A Review of the Flexitarian Diet 

Origin of the Flexitarian Diet | Overview of the Flexitarian Diet | Types of Flexitarianism | How Does the Flexitarian Diet Work? | Health Benefits of a Flexitarian Diet? | Benefit the Environment? | Can The Flexitarian Diet Lead to Weight Loss? | Experts Say | Bottom Line

Choosing the “right” diet is always a challenging proposition, especially given how many questionable fad diets come and go every year. Some publications, like U.S. News and World Report, attempt to help American consumers by ranking and reviewing various diets. For the last six years, the coveted number one spot has been held by the Mediterranean diet, an all-around healthy diet plan that is based on the traditional dietary patterns of people from a few well-known Mediterranean countries. Yet even though the diet consistently gets top marks, it may not be for everyone. That’s why the number two diet from that ranked list is a popular alternative for many people: the flexitarian diet.  

Origin of the Flexitarian Diet

The term “flexitarian” is a relatively recent addition to the dietary lexicon, having only been in use since the 1990s. The term—a portmanteau of “flexible” and “vegetarian”—was widely popularized by author and registered dietitian Dawn Jackson Blatner in her 2009 book, The Flexitarian Diet: The Mostly Vegetarian Way to Lose Weight, Be Healthier, Prevent Disease and Add Years to Your Life. As the wordy title implies, the whole essence of the flexitarian diet is to offer a compromise between a typical American omnivorous diet and a highly limited vegetarian diet. 

In the years since the book was published, other authors and social media content creators have further explored and expanded on the ideas of flexitarianism. One of the reasons it has gained and sustained popularity is the overall uptick in awareness of the potential value and health benefits of plant-based foods. But the purported benefits of vegetarian, semi-vegetarian, and vegan diets transcend individual weight management concerns; proponents also believe that shifting to a primarily plant-based diet can have a far-reaching impact on society-wide issues like sustainability, public health, and the country’s carbon footprint.     

Overview of the Flexitarian Diet

Advocates of the flexitarian diet have a variety of reasons for why they follow its principles, but those reasons tend to involve either personal health goals or social responsibility. In this sense, the diet is comparable to the Mediterranean, DASH, or MIND diets because it rarely is selected purely for weight loss. Instead, the main tenets of the diet are more about overall health and wellness:  

• Plant-based: Unsurprisingly, the cornerstone of the flexitarian diet is a strong emphasis on plant-based foods. This includes fruits, veggies, whole grains, legumes (such as beans and lentils), nuts, seeds, and plant-based protein sources like tofu and tempeh.
• Limited meat: While plant-based foods are obviously at the center, the flexitarian diet also allows for limited consumption of meat, poultry, and fish. Meat is typically considered an occasional or complementary component of meals, rather than the main focus.
• Flexibility: The “flex” part of flexitarian highlights the diet’s adaptability and openness to customization. Individuals have the freedom to choose when and how often they include animal products in their meals, and this flexibility can make it appealing to those who want to reduce their meat consumption without committing to a strict vegetarian or vegan diet.
• Healthy: At the core of the flexitarian diet is a fundamental motivation to be healthy and improve one’s relationship with food. And because of the diet’s emphasis on plants and the variety of healthy compounds they contain, it aligns with a lot of the principles of healthy eating recommended by medical professionals.  
• Eco-conscious: Many flexitarians are motivated by sustainability and environmental concerns. They believe that reducing meat consumption can have a positive impact on reducing greenhouse gas emissions and conserving resources like water and land.
• Nutrient density: Flexitarians generally tend to make nutrient-dense food choices as well as focusing on whole and minimally processed foods.
• Family-friendly: While some diets require strict adherence to a limited set of foods, the flexitarian diet allows for a lot of variability. This also makes it easy for families or groups of friends to follow the diet together; each individual can customize it based on their preferences and dietary needs. 
• Budget-friendly: Similarly, some diets (especially fad diets) require the purchase of special foods or ingredients that make it too expensive for many people. But the flexitarian diet’s customizability and emphasis on plant foods and unprocessed foods makes it financially accessible for more people. 

