70% of Your Immune System Is in Your Gut: Why Bone Broth Is Your Winter Shield

1. The "Castle Wall" of Immunity

When we think of immunity, we usually think of white blood cells floating in our veins. However, a large proportion of your immune system—often estimated at around 70%—is actually housed in your intestines, in a network called GALT (Gut-Associated Lymphoid Tissue). Your gut lining is the physical barrier between the outside world (the food and bacteria you swallow) and your internal bloodstream.

Think of your gut lining as the castle wall. If the wall is strong and the mortar between the bricks is intact, the “invaders” (unwanted microbes and particles) are more likely to be contained and flushed out. If that “mortar” is compromised (sometimes described as increased intestinal permeability or “leaky gut” in popular health writing), more material can cross the barrier, keeping your immune system on constant alert and contributing to ongoing inflammation.

2. Why “Granny’s Soup” Was Right All Along

For centuries, bone broth (especially homemade chicken soup) has been nicknamed “Jewish Penicillin.” Our grandmothers did not have microscopes, but they knew that a gelatin-rich broth helped people feel comforted while they recovered. Modern research has explored how certain amino acids found in broths, particularly glycine and arginine, are involved in normal immune and inflammatory responses. Warm, savoury liquids can also help loosen mucus and make it easier to stay hydrated when you do not feel your best.

Beyond the nostalgia, a hot mug of beef or chicken bone broth is an easy way to bring together fluid, electrolytes and easily digestible protein in one cup. Rather than promising a cure for colds or flu, think of it as a traditional food that supports your body when it is under seasonal stress.

3. The “Alkylglycerol” Secret

Bone marrow naturally contains a group of fats called alkylglycerols (AKGs). These lipids are also found in smaller amounts in human milk and certain immune tissues, where they have been studied for their role in normal immune cell function.

Traditional nose-to-tail eating would have included small amounts of these marrow-derived fats from long-simmered bones and joints. Collanature Natural Angus Beef Bone Broth Collagen follows that same whole-food philosophy: it is slowly cooked from Angus beef bones, joints and cartilage, providing collagen in a simple food matrix without added oils or isolated fats.

Rather than treating AKGs as a “magic bullet,” it is more accurate to see them as part of the broader nutritional picture: a mix of proteins, minerals and naturally occurring lipids that your body uses to build and maintain many types of cells, including immune cells. A daily serving of real bone broth is an easy way to include these traditional nose-to-tail nutrients in a modern diet.

4. Maintenance vs. Crisis Management

Most people only think about immunity when they are already sick. They rush to stock up on Vitamin C tablets once the throat starts scratching. However, building a “winter shield” is more like maintaining a castle wall than flipping a switch. It takes time and consistency to support a healthy gut barrier and a well-nourished immune system.

Drinking a cup of Collanature Natural Angus Beef Bone Broth Collagen as part of your daily routine throughout autumn and winter can be a simple way to keep supplying your gut with collagen, minerals and marrow-derived nutrients from the cooking process. It does not replace vaccines, medicines or professional advice, but it can sit alongside them as a steady, food-based habit that supports your body’s natural defences over time.

5. Frequently Asked Questions

1. Can bone broth prevent the flu?

No single food can completely prevent viruses from entering your body or guarantee you will not get sick. What a nutrient-dense diet can do, however, is support the normal functioning of your immune system and help you feel more resilient. Bone broth is best seen as part of a broader winter routine that includes good sleep, stress management, movement and, where appropriate, medical advice and vaccination.

2. Which is better for immunity: chicken or beef?

Traditionally, chicken bone broth has been the go-to choice for colds because it is light, comforting and easy on the stomach. Beef broth from grass-fed cattle, like our Angus bones, tends to be richer in Type III collagen and certain marrow-derived nutrients, making it popular for deeper gut and connective-tissue support. Both can fit into a winter wellness plan; the “best” option is the one you tolerate well and are happy to drink consistently.

3. Should I drink it hot?

Yes, most people find bone broth most pleasant when it is hot or warm. The heat itself can feel soothing, help you relax and support hydration, especially on cold days. A warm mug of broth is also an easy way to replace sugary hot drinks with something savoury and protein-rich.

4. Can I add immune-supporting spices?

Absolutely. Many traditional cuisines combine broth with garlic, ginger and turmeric, all of which are widely studied for their roles in normal immune and inflammatory responses. Adding these to your collagen drink is an easy way to build a personalised “winter mug” that suits your taste while keeping the ingredient list recognisably food-based.

5. Is it suitable for children?

In many cultures, bone broth is a traditional family food and can be used in small amounts in soups, stews or sauces for children. That said, every child is different. If your child has allergies, a medical condition or specific nutritional needs, it is always wise to discuss new foods with your GP, health visitor or paediatric dietitian before making them a daily habit.

Final Thoughts

You cannot control the germs on the train, in the classroom or in the office—but you can influence the strength of your internal defences. By focusing on your gut lining, choosing simple, whole foods and making a daily cup of bone broth part of your winter routine, you give your immune system one more quiet advantage.

Whether you prefer the pure savoury taste of Collanature Natural Angus Beef Bone Broth Collagen or the gently flavoured Collanature Wild Berries Bone Broth Collagen, building your “winter shield” can start with what you put in your cup.