AUSTRALIAN doctors are being assured their patients will benefit if they adopt a diet that's free of meat.

An Australian-first scientific research review, published today in the Medical Journal of Australia (MJA), has found vegetarians receive more health benefits than risks from their plant-based diet.

The MJA supplement examined deficiencies traditionally thought to affect those who have adopted a vegetarian diet and found they are receiving adequate levels of protein, iron and zinc.

Nutritionist Dr Rosemary Stanton, who has written an accompanying editorial to the research papers, says the scientific evidence shows a well-planned, plant-based diet can meet the nutritional needs of adults and children.

"The evidence is quite good that people who follow a vegetarian diet are likely to have less heart disease, less colorectal cancer, less type-2 diabetes and they're less likely to be obese," she said.

While those who don't eat fish may be receiving less Omega-3 fatty acids than considered desirable, the study also found vegetarians don't exhibit signs of a clinical deficiency.

Deficiencies in vitamin B12 were noted in vegans; people who shun any animal-based product including milk and eggs.

B12 is required to help make red blood cells and to keep nerves functioning and the study recommended vegans receive supplements either through eating B12-fortified foods or by taking a daily supplement.

Dr Stanton says the study was also prompted by the increase in the number of people who are looking to reduce their intake of meat for both health and sustainability.

"The question they've been asking, which this supplement aims to answer, is 'is there a problem if I don't have meat every night?' and the answer is almost certainly no, but it doesn't mean that you just have a bucket of chips," she said.

Originally published as Doctors reassured about vegetarian diets