quality varies widely — choose premium for targeted effect.
Combining Immune & Resistance with other supplements
Supplements for the immune system and resistance work in a broader well-being cluster:
Frequently asked questions
Which supplements for the immune system?
D3, C, zinc — basic. Plus AHCC and mushrooms for premium.
Vitamin D for immune?
EFSA-recognized claim. Important during winter in NL.
Zinc for immune — how much?
15-25 mg per day. Bisglycinate or picolinate.
High dose vitamin C for colds?
1000-2000 mg divided for the first 3-5 days — meta-analyses show slight reduction in duration.
What is AHCC?
Standardized shiitake extract. Clinically studied for immune.
Mushrooms for immune?
Reishi, chaga, maitake contain beta-glucans. See our mushroom categories.
Echinacea for immune?
Classic herb — mixed scientific evidence. Not all brands equally effective.
When to take immune supplements?
Morning with a meal for optimal absorption of fat-soluble vitamins.
Immune supplements for children?
Adjusted dosages — child-specific formulas. Ask a therapist.
Long-term vs acute?
Long-term: D3 + zinc daily. Acute: high dose C for the first few days.
Sources
- EFSA Regulation (EU) 432/2012 — relevant component claims.
Disclaimer: This text is for informational purposes only and does not replace medical advice. Supplements are food supplements, not medicines. If in doubt or if taking medication, we recommend consulting a doctor or orthomolecular therapist first. For serious or persistent complaints: medical care remains the basis.