The rise of GLP-1 medications like Ozempic, Wegovy, and Mounjaro has changed the game for weight loss. These powerful drugs, originally developed for type 2 diabetes, are now helping people shed significant amounts of weight—often very quickly.

But many people are now asking an important question:

What are the risks of losing weight too fast? And why are some people experiencing back pain after weight loss?

As a chiropractor and spinal health expert, I’ve started to see a pattern: patients who lose a lot of weight with these medications are coming into the clinic with new or worsened back pain, changes in posture, and a sense of core weakness.

So let’s take a closer look at what’s going on—and what you can do to stay strong and pain-free if you're using (or thinking about using) these medications.

What Are GLP-1 Medications?

GLP-1 receptor agonists (like Ozempic, Wegovy, and Mounjaro) work by:

• Suppressing appetite

• Slowing stomach emptying

• Helping the body regulate blood sugar

The result? Many people lose 10–20% of their body weight in just a few months.

That sounds like a win—and for many people, it is.

But the speed and scale of this weight loss can come with hidden consequences if not managed correctly.

GLP-1 Weight Loss Risks: It’s Not Just Fat You’re Losing

One of the lesser-known GLP-1 weight loss risks is muscle loss.

Research shows that up to 40% of the weight lost on these drugs can come from lean body mass—that includes muscle.

Why does that matter?

Because muscle is essential for spinal health. It stabilises your back, supports your posture, and protects you from injury. When you lose muscle, especially in your core and back, your spine can become more vulnerable.

This helps explain why some people experience back pain after weight loss—even though they’re healthier in other ways.

Why You Might Feel Back Pain After Weight Loss

Here are three common reasons people feel new or worsening back pain after losing weight:

1.Loss of Core Strength

Your abdominal and lower back muscles act like a natural corset for your spine. If you lose too much muscle without strengthening exercises, your spine has less support—and you may feel pain when bending, lifting, or even standing for long periods.

2.Postural Changes

When you lose belly fat or weight from your upper body, your centre of gravity changes. This can affect the natural curves of your spine and strain muscles and joints that were used to supporting a heavier frame.

3.Bone Density Concerns

Rapid weight loss—especially without exercise—can lead to bone thinning. This is especially true in the spine and hips, where less mechanical loading (from both body weight and muscle use) can lead to a loss of bone density over time.

The Good News: You Can Prevent These Problems

Here’s the part that too many people miss:

These issues are avoidable—but only if you take an active role in protecting your spine, muscles, and bones while you’re losing weight.

Here’s how:

✅Eat enough protein

Aim for at least 80–120g of protein per day (depending on your size and activity level) to support muscle retention.

✅Do resistance exercises

Simple bodyweight exercises like squats, wall sits, bridges, and planks can make a huge difference. Twice a week is a great start.

✅Stay mobile

Walking, climbing stairs, and using your body throughout the day helps maintain bone density and joint function.

✅Treat GLP-1 meds as a short-term tool

These drugs are not meant to be used forever. Use the momentum they give you to build new habits—not avoid them.

Final Thoughts

GLP-1 medications can be life-changing, but they’re not a shortcut to long-term health. If you're using these drugs, or thinking about it, take steps now to protect your spine, preserve muscle, and stay strong as you lose weight.

That way, you’ll be lighter—but not weaker. Healthier—but not more fragile. And you’ll be able to move freely and confidently in your new body.

If you're experiencing back pain after weight loss, or want guidance on how to support your spine during your weight loss journey, we’re here to help. Book a consultation at Your Spinal Health, and we’ll help you stay strong from the inside out.

Peter Bennett, DC
Chiropractor and Spinal Health Specialist
Your Spinal Health