A grandpa has revealed why he has stayed vegan for more than 30 years - and it isn’t for animals.

John Collings, from Rutherglen, has enjoyed a plant based diet for over three decades to help save the environment.

The 76-year-old was sceptical when his teen son first suggested the idea, and went to the library to investigate as he did not have access to the internet then.

He was surprised to find out being vegan would mean his food production would use 75 percent less land, 54 percent less water and 66 percent less biodiversity loss.

Now for Veganuary, John told the Glasgow Times how he has never looked back after making the pledge on his 43rd birthday in 1990.

Glasgow Times: John is passionate about the environment John is passionate about the environment (Image: Colin Mearns)

He said: “I did not become vegan because of any concern about animals but because of the environment.

“I am very happy it can help the animals, but it wasn’t my main motivator when I started out.

“My son was becoming plant based and I was worried so I researched it, I was really surprised to see how beneficial it would be for the planet.

“I have a 16-year-old grandson and I want the world to still be there for him, the environment matters so much.”

John told the Glasgow Times how things have changed for vegan choices in mainstream shops and restaurants.

He is glad to see a surge in popularity for plant based diets and hopes more awareness around climate change could be driving it.

It comes after research published last year found that vegans had an environmental footprint roughly one-third the size of high meat eaters.

Professor Peter Scarborough, from the Nuffield Department of Primary Care Health Sciences, led the research which studied data from over 55,000 individuals, linking their dietary preferences with information on the environmental impacts of the foods they consumed.

The results also found that even eating less meat still contributed to a reduction in environmental impact by 30% compared to high meat eaters.

John said: “You’re never too old to start being vegan, I was 43 when I started but quickly adjusted.

“Since I have been doing it for so long I have watched how much things have changed.

“You couldn’t go into the shops and pick things up like you can now, that has only come around in recent years.

“Luckily my family was very supportive and we focused on plant based home cooked meals.

“Chinese and Indian restaurants have always been good for vegan alternatives but British restaurants can often struggle.

“I am glad to see it becoming more popular, hopefully people being more environmentally conscious is part of it.”