A practical Broth & Co guide to gut health, protein, fibre, microbiome metabolites, muscle maintenance, recovery and food-first routines.

Muscle Health Starts With More Than Protein

Protein and resistance exercise remain the foundations of muscle health. But the body still has to digest food, absorb nutrients, regulate glucose, generate energy, manage immune activity and recover from physical stress.

That is why gut health is increasingly part of the muscle conversation. The gut–muscle axis is the relationship between the gastrointestinal system, the gut microbiome and skeletal muscle. It is not a shortcut, and it does not mean changing the microbiome automatically builds muscle. It means the gut is part of the wider system that supports strength, recovery and healthy ageing.

Muscle also communicates with the rest of the body. Muscle as an Endocrine Organ: How Myokines Influence Metabolism, Inflammation & Healthy Ageing explains why muscle is more than tissue that moves the skeleton.

What Is the Gut–Muscle Axis?

The gut–muscle axis describes a two-way relationship. The gut may influence muscle through digestion, nutrient absorption, microbial metabolites, immune activity, inflammation and metabolic signalling. Muscle activity may also influence the gut through movement, glucose use, gut motility and changes linked with exercise.

 

For the broader muscle foundation, see Muscle, Metabolism & Lifelong Health: Why Muscle Matters at Every Age.

Protein Still Matters

Protein provides amino acids used for muscle maintenance, tissue repair, enzymes, hormones, immune proteins and structural tissues. Eating enough protein remains essential, especially with age, training, recovery needs or reduced appetite.

Good protein sources include fish, eggs, poultry, lean meat, dairy foods, soy foods, legumes and useful combinations of plant proteins. Protein quality, distribution across the day and overall energy intake all matter.

Helpful guides include Protein Throughout Life: Why Your Protein Needs Change With Age, High-Protein Foods: The Foundation of Muscle, Healthy Ageing & Recovery Nutrition and Protein Quality vs Quantity: Why Both Matter for Health & Healthy Ageing.

Protein is the building material, but digestion, activity, recovery and the wider metabolic environment help determine how well the body uses it.

The Microbiome Is More Than 'Good Bacteria'

The gut microbiome is often simplified into good bacteria and bad bacteria, but a healthy ecosystem is more complex. Diversity, food supply, microbial metabolites, immune communication and gut barrier function all matter.

One practical way to support the microbiome is to feed it. Fermentable fibres and prebiotic foods provide substrates that gut microbes can use.

 

For more context, read Gut Health Is Not Just About Probiotics: Why Feeding Your Microbiome Matters and The Complete Guide to Gut Biotics..

Short-Chain Fatty Acids: A Gut-to-Body Signal

When gut microbes ferment certain fibres, they can produce short-chain fatty acids such as butyrate, acetate and propionate. These compounds are being studied for roles in gut barrier function, immune regulation, glucose metabolism and inflammatory balance.

This does not mean fibre directly builds muscle. It means fibre-rich foods may help shape a gut environment that is connected with broader metabolic and immune health. In the gut–muscle conversation, that wider environment matters.

Gut Barrier, Inflammation and Recovery

The intestinal lining has a gatekeeping role. It allows nutrients, water and electrolytes to move across while helping regulate exposure to unwanted material within the gut.

Gut barrier function is being investigated in many areas of health. It should be discussed carefully: not every digestive symptom means leaky gut, and intestinal permeability is not the single cause of muscle loss.

A practical way to think about it is this: gut barrier function may be one part of the broader gut, immune and metabolic environment that supports recovery and healthy ageing.

For a detailed explanation, see Leaky Gut, Intestinal Permeability & Gut Barrier Function: The Complete Guide.

Inflammation also needs context. Acute inflammation is part of normal immune defence, repair and exercise adaptation. The concern is persistent low-grade inflammation, which may be associated with poorer recovery, insulin resistance and age-related physical decline. Chronic Inflammation Explained: Diet, Lifestyle, Gut Health & Everyday Wellbeing explains this in a food-first way.

The Gut–Muscle–Mitochondria Connection

Muscle needs energy to contract, recover and adapt. Mitochondria help convert fuel into usable cellular energy, which makes them important for endurance, recovery, metabolic flexibility and physical capacity.

