Our People

Dr Mandy Bergstrom – Chairperson

I am Mandy, a doctor based  in Ivercargil. I have a passion for preventative medicine, which involves addressing the risk factors that contribute significantly to our leading causes of death and disease (not just throwing pills at a patient once a disease has already occurred).

Diet is the number one risk factor for early deaths worldwide, yet it is often not sufficiently addressed in our hospitals, practices or even medical schools. We owe it to our patients to provide them with accurate and up-to-date knowledge to help prevent and potentially reverse chronic diseases, which is why I am promoting a whole-food, plant-based diet.

Peter Barclay – vice chairman

Peter is a former full-time journalist who spent most of his career in community journalism as a reporter, photographer, layout-sub and editor. In late 1999 he transferred those skills to the web when he began producing commercial websites with his wife Catherine.

For Peter and Catherine, life changed a lot when he had a stroke in May 2014.

“It certainly scared me and baffled Catherine because, after some health issues around the extended family, she thought our meals were healthy. How little we both knew.”

Together they embarked on a journey to understand the route cause to ill-health and discovered a whole range of issues that prominent scientists and medical professionals were calling lifestyle illnesses – issues that could be resolved by changing your diet and lifestyle.

That led them to a decision to create Whole Food Living magazine and to a meeting in Gisborne where Evidence Based Eating was formed.

Rajaraman Venkateswaran – treasurer

Rajaram is an IT professional who has been in the industry since 1983, having spent 14 years in India, 20 years in the UK and the rest here in NZ. His experience covers project management of the IT aspects of bank acquisitions & mergers, change management, ERP, LAN, building automation, etc.

He moved to NZ in 2018. He and his family were brought up as vegetarians and he switched to a plant based diet in 2017. He was the treasurer at the Northland Woodturners & Woodworkers club between 2019 and 2023.. His hobbies include wood turning, carving and playing the tenor saxophone.

Tania Archer – secretary

Growing up on a New Zealand dairy farm Tania was raised on a standard kiwi diet. She had a very active sport focused childhood which lead her to become a gym and aerobic instructor in her early 20’s.

Watching her mother struggle with her weight throughout her life coupled with her exercise driven background motivated Tania’s interest in nutrition and healthy living. She owned a café for 4 years with a focus on healthy options but only became educated in veganism and then WFPB (whole food plant based) at the beginning of lockdown 2020 with Netflix documentaries such as What the Health, Cowspiracy and The Game Changers.

Tania is a passionate advocate for plant based health and education on the prevention of chronic diseases. She holds a certificate in Plant Based Nutrition from eCornell University and is a founding member of Plant Centered Health New Plymouth, a Plant Pure Communities Pod group.


Grant Dixon

Grant is a film producer who in the past worked as a producer/director for the National Film Unit in Lower Hutt. More recently Grant worked as a Conferences Producer for EMA and an Event Manager for Massey University in Albany, Auckland.

Grant has made documentaries for TVNZ and TV3 and recently made the whole food plant-based feature length documentary; ‘The Big FAT Lie’ which currently is available for rent on iTunes and Vimeo On Demand. Grant holds a Master in Communications degree from Victoria University, and is actively involved in community issues in Hobsonville Point where he lives.

Grant co-founded Evidence Based Eating in 2019 following the NZ Lifestyle Medicine Conference in Gisborne.

Dr Thomas Joseph

Dr. Thomas Joseph, currently a GP at Invercargill’s He Puna Waiora Wellness Centre, regularly runs a three-day holistically-approached, lifestyle retreat with his wife at Camp Columba, in Gore.

Thomas was twenty-five, and living in his former home of Kerala, India, when he received a devastating diagnosis. Just months after he was married, he started experiencing stomach pain, nausea and what seemed like repeated bouts of gastroenteritis.

His first instinct was to attribute the symptoms to his hectic new work schedule and his associated poor diet of takeaways. However, when a bowel obstruction landed him in hospital and resulted in the loss of a significant portion of his intestine, he knew the situation was much more serious.

A subsequent diagnosis of Crohn’s Disease outlined a dismal future; the apparently incurable chronic inflammatory bowel disease would mean a lifetime battling painful symptoms that could be mitigated only with steroids. However, the ever-increasing doses of steroids prescribed to him, only exacerbated the symptoms, as did the advice from health professionals to eat more red meat and move away from fiber-rich, plant-based, foods.

It was not a future Thomas was prepared to accept, and so began his search for a better outcome and his discovery of the benefits of whole food plant-based eating.



Dr Mark Craig

Mark’s main passion in medicine is the prevention and reversal of our most common diseases in patients using the astonishing power of whole food plant-based nutrition and lifestyle changes.
After attending Edinburgh Medical School, Mark trained in surgery and then General Practice in the UK, having published several peer-reviewed medical papers in various specialities.

He moved with his family to Auckland in 2010 and is raising two plant based boys age 8 and 10. He enjoys the New Zealand outdoors and competes in endurance swim, bike and run events, representing New Zealand age group teams on several occasions.

Mark is also a founding member and former vice chairman of EBE. He regularly speaks at lifestyle and nutrition conferences and events.

Catherine Barclay

Like most of us, Catherine was brought up on the standard Kiwi diet. In the early days, there was lots of home baking, pavola and ham at Christmas and she just couldn’t resist brandy snaps – they were a favourite.

“When I think back on it now I just shake my head,” she says. “It wasn’t until I came across WFPB eating that I began to understand what healthy eating really meant and how important it is to all of us.”

Today, in association with her husband Peter, she helps run Whole Food Living magazine, a quarterly publication that explains what whole food eating is all about. She is also full-time employed as a service delivery manager with NZ Post.

She has an extensive background in web development and database management.

Dr Martyn Williamson

Martyn Williamson moved to New Zealand from the UK in 1986. He has spent the last 35 years in rural general practice, mixing this with a teaching and research role at Dunedin School of Medicine.

He has always been passionate about helping people thrive, and over the last 5 years has turned his focus on helping people prevent, reverse and cure their chronic illnesses.

He and his wife Liz were nominated ‘Plant Based Practitioners of the Year’ for 2019, and in 2020 they both obtained an international certification in Lifestyle Medicine.

Martyn is committed to raising awareness about the power of whole food plant-based nutrition to treat disease so that people have a choice to regain some control over their health.

Renee Walker – social media

“Renee Wallace is a published author and nutrition enthusiast based in South Otago, New Zealand. After facing a serious health issue, Renee became deeply intrigued by the idea of food as medicine, which led her to complete a qualification as a Food Matters Nutrition Coach.

As an aspiring marathon finisher and novice mountain biker, Renee is passionate about the benefits of an active lifestyle and healthy eating. Her personal journey has inspired her to help others discover the power of nutrition in achieving their own health goals.

Whether she is exploring the great outdoors, experimenting in the kitchen, or sharing her insights through her writing, Renee is dedicated to helping others discover the joys of a healthy, active lifestyle.”


Evidence Based Eating New Zealand Incorporated
is a registered charitable organisation. It is governed by its own constitution.

EBE  was incorporated on April 15, 2020.

To view the full document:

Our Mission

To raise awareness of Whole Food
Plant-Based nutritional benefits in New Zealand by educating and inspiring the general public, health professionals, private organisations and government institutions using evidence-based research.


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Disclaimer: The medical and/or nutritional information on this website is for educational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Please seek medical advice before using diet to treat disease.