CONSUMPTION of red meat and sugar worldwide must be halved by 2050 to avoid "potentially catastrophic" damage to the planet.

Humans should switch to a largely plant-based diet instead and more than double their intake of fruit and vegetables, nuts and legumes such as lentils and chickpeas, said scientists.

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The findings are published today in the Lancet, and are the result of work by the Eat-Lancet Commission bringing together 37 international experts.

The project, based on three years of research, provides the first scientific targets for a healthy diet for "sustainable food production".

The world's population is predicted to balloon to 10 billion by 2050, placing unprecedented pressures on the planet's resources.

The authors warn that "current diets are pushing the Earth beyond its planetary boundaries, while causing ill health".

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They estimate that 11 million premature deaths a year would be prevented if a radical shift away from animal products and highly processed foods could be achieved.

As a whole, consumers in North America currently eat 6.5 times the recommended amount of red meat.

The authors add that current food production is "exceeding planetary boundaries – driving climate change, biodiversity loss, pollution due to over-application of nitrogen and phosphorus fertilisers, and unsustainable changes in water and land use".

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Dr Walter Willett, a professor of nutrition at Harvard University who co-leads the Commission, said: “The world’s diets must change dramatically.

"More than 800 million people have insufficient food, while many more consume an unhealthy diet that contributes to premature death and disease.

"To be healthy, diets must have an appropriate calorie intake and consist of a variety of plant-based foods, low amounts of animal-based foods, unsaturated rather than saturated fats, and few refined grains, highly processed foods, and added sugars.

"The food group intake ranges that we suggest allow flexibility to accommodate various food types, agricultural systems, cultural traditions, and individual dietary preferences – including numerous omnivore, vegetarian, and vegan diets.”

Professor Tim Lang, professor of food policy at City, University of London, added: “The food we eat and how we produce it determines the health of people and the planet, and we are currently getting this seriously wrong."