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Ingredient, Explained

Oats and Baker's Yeast in Transfer Factor Max: What the Beta-Glucan Trials Actually Show

Q: Why are oats and baker's yeast in Transfer Factor Max?

Both are sources of beta-glucans, a family of glucose polysaccharides found in the cell walls of yeast, fungi, oats and barley. 4Life's product page lists oats as containing beta-glucans with immunomodulatory effects, tagged as preclinical, and baker's yeast as an ingredient shown in multiple studies to support the immune system. Neither ingredient's amount is disclosed. They sit alongside the four-mushroom Super-Mushroom Blend, IP-6, zinc and vitamins C and D3 as supporting ingredients around the formula's 900 mg of transfer factor peptides.

Q: What is the difference between yeast beta-glucan and oat beta-glucan?

They are structurally different molecules. Yeast and fungal beta-glucans have a beta-1,3 backbone with beta-1,6 branches, a pattern innate immune cells recognize through receptors such as dectin-1 — which is why they are studied for immune effects. Oat and barley beta-glucans are mixed-linkage beta-1,3/1,4 chains with no 1,6 branching; they behave mainly as viscous soluble fiber and are studied for cholesterol and blood-sugar effects, not immunity. The name beta-glucan covers both, but they do different jobs in the body.

Q: Does baker's yeast beta-glucan actually support the immune system?

This is the one supporting ingredient in Transfer Factor Max with a genuinely substantial randomized human trial record. A 2021 systematic review and meta-analysis in the European Journal of Nutrition pooled 13 randomized controlled trials of yeast beta-glucans in healthy people and reported lower incidence, fewer episodes and shorter duration of upper respiratory tract infections versus placebo. Individual trials include a 162-person, 16-week German study at 900 mg per day that reported 25 percent fewer symptomatic cold episodes, and several 250 mg per day studies of a purified baker's-yeast beta-glucan in marathon runners, stressed women and healthy adults. Not every trial was positive: a 299-person trial found no difference in infection incidence, a study in older adults found a non-significant trend, and a 2014 pilot found no effect on immune cell responses. These statements have not been evaluated by the FDA, and no trial tested Transfer Factor Max itself.

Q: How much yeast beta-glucan was used in the clinical trials?

Most positive trials used either 250 mg per day of a purified, standardized baker's-yeast beta-1,3/1,6-glucan extract or 900 mg per day of an insoluble yeast beta-glucan preparation, taken daily for 4 to 16 weeks. The key word is purified: these are cell-wall extracts standardized to a high beta-glucan content, not whole baker's yeast. 4Life lists baker's yeast as an ingredient but does not disclose the amount or whether it is a standardized extract, so the formula cannot be mapped onto any trial dose.

Q: Why does 4Life tag oats as preclinical but not baker's yeast?

Because the evidence records genuinely differ, and the label reflects that. On the 4Life product page, the oats claim — beta-glucans that provide immunomodulatory effects — carries the caret footnote 4Life defines as in preclinical studies. The baker's yeast line — shown in multiple studies to support the immune system — carries no such footnote, which is defensible because randomized human trials of yeast beta-glucan exist. Our editorial view is that this is the right classification for both, with one caveat: the human trials tested purified yeast beta-glucan extracts at defined doses, not whole yeast at an undisclosed amount.

Q: Is the beta-glucan in Transfer Factor Max the same as Wellmune?

Not that anyone can verify. Wellmune is a branded, purified beta-1,3/1,6-glucan derived from a proprietary strain of baker's yeast, and it accounts for many of the 250 mg per day trials. 4Life lists baker's yeast sourced from the USA on the Max product page but does not name a branded extract, a standardization level or an amount. We do not know whether Max contains a purified extract or whole yeast, and this article does not assume either.

Q: Did any yeast beta-glucan trials find no effect?

