The Flexitarian Diet: A Detailed Beginner’s Guide

Plant-based diets have become increasingly popular over the years.

This rise in popularity is likely related to sustainability, animal welfare, and ethical concerns of meat-based diets, as well as an increased awareness surrounding the health benefits of a plant-based diet.

Although these factors are becoming more important to people, not everyone is willing to restrict animal-based foods completely and go vegan.

Alternatively, the flexitarian diet offers some middle ground between a vegan and meat-based diet by allowing some animal products.

Here’s a detailed beginner’s guide to the flexitarian diet, explaining its health benefits, how to follow it, and more.

What Is a Flexitarian?

A flexitarian is an individual who follows a primarily vegetarian diet but occasionally eats meats, seafood, and dairy.

A vegetarian is a general term used to refer to a diet that excludes meat and other animal products from the diet.

All flexitarians are vegetarians, but not all vegetarians are flexitarians.

Other types of vegetarians include:

• Pescatarian: One who eats fish and other forms of seafood.
• Lacto-vegetarian: One who includes dairy in their diets.
• Ovo-vegetarian: One who includes eggs in their diets.
• Lacto-ovo-vegetarian: One who includes both dairy and eggs in their diets.
• Pollotarian: One who includes chicken, turkey, and other types of poultry in their diets.
• Vegan: One who eliminates all animal-based products from their diets. This is the strictest type of vegetarian diet.

Here are the basic principles of the flexitarian diet:

• Eat mostly plants, like fruits, vegetables, legumes, and whole grains
• Get most of your protein from plants
• Eat foods in their whole or least processed forms
• Include animal products some of the time

Currently, there is no clear consensus on what defines a flexitarian diet in terms of the amounts or types of animal products allowed or the frequency in which you can consume them. (1)

As such, there are a variety of approaches to the diet, allowing you to adapt the diet based on your preferences and goals.

Flexitarian Diet Benefits

A flexitarian diet may offer many health benefits.

However, the definition of a flexitarian diet differs among studies, making it difficult to link the findings to the flexitarian diet (rather than a different plant-based diet) directly.

Still, like other plant-based diets, the flexitarian diet consists primarily of fruits, vegetables, whole grains, and legumes, while limiting added sugars, refined grains, and meats, especially processed and red meats.

As such, research on plant-based diets is still helpful in showing how a flexitarian diet can benefit health.

Can Promote Fat Loss

Fat loss is a common goal shared by many people.

While many dietary patterns can promote weight loss, a plant-based diet is particularly helpful since it is loaded with fiber-rich foods that promote satiety.

Plant-based diets like the flexitarian diet also eliminate ultra-processed foods like soft drinks, candy, sweetened breakfast cereals, processed meats, and fried foods that can drive hunger and food intake, resulting in weight gain over time. (2)

A review of 22 studies found that people who followed a plant-based diet for at least 10 weeks significantly reduced their body weight compared to those on a standard diet. (2)

As a result of this weight loss, many of the people in the studies also experienced other health benefits, such as reductions in blood pressure, cholesterol, and insulin resistance.

Can Reduce Diabetes Risk

Type 2 diabetes is a common disease in which the body doesn’t use insulin properly, causing high blood sugar or glucose levels.

Insulin is the hormone that lowers blood glucose by transporting it to your cells for storage or energy.

Plant-based diets have been shown to support healthy blood glucose levels by improving insulin sensitivity, allowing the body to use the glucose more effectively.

This improvement in insulin sensitivity occurs largely due to the diet’s rich fiber and polyphenol content.

Polyphenols are beneficial plant compounds with strong anti-inflammatory and antioxidant properties, which help reduce inflammation and oxidative stress that can impair insulin sensitivity.

One study involving three large cohorts showed that adherence to a plant-based diet over four years was associated with a lower risk of type 2 diabetes, whereas a decreased adherence was associated with a 12%–23% higher risk of developing diabetes. (3)

In people with diabetes, a plant-based diet can also help improve blood glucose control and prevent diabetes-related complications like nerve damage, eye damage, and heart disease. (4)

Can Lower Blood Pressure

High blood pressure is a major risk factor for heart disease and other diseases like chronic kidney disease.

Plant-based diets are rich in a number of nutrients like potassium, magnesium, and nitrate that help lower high blood pressure and maintain healthy levels by improving endothelial function.

The endothelium is a layer of cells that lines the inside of the heart and blood vessels. These cells release chemicals like nitric oxide that dilate vessels and promote blood flow.

A review of 41 studies involving more than 12,000 people showed that a plant-based diet was associated with a 4.20 mmHg reduction in systolic (the top number) blood pressure and a 2.79 mmHg reduction in diastolic blood pressure compared with a control diet. (5)

May Reduce Gut Inflammation

Inflammatory bowel disease (IBD), like Chron’s disease and ulcerative colitis, occurs as a result of a defective immune system.

The composition of the gut microbiota plays a key role in immune health and is thought to play a vital role in the development of IBD. (6)

The Western diet, also known as the standard American diet, is low in fiber but rich in saturated, refined carbs, and sodium.

Due to the lack of fiber and other nutrients, the Western diet is associated with a reduced gut microbial diversity, or dysbiosis, which can increase one’s susceptibility to IBD and other common diseases. (7)

Conversely, plant-based diets are associated with increased microbial diversity and reduced inflammation.

