Gut Health-the foundation of weight loss: New GLP-1 research may explain why

Over the past 16 years I've worked with thousands of people struggling with gut health issues and problematic weight loss. While many people told me to niche to one focus area, I couldn't let go of my dual passion because I consistently saw the same thing happen.

When gut health improved, weight loss often became easier. People reported fewer cravings, better appetite regulation, improved energy, greater exercise tolerance, and a healthier relationship with food.

To me, the two were never separate goals. They went hand in hand.

What I didn't expect was for a weight loss medication to come along and completely change the conversation around appetite, metabolism, and weight management.

The rise of GLP-1 medications has sparked an explosion of research into the biological factors that influence hunger and weight. Interestingly, some of this research may help explain observations many practitioners have been seeing in clinic for years.

Gut Health Influences More Than Digestion

Most people understand that gut health affects digestion. But its influence extends much further.

The gut plays an important role in:

• Nutrient absorption

• Blood sugar regulation

• Inflammation

• Hormone production

• Appetite and satiety signalling

• Energy production

When these systems are functioning poorly, it becomes much harder to maintain stable energy levels, manage cravings, and regulate body weight.

At its most basic, if you're not digesting and absorbing food effectively, your body may continue sending signals that drive hunger and food seeking behaviour. However, some of the newer research suggests there may be even deeper mechanisms involved.

The Gut Microbe Connection

One of the most fascinating areas of emerging research I've come across involves a gas called hydrogen sulphide.

Hydrogen sulphide is produced naturally in the gut by certain microbes. In normal amounts it plays important roles within the body. However, excess levels may have unintended consequences.

Recent research suggests that high levels of hydrogen sulphide may reduce the body's ability to produce GLP-1, one of the key hormones involved in blood sugar control and appetite regulation.

What Is GLP-1?

GLP-1 (Glucagon-Like Peptide-1) is a hormone produced by specialised cells lining the intestine.

Its roles include:

• Supporting healthy blood sugar control

• Slowing stomach emptying

• Increasing feelings of fullness

• Helping regulate appetite

• And many more

It's also the hormone targeted by many of the newer weight loss medications.

Where Do Mitochondria Fit In?

To understand the research, we need to talk about mitochondria.

Mitochondria are the energy producers of our cells - generating the energy required for cells to function properly.

One mouse study found that hydrogen sulphide produced by gut bacteria reduced GLP-1 levels and appeared to affect how intestinal cells generated energy. Separate research suggests that higher levels of hydrogen sulphide may interfere with mitochondrial function.

One school of thought is that excess hydrogen sulphide could impair the mitochondria within the intestinal cells which are responsible for producing GLP-1. If those cells cannot generate energy efficiently, they may not function optimally, potentially resulting in lower GLP-1 production.

In simple terms, excess hydrogen sulphide may affect the energy-producing machinery of the very cells responsible for producing a hormone that helps regulate appetite and blood sugar. I know right? Mind blown!!!

What Does This Mean?

At this stage, it's important to remember that this is still emerging science. Much of the research has been conducted in animal models, and we don't yet know whether the same mechanisms occur in humans to the same extent.

However, it provides an interesting and biologically plausible explanation for why gut health and weight management may be so closely linked. It also reinforces something I've observed throughout my career:

• Weight loss is rarely just about calories, motivation, willpower, or discipline.

• Gut microbes can influence inflammation, hormone signalling, nutrient absorption, metabolism, and potentially even the pathways involved in appetite regulation.

Could Hydrogen Sulphide SIBO Be Involved?

One condition associated with elevated hydrogen sulphide production is hydrogen sulphide SIBO (Small Intestinal Bacterial Overgrowth).

Common symptoms may include:

• Chronic diarrhoea

• Significant bloating

• Foul-smelling "rotten egg" gas

• Brain fog

• Fatigue

• Sensitivity to high-sulphur foods

Hydrogen sulphide-producing microbes can often be identified through comprehensive stool testing, while hydrogen sulphide breath testing may be used to support diagnosis in appropriate cases.

Final Thoughts

1. The relationship between gut health and weight loss is far more complex than many people realise.

2. While GLP-1 medications have changed the way we think about appetite regulation, the emerging science is also shining a light on the remarkable role our gut microbes may play in shaping metabolism, energy production, and hunger signals.

The best news is that this totally changes how we view weight loss as a community. It's not about just eating less or letting go of 'bad habits'- it's actually about eating more (of the right things) to support good gut health- which in turn could optimise your production of the hormone which naturally regulates your ability to lose weight and keep it off.

This is an area I'll be following closely over the coming years, and I suspect we're only scratching the surface of what we'll eventually discover.

If you're struggling with digestive symptoms, cravings, appetite regulation, or weight loss resistance, please do get in touch - it may be worth looking beyond calories and considering what is happening inside the gut.