Yes, and they matter. A 2019 trial in 299 healthy adults taking 900 mg per day for 16 weeks found essentially the same number of people with at least one clinically confirmed upper respiratory infection in each group. A 2017 study in adults aged 50 to 70 taking 250 mg per day for 90 days recorded fewer infections in the beta-glucan group but the difference was not statistically significant. A 2020 trial of a beta-glucan beverage in marathon runners found no difference in episode number or duration. And a 2014 pilot study giving 1,000 mg per day for a week found beta-glucan barely detectable in blood and no change in immune cell cytokine production. The evidence is favorable on balance, not unanimous.

Q: How does oral beta-glucan reach the immune system if it isn't absorbed?

This is a real scientific question, not a settled one. Beta-glucans are large molecules that are not absorbed intact into the bloodstream in meaningful amounts — the 2014 pilot study measured serum levels and found them barely detectable. The proposed pathway is that particulate beta-glucans are taken up by immune cells in the gut lining, particularly in Peyer's patches, and that those cells or their fragments then influence immune activity elsewhere. That mechanism is supported by animal work and is plausible, but the honest position is that clinical trials measured outcomes such as symptom days without fully resolving how the effect occurs.

Q: Can people with yeast or oat sensitivities take Transfer Factor Max?

Anyone with a diagnosed yeast allergy should discuss the product with a healthcare provider before use, since baker's yeast (Saccharomyces cerevisiae) is a listed ingredient. Oats are naturally gluten-free but are frequently processed on shared equipment; 4Life does not publish a gluten-free certification for Max, so people with celiac disease should ask before assuming. More broadly, the formula also contains milk-derived colostrum and egg-derived peptides, which are the more common allergens in the bottle. As always, safety questions belong with your provider, not a supplement label.

TransferFactorMax.com Editorial Updated September 4, 2026 10-min read

TL;DR

Two beta-glucan sources, two different molecules. Yeast beta-glucan (β-1,3/1,6) is the kind immune cells recognize; oat beta-glucan (β-1,3/1,4) is mostly soluble fiber.
Yeast beta-glucan is the best-evidenced supporting ingredient in Max — a 2021 meta-analysis pooled 13 randomized human trials and reported fewer and shorter upper-respiratory episodes vs placebo.*
Not every trial was positive. A 299-person study found no difference in incidence; a 2014 pilot found no immune-cell effect. We cover the misses too.
Oat beta-glucan's human evidence is cardiovascular, not immune — and 4Life's own label tags the oat immune claim preclinical.
Amounts aren't disclosed. Trials used purified extracts at 250–900 mg/day. Max lists "baker's yeast" with no dose. Buy Max for the transfer factors.

Oats and baker's yeast are the two non-mushroom sources of beta-glucan in 4Life Transfer Factor® Max, listed on the product page alongside its 900 mg of transfer factor peptides, the four-mushroom Super-Mushroom Blend, IP-6, zinc, and vitamins C and D3.¹ Both are ordinary food ingredients — oats sourced from Russia, baker's yeast (Saccharomyces cerevisiae) from the USA — included for the beta-glucan polysaccharides in their cell walls. This article explains why those two beta-glucans are structurally different molecules with different research records, walks through the randomized human trials of yeast beta-glucan (including the ones that found nothing), and — as with every ingredient piece on this site — says plainly where the research stops and the bottle begins.*

This completes the series we started with IP-6 and continued with the Super-Mushroom Blend. Those two pieces ended in roughly the same place: real mechanism, thin or extract-specific human data, undisclosed amounts. This one ends somewhere more interesting. For yeast beta-glucan, the human trial record is the strongest of any supporting ingredient in the formula — and the label's confidence about it is, in our reading, earned. The complication is different this time, and it's worth understanding.

