Primary, Secondary and Tertiary Prevention.

I recall during my early years of general practice asking my mentor “What do we actually do?” The answer was a good one, “We intervene in our patients lives, a little bit in each consultation”.

A second experience was introducing to our General practice a program that was highly effective at reversing Prediabetes and T2 Diabetes. We have demonstrated over 150 patients normalising their HbA1c and coming off medication. Despite this unprecedented success the program was not embraced with any enthusiasm. I was perplexed to understand why.

I have just read Dr David Beaumont’s superb book “Positive Medicine”. I think I now can answer both queries. On page 91 he describes Primary, Secondary and Tertiary Prevention.


Primary prevention being the prevention of illness and promotion of health.


Secondary Prevention being spotting problems early, intervening early to prevent them developing and reversing the process.


Tertiary prevention being mitigating the effect of the illness and helping the patient to live with the condition.

In a wider context we also have secondary and tertiary level hospital care.

Working backwards I think secondary and tertiary level hospital care know exactly what their role is and do the job of treating severe and acute illness extremely well.

(Primary prevention is largely the role of Public Health and NGOs such as the Heart Foundation and again they do their role well)

The problem, as I see it, is with Secondary and Tertiary prevention. I believe there is a discrepancy between what General Practice actually does and what patients/clients expect of primary care. Primary care primarily does tertiary prevention with the prescription of medication to manage the symptoms of chronic disease. Primary care also does screening.

Most patients expect their General Practitioner to be involved in spotting problems early. Predicting and preventing problems and reversing them if they are detected. They want their GP to listen, spend time and take care. They want their GP to be interested in them as people and to be interested in their whanau and wairua.

For many reasons, including time pressure, practitioner burnout and a lack of training in Positive Medicine and Wellness clients are disappointed.

The solution is, in my opinion, to support GPs to do exactly what they do, manage chronic disease and help patients to live as well as possible with their conditions. Then add a new level of medicine focused on Secondary prevention. This new layer will focus on positive medicine and wellness, preventing illness when possible, reversing it when needed and supporting and empowering clients to adapt and self-manage life’s challenges. This is a wellness model of health. It is complementary to the existing and necessary illness model. This new layer will allow GPs to be clear about what they do and how they do it. They can state it clearly and define their niche. This will prevent the current level of customer dissatisfaction resulting from not having their needs met in Primary care.

I envision positive medicine clinics complementing but not competing with general practice. I envisage clients using both services as needed. I see no conflict of interest or competition as each clinic will have a different niche.

This would allow GPs to spend more time and focus on what they are trained to do.

This would allow clients to have their desire for holistic, preventative medicine met. The new clinic would be staffed by a multi-dimensional team including doctors trained in wellness medicine, nurses, health coaches, nutritionists, psychologists, physios and OTs. There would be referral and collaboration between these clinics and tertiary prevention services.


In this model all win, especially the clients.

My initial question

“what do I actually do as a GP” would be easily answered, “I provide support to help patients manage their chronic conditions.

My second question

“Why hasn’t diabetes reversal been embraced by general practice?”

Because it was outside the scope of general practice. It is not what they do. It is not tertiary prevention.




Glen Davies

Glen Davies

GP at Reversal NZ

Dr Glen Davies is a GP specialist with dual fellowships in both general practice and lifestyle medicine. He is a passionate advocate of lifestyle approaches to reversing chronic disease. Through his prescription of LCHF/ keto diets, he has helped over 100 patients reverse their prediabetes and type 2 diabetes.

Glen was recognised for his work in 2021 by being awarded the prestigious GP of the year title at the NZ primary care awards.

Becoming frustrated by failing to address prevention and by managing treatable conditions rather than aiming for cure, Glen “why” is now to make a difference as a healer and to contribute to the creation of healthier communities. He combines the power of Low Carb/Healthy Fat, Ketogenic Diets and fasting with a coach approach, to walk beside clients supporting them on their healing journey.

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