Researchers are investigating how microbial metabolites, immune signalling and inflammatory balance may interact with mitochondrial biology. At the same time, exercise stimulates mitochondrial adaptation and can influence both muscle and metabolic health.

For more, read The Muscle–Mitochondria Connection: How Muscle Supports Energy, Metabolism & Healthy Ageing and Mitochondrial Health: The Missing Link Between Energy, Ageing, Metabolism & Recovery.

Healthy Ageing, Anabolic Resistance and Body Composition

With age, some adults experience anabolic resistance, which means muscle becomes less responsive to normal signals from dietary protein and exercise. This is one reason protein quality, protein distribution, resistance exercise and recovery become more important with age.

Ageing may also bring changes in appetite, digestion, physical activity, immune regulation, microbiome diversity and mitochondrial function. These changes do not act in isolation.

For more, see Anabolic Resistance Explained: Why Building and Maintaining Muscle Gets Harder With Age, Body Composition Explained: Muscle, Fat, Metabolism & Why the Scale Does Not Tell the Whole Story and How to Build a Leaner, Stronger Body: Muscle, Metabolism & Nutrition Through Every Life Stage.

Where Bone Broth Fits

Bone broth can fit into a broader food-first routine focused on protein intake, hydration, meal quality, digestive wellbeing and healthy ageing. It can be used in soups, stews, sauces, rice dishes, noodle bowls or as a warm savoury drink.

Broth & Co Bone Broth provides naturally occurring protein and collagen-associated amino acids. It should complement a varied diet rather than replace complete protein foods such as eggs, fish, dairy foods, meat, poultry, soy foods and balanced plant-protein meals.

For more detail, read Bone Broth Benefits: The Complete Guide to Gut Health, Protein, Recovery & Healthy Ageing, explore Broth & Co Bone Broth or compare Bone Broth vs Collagen vs Protein.

Broth & Co Bone Broth Powder has also been evaluated in a clinical study conducted through the National Institute of Integrative Medicine in Australia. The study looked at digestive wellbeing and markers associated with intestinal permeability in adults with moderate lower gastrointestinal symptoms. These findings should be interpreted in context, but they are relevant to the broader gut health conversation. See Bone Broth Clinical Study: Digestive Wellbeing & Intestinal Permeability Research | Broth & Co.

Where Collagen, Healthy Glow and Skinny Glow Fit

Collagen peptides provide a distinctive amino acid profile rich in glycine, proline and hydroxyproline. These amino acids are associated with collagen-rich tissues such as skin, bone, tendons, ligaments, fascia and connective tissue.

Collagen is not the same as complete dietary protein. For muscle maintenance, complete protein foods remain important. Collagen peptides can complement a routine focused on connective tissue, active lifestyles, skin health, recovery and healthy ageing.

For more, read Collagen Peptides: Benefits for Skin, Joints, Recovery, Gut Health & Healthy Ageing and Collagen Amino Acids Explained: Glycine, Proline & Hydroxyproline.

Healthy Glow may fit into a daily beauty-from-within and collagen routine, while Skinny Glow may be relevant for people considering targeted collagen peptides within a broader metabolic wellness routine. Both should sit alongside meals, movement, sleep and adequate complete protein.

For appetite and metabolic wellness context, see Metabolic Nutrition: Supporting Muscle Health, Satiety & Natural GLP-1 Responses Through Nutrition and The Ozempic Effect with Food: GLP-1 Foods for Satiety, Appetite Control & Blood Sugar Balance.

Exercise: The Other Half of the Axis

Exercise does far more than burn energy. Regular movement supports muscle mass, strength, insulin sensitivity, mitochondrial adaptation, glucose uptake, physical function and metabolic health.

Research also suggests physical activity may influence aspects of the gut microbiome. This is why the gut–muscle axis should never be reduced to supplements alone. Movement is central.

A gym can be useful, but it is not essential. Muscle can be challenged with bodyweight squats, sit-to-stands, resistance bands, wall push-ups, stair climbing, loaded carries, gardening and progressive home-based strength exercises.

For gender-specific routines, see Women, Muscle & Metabolism: How to Build Strength, Improve Body Composition & Support Healthy Ageing and Men, Muscle & Metabolism: How to Build Strength, Improve Body Composition & Support Healthy Ageing.