Oats & baker's yeast in Max — key facts

The two ingredients: Oats (source: Russia) · Baker's yeast, Saccharomyces cerevisiae (source: USA)¹
Active compounds: Oats: β-1,3/1,4-glucan (mixed-linkage, soluble fiber) · Yeast: β-1,3/1,6-glucan (branched, cell-wall particulate)
Mechanism (yeast): Branched β-1,3/1,6-glucans are recognized by innate immune receptors such as dectin-1 on macrophages and neutrophils²
Human trials (yeast): Yes — 13 RCTs pooled in a 2021 meta-analysis; most at 250 mg or 900 mg/day of a purified extract³
Human trials (oats): Immune: essentially none positive. Cardiovascular: strong — FDA-authorized heart-health claim at 3 g/day soluble oat fiber^12,13
Label classification: Oats: "^ in preclinical studies" · Baker's yeast: "shown in multiple studies" (no preclinical tag)¹
Amounts in Max: Not disclosed for either ingredient; extract vs. whole yeast not stated

Two "beta-glucans" that aren't the same molecule

The word beta-glucan hides a distinction that decides everything else in this article. All beta-glucans are chains of glucose that humans can't digest into sugar. What differs is how the glucose units are linked — and that changes what the molecule does once it's in you.

Yeast and mushroom beta-glucans are built on a β-1,3 backbone with β-1,6 side branches. That branched, particulate structure is what innate immune cells treat as a fungal fingerprint: receptors such as dectin-1 on macrophages, neutrophils and dendritic cells bind it directly.² This is the mechanism behind every immune claim for yeast or mushroom beta-glucan, and it's real.
Oat and barley beta-glucans are mixed-linkage β-1,3/1,4 chains with no 1,6 branching. They dissolve into a viscous gel in the gut and behave as soluble fiber. Their well-established human effects are on cholesterol and post-meal blood sugar, not on immune cells.¹²

So when a label groups "oats and baker's yeast" together as immune polysaccharides, it's pairing one ingredient with a receptor-level immune mechanism and a substantial human trial record with another whose human record is cardiovascular. That's not a criticism of the formula — it's the single most useful thing to understand before reading anything else about it, and almost no affiliate page mentions it.

Yeast beta-glucan — the trials that exist 13 human RCTs

Purified beta-1,3/1,6-glucan from baker's yeast has been studied in randomized, placebo-controlled human trials for over fifteen years, mostly with one outcome in mind: upper respiratory tract infection (URTI) — the researchers' term for cold-like symptoms — in generally healthy people during cold season or after heavy physical stress. Here's the record, favorable first.

The meta-analysis

A 2021 systematic review and meta-analysis in the European Journal of Nutrition pooled 13 randomized controlled trials of yeast beta-glucans in healthy subjects. Compared with placebo, yeast beta-glucan was associated with lower URTI incidence (odds ratio 0.345), fewer URTI episodes, and shorter URTI duration, with improved symptom severity reported in the majority of included trials.³ That's a real pooled finding across real randomized trials — a different tier of evidence from the mouse data behind IP-6 or the single-extract patient studies behind agaricus.

The individual trials worth knowing

Auinger et al., 2013 — 162 healthy adults with a history of recurring colds, randomized to 900 mg/day of an insoluble yeast (1,3)-(1,6)-beta-glucan or placebo for 16 weeks across a German winter. The per-protocol analysis reported 25% fewer symptomatic common-cold episodes in the beta-glucan group (p = 0.041), with milder symptoms during episodes.⁴
Fuller et al., 2012 — 100 healthy adults (mean age ~21), 250 mg/day of a purified baker's-yeast beta-glucan (Wellmune®) or a rice-flour placebo for ~90 days in cold season. The trial measured circulating cytokines and chemokines alongside URTI symptoms and reported differences favoring beta-glucan.⁵
Talbott & Talbott, 2009 and 2012 — two trials of the same 250 mg/day purified extract: one in marathon runners in the weeks after a race, one in women with moderate stress over 12 weeks. Both reported fewer upper-respiratory symptom days and better self-rated mood and vigor versus placebo.^6,7

Notice what these trials share: a purified, standardized cell-wall extract — not whole yeast — at a defined daily dose, taken for one to four months. Keep that in view; it's where this article turns.

