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We recently caught up with Kirsty Cullen who is the Chief Executive Officer at The Optimum Health Clinic (OHC).

OHC is an award-winning clinic which offers an integrative, personalised and evidence-based approach to achieving optimum health. Combining nutritional therapy with therapeutic coaching, the OHC team has worked with 10,000+ people in 50+ countries in the last 20 years.

OHC has specialised in complex fatigue-related illness since its inception, and over the years has developed highly regarded frameworks and protocols which offer support to clients across a broad range of health concerns such as stress, sleep issues, trauma, digestive issues and nervous system dysregulation.
OHC recently entered into an exciting new chapter with the development and launch of Therapeutic Nutrition training program which won ‘BEST EDUCATION SERIES’ in the 2023 IHCAN awards.

Why Nutri Advanced?

Kirsty, shared her thoughts on why OHC enjoy working with Nutri Advanced products and also picked out her top three recommendations for stress support.

"The nutrition team at OHC are passionate about clinical excellence and continued evidence-based protocol evolution, and this has been a philosophy central to our practice over the last 20 years. During this time, Nutri Advanced products have been a constant feature in our nutrition protocols. We value companies who share our passion for offering clinical recommendations grounded in the evidence base and enjoy working with like-minded professionals who strive to incorporate the latest research findings into the development of clinical new tools and supplements. We have established a valued professional relationship with Nutri Advanced over the years due to our shared ethos."

The OHC practitioner team's favourite Nutri Advanced products:

Magnesium Glycinate

Sub-optimal magnesium levels are not an uncommon clinical finding in our clients and so we really appreciate a highly absorbable magnesium supplement. Given the complexity of fatigue cases, we typically find that our clients can be sensitive to new supplements, particularly through the gastrointestinal system. The magnesium bisglycinate formulation in this product appears to be very gentle on the gut, which is highly beneficial. Members of our nutrition team here at OHC describe Nutri Advanced’s Magnesium Glycinate as their ‘first go to’ when it comes to magnesium supplementation. This is particularly true when it comes to supporting clients around stress and sleep, and of course glycine is suggested in research to have a calming effect on the brain.


Chronic and long-lasting fatigue is often seen hand-in-hand with stress in clinical practice. It is our experience that a maladaptive stress response can perpetuate the fatigue cycle and place pressure on adrenal function. Calming the nervous system is therefore often a central factor in our clinical considerations. For many years we worked with single adaptogenic herbs and nutrients, including ashwagandha, siberian ginseng, lemon balm and reishi, in order to support our clients and their stress response. Consequently, we were delighted to see that Resilience beautifully combines so many of these elements mindfully into one product. This has become a favourite in my own clinical tool kit.

MegaMag Calmeze®

Another favourite in the OHC toolkit is Megamag Calmeze®. Within our client group, the focus is commonly on optimising mitochondrial function. This product combines magnesium and key B vitamins - which are nutrients shown to be central to the function of the Krebs Cycle and energy production - whilst also including thoughtful elements aimed at supporting the stress response. Our practitioner team really values the dual focus of this product and our clients really benefit from the easy powdered format, which allows them to slowly increase their dosage at their own pace.

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Nutri Advanced has a thorough research process and for any references included, each source is scrutinised beforehand. We aim to use the highest value source where possible, referencing peer-reviewed journals and official guidelines in the first instance before alternatives. You can learn more about how we ensure our content is accurate at time of publication on our editorial policy.