17 Tháng 6, 2026

IgG Immunoglobulins Explained: Why They Matter for Your Immune System

When people look at the label on Alpha Lipid Lifeline® (sữa non alpha), one number stands out: 300mg of immunoglobulins per serving. But what exactly are immunoglobulins? What do they do in the body? And why does it matter how much of them are in your colostrum supplement?

This article explains immunoglobulins — and IgG in particular — in simple, clear language so you can understand exactly what you are taking and why it works.

What are immunoglobulins?

Immunoglobulins are antibodies — specialised proteins produced by your immune system. Their job is to identify, bind to, and neutralise foreign substances that enter your body, including bacteria, viruses, fungi, and toxins.

Think of immunoglobulins as your body's security identification system. Every pathogen — every harmful bacteria or virus — has a unique surface structure called an antigen. Immunoglobulins are shaped specifically to recognise and lock onto these antigens, like a key fitting a lock. Once an immunoglobulin binds to a pathogen, it either neutralises it directly or flags it for destruction by other immune cells.

Without immunoglobulins, your immune system would have no way to identify threats specifically — it would be like trying to stop intruders without being able to tell them apart from guests.

The five types of immunoglobulins

There are five main classes of immunoglobulins in the human body, each with a different role:

Type	Where found	Primary role
IgG	Blood and tissues — most abundant (75% of all antibodies)	Long-term immune memory, neutralising pathogens, crossing the placenta to protect newborns
IgA	Mucous membranes — gut, lungs, saliva, tears	First-line defence at body surfaces — stops pathogens before they enter the bloodstream
IgM	Blood — first antibody produced in an infection	Rapid early immune response before IgG takes over
IgE	Blood and tissues	Allergic responses and defence against parasites
IgD	Surface of B cells	Activates B cells to begin producing other antibodies

Bovine colostrum — including the colostrum in Alpha Lipid Lifeline® — is particularly rich in IgG, IgA, and IgM. IgG is by far the most abundant, making up the majority of the immunoglobulin content in colostrum.

What does IgG do in the body?

IgG is the most important and versatile immunoglobulin. It is the primary antibody in the body's long-term immune memory and carries out several critical functions:

1. Neutralising pathogens directly

IgG binds directly to bacteria, viruses, and toxins — physically blocking them from attaching to and entering your cells. A virus that cannot attach to a cell cannot infect it. IgG is particularly effective against respiratory pathogens (influenza, coronaviruses, rhinoviruses) and gastrointestinal pathogens (E. coli, Salmonella, Rotavirus).

2. Activating the complement system

When IgG binds to a pathogen, it can trigger the complement system — a cascade of proteins that punch holes in bacterial cell membranes, killing the bacteria directly. This is one of the most powerful pathogen-destruction mechanisms in the immune system.

3. Opsonisation — flagging pathogens for destruction

IgG coats pathogens in a process called opsonisation, which marks them for destruction by phagocytes (immune cells that engulf and destroy pathogens). Bovine IgG binds to human Fc receptors on phagocytes, which enhances phagocytosis and the killing of bacteria — making the immune response faster and more efficient.

4. Immune memory

After you recover from an infection or receive a vaccine, your immune system produces IgG antibodies specific to that pathogen. These IgG antibodies remain in your bloodstream for months to years, giving your immune system the memory to respond much faster if the same pathogen appears again. This is the foundation of long-term immunity.

5. Protecting the gut

IgG in the gut lining helps maintain the gut barrier function by binding to pathogens before they can penetrate the intestinal wall. Research published in Frontiers in Nutrition confirms that bovine IgG can prevent gastrointestinal tract infections and LPS-induced inflammation, supporting gut barrier integrity.

Why does IgG decline as we age?

The human immune system reaches its peak performance in early adulthood and then gradually declines — a process called immunosenescence. This means the body produces fewer and less effective immunoglobulins as we get older.

After the age of 50, several changes happen:

The bone marrow produces fewer B cells — the immune cells that make antibodies
Existing B cells become less responsive to new threats
IgG antibody responses to new infections are slower and weaker
Immune memory becomes less reliable — meaning past immunity fades faster
The gut's secretory IgA declines — reducing first-line mucosal protection

This is why older adults get sicker more easily, take longer to recover, and respond less effectively to vaccines compared to younger people. It is not a lifestyle problem — it is a fundamental biological change in immune function with age.

