A flexitarian diet, also known as a semi-vegetarian diet, focuses on eating mostly plant-based foods and having less meat and other animal products. People who choose this diet often eat less red meat and poultry, and they eat more fruits, vegetables, and grains. They may choose this diet for health, environmental, ethical, or economic reasons.

Definitions

Flexitarianism is a way of eating that focuses mainly on plant-based foods, such as fruits, vegetables, and grains, while allowing meat or other animal products to be eaten sometimes. The meaning of flexitarianism can differ in various countries because people eat differently in different places. Studies from around the world show that flexitarianism is a general term used to describe eating less meat without strict rules. According to the Dutch environmental group Natuur & Milieu, a flexitarian does not eat meat, fish, or lunch meat for at least one day each week. The Dutch research group I&O Research describes someone as flexitarian if they avoid meat one or more days a week. The Dutch food health authority, Voedingscentrum, says flexitarians avoid meat (but may eat fish) on three or more days a week, either separately or with a hot meal.

The term "flexitarian" is relatively new and became more widely used in the 2010s in both scientific and public discussions. The word "flexitarian" was added to the Merriam-Webster's Collegiate Dictionary in 2012. In 2003, the American Dialect Society named "flexitarian" the most useful word of that year.

The term "flexitarian" can also be used more broadly to describe eating less of any animal products without completely stopping. For example, someone might avoid eating meat from certain animals but still eat meat from others. Vegetarianism is the practice of not eating meat or any other animal tissue. Other new terms that describe eating less animal products include demi-vegetarianism, reducetarianism, and semi-veganism. Because definitions of flexitarianism vary widely in different studies, researchers often look at general trends in meat reduction rather than strict rules.

Prevalence and trends

Research and surveys show that eating less meat is becoming more common in many countries, with the term "flexitarianism" used to describe this trend. A study from 2015 and 2016 found that more than half (55%) of Dutch people were flexitarians. Research by Wageningen University & Research shows that the number of Dutch people who call themselves flexitarians rose from 14% in 2011 to 43% in 2019. However, the number of days per week that self-described flexitarians ate meat increased from 2.9 days to 3.7 days during this time. Researchers believe this change may be partly because the term "flexitarian" is used in different ways by people in the Netherlands. Estimates of flexitarianism vary across studies because people often define the term differently.

Other studies found that daily meat consumption by Dutch people dropped significantly between 2010 and 2012. A 2012 study by the Dutch research agency Motivaction reported that 35% of Dutch people chose to reduce their meat eating intentionally. About 14.8% of the population ate meat no more than one or two days a week. In Flanders, 1 in 6 people in 2013 avoided meat on one or more days each week.

A 2018 study estimated that 12% of UK consumers followed a "meat-free diet," including 6% vegetarians, 4% pescetarians, and 2% vegans. A 2018 survey showed that 10% of Canadian adults considered themselves vegetarians or vegans, with 42% of these people being young adults.

Studies on flexitarian eating habits have also been conducted in Australia and parts of Asia. However, estimates of how many people follow these diets vary widely depending on how surveys are carried out and how terms are defined. Researchers have also studied the reasons people choose to eat less meat.

Motivations

Some health-related reasons for choosing a flexitarian diet include managing weight, creating a more balanced and healthy diet, and being aware of overall health. Reducing meat is often done to improve diet quality and support long-term health goals. Flexitarian diets are sometimes described as a way to mostly eat plant-based foods while still eating meat occasionally. People who follow this diet may also follow public health advice to limit red meat, which has been linked to heart disease, cancer, and diabetes.

Environmental reasons for choosing a flexitarian diet include concerns about using too many natural resources and keeping food production sustainable. Meat production requires a lot of water and land, which are reasons some people reduce meat consumption for environmental reasons. Lowering meat consumption is discussed in the context of environmental vegetarianism and efforts to reduce the environmental impact of food systems. Many people are also worried about climate change, which is connected to greenhouse gas emissions from raising animals for food.

Ethical and economic reasons for choosing a flexitarian diet include following religious food rules, caring about animal welfare, and considering how food choices affect others. Some people reduce meat to use fewer resources or for economic reasons related to plant-based eating. Flexitarian diets are often talked about as a way to make food choices that match concerns about animal welfare and social responsibility.