As a result, plant-based diets may offer protective effects against IBD or provide symptom relief in people with IBD. (1)

Flexitarian Diet Downsides

There aren’t necessarily any downsides to the flexitarian diet, but you should be aware of certain things.

Animal products contain some nutrients that plants either don’t have or only have in limited amounts.

These nutrients include: (8)

• Vitamin B12
• Vitamin D
• Creatine
• Carnosine
• Eicosapentaenoic acid (EPA)
• Docosahexaenoic acid (DHA)
• Heme iron
• Taurine

Depending on how much you restrict animal products from your diet, you may need to supplement with one or more of these nutrients.

Even if you eat animal products a few times per week, you may still need a supplement.

For example, regardless of diet, many people are either deficient in vitamin D or have insufficient levels, making a supplement necessary. (9)

Even lacto-ovo-vegetarians, who can get plenty of vitamin B12 from dairy, have been reported to have lower levels of the vitamin than meat-eaters. (10)

Creatine is another nutrient where supplementation would be beneficial on a flexitarian diet, especially if you’re an athlete.

Creatine is naturally found in animal protein, so compared with their meat-eating counterparts, vegetarians have reduced stores. (11)

Supplementing with creatine can enhance muscle size, strength, and power by 10%–20%, with potentially greater increases in vegetarians. (12)

In either case, it’s still possible to get enough of the nutrients you need on a flexitarian diet, depending on your level of animal product restriction, with some careful planning. 

How to Get Started

With no current standardized definition for a flexitarian diet, you can choose what animal products you allow and in what amounts.

Start by analyzing your current diet and decide what you’re comfortable with eliminating or reducing.

Your starting point will look different than others based on the frequency, amount, and types of animal products you currently eat.

If you eat meat every day, maybe you reduce your intake to three times per week while allowing dairy and seafood in moderation.

Or if you eat meat three times per week, maybe limit it to once a week, including other animal products just as often.

Making smaller changes can help reduce stress and allow you time to plan and find plant-based alternatives for what you eliminate.

This is especially important if you frequently eat home-cooked meals and cook for others in your family.

Over time, you can decrease the frequency or types of animal products you restrict from your diet.

Foods to Eat and Limit

The flexitarian diet emphasizes mostly whole, minimally-processed plant foods while limiting animal products.

Foods to Eat

Foods that should comprise most of your diet include:

• Fruits: Apples, avocados, bananas, berries, cherries, grapes, melons, plums, oranges, pears, etc.
• Vegetables: Arugula, asparagus, beets, broccoli, cabbage, carrots, corn, kale, mushrooms, onions, peppers, potatoes, spinach, tomatoes, etc.
• Whole grains: Amaranth, barley, buckwheat, bulger, oats, popcorn, quinoa, whole-grain bread, pasta, and rice.
• Proteins: Beans, edamame, lentils, nuts, peas, peanuts, tofu, tempeh, seeds, etc.
• Plant-based dairy alternatives: Unsweetened almond, coconut, rice, and soy milk.
• Oils: Canola, avocado, and extra-virgin olive oil.
• Beverages: Unsweetened coffee and tea, water, and other calorie-free beverages.

Incorporate these animal products in moderation:

• Poultry: Skinless chicken breasts, duck, eggs, goose, quail, and turkey.
• Seafood: All fish and shellfish.
• Meats: Lean cuts of beef and pork that have “loin” or “round” in their name.
• Dairy: Cheese, cottage cheese, Greek yogurt, and milk.

Foods to Limit

Limit ultra-processed foods as they can have detrimental effects on health in large amounts.

Foods to limit include:

• Sugary drinks (regular soda, energy drinks, sweetened coffee and tea)
• Candy and chocolate
• Ice cream and other frozen desserts
• Fried foods (churros, french fries, onion rings)
• Bakery products (donuts, cakes, rolls, muffins)
• Processed meats (bacon, bologna, deli meats, sausage)
• Packaged snacks (chips, fruit snacks)
• Highly processed meat alternatives (many plant-based “burgers” and “chicken nuggets”)

3-Day Sample Flexitarian Diet

Here is a 3-day sample flexitarian diet plan to get you started.

Day 1

• Breakfast: Oatmeal topped with raspberries, and tofu scramble with spinach
• Lunch: Chickpea salad sandwich
• Snack: Hummus with veggies for dipping
• Dinner: Vegetarian meatballs with whole-grain pasta and a side salad

Day 2

• Breakfast: Breakfast burrito with spinach, feta cheese, tomatoes, black olives, and refried beans
• Lunch: Teriyaki cauliflower rice bowl with cooked edamame
• Snack: Greek yogurt with almonds
• Dinner: Grilled chicken salad

Day 3

• Breakfast: Egg-and-vegetable scramble with avocado toast
• Lunch: Cottage cheese toast
• Snack: Apple slices with peanut butter
• Dinner: Baked salmon with a roasted sweet potato and asparagus spears

This 3-day sample includes one serving of meat along with some dairy, seafood, and eggs. You may choose to eat fewer animal products than this example.

Frequently Asked Questions

The Bottom Line

The flexitarian diet is a semi-vegetarian way of eating that focuses on mostly whole plant foods but allows some animal products in moderation.

Eating flexitarian can promote weight loss, decrease diabetes risk, lower blood pressure, and offer benefits for people with IBD.

A carefully-planned flexitarian diet can provide all the nutrients you need in adequate amounts, but a supplement may be necessary depending on the amount and type of animal products you restrict.