This is also one of the most compelling reasons adults over 50 take bovine colostrum supplements — because colostrum provides a concentrated, external source of the immunoglobulins the body is producing less of naturally.

How bovine IgG works in the human body

A common question is: can bovine (cow) antibodies actually work in the human body? The answer is yes — and here is why.

A 2025 review published in Animal Advances by researchers at the Jiangsu Academy of Agricultural Sciences confirmed that bovine colostrum contains elevated concentrations of immunoglobulins — particularly IgG, IgA, and IgM — that provide passive immunity against bacterial, viral, and enteric pathogens in humans.

Bovine IgG has broad binding capabilities against a wide variety of human intestinal, respiratory, and viral pathogens. Research published in Frontiers in Nutrition reviewed multiple studies in infants and adults and found that bovine IgG can prevent gastrointestinal tract infections, upper respiratory tract infections, and LPS-induced inflammation.

The mechanism is passive immunity — the same principle as a newborn receiving protective antibodies from its mother's colostrum. The bovine IgG does not permanently reprogram your immune system; instead it provides a direct supply of functional antibodies that act immediately in the gut and bloodstream.

Why delivery matters: the IgG absorption problem

Here is the critical challenge that most colostrum supplements do not adequately address: IgG is a large, fragile protein molecule. The adult digestive system — with its strong stomach acid and digestive enzymes — is very efficient at breaking down proteins, including IgG.

A 2024 study published in Food Function (Royal Society of Chemistry) studied the bioavailability of immunoglobulin G from bovine colostrum in vivo and found that standard colostrum preparations have low bioavailability of immune active substances, which may significantly reduce their immunoregulatory function. The study found that encapsulating bovine colostrum with liposomes enabled sustained release of IgG and significantly increased IgG blood serum concentrations — confirming that liposomal delivery dramatically improves IgG absorption.

This research directly validates the science behind the Alpha Lipid™ liposomal delivery system used in Alpha Lipid Lifeline®. By encapsulating the colostrum — including its IgG — in a phospholipid bi-layer, Alpha Lipid™ protects the fragile IgG molecules from stomach acid and delivers them intact to the small intestine, where they are absorbed into the bloodstream. New Image International's processing retains over 90% of active immunoglobulins — a level most standard colostrum products cannot achieve.

In practical terms: 300mg of protected IgG in Alpha Lipid Lifeline® delivers significantly more functional immune benefit than the same or higher amount of unprotected IgG in a standard colostrum capsule.

IgG, IgA, and IgM in Alpha Lipid Lifeline® — what each one does

Alpha Lipid Lifeline® contains all three main immunoglobulins found in bovine colostrum:

IgG (Immunoglobulin G) — 300mg per serving

The primary immune antibody. Neutralises pathogens in the bloodstream and tissues, activates the complement system, flags pathogens for destruction, and supports gut barrier function. IgG is the body's long-term immune workhorse — and the most depleted as we age.

IgA (Immunoglobulin A)

The frontline mucosal antibody. Found on the surfaces of the gut, lungs, mouth, and nose. IgA stops pathogens at the point of entry — before they penetrate into the body. Secretory IgA in colostrum coats the gut lining and provides direct local immune protection in the digestive tract.

IgM (Immunoglobulin M)

The rapid-response antibody. IgM is the first antibody produced when the immune system encounters a new threat. It provides immediate, non-specific immune activation while IgG takes over for the more targeted, sustained response.

Together, IgG, IgA, and IgM work as a coordinated immune defence system — each operating at a different stage and location of the immune response.

Who benefits most from supplementing with IgG colostrum?

A 2025 review in Animal Advances concluded that bovine colostrum is particularly valuable for vulnerable groups including infants, children, the elderly, and immunocompromised patients. Based on the clinical evidence, the people most likely to notice a significant benefit from the IgG in Alpha Lipid Lifeline® are:

Adults over 50 — whose natural IgG production and immune memory are declining
The elderly — who are most vulnerable to respiratory and gastrointestinal infections
People who get sick frequently — suggesting an underlying immune deficiency that IgG supplementation can help address
People recovering from illness or surgery — whose immune reserves have been depleted
People with gut permeability issues — where reduced gut IgA allows pathogens to enter the bloodstream more easily
Frequent travellers — regularly exposed to new pathogens their immune system has no IgG memory for
People under chronic stress — which suppresses IgG production and reduces immune response effectiveness

How much IgG is in Alpha Lipid Lifeline®?