The trials that found nothing Read these too

A meta-analysis that pools 13 trials also averages over the ones that didn't work, and an honest ingredient page reports those. Four are worth your time:

Dharsono et al., 2019 — the largest single trial we found: 299 healthy adults, 900 mg/day for 16 weeks. Seventy people in the placebo group and 71 in the beta-glucan group had at least one clinically confirmed URTI — no difference in incidence. Overall severity scores were similar between groups too; the authors reported a severity benefit only in a subgroup.⁸
Fuller et al., 2017 — 250 mg/day in adults aged 50–70 for 90 days. The beta-glucan group logged 17 confirmed URTIs versus 28 on placebo, which sounds decisive until you read the statistics: odds ratio 0.55 with a confidence interval spanning 0.24–1.26, p = 0.149. Not significant. A "strong trend" toward fewer symptom days (p = 0.067) — also not significant.⁹
Mah et al., 2020 — a dairy beverage carrying 250 mg of dispersible yeast beta-glucan, given to marathon runners. No significant differences in URTI episode number or duration versus control, though the insoluble form fared differently from the soluble one.¹⁰
Leentjens et al., 2014 — a small, open-label pilot (15 healthy men) that asked the mechanistic question directly: does 1,000 mg/day of oral beta-glucan for a week change how immune cells respond? Beta-glucan was barely detectable in blood, and neither cytokine production nor microbe-killing activity of white blood cells changed. The authors concluded their data "does not support" oral beta-glucan for enhancing innate immune responses.¹¹

Put it together and the honest summary is: favorable on balance, not unanimous, and the largest single trial was a miss on its primary incidence outcome. The positive signal is concentrated in symptom days and severity rather than in whether you catch something at all. That's a meaningful result for a supplement ingredient — it's also a narrower one than "boosts the immune system" implies.

For once, the label's confidence is earned. The catch is that the trials studied a purified extract at a known dose — and the bottle names an ingredient without either.

How does something you don't absorb do anything?

It's a fair question, and the Leentjens finding — beta-glucan barely detectable in serum — sharpens it. Beta-glucans are large particles that don't enter the bloodstream intact in meaningful amounts. The proposed route is that immune cells in the gut lining, especially in Peyer's patches, engulf the particles, and those cells or their processed fragments then influence immune activity elsewhere in the body. Animal work supports this; the human trials measured downstream outcomes like symptom days without fully resolving the pathway.² A plausible, partially demonstrated mechanism — not a settled one.

Oat beta-glucan — the right molecule for a different job Preclinical (immune)

Oat beta-glucan is one of the best-evidenced food components in nutrition science. The FDA authorized a health claim in 1997 — still in force — that 3 grams per day of soluble fiber from whole oats, as part of a diet low in saturated fat and cholesterol, may reduce the risk of heart disease, on the strength of its cholesterol-lowering effect.¹³ That claim is about β-1,3/1,4-glucan acting as viscous fiber. It is not an immune claim.

What about immunity? The mechanism is weaker on paper — the mixed-linkage structure is a poor fit for dectin-1 compared with the branched yeast form — and the human data reflects it. The best-known trial gave trained cyclists 5.6 grams of oat beta-glucan daily for two weeks around a three-day block of heavy riding and tracked immune measures and URTI symptoms for two more weeks. Result: no difference from placebo on any immune marker or on URTI incidence.¹² Several grams of oat beta-glucan per day, delivered as a beverage, did nothing measurable — and no capsule formula contains anything close to that amount.

The oat immune story lives in cell and animal studies. And here 4Life's label is, to its credit, accurate: on the Max product page the oats claim — "contains beta glucans that provide immunomodulatory effects in the body" — carries the caret 4Life defines as "in preclinical studies."¹ The baker's yeast line — "shown in multiple studies to boost the immune system" — carries no such tag. The manufacturer drew the same line the literature draws. We'd draw it in exactly the same place.