A Gut–Muscle Supportive Plate

 

A Practical Daily Framework

 

Recipe: Gut–Muscle Bone Broth Bowl

Use this as a flexible template.

Ingredients

·       500 ml prepared Broth & Co bone broth

·       1 serve chicken, tofu, tempeh, eggs, fish or legumes

·       1 cup cooked barley, rice, noodles, quinoa or potatoes

·       1 cup leafy greens

·       1/2 cup mushrooms

·       1/2 cup carrot, pumpkin or zucchini

·       Garlic, ginger, herbs, lemon or lime

·       Extra virgin olive oil, sesame oil, avocado, nuts or seeds

Method

·       Warm the broth with garlic, ginger, herbs or spices.

·       Add vegetables and simmer until tender.

·       Add the protein source and cooked carbohydrate.

·       Finish with herbs, citrus and a small amount of healthy fat.

This style of meal brings together protein, fibre-rich plants, fluid, flavour and warmth. The Power of Soup: How One Pot Can Support Immune Health, Eat More Vegetables & Reduce Food Waste has more soup-based ideas.

Try the Recipes

For practical meals using bone broth, vegetables, herbs, spices and quality ingredients, explore our collection of nourishing recipes.

Mediterranean Bone Broth Recipes

From Australia to Asia: A Journey Through Traditional Soups, Broths & Nourishing Recipes

Latin American Soups, Stews & Comfort Food Recipes with Bone Broth

Eastern European Comfort in a Bowl: Traditional Soups & Stews with Bone Broth

Hawker Bone Broth Recipes

How to Flavour Bone Broth: Herbs, Spices & Gut-Friendly Ingredients

A Well-Stocked Kitchen Is the Secret to Healthy Eating: Effortless Hacks, Smart Staples & Bone Broth Recipes

Healing Soups & Nourishing Broths: Bone Broth Recipes for Recovery

Vegetable-Forward Nourishing Soups

7-Day Bone Broth Meal Plan: Gut Health, Energy & Easy Daily Nutrition

Frequently Asked Questions

What is the gut–muscle axis?

The gut–muscle axis describes the two-way relationship between the gastrointestinal system, gut microbiome and skeletal muscle.

Can poor gut health cause muscle loss?

The relationship is complex. Poor gut health should not be described as a universal direct cause of muscle loss, but researchers are investigating links involving nutrient metabolism, inflammation, ageing and the microbiome.

Do prebiotics build muscle?

Prebiotics do not build muscle directly. They help nourish selected gut microorganisms and may support the broader gut environment.

What are short-chain fatty acids?

Short-chain fatty acids are compounds produced when gut microbes ferment certain fibres. Examples include butyrate, acetate and propionate.

Is bone broth good for muscle health?

Bone broth can contribute protein and collagen-associated amino acids as part of a balanced diet, but complete protein foods remain important for muscle maintenance.

Can collagen build muscle?

Collagen peptides provide glycine, proline and hydroxyproline, but they are not equivalent to complete protein foods for skeletal muscle.

Does exercise affect the gut microbiome?

Research suggests regular physical activity may influence aspects of microbial diversity and function, although responses vary.

What is anabolic resistance?

Anabolic resistance is a reduced muscle-building response to dietary protein and exercise stimuli, and it becomes more common with ageing.

Can you support muscle without a gym?

Yes. Bodyweight exercise, resistance bands, stair climbing, loaded carries and progressive home-based strength exercises can all challenge muscle.

Should I take probiotics for muscle health?

There is not enough evidence to view probiotics as a standalone muscle-support strategy. Protein, resistance exercise, fibre-rich foods, overall diet quality and recovery remain the foundations.

Summary

The gut–muscle axis reminds us that muscle health depends on more than muscle alone. Digestion, protein metabolism, fibre, microbial metabolites, immune signalling, inflammation, mitochondria, exercise and healthy ageing are all connected.

The practical approach is not complicated: eat enough complete protein, include fibre-rich and prebiotic foods, move daily, resistance train, support sleep and recovery, and use bone broth and collagen-rich foods according to their genuine nutritional roles.

Strength, digestive wellbeing, body composition, metabolic health and healthy ageing are not separate stories. They are part of the same whole-body routine.