According to a Report Buyer from 2017, 6% of consumers in the United States at the time claimed to be vegan, a significant jump from the 1% rate reported in 2014. An earlier study from 2010 estimated that there were 1.5 billion people following a vegetarian diet worldwide. There are many reasons that lead individuals to adopt a vegetarian diet including health-related issues, compassion for animals, concerns with planetary health and sustainability, and religion-related reasons, among others.
In the last years, the many individuals who have chosen to adopt a vegetarian diet no longer have difficulties in finding replacements for animal-based products such as milk, cheese, and eggs. In fact, the sales for substitute products have skyrocketed in the last years showing a growth rate 2.5 times higher than the total food sales. A study from 2021 reveals that the sales of substitute products grew 27%, going from US$ 5.5 billion to US$ 7 billion between 2019 and 2020 in the United States. However, there is still a lot of misinformation and misconceptions linked to the vegetarian diet, which is still not fully accepted as a healthy choice by many professionals in the health-care community.
To fix misconceptions, demystify the vegetarian plate and educate the medical community about the vegetarian diet, the International Vegetarian Union, an institution that is more than 100 years old with representatives worldwide, just launched the Guide to Vegan Nutrition for Adults, a 500-page comprehensive document about the vegetarian diet that is based on sound information backed by more than 700 peer-reviewed studies. "Our intention with this guide is to educate the health-care community about the benefits of a vegetarian diet by informing how each essential nutrient works and by correcting misconceptions, so doctors and dietitians will be better prepared to support the dietary choices of their patients," says Dr Eric Slywitch, the main author of the Guide.
The Guide cites peer-reviewed studies that have demonstrated how the vegetarian diet may be used as a treatment for specific conditions or a way to prevent diseases such as diabetes, cardiovascular disease, cancer, and obesity. On supplementation, the Guide corrects the long-time misconception that vegetarians need to add supplements to their diet whereas those following an omnivorous diet do not. The truth is that studies comparing diets do not take into consideration that farmed animals receive loads of supplements that end up on the plate of consumers of meat and animal products.
In fact, the only supplementation that those on a well-balanced vegetarian diet need to take is vitamin B12, and when it comes to B12 deficiency vegetarians are not alone. Studies have shown that 40% of the population worldwide have insufficient levels of B12. The Guide has more than 40 pages dedicated to this vitamin that explain its metabolism, how it is absorbed, the recommended levels of B12, how to treat B12 deficiency, and how to keep adequate levels of this vitamin.
Another misconception related to the vegetarian diet that is clarified in the Guide relates to phytoestrogen, which is found in soy, a staple food to many vegetarians. Because phytoestrogens share structural similarities with estradiol (17-β-estradiol), a number of studies have investigated whether a high intake of soy-based foods could affect the balance of sex and thyroid hormones. Some studies have also investigated whether phytoestrogens could be associated with a higher risk of developing estrogen-depending breast cancer. In 2016 and again in 2019 two meta-analyses showed that intake of soy-based food is in fact associated with a reduced risk of breast cancer and improved survival in those with the disease. Even though the American Cancer Society has encouraged the consumption of soy by breast cancer survivors since 2012, many doctors still tell their patients to avoid high intake of soy-based foods.
The Guide provides detailed information on all major nutrients required for the proper function of the human body, including vitamins, proteins, calcium, iron, zinc, iodine, and omega-3, to mention a few. It tells how the nutrient is absorbed, what the recommended levels are, what source foods are rich in the nutrient, what symptoms are associated with its deficiency, and the benefits associated with its intake.
The Guide to Vegan Nutrition for Adults is the first of its kind. After the first section that starts by explaining what exactly vegetarianism is, the following sections elucidate about supplementation, the nutritional adequacy of a vegetarian diet, macro and micronutrients, and antinutritional factors. Besides the PDF document, the Guide also directs the reader to classes available on YouTube taught by the Guide's main author Dr Eric Slywitch.
Lastly, the Guide provides a 30-day vegetarian menu that includes dishes from all over the world and recipes on how to prepare the food. The Guide is available for free in PDF format at the International Vegetarian Union's website and may be used for consultation by doctors and healthcare professionals to better understand how the vegetarian diet can help their patients, and by anyone interested in having only good food on their plate.