Everything you need to know about Full-immunity:
the complete guide

What is Full-immunity?

It is a capsule designed for the whole cold season, not for a single week. The daily dose is two capsules, and they contain four nutrients with a recognised role in the functioning of the immune system, plus three ingredients you rarely find in an off-the-shelf formula.

• Four nutrients with a clear role. Vitamin C, zinc, selenium and vitamin D contribute to the normal function of the immune system.
• Cell protection. Vitamin C, zinc and selenium contribute to the protection of cells from oxidative stress.
• Less tiredness. Vitamin C contributes to the reduction of tiredness and fatigue.
• Three extra ingredients. 800 mg bovine colostrum, 100 mg quercetin from Sophora japonica buds and 100 mg Lion's Mane fruiting body extract.

How to take it

Two capsules, with a glass of water, during a meal. Once a day. The meal is not decoration: vitamin D needs the fat in your food to be absorbed, so the same capsule taken on an empty stomach does not give you the same thing. A bottle holds 60 capsules, which is exactly 30 days.

What makes Full-immunity different?

• Seven actives, seven doses on the label. No proprietary blends and no quantities hidden behind a formula name.
• 4,000 IU of vitamin D3. Most immunity capsules stop at 1,000 or 2,000 IU. The form is cholecalciferol from lanolin, the same one your skin produces in the sun.
• Vitamin C as calcium ascorbate. A buffered form, not plain ascorbic acid. 300 mg per dose, which is 375% of the nutrient reference value.
• Zinc from sulphate, selenium from yeast. Not zinc oxide, and the selenium comes from Saccharomyces cerevisiae grown on a selenium-enriched medium. The elemental amounts are declared separately on the label.
• Lion's Mane from the fruiting body. An extract from the mushroom itself, not from mycelium grown on grain, and the beta-glucan content is stated on the label.
• No fillers. No added sugar, no colourings, no flavourings. Made in the European Union under good manufacturing practice, with a certificate of analysis for every batch.

What a normally functioning immune system actually means

The most widespread idea about immunity is also the most mistaken one: that there is a volume knob somewhere. That the system can be turned up when you need it and left alone the rest of the time.

That is not how it is built. The immune system is a network of cells, proteins and barriers that works every single day, whether you think about it or not. What you can do is not push it harder, but make sure it lacks nothing it needs to do its job normally.

That is also where the logic of a daily dose comes from. Vitamin C and zinc have no large stores in the body: whatever is not used is excreted, and blood levels follow fairly closely what you have taken over the last few days. Vitamin D is the exact opposite. It collects in a reserve that builds up over weeks and empties just as slowly.

And in autumn, here in Romania, that reserve starts to fall.

How Full-immunity works

1. The first hours: what reaches the blood quickly

Vitamin C and zinc are absorbed in the small intestine and reach the blood within two to three hours. White blood cells take up vitamin C and concentrate it well above plasma levels. In a study of seven healthy volunteers on controlled daily doses between 30 and 2,500 mg, neutrophils, monocytes and lymphocytes were already fully saturated at 100 mg a day, at a concentration at least 14 times higher than in plasma (Levine et al., PNAS, 1996). Full-immunity provides 300 mg.

2. The reserve: what builds up over weeks

Vitamin D3 is absorbed together with the fat in your meal, passes into the lymph and reaches the liver, where it becomes 25(OH)D, the storage form the body keeps and activates as it needs it. This reservoir moves slowly: in a study of 67 men who took cholecalciferol daily for roughly 20 winter weeks, the pharmacokinetic model showed a 25(OH)D reservoir that is used up and replenished over about 40 days (Heaney et al., 2003).

3. Defending cells against oxidative stress

Selenium is built into selenoproteins, the enzymes cells use to defend themselves against oxidative stress. Zinc is part of hundreds of enzymes throughout the body. Vitamin C, zinc and selenium contribute to the protection of cells from oxidative stress, and selenium also contributes to the maintenance of normal hair and nails.

4. What the rest of the formula brings

Bovine colostrum is the first secretion of the mammary gland, collected in the first hours after calving and spray-dried at low temperature to preserve the protein fraction. Quercetin is a flavonol found in red onions, apples and capers, extracted here from Sophora japonica buds. Lion's Mane, Hericium erinaceus, is included as a fruiting body extract. You will find all three in the formula with their doses stated on the label: 800 mg, 100 mg and 100 mg.

