Tofu is worse for the environment than meat, according to UK farmers.

This is despite studies showing that following a vegan diet could be the ‘single biggest way’ to reduce your environmental impact

At a conference in London, the National Farmers Union presented academics and scientists who argued that a meat-free diet could be unhealthy, create more emissions and damage the ecosystem.

One of the speakers at the conference, talked about unpublished work that suggests tofu, a protein substitute made from soy milk, has a worse impact on global warming than lamb, pork and chicken.

Canterbury-based nutrition scientist Dr Graeme Coles told Kerre McIvor that the farmers are right in this instance.

He says the most important nutrient every day is the nine amino acids that we cannot make them ourselves.

"There is no plant-product that supplies that range of essential amino acids with as little byproducts of non-essential amino acids that comes from either meat or dairy."

Dr Coles says that consuming a meat or dairy-rich diet to meet the amino acids minimum, we secrete fewer wasted amino acid residues than if we were eating plant-based diet.

He says that the nitrogen from human excretion is a huge contributor to greenhouse gases and pollution.

"There's seven billion of us, and if we were eating 30 grams of nitrogen a day more than if we were on a strictly animal based diet, that's an awful lot of nitrogen pollution to deal with.

"It either goes into the atmosphere, or goes into groundwater."

Dr Coles says that the recommendation is to have a mixed-diet of animal-based products and vegetables and fruit.