Types of Flexitarianism    

The nature of the flexitarian diet (also sometimes referred to as a semi-vegetarian diet) makes it very versatile and adjustable based on an individual’s preferences, beliefs, and lifestyle factors. Because of this, there are several types of flexitarianism that are typically differentiated by the amount of meat consumption allowed. This can range from essentially no meat at all to unlimited amounts of only certain kinds of animal proteins. Below are a few of the most common variations of the flexitarian diet: 

• Classic: The most common flexitarian approach is to follow a vegetarian or plant-based diet but occasionally include small amounts of meat, poultry, or fish. The overall emphasis is on plant foods, however, with animal products used sparingly. 
• Part time: There are numerous variations of the diet that all involve following a vegetarian or vegan diet at certain times only. For instance, some people eat strictly meatless meals Monday through Friday but are free to eat anything on Saturday or Sunday. Others eat plant-based meals most of the year and then allow unrestricted meat intake during holidays, special occasions, or for a particular season. 
• Reduced meat: Another approach favored by many is to simply eat less meat than they normally would but otherwise maintain an omnivorous diet. Some people inadvertently follow this type of diet pattern because health problems require eating less meat or less of a specific type of meat like red meat.   
• Pescatarian: Some flexitarians eat plant-based meals most of the time but then regularly include fish and other seafood as their primary source of animal protein. At the same time, they avoid red meat, poultry, and other animal proteins.
• Dairy: Another variation of the flexitarian diet is to eliminate animal products other than dairy and/or eggs. 
• Ethical: Some flexitarians base their food choices on ethical or sustainability concerns. So rather than limiting the amount or type of animal protein, they decide what is acceptable to eat after evaluating the environmental impact. An individual following this approach may even choose certain plant proteins over others because one is grown in a more sustainable way. 

How Does the Flexitarian Diet Work?     

Unlike diets that are solely interested in achieving substantial and rapid weight loss, the flexitarian diet is more of a lifestyle choice that stems from a particular worldview. For this reason, there are no rules about how many calories you can eat or a particular number of servings or any of the typical tropes we associate with diets. Instead, following a flexitarian diet is about aligning your eating patterns with the variation of the diet that works best for you. 

The fact that there isn’t a universally agreed-upon set of rules for the diet may make it less appealing for anyone looking for something more structured. In the original book that really popularized the diet, the author presents the flexitarian diet as almost a stepping stone to a full vegetarian or vegan lifestyle, but some people are content to live permanently in a state of just eating less meat in general; others might use the diet to cut out red meat specifically because of data that points to an increased risk of heart disease.  

This same openness to interpretation also makes the diet potentially more appealing, however, because of the low barriers to entry. Anyone could theoretically become a flexitarian by simply reducing the amount of meat they eat in a given day or week. In her book, Blatner suggests starting the process by evaluating your own eating habits. From there, each person can decide what, if any, changes they want to make to how much or what type of animal proteins they want to restrict or eliminate. In this sense, flexitarianism is like a choose-your-own-adventure diet.  

What Are the Health Benefits of a Flexitarian Diet?

Of course, one of the most popular reasons to follow a flexitarian diet is the purported health benefits. In the years since the diet first emerged, a number of studies have been done to investigate these potential health benefits. So far, there is significant evidence that a flexitarian diet can be beneficial in a variety of ways, depending on individual factors and specific choices. For a person who followed the principles closely and emphasized whole foods and plant-based proteins, here are some ways it could improve health: 

