What Is a Flexitarian Diet, and Is It Healthy?

A 2020 Gallup survey found 23% of Americans had cut back on meat in the previous year, with many turning to plant-based alternatives.

No formal definition of a semi-vegetarian diet exists. However, being a semi-vegetarian—also known as a "flexitarian" (or "flexible vegetarian")—often means you mostly eat plant-based foods and occasionally eat chicken, fish, dairy products, and eggs, and rarely (if ever) eat red meat. Semi-vegetarianism aims to lessen, rather than eliminate, your meat consumption by focusing on plant-based foods.

Here's how adopting a semi-vegetarian diet can improve your health—and the health of the planet.

What Is a Flexitarian?

A semi-vegetarian or flexitarian diet would theoretically indicate being a part-time vegetarian. This means a person follows a vegetarian diet some or even most of the time but does not commit to it fully. That may mean allowing eggs and dairy daily or frequently but limiting meat, poultry, and seafood to whatever feels right for you.

Unlike semi-vegetarian, the terms vegan and vegetarian have formal definitions.

Veganism excludes all animal products, meaning no meat, poultry, seafood, eggs, dairy, or any ingredients derived from animal sources, including honey and gelatin. Veganism may also extend to a lifestyle that involves not using any materials derived from animals, including leather, fur, wool, and silk, nor cosmetics or soaps made with or tested on animals.

Vegetarianism generally means that no meat, poultry, or seafood is consumed, but eggs and/or dairy are included, with no specified amount or frequency. Beyond veganism and semi-vegetarianism, other types of a vegetarian diet include:

• Lacto-vegetarianism: A diet of plant foods and some or all dairy products
• Lacto-ovo vegetarianism: A diet of plant foods, dairy products, and eggs
• Pescatarianism: A diet of plant foods and seafood

Vegetarians may also consume meat substitutes, ranging from whole foods like lentils or beans to faux meats like veggie burgers.

Some flexitarians don't eat dairy but eat eggs and seafood. Others avoid eggs but include yogurt or cheese and use animal-derived collagen or take a fish oil supplement.

A semi-vegetarian diet can technically include any combination of vegetarian and animal-based foods. Still, the more plant-based food you have in your diet, the more you'll likely benefit health-wise.

For this reason, it may be best to lay out some sort of structure, such as eating vegetarian Monday through Friday, eating two vegetarian meals a day, or making all home-cooked meals vegetarian.

Health Benefits of a Flexitarian Diet

In a 2020 Gallup survey, the top reason cited for consuming less meat was health, with nine out of 10 people naming it as a factor. Trading meat for nutrient-rich, plant-based alternatives more often can play a significant role in protecting your health. For example, eating less meat can reduce blood pressure.

A 2019 meta-analysis looked at plant-based eating patterns, defined as eating more plant- and fewer animal-based foods, and the incidence of type 2 diabetes.

The researchers found that plant-based dietary patterns were linked to a lower risk of type 2 diabetes, even after adjusting for body mass index (BMI), meaning the effect held true regardless of body weight.

In a 2020 study, researchers looked at data from more than 400,000 people in the U.S. over a 16-year period. They found that a higher intake of plant protein was associated with a lower risk of death from all causes. The link particularly held true for heart disease, which remains the number one killer in the U.S.

Research also shows that exchanging animal protein for plant protein improves several heart disease risk factors, including cholesterol, body weight, and body fat percentage.

In a 2020 Stanford study, participants were asked to consume two or more servings per day of either animal protein (mainly red meat) or Beyond Meat (a plant-based "meat") for two months while keeping all other foods and drinks as similar as possible. The subjects then consumed the reverse pattern for another eight weeks.

The researchers of the Stanford study found that compared to meat, Beyond Meat consumption improved heart disease risk factors. Effects included a reduction in "bad" LDL cholesterol, modest weight loss, and lower blood levels of a compound linked to blood vessel inflammation.

Foods To Include

A 2019 study followed over 800 people who were either vegans, lacto-ovo vegetarians, semi-vegetarians, or non-vegetarians. Researchers found vegans had higher levels of healthy fats, antioxidants, and anti-inflammatory compounds in their bodies. However, the outcome was likely because vegans consume more whole plant-based foods, including produce, whole grains, nuts, and pulses.

Pulses—the umbrella term for beans, lentils, peas, and chickpeas—are a filling, nutrient-rich, and versatile plant protein option. This food group has been shown to support healthy weight management and fat loss, even when a diet isn't intended to reduce calories.

Thus, you'll want to opt for pulse-based entrees like lentil or black bean soup and bean and vegetable chili or stew. You could replace meat, seafood, or poultry with chickpeas or black-eyed peas in a stir fry, salads, and grain bowls.