Where the evidence stands, side by side

Oats vs. baker's yeast — evidence, honestly tiered

	Baker's yeast β-glucan	Oat β-glucan
Structure	β-1,3 backbone, β-1,6 branches (particulate)	Mixed-linkage β-1,3/1,4 (soluble, viscous)
Immune mechanism	Dectin-1 / innate receptor recognition — well characterized	Weak receptor fit; mostly fiber effects
Human immune RCTs	13 pooled in a 2021 meta-analysis; favorable on incidence, episodes, duration	One notable trial (5.6 g/day, athletes) — null
Null / negative trials	Yes — 299-person incidence trial, older-adult trial, beverage trial, 2014 pilot	The one notable trial was null
Best human evidence overall	Immune / URTI symptoms	Cardiovascular — FDA-authorized heart-health claim at 3 g/day
Doses in positive trials	250 mg/day (purified extract) · 900 mg/day (insoluble prep)	3 g/day for the cholesterol claim
4Life label classification	"Shown in multiple studies" — no preclinical tag	"^ In preclinical studies"
Amount in Max	Not disclosed	Not disclosed

Evidence labels are our editorial team's plain-language assessment, not formal scientific grades. "URTI" is the trial literature's term for upper respiratory tract infection symptoms; reporting what trials measured is not a claim that any product prevents illness. 4Life's per-ingredient label classifications are quoted from the Max product page.¹

The gap between the trials and the bottle

Here's the complication we promised. Every positive yeast trial above used a purified beta-glucan extract — yeast cell walls processed to remove protein, lipid and mannan, and standardized to a high beta-glucan content. Wellmune® alone accounts for several of the 250 mg trials, and it is a specific branded extract from a proprietary strain of baker's yeast.^5–7 The 900 mg trials used a different, insoluble preparation.^4,8

The Max product page lists "baker's yeast."¹ It does not say whether that means whole dried yeast, yeast cell wall, or a standardized beta-glucan extract; it does not name a brand; and it does not give an amount. Whole baker's yeast contains beta-glucan, but only as a fraction of its dry weight, so the same milligrams of whole yeast and of purified extract deliver very different quantities of the active molecule. Without the form and the dose, there is no way to place Max on the 250-to-900 mg scale the trials established — the same disclosure limitation we flagged for IP-6 and the mushrooms, applied to the one ingredient where the trial dose would actually be worth matching.

Two things are true at once, then. 4Life's claim that baker's yeast has been shown in multiple studies to support immune function is accurate — more accurate than most supplement-label claims we've checked on this site. And whether the amount and form in Max resemble what those studies tested is unknown, because it isn't published. A label can be honest and still leave the most practical question unanswered.

So how should you think about the beta-glucans in Max?

Our read, consistent with the rest of this series: yeast beta-glucan is the best-supported supporting ingredient in the formula, and it's still not the reason to buy it.

The reason to buy Transfer Factor Max — or not — is its 900 mg of colostrum-, egg- and plant-derived transfer factor peptides, where the product-specific evidence sits, including the peer-reviewed Yu 2024 trial we walk through in our breakdown of the clinical studies.¹⁴ The yeast beta-glucan is a genuinely well-chosen addition with a real mechanism and a real (if imperfect) human record. The oats are a reasonable fiber ingredient whose immune role is preclinical, exactly as the label says.

If research-dosed yeast beta-glucan is specifically what you're after, a standalone product standardized to 250 mg or 900 mg of β-1,3/1,6-glucan matches the trials far more closely than any undisclosed inclusion in a multi-ingredient capsule. If you're buying Max, buy it for the transfer factors — and count the yeast as the one extra where the label's confidence is backed by actual human trials.*

For the full ingredient-by-ingredient breakdown, see what's inside Transfer Factor Max. For the proposed mechanism behind the transfer factors themselves — Recognize, Respond, Remember, Renew — see the science page, and our FAQ covers dosing and daily-use questions. Yeast and milk/egg allergen questions are covered in our safety and interactions guide.

Frequently asked questions

Why are oats and baker's yeast in Transfer Factor Max?

