British Prime Minister Boris Johnson said he would find it very hard to go vegan because it would mean giving up cheese. All across the world, however, there are millions of people with no such qualms.

There’s been a huge shift towards veganism in the last five years, predominantly among young people but also across all ages.

The increase has been driven by several factors from concerns about the safety of eating meat products, to ethical concerns about animal welfare and more recently, a growing awareness that meat production takes up a disproportionate amount of land compared to arable crops and so has become a major contributor to global warming.

There’s no doubt that a vegan diet can be perfectly healthy, but as with any diet, it’s important to ensure you are getting all the nutrients your body needs. It’s all about balance. And that is where some people may be selling themselves short according to doctors and nutritionists.

Dr Eva Orsmond runs several weight loss clinics and has appeared on mainstream TV shows in Ireland. She has also released her latest book ‘Reverse Your Diabetes’ which relates how she helped patients reverse type 2 diabetes thanks to changes to their diets, supplements and hard work.

Dr Orsmond says that while a balanced vegan diet can be very healthy, she is worried that a lot of people decide to go vegan, often for the best of reasons, without considering how they will achieve a healthy, balanced diet once they remove meat and dairy products.

And it’s not as if veganism just means not eating meat and dairy, there’s a whole host of foods that use animal products without us even knowing it. It means that vegan food producers need to find alternatives when making ready meals, and that can cause a lot of problems.

Dr Orsmond says it means a lot of processed vegan food can be high in sugar to replace the taste that is lost by the removal of animal based fat.

“So often those vegan processed ready-made foods are usually the worst foods you can buy.”

It means people need to read up on exactly what their body needs when they go vegan for the first time. Of course, this could be said about meat eaters as well, and may even apply more so to them. But vegans run the risk of assuming that if it’s vegan, it must be healthy and this can lull them into a false sense of security.

Orsmond said: “Really if you want to be vegan, you need go somewhere and study properly and know your stuff. If you were doing a vegan diet properly, most probably it could be better and healthier than ordinary people who just put all sorts of processed grains and bread in their mouth.

“But I think we need to be careful not to start making it look like the vegan diet is super healthy.”

She also raised concerns over the lack of knowledge many people had about the vitamins and minerals that they could miss out on if they do not prepare a balanced vegan diet.

She said: “Then you need to think about B12, you need to think about iron and about Omega 3 fatty acids.

“You need supplements, you need the right supplements because where are you going to get your B12?

“Women menstruating are risking iron deficiency.

“There was one girl in her late twenties who has been basically missing her period for a year and she had been vegan for five years.

“Then we managed to convince her to start eating meat and her period came back in a few months.

“This was just a little while ago. We don’t have a huge amount of these cases but basically (with this case) there was a whole better energy and everything else.

“They usually lack something. Often people who say they are vegan don’t know how to eat vegetables, and they don’t know (that with) some of the vegetables, iron doesn’t get absorbed well even though they are in the vegetables.”

Dr Orsmond said she would not like to see any of her family members become vegan as humans were ‘not designed’ for the diet. She said: “I would be really concerned. We weren’t designed to be vegan. That’s not how our body works.

“I’m not eating a huge amount of red meat myself but I like it and I have absolutely nothing against people who get their protein from red meat.

“I’m not against dairy, I just don’t think people should be drinking milk because of other calories but if you come to my house you will find dairygold butter and I just would not be able to live without cheese.”

Doctors and nutritionists say it is possible to eat a healthy and fully balanced diet as a vegan if the right approach is taken. The UK National Health Service offers the following bullet points summarising the right approach.

Eat healthily as a vegan

• eat at least 5 portions of a variety of fruit and vegetables every day
• base meals on potatoes, bread, rice, pasta or other starchy carbohydrates (choose wholegrain where possible)
• have some dairy alternatives, such as soya drinks and yoghurts (choose lower-fat and lower-sugar options)
• eat some beans, pulses and other proteins
• choose unsaturated oils and spreads, and eat in small amounts
• drink plenty of fluids (the government recommends 6 to 8 cups or glasses a day)

This always begs the question, how much in a cup, and is it different in different countries. This chart from (allrecipes.co.uk) should help.

Metric UK (Imperial) US cups

250ml 8 fl oz 1 cup
180ml 6 fl oz 3/4 cup
150ml 5 fl oz 2/3 cup
120ml 4 fl oz 1/2 cup

Orsmond says vegan is not simply another word for healthy, as processed vegan foods can be just as high in sugar as non-vegan so check the labels and choose carefully. If you feel you have no choice but to have vegan foods and drinks that are high in fat, salt or sugar, try to keep the portions small and have them as little as possible.

In recent years, some scientists have also become concerned about the lack choline in many people’s diets and warn that vegans could be badly affected if they don’t take it into account as part of their diet.

Choline is important for several functions including memory, mood, muscle control and may play a part in protecting against mental decline as we get older.

British nutritional consultant Dr Emma Derbyshire says many people do not meet daily recommendations and the increasing rise of plant-based diets could make the problem worse.

Writing in the British Medical Journal, she said: “Physiologically, choline is critical for a number of functions across the life cycle, with choline deficiency being linked to liver disease, offspring cognitive function and potential neurological disorders.

Dr Derbyshire said that animal foods contain more choline per unit weight than plant sources. In general, beef, eggs, fish, chicken, nuts, milk and certain plant foods such as cruciferous broccoli provide some dietary choline.

“The mounting evidence of choline’s importance makes it essential that it does not continue to be overlooked. This is now more important than ever given that accelerated food trends towards plant-based diets/ veganism could have further ramifications on choline intake/status.”

There is a strong consensus among medical experts and researchers across the world that while a vegan diet can be healthy, and in some cases healthier than a meat-based diet, it must be done properly to ensure that all the essential nutrients found in meat-based products are provided, either from plant-based alternatives or health supplements.

The idea that vegan is more natural and so automatically better is as potentially dangerous as the opposite argument that humans are natural carnivores and can only thrive on a meat-based diet.

What’s important is that any diet, whether vegetarian, vegan or meat-based is only healthy if it provides all the necessary nutrients.