Each serving of Alpha Lipid Lifeline® contains:

1,600mg of bovine colostrum — sourced from New Zealand pasture-fed cows
300mg of immunoglobulins — primarily IgG, with IgA and IgM
Delivered via the patented Alpha Lipid™ liposomal system for maximum absorption
Processed at low temperature to retain over 90% of active immunoglobulins

This combination — high IgG concentration plus proven liposomal delivery — is what distinguishes Alpha Lipid colostrum (sữa non alpha) from standard colostrum products that may list similar or higher amounts of colostrum on the label but deliver a fraction of the functional IgG to where it is needed.

Frequently asked questions about IgG and colostrum

Does the IgG in bovine colostrum survive digestion?

In standard colostrum products, a significant portion of IgG is broken down by stomach acid before reaching the intestine. In Alpha Lipid Lifeline®, the IgG is protected by the Alpha Lipid™ liposomal coating, which shields it from stomach acid and allows it to be absorbed in the small intestine. Research in Food Function (2024) directly confirmed that liposomal encapsulation significantly increases IgG blood serum concentrations after supplementation.

Is bovine IgG safe to consume?

Yes. Bovine colostrum and its immunoglobulins have been consumed by humans for centuries and studied extensively in clinical trials. For most adults, bovine IgG is safe and well-tolerated. People with a milk protein allergy (casein allergy) should consult their doctor before use, as colostrum is a bovine dairy product.

How long does it take for IgG supplementation to have an effect?

IgG from colostrum is absorbed relatively quickly — within hours of consumption. However, the most noticeable immune benefits — particularly fewer colds and faster recovery — typically become apparent after 4 to 8 weeks of consistent daily use, as the cumulative effect of regular IgG supplementation builds up in the body's mucosal surfaces and gut lining.

Can I take Alpha Lipid Lifeline® during an illness?

Yes — and many users report that continuing to take Alpha Lipid Lifeline® during illness helps them recover faster. The IgG provides direct immune support during the infection, while the lactoferrin in the colostrum has direct antimicrobial properties. As always, consult your doctor for any serious illness.

Where to buy Alpha Lipid Lifeline® (sữa non alpha) in Australia

Alpha Lipid Lifeline® is available exclusively through authorised New Image International distributors — not in supermarkets or pharmacies.

Alipid (alipid.com.au) is one of Australia's largest official distributors, offering genuine product at the lowest authorised prices, with fast shipping across Australia and internationally to the USA, Canada, and worldwide.

Single can (450g, approx. 28 serves): $87 AUD
6-can pack: $498 AUD ($83/can)
12-can pack: $960 AUD ($80/can)
Phone: 0451 667 789
Rated 4.9/5 by verified Australian customers

→ Shop Alpha Lipid Lifeline® at Alipid

Summary

Immunoglobulins are antibodies — proteins your immune system uses to identify, neutralise, and destroy pathogens
IgG is the most abundant immunoglobulin — making up 75% of all antibodies — and is responsible for long-term immune memory, pathogen neutralisation, and gut barrier protection
IgG production naturally declines with age, leaving adults over 50 with a weaker, slower immune response
Bovine colostrum is one of the richest natural sources of IgG available — with broad binding capability against human intestinal, respiratory, and viral pathogens
Standard colostrum products lose significant IgG to stomach acid before absorption — the Alpha Lipid™ liposomal delivery system in Alpha Lipid Lifeline® solves this, confirmed by a 2024 peer-reviewed study in Food Function
Alpha Lipid Lifeline® (sữa non alpha) delivers 300mg of protected immunoglobulins per serving — with over 90% of active IgG retained through New Image International's low-temperature processing

References: Nasiru et al., Animal Advances (2025); Zhou et al., Food Function, Royal Society of Chemistry (2024); Umar et al., Future Foods (2024); Palmeira & Carneiro-Sampaio, Frontiers in Nutrition (2018); ScienceDirect Bovine Colostrum Therapeutic Potential Review (2024).

Alipid is an official Australian distributor of Alpha Lipid Lifeline®, manufactured by New Image International, New Zealand. This article is for informational purposes only and does not constitute medical advice. Please consult your healthcare provider before starting any new supplement.