Both are sources of beta-glucans — glucose polysaccharides found in the cell walls of yeast, fungi, oats and barley. 4Life's product page lists oats as containing beta-glucans with immunomodulatory effects (tagged preclinical) and baker's yeast as an ingredient shown in multiple studies to support the immune system. Neither amount is disclosed. They sit alongside the four-mushroom Super-Mushroom Blend, IP-6, zinc and vitamins C and D3 as supporting ingredients around the formula's 900 mg of transfer factor peptides.

What is the difference between yeast beta-glucan and oat beta-glucan?

They're structurally different molecules. Yeast and fungal beta-glucans have a β-1,3 backbone with β-1,6 branches — a pattern innate immune cells recognize through receptors such as dectin-1, which is why they're studied for immune effects. Oat and barley beta-glucans are mixed-linkage β-1,3/1,4 chains with no 1,6 branching; they act mainly as viscous soluble fiber and are studied for cholesterol and blood-sugar effects, not immunity. Same name, different jobs.

Does baker's yeast beta-glucan actually support the immune system?

This is the one supporting ingredient in Max with a substantial randomized human trial record. A 2021 meta-analysis in the European Journal of Nutrition pooled 13 RCTs of yeast beta-glucans in healthy people and reported lower incidence, fewer episodes and shorter duration of upper respiratory tract infections versus placebo. Individual trials include a 162-person, 16-week study at 900 mg/day reporting 25% fewer symptomatic cold episodes, and several 250 mg/day trials of a purified baker's-yeast extract in runners, stressed women and healthy adults. Not every trial was positive — a 299-person trial found no difference in incidence, an older-adult study found a non-significant trend, and a 2014 pilot found no immune-cell effect. No trial tested Transfer Factor Max itself.*

How much yeast beta-glucan was used in the clinical trials?

Most positive trials used either 250 mg/day of a purified, standardized baker's-yeast β-1,3/1,6-glucan extract or 900 mg/day of an insoluble yeast beta-glucan preparation, daily for 4–16 weeks. The key word is purified: these are cell-wall extracts standardized to high beta-glucan content, not whole yeast. 4Life lists baker's yeast but doesn't disclose the amount or whether it's a standardized extract, so the formula can't be mapped onto any trial dose.

Is there human evidence that oat beta-glucan supports immunity?

Very little. Oat beta-glucan's strong human evidence is cardiovascular — the FDA has authorized a claim that 3 g/day of soluble fiber from whole oats may reduce heart-disease risk. The immune data is mostly cell and animal work. The best-known human immune trial gave endurance cyclists 5.6 g of oat beta-glucan daily around heavy training and found no effect on immune measures or URTI incidence. 4Life's label is consistent with this: it tags the oat immune claim as preclinical.

Why does 4Life tag oats as preclinical but not baker's yeast?

Because the evidence records differ, and the label reflects that. On the Max product page, the oats claim carries the caret 4Life defines as "in preclinical studies." The baker's yeast line — "shown in multiple studies" — carries no such footnote, which is defensible because randomized human trials of yeast beta-glucan exist. Our view is that both classifications are correct, with one caveat: the human trials tested purified yeast beta-glucan extracts at defined doses, not whole yeast at an undisclosed amount.

Is the beta-glucan in Transfer Factor Max the same as Wellmune?

Not that anyone can verify. Wellmune® is a branded, purified β-1,3/1,6-glucan from a proprietary strain of baker's yeast and accounts for many of the 250 mg/day trials. 4Life lists "baker's yeast" sourced from the USA but doesn't name a branded extract, a standardization level or an amount. We don't know whether Max contains a purified extract or whole yeast, and this article doesn't assume either.

Did any yeast beta-glucan trials find no effect?

Yes, and they matter. A 2019 trial in 299 healthy adults (900 mg/day, 16 weeks) found essentially the same number of people with at least one confirmed URTI in each group. A 2017 study in adults 50–70 (250 mg/day, 90 days) recorded fewer infections on beta-glucan, but not significantly so. A 2020 beverage trial in marathon runners found no difference in episode number or duration. And a 2014 pilot (1,000 mg/day, one week) found beta-glucan barely detectable in blood and no change in immune-cell cytokine production. Favorable on balance — not unanimous.

