Your Guide to the Vegetarian Diet for Weight Loss

May 19

This story was published on LoseIt!.

The vegetarian diet is associated with a number of highly positive health outcomes. We interviewed four experts to walk you through the ins and outs of the vegetarian diet — including what to eat and avoid — to set you up for success, no matter your health goals.

Expert Reviewed by Sean Hashmi, MD, MS, FASN

With a remarkably long history dating back to the sixth century B.C., vegetarianism has spanned cultures, continents, and millennia. Today, the vegetarian diet continues to grow in popularity, largely owing to an increasing awareness of the negative impact of meat overconsumption on both human and environmental health, as well as the numerous benefits associated with plant-based eating.

What Is the Vegetarian Diet?

While “vegetarianism” is a broad term that encompasses various types of eating (more on this later), the diet generally emphasizes eating fewer animal products and more plant-based foods, says Rhyan Geiger, RDN, founder of Phoenix Vegan Dietitian in Arizona.

Historically, people have lived a vegetarian way of life for religious and ethical reasons. In the 21st century, scientific evidence began supporting the idea that vegetarian nutrition reduces the risk of many contemporary diseases, which shifted prejudices against vegetarianism leading to malnutrition, according to research.

Nowadays, interest in vegetarianism is increasing globally, with many individuals choosing this diet for the pursuit of health, a concern for animal welfare, and a desire to reduce one’s carbon footprint. In North America alone, approximately 6 percent of the population is vegetarian.

Nadja Abada, RD, at JM Nutrition in Toronto, Ontario, explains that “the power of plant-based diets comes from their phytochemicals,” which have antioxidant properties that protect our cells and DNA from damage, as well as gut-friendly fiber and resistant starch, which can help keep blood sugar stable, boost heart health, and prevent intestinal-related diseases.

“We see a lot of health benefits across the spectrum,” says Julieanna Hever, RD, a Thousand Oaks, California–based nutrition and fitness counselor and author of books including The Choose You Now Diet and Plant-Based Nutrition (Idiot’s Guide). “The fewer the animal products, the more we see reduced risk for cardiovascular disease, type 2 diabetes, and other cardiometabolic diseases.”

Does the Vegetarian Diet Work for Weight Loss?

The vegetarian diet can be healthy and effective for weight loss if you’re eating wholesome foods and creating a calorie deficit, says Hever. Aim to focus on the least calorie-dense foods — vegetables, fruits, legumes, and whole grains — instead of fried or processed foods, which are often low in nutrients and high in sugars, sodium, and less healthy fats.

Additionally, there is an association between eating quality plant-based protein and decreased BMI, lower visceral fat, and improved insulin resistance, according to a study.

How Does the Vegetarian Diet Impact Hunger?

“Whole plant-based foods are lower in calories, allowing people to eat more food with less calorie intake, which can lead to weight loss,” says Geiger, but “because plant-based foods are lower in calories, it’s easier to undereat when you start a plant-based diet.” This can lead to more frequent feelings of hunger.

To ensure you’re getting the proper nutrition and feeling satiated, you’ll want to plan out your vegetarian diet with good-quality meals and snacks. Focus on eating fiber-rich whole foods, says Hever. “Fiber is essential for satiety. It fills up and touches the receptors in the stomach to trigger the brain [and let it know] that you’re full.”

How Much Weight Can You Lose on the Vegetarian Diet?

A meta-analysis of randomized clinical trials found that those who practice the vegetarian diet lost 4.4 pounds more than non-vegetarians over a median duration of 18 weeks.

According to researchers, a potential explanation for the weight reduction can be attributed to the high intake of whole grains, fruits, and vegetables that vegetarians typically consume. All of these foods are high in dietary fiber, which has a significant association with lower body weight, the study authors write.

While further research is needed to investigate the longer-term effects of vegetarian diets on weight control, the results are promising. “Vegetarian diets, and vegan diets in particular, appear to have beneficial effects on weight reduction,” say the authors of the study.

How Does the Vegetarian Diet Compare to Other Diets for Weight Loss?

According to the same meta-analysis mentioned above, while vegetarian diets appear to have beneficial effects on weight loss compared to the typical non-vegetarian eating plan, more research is needed to analyze the effectiveness of the vegetarian diet in a head-to-head comparison with other diets for weight loss, as Frank Hu, professor of nutrition and epidemiology at Harvard and an author of the study, told The Salt.

That said, there is one study that analyzed a small group of young adults who experimented with vegetarianism and other weight-loss diet methods, including counting calories and consuming fewer calories. “Duration of the vegetarian diet was much greater than the weight-loss diet; most participants in the vegetarian group (62 percent) remained on their diet for more than one year, whereas the majority of the weight-loss participants (61 percent) followed their diet for one to three months,” the authors write.

While the study’s results are promising, more research is needed to determine how much weight was lost on the diets and how long the weight loss was maintained, say the authors.