Who is Full-immunity for?

• For anyone heading into the cold season. From October to March, your skin has no way of producing vitamin D, and whatever you built up over the summer falls month by month.
• For anyone who spends the whole day indoors. Office, home, car, and you catch real daylight at the weekend, if at all.
• For parents heading into autumn with a packed schedule. Nursery, school, school runs, meals eaten standing up.
• For anyone who travels often and eats at times that change from one day to the next.
• For anyone who already has a morning routine and prefers one capsule that covers more, instead of four bottles on the counter.

It is not reserved for any particular group. It is for anyone who does not want the sunless months to catch them unprepared.

Myths about immunity

“Immunity can be boosted”

There is no button. What can be measured is not how “hard” the system is working, but whether it lacks anything it needs to function normally. That is why a serious product talks about nutrients and doses, not intensity.

“One big dose of vitamin C does the same as a small daily one”

It does not. In Levine's study, immune cells were fully saturated at 100 mg a day, and plasma levels rise steeply only between 30 and 100 mg, after which the curve flattens out. Beyond a certain point, whatever extra you take is excreted. The daily rhythm matters more than the size of any single dose.

“If it is sunny in winter, I get enough vitamin D from the sun”

The problem is not the intensity of the light, it is the angle. Below a certain solar angle, UVB radiation is absorbed by the atmosphere before it reaches the skin. In a classic study, in Boston, at 42 degrees north, the skin produced no vitamin D3 at all from November to February, and in Edmonton, at 52 degrees, from October to March (Webb, Kline and Holick, 1988). Romania lies between 44 and 48 degrees.

“More actives automatically means better”

The number on the front tells you nothing if the doses are not written down. A product with twelve ingredients hidden in a proprietary blend gives you less information than one with seven, each with its own milligrams.

What to expect, month by month

Month 1

The fast part happens in the first few days. Vitamin C and zinc reach the blood within a few hours, and because they have no large stores, blood levels settle within the first two to three weeks of daily intake. Vitamin D3 sets off on the long route: meal, lymph, liver, where it is converted into 25(OH)D. Nothing spectacular shows this month, and that is how it should be. The foundation is being laid.

Month 2

Your 25(OH)D level keeps rising from one week to the next. Heaney's figure explains why it takes time: the reservoir is replenished over about 40 days, so after one month you are still only halfway there. Selenium has already been built into selenoproteins, and zinc into the enzymes that were waiting for it.

Month 3 and beyond

This is where the time-dependent part reaches equilibrium. In the same study, each microgram of cholecalciferol taken daily raised the steady-state level by about 0.7 nmol per litre. From December onwards, the daily dose is practically the only source keeping your level stable, until the sun climbs high enough in the sky to take over part of the work again. That is the whole logic: a daily habit, kept up until March.

How to get the most out of Full-immunity

1. Tie it to the same meal, every day. A daily habit attached to something you do anyway keeps itself going. Breakfast is the best hook, because it is also the meal most likely to contain some fat.
2. Do not take it on an empty stomach. Vitamin D is fat-soluble. Without fat in the meal, absorption drops, and the figure on the label stays just that, a figure on the label.
3. Keep it in the morning and leave the evening free. If you want to add something else to your routine, Full-gut fits naturally at lunch, and the evening stays yours.
4. Check your vitamin D level once a year. The most useful moment is at the end of winter, around February or March, when the value is at its yearly low. A 25(OH)D test tells you more than any guess.

How to combine it with other ROOTFUL products

The complete daily ritual: Full-immunity in the morning, with breakfast, Full-gut at lunch, with your midday meal, and Full-calm in the evening, about an hour before bed. The three do not double up on any mineral or vitamin.

The short version: Full-immunity in the morning and Full-calm in the evening. If all you want is one capsule to start the day and one to end it, this is the combination.

Two combinations to avoid. Full-immunity should not be taken together with Vitamin D3 + K2 + A: each of them contains 4,000 IU of vitamin D3, and together you would reach 8,000 IU a day, double the daily limit. Choose one of them, not both. And do not take it on the same day as Full-beauty, because both contain zinc.

Frequently asked questions

All seven actives, with the source, dose and form of each, are on the Full-immunity page. This guide is the first in a series about each product in the capsule range.