How does oral beta-glucan reach the immune system if it isn't absorbed?

A real question, not a settled one. Beta-glucans are large molecules that aren't absorbed intact into the bloodstream in meaningful amounts — the 2014 pilot measured serum levels and found them barely detectable. The proposed pathway is uptake by immune cells in the gut lining, particularly in Peyer's patches, with those cells or their fragments then influencing immune activity elsewhere. That's supported by animal work and plausible, but the clinical trials measured outcomes like symptom days without fully resolving the mechanism.

Can people with yeast or oat sensitivities take Transfer Factor Max?

Anyone with a diagnosed yeast allergy should talk to a healthcare provider before use, since baker's yeast (Saccharomyces cerevisiae) is a listed ingredient. Oats are naturally gluten-free but are often processed on shared equipment, and 4Life doesn't publish a gluten-free certification for Max — so people with celiac disease should ask before assuming. The formula's more common allergens are the milk-derived colostrum and egg-derived peptides; see our safety guide. Safety questions belong with your provider, not a label.

Are the beta-glucan sources the reason to buy Transfer Factor Max?

No. Yeast beta-glucan is arguably the best-evidenced supporting ingredient in the formula, but its trials used purified extracts at defined doses that Max doesn't disclose or match. The case for Max rests on its 900 mg of colostrum-, egg- and plant-derived transfer factor peptides, where the product-specific evidence sits, including the peer-reviewed Yu 2024 trial. If research-dosed yeast beta-glucan is specifically what you want, a standalone 250 mg or 900 mg standardized product is the closer match.

What are beta-glucans, in plain English?

Long chains of glucose that form part of the cell walls of yeast, mushrooms, oats and barley. Unlike starch, humans can't digest them into sugar. Depending on how the glucose units are linked, they either act as soluble fiber in the gut (the oat and barley type) or present a molecular pattern immune cells recognize as fungal (the yeast and mushroom type). Max contains both: oats on one side, and baker's yeast plus the four-mushroom blend on the other.

