Sophie Thelosen

Clinical Nutritionist | Mosman, Sydney, Australia Wide

Gut issues, food intolerances or ongoing fatigue that won't resolve?

Gut symptoms · SIBO · Food and supplement sensitivities · Histamine intolerance · Oxalate sensitivity · Chronic fatigue and low resilience · Post-viral illness (including Long COVID and POTS)

I'm a Clinical Nutritionist working with people whose symptoms are persistent, complex, or don't fit neatly into a single diagnosis. If you've already changed your diet, tried supplements, and still don't feel well, the next step isn't doing more, it's understanding what's actually driving your symptoms.

I practise as part of the integrative team at Mosman Integrative Medicine, and consult both in person and via telehealth across Australia.

Work With Me
Learn more

You might be in the right place if you:

  • Have ongoing gut symptoms that haven't settled despite dietary changes

  • Feel like you're "reacting to everything", foods, supplements, or both

  • Are living with chronic fatigue, low resilience, or post-viral illness

  • Have been told your tests are "normal" but still don't feel well

  • Want to understand why your symptoms are happening, not just manage them

Precision over protocols

Most people I see have already tried multiple diets, supplements, and approaches without lasting benefit. My work is different: I take a clinical, investigative approach to find what's relevant for your body, then help you simplify rather than add more.

Testing is used thoughtfully, never automatically. Treatment plans are individualised, realistic, and refined over time as your body responds. The goal is clarity and steady progress, not another rigid regime.

What working together looks like

1. Comprehensive initial consultation 

We map the full picture: your symptoms, health history, pathology and test results, and everything you've already tried.

2. An individualised plan 

I develop a nutrition-focused treatment plan tailored to your needs, tolerance, and capacity — with clear explanations at every step.

3. Ongoing refinement 

Complex issues improve gradually. Follow-up sessions let us interpret results, adjust, and keep your care responsive over time.

Testimonials

  • Sophie is a thoughtful and supportive practitioner who helps me manage a complex gut diagnosis with research-backed advice, creativity, and good humour. Her expertise and care are critical in helping me live a flourishing life

    — Matthew, Client

  • Sophie’s deep knowledge of nutritional science has helped me greatly in tackling some complex health issues. Her advice on personalised approaches to diet and supplementation has provided clarity amid the confusion of chronic illness. She’s also just very friendly and shows genuine care for my well-being. Highly recommended!

    —Ben, Client

  • Sophie’s approach to your care is wholistic and intuitive. She is dedicated to giving you some relief or helping you reach your health goals. I think of her as a super health sleuth. Highly recommend her to improve your life.

    – Sally, Client

Registered Clinical Nutritionist (ATMS) · Practising within an integrative medical team at Mosman Integrative Medicine · In-person and Telehealth on Thursdays & Fridays · Australia-wide

Ready to understand what's driving your symptoms?

If this approach feels like the right fit, you can book a consultation directly, or get in touch with any questions first.

My Articles

Blog
Why Am I Reacting to Everything? Making Sense of Food and Supplement Sensitivities
Why Am I Reacting to Everything? Making Sense of Food and Supplement Sensitivities

Feel like you react to every food and supplement? A Sydney clinical nutritionist explains what drives widespread sensitivities, and why more restriction backfires.

Read more →
Gut Microbiome Testing: What It Can (and Can’t) Tell You
Gut Microbiome Testing: What It Can (and Can’t) Tell You

Thinking about a gut microbiome test? A Sydney clinical nutritionist explains what these tests can and can’t tell you, and when they’re actually worth doing.

Read more →
SIBO Explained: Small Intestinal Bacterial Overgrowth, Its Symptoms, and Why It Keeps Coming Back
SIBO Explained: Small Intestinal Bacterial Overgrowth, Its Symptoms, and Why It Keeps Coming Back

Bloating soon after eating? A Sydney clinical nutritionist explains SIBO, its symptoms, why microbiome tests miss it, and why it keeps coming back.

Read more →
Histamine Intolerance: Why You Might Be Reacting to Healthy Foods
Histamine Intolerance: Why You Might Be Reacting to Healthy Foods

Reacting to healthy foods like wine, cheese or leftovers? A Sydney clinical nutritionist explains histamine intolerance: symptoms, causes and how it's managed.

Read more →
POTS and Dysautonomia: How Nutrition Can Support You Alongside Medical Care
POTS and Dysautonomia: How Nutrition Can Support You Alongside Medical Care

Racing heart and dizziness on standing? A Sydney clinical nutritionist explains POTS and dysautonomia, and how nutrition can support you alongside medical care.

Read more →
Post-Viral Fatigue and Long COVID: How Nutrition Can Support Recovery
Post-Viral Fatigue and Long COVID: How Nutrition Can Support Recovery

Still exhausted months after a virus? A Sydney clinical nutritionist explains post-viral fatigue and Long COVID, and how nutrition can gently support recovery.

Read more →
View All

Follow me on socials
Facebook
Instagram