The term vegan diet describes a consumer behavior that is limited to the use of purely plant-based foods or products thereby abstaining from the consumption of foods with ingredients of animal origin. 
As public awareness for sustainability defects in animal agriculture have been on the rise in the recent 10-20 years, these issues provide motivation in many respects for people to move towards veganism. In Germany, 61% of vegans state animal protection as their key motive, while 8% primarily seek a healthier diet. Vegans decide to boycott all animal products because animal cruelty or the killing of animals is inherent to meat, egg, dairy and honey production, even when those are produced organically. Furthermore the comparably smaller negative ecological consequences of plant-based products are often highlighted, e.g. regarding greenhouse gas emissions, soil degradation, deforestation or the loss of biodivesity caused by animal feed production in non-European countries. These arguments are elaborated on in numerous studies. According to a study, a vegan diet can reduce land use by 76%, greenhouse gas emissions by 49% and eutrophication by about 49%. If agricultural production reduced animal farming along with animal feed production, the demand of a significantly larger group of people could be met while using the same agricultural area. Furthermore a carefully executed transition to a vegan diet would bring along significant benefits for human health. A perpetuating increase of vegan food consumption has the potential to contribute to a major change in agriculture, leading to less ecological and health-related costs both in Germany and worldwide.
notable increase of products and brands (›Impossible Burger‹, ›Oatly‹, ›Alpro‹), cookbooks (›Vegan for fun‹), events and festivals (vegan summer festival Berlin, 65,000 guests in 2018), trade fairs (VeggieWorld 20,000 guests, medical convention VegMed)
The earliest historically documented practitioners of a vegetarian diet lived in the 6th century BCE and were members of the Orphics, a religious community in ancient Greece. They avoided meat, eggs and wool based on their belief that human and nonhuman animal souls would be reborn. Simultaneously Jainism developed in India which prohibits causing harm against any being, including animals and plants, thus forbidding meat consumption. During industrialization of the 19th century meatless diets once more attracted great attention with the establishment of animal protection organizations and vegetarian associations. The Vegetarian Society was founded in Great Britain in 1847, with its 1944 spin-off, the Vegan Society. In Germany the Vegetarier-Union Deutschlands was founded in 1946. Nowadays it is known as ProVeg and teams up with other organizations such as Albert-Schweitzer-Stiftung für unsere Mitwelt in their focus on the promotion of vegan diets.
The number of vegans in Germany in 2016/17 is estimated to be in the range of 950,000  and 1.3 million people . In comparison, the Nationale Verzehrsstudie II determined just 80,000 vegans in 2008. Due to the rising demand for vegan products during the recent decade the commercial range diversified and now offers a wide range of processed vegan foods, including sausage and cheese alternatives. By now these are no longer limited to health food stores, but are available in almost any conventional supermarket. The market share of newly introduced German food and beverage products which are labelled as ›vegan‹ (13%) has overtaken the share of those labelled as ›vegetarian‹ (7%). Especially in metropolitan areas the number of fully or semi-vegan restaurants, cafes or bistrots that offer vegan dishes is continuously increasing.
If unbalanced, a vegan diet could potentially lead consumers to deficiencies in specific nutrients. Furthermore not all vegan products offered by grocery stores automatically classify as more sustainable or healthy, this for example is not the case with highly processed products.
A vegan diet describes a consumer behavior that is limited to the use and consumption of purely plant-based products thereby consciously excluding the consumption of foods with ingredients of animal origin. A vegan diet contains high potential for environmental relief and – due to increasing product ranges – it will inspire additional individuals to transition to a consistent vegan diet, or convince even more people of a largely vegan diet. By means of this paradigm shift this niche promises high transformative potential.
 In a broader sense, the descriptor vegan as a product property also applies to clothing, cosmetics and further daily consumer goods. Especially synthetic leather and microfiber products are preferred to leather products made from animal skin. Wool, fur, down, bristles and animal tested cosmetics are renounced. This conscious renunciation can influence the attitude towards other ethical questions in life, for example the rise in criticism of zoos, vivariums, animal-related sport, circuses etc. due to possible animal exploitation. (Albert-Schweitzer-Stiftung (2016): Warum vegan? Gründe und Gegenargumente, Web, 02.01.2019. albert-schweitzer-stiftung.de/aktuell/warum-vegan)
 Skopos (2016): 1,3 Millionen Deutsche leben vegan. Web, 02.01.2019. www.skopos.de/news/13-millionen-deutsche-leben-vegan.html
 For clarification: Objects of criticism are, for example, the fact that dairy cows are forcefully impregnated and then slaughtered when their milk rate drops; that their male children are slaughtered at early age as calves; that in the breeding of laying hens it is common practice to suffocate male chicks or to mangle them in shredding machines at full consciousness in order to increase financial profits.
 Springmann et al. (2016): Mitigation potential and global health impacts from emissions pricing of food commodities. Nat. Clim. Change 7, S. 69–74doi:10.1038/nclimate3155
 Poore, J. und Nemecek, T. (2018): Reducing food’s environmental impacts through producers and consumers. Science 360 (6392) 987-992, 01 Jun 2018, Web, 02.01.2019. 10.1126/science.aaq0216 ; The Guardian (2018): Avoiding meat and dairy is ‘single biggest way’ to reduce your impact on Earth. Web, 02.01.2019. www.theguardian.com/environment/2018/may/31/avoiding-meat-and-dairy-is-single-biggest-way-to-reduce-your-impact-on-earth
 Springmann et al. (2015): Analysis and valuation of the health and climate change cobenefits of dietary change. PNAS April 12, 2016 113 (15) S. 4146-4151. https://doi.org/10.1073/pnas.1523119113
 ProVeg Deutschland(2019a): Geschichte des Vegetariusmus und Veganismus. Web, 02.01.2019. vebu.de/veggie-fakten/geschichte-des-vegetarismus-und-veganismus/
 ProVeg (2019a)
 Statista (2017): Personen in Deutschland, die sich selbst als Veganer einordnen oder als Leute, die weitgehend auf tierische Produkte verzichten, in den Jahren 2015 bis 2019. Web, 09.04.2020. de.statista.com/statistik/daten/studie/445155/umfrage/umfrage-in-deutschland-zur-anzahl-der-veganer/
 Skopos (2016)
 BMEL (2008): Nationale Verzehrsstudie II: Wie sich Verbraucher in Deutschland ernähren, Web, 02.01.2019. www.bmel.de/DE/Ernaehrung/GesundeErnaehrung/_Texte/NationaleVerzehrsstudie_Zusammenfassung.html
 Deutsche Gesellschaft für Ernährung (DGE) (2016): Vegane Ernährung. Position der Deutschen Gesellschaft für Ernährung e.V. (DGE). Ernährungs Umschau 63(04), S. 92–102
 MINTEL (2017): Global new products database. Web, 02.01.2019. de.mintel.com/pressestelle/deutschland-die-nr-1-bei-veganen-lebensmitteleinfuehrungen
 Acxiom (2016): Vegetarier: weiblich, urban, markeninteressiert. Web, 02.01.2019. www.acxiom.de/vegetarier-weiblich-urban-markeninteressiert/; Vebu (2019b): Vegan-Trend. Fakten zum veggie-boom. Web, 02.01.2019. vebu.de/veggie-fakten/entwicklung-in-zahlen/vegan-trend-fakten-zum-veggie-boom/