Insulin resistance often shows up alongside weight gain, and many of the people I work with don’t realise how closely the two are linked. When insulin resistance improves, clients usually feel better, lose weight more steadily and have more energy for their workouts.
There’s a lot of debate about whether high-protein diets help or harm insulin sensitivity. I’ll break down a recent study in plain language and share how I apply the findings in real coaching situations.
Understanding insulin resistance in real life
Insulin resistance happens when your body doesn’t respond to insulin like it should. Muscles struggle to absorb glucose, so the body produces more insulin to compensate. Over time this can lead to weight gain, low energy and a higher risk of type 2 diabetes.
Many clients feel stuck in this cycle — tired, frustrated and unsure what actually works. One of the most effective ways to improve sensitivity is sensible weight loss combined with habits that support muscle and steady energy.
The debate about protein and insulin resistance
Some research suggests higher protein — especially animal protein — could reduce insulin sensitivity. Other studies say the opposite. On top of that, plant-based and animal proteins might have different effects.
It’s often hard to know what’s doing the work because many high-protein plans also change carbs or fats. That’s why controlled studies help — they try to isolate the protein effect.
What the study looked at
Researchers ran a one-month randomised trial with adults who were obese and insulin resistant. Participants followed a calorie-controlled eating plan and were split into four groups:
- Normal protein (mostly animal)
- Normal protein (mostly plant)
- High protein (mostly animal)
- High protein (mostly plant)
The study measured weight, waist size, body composition, blood glucose and insulin markers, triglycerides and inflammation before and after the month-long plan.
What actually improved
All groups lost weight and improved insulin sensitivity — which shows how powerful consistent, structured eating is.
The biggest changes were in the high-protein groups:
- High-protein (animal): ~92% improvement in insulin markers
- High-protein (plant): ~60% improvement
Those high-protein groups also saw lower body fat, better triglycerides, reduced inflammation and increased muscle mass. The researchers concluded that a hypocaloric, high-protein diet can improve insulin sensitivity rapidly, and that the protein source didn’t appear to change that improvement.
What this means for everyday people
High-protein diets may help insulin resistance — but protein is only one piece of the puzzle. From my coaching experience, these points matter most:
1. Energy intake that matches your goals
You don’t need to starve. A structured calorie plan that’s realistic for your life makes a massive difference.
2. Enough protein to preserve muscle and reduce hunger
Protein helps with cravings and keeps energy steadier between meals — that helps you stick to the plan.
3. Movement you can keep doing
Strength work, boxing, or walking regularly helps muscles use glucose more effectively and supports long-term improvements.
4. Support and accountability
Most people don’t lack knowledge — they lack consistent support. That’s why I keep things simple, flexible and encouraging.
What the study doesn’t tell us yet
There are limitations. The insulin tests used aren’t the absolute gold standard, and the study ran for just one month. It wasn’t fully clear whether the benefit came from the higher protein specifically or from how the whole diet shifted.
Longer studies and more precise testing would help confirm the result, but what we have is useful: a high-protein, calorie-controlled approach produced fast improvements in insulin markers in people with obesity and insulin resistance.
My take as a coach
I don’t push extreme diets. When someone comes to me with insulin resistance, weight concerns or low confidence, I focus on:
- Simple nutrition with enough protein
- Realistic meal ideas that fit your life
- Safe, technique-focused training
- Habits that are built slowly and stick
When people feel supported and understood, their health improves in ways a study can’t always measure.
If you’d like help putting together a simple plan that fits your day-to-day, I’m here and I’d love to help.
