Veganism is having a moment. After years in the wilderness as a fringe movement, it has exploded into the mainstream. Driven by concerns about climate change and sustainability, it is now part of our national conversation.
Veganism was 'invented' in the UK in 1944, and its founding body, the Vegan Society, defines it as "a way of living which seeks to exclude, as far as is possible and practicable, all forms of exploitation of, and cruelty to, animals for food, clothing or any other purpose".
One of the central tenets is a wholly plant-based diet (a vegetarian diet by definition excludes meat and may include eggs, dairy etc) - and this is the part that has been swept up into the zeitgeist.
Veganuary - a non-profit movement that encourages people to try living vegan by eating plant-based foods for January - expect 350,000 people to have registered by the end of the month, up from 250,000 in January last year.
Of those, over 5,000 were from Ireland and as of today, just over a week into the challenge, 5,433 Irish people have signed up for Veganuary 2020. The group estimates that the amount of people actually participating is up to 10 times the registered number, so we are talking pretty significant volumes of people.
And they follow in the footsteps of the bold and the beautiful. Michelle Pfeiffer has spoken of going vegan for health reasons and for its anti-ageing benefits. Other celebrity vegans include Ariana Grande, Ellen DeGeneres, Joaquin Phoenix, Bill Clinton and Jessica Chastain. There has been much intrigue in the world press about whether Meghan Markle was or wasn't 'plant-based' based on an interview she did in 2016 when she declared that she tried to keep it vegan during the week, with more flexibility at the weekends. Which brings us to another incarnation of the trend - the flexitarian diet, where you are mostly plant-based but can eat meat 'from time to time'.
But what is the actual impact of a vegan diet on our health? Is it really a healthier, more sustainable way of eating?
"Vegan diets can be very healthy, but it depends on how well balanced the diet is," according to dietitian Maeve Hanan of DieteticallySpeaking.com. "For example, an unbalanced vegan diet can lead to anaemia due to low iron or vitamin B12 levels, weakened bones due to low calcium intake or thyroid issues related to a low intake of iodine. These issues can also occur for omnivores too of course, but there's a lower risk as red meat is high in iron and vitamin B12, and milk and yoghurt are high in calcium, iodine and vitamin B12."
But seriously. Can we really replace meat?
"Although meat is a nutritious food, we don't need it in our diet as there are plant-based alternatives to all of the main nutrients found in meat. More products are also emerging which more closely mimic the nutritional profile of meat. But it is more difficult to replicate the nutritional benefits of oily fish, and the specific type of omega-3 it contains. From a health point of view, most Irish people would benefit from reducing their intake of red meat to three portions per week maximum, and limiting their intake of processed meat like sausages, ham and rashers to occasional. There are many health benefits related to following a plant-based diet, but this doesn't need to be a plant-only diet if a vegan diet doesn't work for you."
A nutritionally complete diet without animal products sounds like a lot of work. Is it?
"It can take some planning and learning in order to achieve a balanced vegan diet" Maeve agrees. "This includes consuming a variety of plant-based protein sources (like beans, lentils, chickpeas, quinoa, nuts, seeds, soya protein etc), a variety of fruit and vegetables, vegan calcium sources (such as calcium-fortified soya drinks, dried figs, almonds, green leafy vegetables, tofu, sesame seeds), and vegan sources of iron (such as fortified cereals, beans, green leafy vegetables and yeast extract). Most vegans in Ireland are likely to need supplements, depending on their dietary intake, such as: vitamin D, vitamin B12, iodine and omega-3.
"Some groups are also more vulnerable to nutritional deficiencies on a vegan diet, such as pregnant women, older adults, those who are unwell or malnourished, babies and young children - so these groups may need extra support related to their diet and supplements from a dietitian."
Paediatric dietitian Caroline O'Connor of Solid Start works with parents who want to introduce their children to a vegan diet. Alongside the aforementioned possible deficiencies, she points out that: "Babies and children aren't mini-adults. Their need for calories relative to their tummy size is way higher than ours. And because vegan diets are high in fibre, kids can fill up quickly and miss out on much-needed calories. This is why careful planning is vital."
Joana Caldeira Fernandes da Silva is a dietitian with safefood, the all-Ireland body tasked with promoting awareness of nutrition and food safety, and mother to three teenagers.
"One of my daughters eats a traditional diet, my other daughter became vegetarian over the summer, and my son, who has been a vegetarian from the age of 12 is now following a vegan diet.
"Some products are quite expensive and sometimes the plant-based replacements of some of our staple foods use products like coconut oil so would be high in saturated fat and should be limited. He takes a Vitamin B12 supplement every day. And as important as the B12 is to ensure that he gets his information on vegan diets from reputable sources and not from an Instagram post!"
A number of so-called health gurus and clean-eating advocates on Instagram have turned out to have been suffering from eating disorders. What about those vulnerable to disordered eating? With the rise in orthorexia and an increased understanding of the dangers of extreme diets, could this be another path to an eating disorder for some?
"Vegan and vegetarian diets are sometimes used to mask an eating disorder, especially among teenagers, as it can be a socially acceptable way of cutting out food groups and reducing calorie intake," Maeve Hanan agrees. "The restrictive nature of cutting out food groups may also trigger disordered eating for some people. Of course many people follow a vegan diet and have a very healthy relationship with food, it really depends on the individual and their motivations for going vegan." If your motivation is concern for the environment, is veganism the way to go?
"A vegan diet can often be a more sustainable diet" says dietitian Orla Walsh. "This is because of the removal of dairy and beef, in particular. However, if those foods are removed and replaced with less environmentally friendly foods, the benefits with regards to the planet will be minimised.
"It's important to focus on wholefoods rather than processed foods and where possible local, seasonal foods. For example, one of the third biggest contributors to greenhouse gas emissions from the western diet include soft drinks and fruit juice, which are appropriate foods to choose on a vegan diet."
All this considered, if you do decide to embrace veganism, what changes can you expect? "A change in bowel habit is common due to the sudden increase in fibre," according to Maeve Hanan. "In some cases the bowels will improve and become more regular, whereas others experience bloating, pain, gas and diarrhoea. Most of us in Ireland don't eat enough fibre, so increasing our intake is generally a great thing to do, but it's best to do this gradually and to stay hydrated to reduce the risk of unpleasant gut issues."