• Nutrient intake: Purely vegetarian and vegan diets often require vitamin and mineral supplements because plant foods alone don’t contain all of the essential nutrients required by the human body. But a well-balanced flexitarian diet provides dietary fiber, antioxidants, minerals like calcium and potassium, and vitamins like vitamin B12 and vitamin C. Such an emphasis on nutrient-dense foods gives the body everything it needs to maintain tissues, make repairs, and fend off the kinds of pathogens that lead to disease.  
• Digestive health: A diet high in plant-based foods necessarily contains a significant amount of dietary fiber. Sufficient daily fiber promotes healthy digestion, regular bowel movements, and a reduced risk of constipation and other gastrointestinal issues. 
• Heart health: One of the key contributors to heart disease is the consumption of saturated fats and dietary cholesterol, which are primarily found in animal-based foods like red meat and full-fat dairy products. By simply limiting or eliminating these foods as in the flexitarian diet, you reduce the risk of cardiovascular disease and other conditions related to the circulatory system. Limiting such foods and replacing unhealthy fats with healthy fats (like olive oil) can also lower blood pressure and the chances of cholesterol buildup in the arteries. 
• Reduced risk of chronic disease: Apart from heart health, a flexitarian diet can also generally lower the risk of developing a chronic disease. One of the biggest reasons for this is the abundance of antioxidants present in plant-based food. Antioxidants are compounds that protect the body from oxidative stress, a state that is believed to play a major role in the development of inflammatory diseases and even some types of cancer. 
• Metabolic health: The typical American diet is generally very high in processed foods that have a lot of refined sugars, and this is one of the reasons that obesity and metabolic problems like insulin sensitivity are so common. In recent years, though, extensive research has shown that diets like the flexitarian diet that emphasize whole, unprocessed, and fiber-rich foods are linked to improving insulin resistance and reducing the risk of type 2 diabetes. These foods also generally improve the body’s ability to regulate blood sugar. 
• Longevity: While the secrets to living a longer and healthier life aren’t fully known, research from the last few decades has shown that a diet like the flexitarian diet can also potentially lead to a longer lifespan. This can be explained by the overall aggregate effects of all the various health benefits offered by a healthy diet. 

How Does Flexitarianism Benefit the Environment?

As noted above, people may be motivated to adopt a flexitarian diet or lifestyle for a number of different reasons. For some people, the potential health benefits are the only or main consideration. For others, though, going flexitarian is about a larger sense of social responsibility. In light of climate change and seemingly unsustainable agricultural practices, the flexitarian diet represents an opportunity to take a stand or contribute to an important cause. Below are some ways flexitarianism can benefit the environment: 

• Reduced emissions: One effect of animal agriculture that may not be immediately obvious is that it is a major contributor to greenhouse gas emissions. Animals like cows and pigs generate a substantial amount of methane and nitrous oxide, two gasses that are known to be involved in global warming. By switching to a primarily plant-based diet, we can gradually lower the impact of animal agriculture and our carbon footprint. 
• Land conservation: Animal agriculture generally requires much more land and water than farming plants. So widespread adoption of flexitarian practices can theoretically free up land and water resources for other types of farming.
• Less energy: Plant-based foods also tend to require less energy to produce than animal products, and these savings can come in the form of anything from less refrigeration to shorter supply chains.  

Can the Flexitarian Diet Lead to Weight Loss?

As a guiding philosophy for maintaining a healthy diet or being environmentally conscious, the flexitarian diet is a solid option. The truth is, though, that most people evaluate a diet based on how much body weight they’ll be able to lose. Even though the flexitarian diet ultimately isn’t designed with weight loss in mind, it nevertheless can be a framework that leads to weight loss. In order to achieve weight loss, though, you’ll have to ensure a calorie deficit just like with any other diet. 

One of the ways the diet can potentially promote weight loss is through eating fewer processed foods that are high in fat or sugar. Many of these foods have a lot of refined carbohydrates; in addition to increasing blood sugar levels and raising the risk of insulin resistance, foods high in refined carbs tend to not be as filling. This means you’re likely to be hungry again more quickly compared to eating lean proteins or grains like quinoa or brown rice. Foods high in protein and fiber leave you feeling full and can even reduce cravings for sugar.   

What Do the Experts Say? 

Lori Gooch, RDN, LDN, a registered dietitian at True You Weight Loss, offers some insight into commonly asked questions about the flexitarian diet:

What are the pros/cons of a flexitarian diet? What type of people may benefit from this diet, and who should avoid this?

• The flexitarian diet is a flexible approach to eating mostly plant-based foods while still incorporating some meat and animal products. When following this style of eating, it allows the individual to have the flexibility to make choices based on their preferences and nutritional needs. This style of eating mainly follows a vegetarian diet. It promotes consuming a variety of plant-based foods such as fruits, vegetables, legumes, whole grains, nuts, seeds, and plant-based protein sources. They occasionally include small amounts of meat, poultry, fish, or dairy products. 
• The flexitarian diet is associated with several potential health benefits, including weight management, reduced risk of chronic diseases like heart disease, diabetes, and improved overall well-being. By prioritizing plant foods, this approach incorporates more fiber, vitamins, minerals, and antioxidants. Additionally, it allows the individual to adapt their food choices to individual preferences, dietary restrictions, and cultural or social situations. It is important to note that those choosing to eat a flexitarian diet should be mindful of nutrients including protein, iron, vitamin B12, and omega-3 fatty acids, which can be less abundant in a plant-based diet.
• A flexitarian approach may not be the best option for those with severe meat allergies and/or intolerances, specific health conditions, or those that require strict dietary requirements.

