Speaking at last month's sustainable protein forum at Tai Tapu, south of Christchurch, Auckland University of Technology senior lecturer and registered dietitian Dr Caryn Zinn said more research was needed to establish the health benefits between plant proteins and red meat.
''The research looking at plant-based eating, or vegans versus omnivores, is not the kind of research that is showing us what we need to see.
''We need to do randomised-controlled trials and we need to have groups that eat whole, unprocessed foods, and the two groups need to compare meat eating and they need to compare vegans in that context.
''And it's only once that research has been done that we can compare the health benefits.''
Dr Zinn said there was a danger of ''a healthy user bias'' in making conclusions, as there could be other factors such as exercise and not smoking or consuming alcohol.
''If you have a positive health behaviour, such as a vegan, it typically comes with good health behaviours, so not only are you eating healthy, but you are physically active and you're less likely to smoke, so there are all sorts of behaviours these studies don't cater for.''
She said plant based eating was deficient in certain nutrients, such as vitamin B12 and omega 3 fats which could only be found in animal and fish products.
With so much information available, Dr Zinn acknowledged it could be confusing for parents to make healthy choices for their children.
But keeping it simple with whole, unprocessed foods was the best solution, she said.
This included red meat in a balanced diet which included plant proteins.
''One of the biggest issues is food literacy, and while we can argue the scientific principles at a higher level, it's left to the individual who is confounded and doesn't know what to do.
''I think people just need to think about the foods that we've evolved with, plants and animals.
Meeting the challenges of human obesity and climate change was no easy task, but she said removing meat entirely from our diet was not the answer.
''We would be doing our health a major disservice if we stopped eating meat altogether, but we need to look at the way we eat meat and the way we farm animals globally.
-By David Hill
