IMMUNE, SKIN & ANTIOXIDANT SUPPORT
30-day supply
Key Benefits
Powerful antioxidant supporting immune defense
Promotes collagen synthesis for skin and joints
Enhances iron absorption from plant sources
Supports cardiovascular health
Wellness Goals
Recommended Dose
1,000mg
Take one 1,000mg capsule daily with food. This buffered form (Calcium Ascorbate) is gentle on the stomach, unlike pure ascorbic acid. During illness or high stress, some people take an additional capsule. Vitamin C is water-soluble, so excess is excreted — but doses above 2,000mg/day may cause digestive discomfort.
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The Details
Vitamin C does so much more than fight colds. It's a cofactor in at least eight enzymatic reactions, including collagen synthesis (which is why sailors with scurvy lost their teeth — collagen literally holds your body together). It's one of the most potent water-soluble antioxidants, neutralizing free radicals in your blood and tissues before they can damage cells.
For immune support, vitamin C concentrates in immune cells at levels 10-100 times higher than in blood plasma. During an infection, immune cells rapidly consume their vitamin C stores as they mount a defense. Regular supplementation keeps those stores topped up so your immune system can respond with full force when needed. Meta-analyses show vitamin C supplementation reduces the duration of colds and may reduce severity.
Vitamin C also dramatically enhances the absorption of non-heme iron (the form found in plant foods and supplements), making it essential for vegetarians and anyone managing iron levels. It supports collagen production for skin elasticity and wound healing, and protects LDL cholesterol from oxidation — a key step in cardiovascular disease.
Research
Key studies supporting Vitamin C, from peer-reviewed journals.
Vitamin C intake and multiple health outcomes: an umbrella review of systematic reviews and meta-analyses — 2022
Vitamin C reduces the severity of common colds: a meta-analysis — 2023
Study titles are simplified for readability. Provided for informational purposes — not medical advice.
Transparency
Every batch is independently tested by ISO-17025 accredited labs for purity, potency, and contaminants.
Designed by healthcare professionals using evidence-based research and clinical expertise.
Manufactured in cGMP & UL certified, FDA-registered facilities with a flawless inspection record.
As with any natural health product, consult your healthcare practitioner. Store in a cool, dry place. Keep out of reach of children. Discontinue use immediately if you experience an adverse event.
What people say
Really good supplement brand. The daily pack format is so convenient and I've been 100% consistent because of it. The quiz was genuinely thorough. Knocked one star off because I'd love the option to add or remove individual supplements as I learn more about my body.
I've tried so many supplements and honestly nothing has worked like this. The quiz is actually thorough and the results show it. Energy is UP, recovery is UP, sleep is SO much better. Can't believe it took me this long to find this brand.
Three weeks in and I already feel the difference. My morning energy is COMPLETELY different. No more dragging myself out of bed. The personalization through the quiz is what makes it work — it's not just a generic multivitamin. Stack actually thought about what MY body needs.
I've been on a health optimization journey for about three years and have tried what feels like every supplement brand on the market. Most of them are either generic multivitamins dressed up in pretty packaging, or they're so specific that you need to be a nutritionist to understand what you're actually taking. Stack sits in a completely different category. The quiz is the first thing that impressed me. It asks genuinely intelligent questions — not just 'how old are you and what's your gender' but questions about your diet, your sleep patterns, your stress levels, your exercise frequency. It felt like a real consultation rather than a data collection exercise. The pack that arrived was clearly personalized to my answers. After six weeks, the improvements have been consistent and measurable: better sleep quality, more stable energy throughout the day, and noticeably faster recovery after my runs. My partner commented that I seemed more 'on' in the evenings rather than crashing after dinner. The daily pack format is brilliant for compliance — I've been 100% consistent because the habit is so frictionless. One pack, done, every morning. No bottles, no measuring, no forgetting half of them. Genuinely one of the best health investments I've made.
My focus at work has been sharper and I'm waking up without that groggy feeling I used to have every morning. Told two friends about Stack already. Customer support was also really helpful when I had a question about one of the ingredients.
honestly wasn't sure about it at first but three weeks in and i'm so glad i tried it. energy is way better, i'm sleeping properly for the first time in months. the quiz was really detailed which gave me confidence it was actually personalized. would 100% recommend.
Personalized for you
Take our 2-minute Health Assessment and let our AI build your personalized stack — every supplement chosen for your specific goals.
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