A balanced semi-vegetarian diet should include the following foods each day:

• Three to five servings of vegetables
• Two to three servings of fruit
• A variety of nuts and seeds
• Whole grains such as oats, quinoa, and brown or wild rice

Foods To Eat in Moderation

The animal products you choose to include in your flexitarian diet are ultimately up to you, but red meat is generally discouraged. If you opt for vegetarian meat substitutes, keep an eye on their sodium levels.

Fortunately, with so many plant-based products on the market, eating meatless meals is easier than ever. However, filling your cart with frozen vegan pizzas and mac and cheese isn't the best way to benefit from a more plant-based diet.

Overall, it's best to limit foods with high levels of unhealthy fats, sodium, and sugar. Many plant-based meat substitutes don't have the healthiest nutritional profile. Plant-based goodies, like vegan ice cream and baked goods, are fine as occasional treats, but they shouldn't crowd out whole, nutrient-rich plant foods.

To get more key nutrients, try swapping out white rice, bread, and pasta for whole grains.

Risks and Limitations of a Flexitarian Diet

Some people who adopt flexitarian diets may have eating disorders or depression. Contact a healthcare provider if you show signs of disordered eating or other mental health issues.

When switching to a flexitarian diet, you need to ensure you're getting all the nutrition you need. The following groups of people may need to plan their diets more carefully:

• Older adults
• People who are pregnant or breastfeeding
• People with health conditions
  
• Teenagers and young children

People who belong to any of the above categories—especially teenagers and pregnant people—should work with a registered dietitian if they want to switch to a flexitarian diet.

If you find it hard to get certain nutrients, try some of the following tips to incorporate them into your diet.

How To Get Enough Nutrients

Just as it is important to choose the right foods if you intend to follow a semi-vegetarian diet, it is crucial to get enough nutrients in your diet.

Depending on how you plan to become a semi-vegetarian, you'll want to ensure you get vitamins and minerals such as vitamins B12 and D, zinc, iron, calcium, omega-3 fatty acids, and protein. The following are a few examples of foods that can help you build up those nutrients:

• Vitamin B12: Eggs, dairy products, nutritional yeast, seafood
• Vitamin D: Fatty fish, egg yolks
• Zinc: Beans and legumes, nuts and seeds, seafood, yogurt, or cheese
• Iron: Beans and legumes, green vegetables, dried fruit, whole grains
• Calcium: Sardines and canned salmon, dairy products, green vegetables, almonds, oranges, figs, tofu
• Omega-3 fatty acids: Fatty fish, nuts and seeds, soybeans, and soy oil
• Protein: Soy foods, vegetarian meat substitutes, legumes, beans, lentils, nuts or nut butters, seeds, whole grains, dairy products
  

Furthermore, eating fortified foods that contain the nutrients above, and taking supplements, if necessary, can also help you get enough nutrients in your system.

Flexitarianism Helps the Planet

The climate crisis is a public health emergency, and eating fewer animal-based foods is part of the solution.

A Harvard report called The EAT-Lancet Commission on Food, Planet, Health, which calls for a primarily plant-based diet, states, "Food is the single strongest lever to optimize human health and environmental sustainability."

The environmental impact of meat consumption includes the production of greenhouse gas emissions from livestock, a greater use of natural resources (including water and fuel) compared with plant food sources, and contamination of water, air, and soil.

A 2019 study found that meatless meals have more than a 40% reduction in environmental impacts. These include carbon footprint, water use, resource consumption, health impacts of pollution, and ecosystem quality. Simply eating one plant-based meal per day can have a significant environmental impact.

How To Start a Semi-Vegetarian Diet

The benefits of being a semi-vegetarian are numerous. If you're just getting started, try this three-step approach.

1. Create a plan for which animal-based foods you'd like to keep and which you're willing to give up (even for a 30-day trial). Do the same for which plant-based alternatives you'd like to eat more often.
2. Decide roughly how many vegetarian or entirely plant-based meals you'd like to eat per day or per week.
3. Seek out healthful, go-to options, including recipes, products to try, and takeout, or meal kit and delivery selections. Have fun experimenting, and pay attention to how your body responds.

If you have any special dietary needs, such as food allergies, or a medical condition that requires a therapeutic diet, consider consulting with a registered dietitian who can tailor a semi-vegetarian diet to your body's needs.

A Quick Review

With a flexitarian diet, you can reap the benefits of a mostly plant-based diet without getting rid of meat entirely. A semi-vegetarian diet can have many health benefits, such as reducing your risk of heart disease, type 2 diabetes, and more.

If you adopt a flexitarian diet, you just need to ensure you're not missing out on any nutrients. If that's a concern for you, work with a registered dietitian.