Health effects

Flexitarian diets have been studied to learn how they might affect health and nutrition. However, the results can differ because people follow these diets in different ways. Some research shows that eating more fruits, vegetables, and grains may lead to better health. Studies also suggest that eating less meat, especially red meat, might lower the risk of certain long-term health problems, such as type 2 diabetes and heart disease. It can be hard to understand the research because different studies use different definitions for what a flexitarian diet includes.

Limitations

Research on flexitarian diets faces challenges due to differences in how the term is defined and how people follow these diets. A major challenge is the variety in how much meat people eat. Studies often use different rules to classify someone as flexitarian, such as eating meat only sometimes or having specific days with mostly plant-based foods. This makes it hard to compare studies, as health effects may differ based on how flexitarianism is described.

Another challenge is that much of the research linking flexitarian diets to health or environmental benefits comes from observational studies, not long-term controlled experiments. These studies help find patterns and possible effects, but they cannot prove direct cause-and-effect relationships. They may also depend on assumptions that vary between studies.

Nutritional results from flexitarian diets can also differ based on food choices and how the diet is planned. Poorly planned diets may lead to not getting enough important nutrients, while well-planned diets can meet general nutritional guidelines. This makes it difficult to predict health outcomes for all people who follow flexitarian diets, since each person’s diet is unique.

Varieties

The main idea of some flexitarian diets is not following a strict diet that completely avoids certain animal products, but instead focusing on reducing how often specific foods are eaten. Examples include:

• Demitarianism: This involves eating meat only about half as much as is common in many cultures. The term was created in October 2009 during a joint meeting between two groups in Barsac, France: Nitrogen in Europe (NinE) and Biodiversity in European Grasslands: Impacts of Nitrogen (BEGIN). They developed "The Barsac Declaration: Environmental Sustainability and the Demitarian Diet" during this meeting.
• Pescetarian diet: This includes eating fish and/or shellfish and may also include dairy and eggs. It avoids eating meat from poultry, mammals, and other land animals. In the past, some vegetarian groups considered this diet less strict, but today, most vegetarian groups do not allow eating fish or shellfish.
• Pollotarian diet: This includes chicken and other poultry, and often includes eggs. It avoids eating seafood, mammal meat, and other animal products, often due to environmental, health, or food justice reasons.
• Macrobiotic diet: This is a plant-based diet that sometimes includes small amounts of fish or other seafood. Brown rice and other whole grains are the main foods in this diet, with vegetables added occasionally. Supporters of this diet often encourage a vegetarian or nearly vegan lifestyle as the healthiest choice.
• Planetary health diet: This approach aims to provide enough food for the growing world population, reduce deaths caused by poor eating habits, and protect the environment to avoid harm to nature.

Dietary pattern

Semi-vegetarians can be described as people who eat mostly plant-based foods, but there is no clear agreement on how often someone must eat meat or fish for their diet to be called flexitarian instead of regular plant-based. A common feature of flexitarian diets is eating red meat or poultry once a week. One study said semi-vegetarians eat meat or fish three times a week. Sometimes, researchers say semi-vegetarianism means avoiding red meat completely, while flexitarianism means eating very little meat. In many parts of the world, diets based on plants are the main source of daily energy. This is often because people with higher incomes tend to eat more animal and dairy foods instead of plant-based staples. One estimate shows that 14% of the world’s population follows a flexitarian diet.

Society and culture

Flexitarianism has been talked about in public and media discussions about food choices and how people buy and use food. This idea is often described as a more flexible way to follow vegetarian or vegan diets, which may be why it is often mentioned in lifestyle topics. In the United Kingdom, more people wanted vegan products in 2018, which shows that more people are interested in eating less meat.

Environmental impact

Flexitarian diets have been studied, and research shows they may help protect the environment, especially when compared to diets that include a lot of red meat. Studies suggest that eating less red meat, such as in flexitarian diets, can lead to fewer greenhouse gas emissions than usual diets. Diets high in red meat have a bigger environmental impact because raising livestock needs a lot of land, food, and water. Compared to fully plant-based diets, flexitarian diets offer smaller environmental benefits but are easier for many people to follow.

In 2019, researchers from the EAT-Lancet Commission said that eating fewer animal products could help the environment and meet global nutrition needs better than typical Western diets. However, much of this information comes from computer models, and the environmental effects may vary depending on how each person follows a flexitarian diet.