References

4Life Transfer Factor Max product page and Product Information Sheet, 4life.com. Ingredient list, source countries, the oats claim tagged "^ In preclinical studies," and the baker's yeast line "has been shown in multiple studies to boost the immune system." Accessed September 4, 2026.
Effects of fungal beta-glucans on health — a systematic review of randomised controlled trials. Food & Function, 2021. Mechanism via dectin-1 recognition of β-1,3/1,6-glucans; discussion of gut-associated uptake; overall RCT evidence limited by heterogeneity.
Effects of yeast β-glucans for the prevention and treatment of upper respiratory tract infection in healthy subjects: a systematic review and meta-analysis. European Journal of Nutrition, 2021. 13 RCTs; URTI incidence OR 0.345 (95% CI 0.192–0.620); fewer episodes (SMD −0.315); shorter duration (SMD −0.312).
Auinger, A., et al. (2013). Yeast (1,3)-(1,6)-beta-glucan helps to maintain the body's defence against pathogens: a double-blind, randomized, placebo-controlled, multicentric study in healthy subjects. European Journal of Nutrition, 52(8), 1913–1918. n=162; 900 mg/day insoluble yeast β-glucan for 16 weeks; 25% fewer symptomatic common-cold episodes per protocol (p=0.041).
Fuller, R., et al. (2012). Influence of yeast-derived 1,3/1,6 glucopolysaccharide on circulating cytokines and chemokines with respect to upper respiratory tract infections. Nutrition, 28(6), 665–669. n=100 healthy adults; 250 mg/day Wellmune® vs rice-flour placebo, ~90 days.
Talbott, S., & Talbott, J. (2009). Effect of BETA 1,3/1,6 GLUCAN on upper respiratory tract infection symptoms and mood state in marathon athletes. Journal of Sports Science & Medicine, 8(4), 509–515. 250 or 500 mg/day post-marathon; fewer URTI symptom days and better mood vs placebo.
Talbott, S.M., & Talbott, J.A. (2012). Baker's yeast beta-glucan supplement reduces upper respiratory symptoms and improves mood state in stressed women. Journal of the American College of Nutrition, 31(4), 295–300. 250 mg/day, 12 weeks.
Dharsono, T., et al. (2019). Effects of yeast (1,3)-(1,6)-beta-glucan on severity of upper respiratory tract infections: a double-blind, randomized, placebo-controlled study in healthy subjects. Journal of the American College of Nutrition, 38(1), 40–50. n=299; 900 mg/day, 16 weeks; 70 (placebo) vs 71 (β-glucan) subjects with ≥1 confirmed URTI; overall severity similar between groups.
Fuller, R., et al. (2017). Yeast-derived β-1,3/1,6 glucan, upper respiratory tract infection and innate immunity in older adults. Nutrition, 39–40, 30–35. Adults 50–70; 250 mg/day, 90 days; 17 vs 28 URTIs (OR 0.55, 95% CI 0.24–1.26, p=0.149); symptom-day trend p=0.067.
Mah, E., et al. (2020). Soluble and insoluble yeast β-glucan differentially affect upper respiratory tract infection in marathon runners: a double-blind, randomized placebo-controlled trial. Journal of Medicinal Food, 23(4). 250 mg/day dispersible yeast β-glucan in a dairy beverage; no significant difference in URTI episode number or duration vs control.
Leentjens, J., et al. (2014). The effects of orally administered beta-glucan on innate immune responses in humans, a randomized open-label intervention pilot-study. PLOS ONE, 9(9), e108794. n=15 healthy men; 1,000 mg/day for 7 days; β-glucan barely detectable in serum; no change in leukocyte cytokine production or microbicidal activity.
Nieman, D.C., et al. (2008). β-Glucan, immune function, and upper respiratory tract infections in athletes. Medicine & Science in Sports & Exercise, 40(8), 1463–1471. Trained cyclists; 5.6 g/day oat β-glucan vs placebo around 3 days of 3-hour rides; no effect on immune measures or URTI incidence.
U.S. Food and Drug Administration. 21 CFR §101.81 — Health claims: soluble fiber from certain foods and risk of coronary heart disease. Authorizes the claim for 3 g/day of β-glucan soluble fiber from whole oats (authorized 1997; amended subsequently).
Yu, L., Iloba, I., Cruickshank, D., & Jensen, G.S. (2024). Feasibility trial exploring immune-related biomarkers after consuming a nutraceutical supplement containing colostrum- and egg-based low-molecular-weight peptides. Current Issues in Molecular Biology, 46, 6710–6724. Peer-reviewed; concerns the transfer factor peptides, not the beta-glucan ingredients.

*These statements have not been evaluated by the Food and Drug Administration. Transfer Factor Max is a dietary supplement and is not intended to diagnose, treat, cure, or prevent any disease. This article summarizes published third-party research on yeast- and oat-derived beta-glucans for educational purposes; it is not medical advice and does not represent a health claim about any product. The trials discussed tested specific purified beta-glucan preparations at defined doses — not Transfer Factor Max — and their reported outcomes (upper respiratory tract infection incidence, episodes, duration and symptoms) are described to characterize the ingredient literature, not to suggest that this or any dietary supplement prevents, treats or cures colds, influenza or any other illness. The FDA oat-fiber health claim referenced concerns dietary soluble fiber intake from whole oats at 3 g/day and is not a claim about this product. "Evidence" labels are the editorial team's plain-language assessment, not formal scientific grades. Individual results vary. Consult your healthcare provider before beginning any new supplement program, particularly if pregnant, nursing, taking medication (including immunosuppressants), managing an autoimmune condition, or allergic to yeast, milk or egg.