What have you found people are generally unaware of when considering the flexitarian diet?

• While plant-based foods are nutrient-rich, it may lack in other important nutrients including protein, iron, vitamin B12, and omega-3 fatty acids. 
• It can be easy to unintentionally consume excessive calories and saturated fats if animal products are overemphasized in meals. It is important to be mindful of portions. 
• Quality matters when choosing meat and plant-based alternatives. Individuals should choose lean cuts of meat, poultry, and seafood. If possible, limit highly processed plant-based options such as veggie burgers, meat substitutes, or vegan junk food. These products can be high in salt, sugar, and fats. A balanced diet should focus on whole, fresh foods. 
• Lack of variety can be common for those eating in a routine of the same foods. However, it is beneficial to incorporate a variety of fruits, vegetables, and other plant-based foods to have a broader spectrum of nutrients. 
• Lack of planning ahead for meals, social situations, and dining out can make eating a flexitarian approach more challenging. It is important to be aware that planning balanced meals and snacks takes some effort. Without proper planning, it can be easy to default to convenience foods or revert to a less balanced diet.  

Do you have firsthand experience with the flexitarian diet, whether it’s something that you’ve personally tried, or have seen others be successful or unsuccessful with? Share as many details as you’re able.

• While I don’t have personal experience with the flexitarian diet myself, it is beneficial to aim to incorporate more fresh, whole foods, fruits, vegetables, and lean protein sources. Strong evidence shows that this style of eating promotes healthy weight loss and improved metabolic health benefits, including reduced diabetes risk and blood pressure.

How much weight do people typically lose with a flexitarian diet?

• Weight loss for those that eat a flexitarian diet will vary depending on several factors including overall calorie intake, physical activity level, adherence to the diet, and can be highly individualized. It is important to be mindful that sustainable and healthy weight loss is best achieved through a combination of a balanced diet, portion control, regular physical activity, and individualized planning. 

For someone that might be considering the flexitarian diet, what alternative options should they consider and why?

• A vegetarian diet eliminates meat and seafood but includes plant-based foods like fruits, vegetables, grains, legumes, nuts, and seeds. This may be an option for those that want to remove most animal products from their diet.
• A vegan diet eliminates all animal products, even those produced by animals such as honey, eggs, or dairy and are committed to a fully plant-based lifestyle.
• A pescatarian diet includes fish and seafood but excludes other meats. This may be an option for those that want to reduce meat consumption while still enjoying the health benefits of seafood. 
• The Mediterranean diet focuses on fruits, vegetables, whole grains, olive oil, and moderate amounts of lean protein and is linked to heart health and longevity. This is a great approach for those wanting a balanced diet with an emphasis on whole foods and healthy fats. 

Bottom Line 

The flexitarian diet is an undoubtedly healthy and versatile approach to eating that may appeal to many different people. The core tenets of the diet align with numerous healthy eating principles that doctors have identified in recent decades. The flexibility allows you to incorporate it into your life in a personal way, and the environmentally conscious sensibility makes it relevant and worthy of note in light of global warming and climate change. Will it help you lose weight, though? While the diet isn’t designed for that purpose, it can be a useful framework for weight loss in some circumstances. Overall, though, there’s nothing unique about the diet that makes it more effective for weight loss than any other method. 

Contact True You Weight Loss     

If you’re trying to lose weight and you have strong beliefs about how food choices can affect the environment, the flexitarian diet is a great choice. For many people trying to lose weight, though, no diet or meal plan alone is likely to lead to lasting change. That’s why at True You Weight Loss we are proud to offer an alternative approach to weight loss that starts with a non-surgical endobariatric procedure like ESG or a gastric balloon. If you’d like to learn more about how we can help you finally find the freedom you’ve been looking for, please contact us today to request a consultation.