Types of the Vegetarian Diet

According to Abada, there are four main categories that encompass vegetarianism today. While the different types of vegetarian diets all include plant-based foods, some variations allow for the addition of distinct animal products.

The main types of vegetarianism include the following diets.

Lacto-Ovo Vegetarian

This is the main type of vegetarianism. This diet includes eggs and dairy.VeganVeganism is a strictly plant-based diet, excluding meat, seafood, poultry, eggs, dairy, and honey.

Pesco-Vegetarian

Also known as pescatarianism, this diet includes fish, eggs, and dairy.

Semi-Vegetarian

Commonly referred to as flexitarianism, this diet allows meat and poultry on rare occasions.

Vegetarian Diet Subtypes

There are some vegetarian diet subtypes as well, says Abada. “In between the four main categories, you can find ovo-vegetarians, who choose to eat eggs and exclude dairy products, as well as lacto-vegetarians, who include dairy products while excluding eggs.

”Pros and Cons of the Vegetarian Diet, According to a Lose It! Dietitian

We spoke with Lose It! in-house registered dietitian Anna Smith, who gave us the pros and cons of the vegetarian diet.

Pros of the Vegetarian Diet

Heart Healthy

“The vegetarian diet is a big hug for your heart,” Smith says. “Research suggests that following a plant-based diet can slash your risk of cardiovascular disease and coronary heart disease by 40 percent. Plus, it’s not just about prevention; [the same] research supports that a vegetarian diet may actually reverse your heart disease.”

Improved Mood

“Eating more raw fruits and vegetables is great for boosting your mood and lowering depression, leading to better life satisfaction,” Smith says. According to this study, the fruits and vegetables that can improve mental health include carrots, bananas, apples, dark leafy greens, and more.

Better Weight Management

According to a study, a higher intake of meat consumption is linked to a higher risk of obesity, while a higher intake of vegetables can reduce the chances of weight gain and being at a higher weight, Smith says. “Making the switch from meat to veggies — just as you would on a vegetarian diet — can be a smart move in achieving a healthy weight.”

More Environmentally Friendly

“Going for more plant-based foods is good for you and the environment,” Smith says. “That’s because plant-based foods tend to leave a much smaller mark on our planet compared to animal products.”

Cons of the Vegetarian Diet

Nutritional Deficiencies Are a Risk

“Pay attention to essential nutrients like vitamin B-12, iron, zinc, and calcium; these are often lacking in a vegetarian diet,” says Smith. While it’s possible to meet current recommendations for these nutrients with a well-planned diet, it may be useful to add supplementation and fortified foods to better guard against deficiency.

Not All Plant-Based Foods Are Created Equal

Just because something is meat-free does not automatically make it healthy. To gain the most benefits from vegetarianism, you’ll want to make sure you’re not overdoing the amount of highly processed or refined foods you’re eating, Smith says. These foods are lacking in nutrients and eating too much of them can increase morbidity and mortality.

It Can Be Too High in Carbohydrates

“One thing I see [vegetarians] struggling with is going too high in carbohydrates — especially low-fiber carbohydrates like refined grains and sugars, which can spike your blood sugar levels,” Smith says. “Plus, they don’t provide the same satiety and nutritional benefits as fiber-rich carb options.”

Social Gatherings Can Get Tricky

Navigating holidays or social gatherings may take extra effort, especially when the main dishes at these gatherings are meat-centric, says Smith. “With some planning and communication, however, it’s totally doable to ensure there are delicious vegetarian options available.”

For the next gathering, Smith suggests bringing your own plant-based burgers or coordinating with the host to ensure you have meat-free options.

What to Eat and Avoid on the Vegetarian Diet

To get the most benefits from the vegetarian diet, you’ll want to ensure you’re following one that is well planned. And the more consistently wholesome your vegetarian eating plan is, the easier it will be to stay on track with your goal, whether it be weight management, improved health, or another objective.

What to Eat

According to Abada, the best vegetarian foods to eat for weight loss include a variety of vegetables and low-glycemic index fruits; whole grains; legumes; various nuts and seeds; healthy fats such as olive oil or avocado oil; and a moderate amount of starchy vegetables, baked goods, and healthier treats. “Choose treats that have the fewest ingredients and lowest amount of added sugars per portion,” she suggests.

The keys here are quality and variety. Choosing a myriad of healthy plant-based foods will increase the likelihood you’ll be getting the essential nutrients you need to fuel your body throughout the day. You’ll also minimize deficiencies or surpluses of single nutrients by opting for variety-filled meals.

Here’s a helpful breakdown of the best foods to eat to ensure you’re meeting your nutritional needs.

Protein: For lacto-ovo vegetarians, eggs, cheese, and yogurt are complete proteins that contain all the essential amino acids to sustain you, says Abada.

When it comes to plant-based proteins, “quinoa is pretty awesome because it has all nine essential amino acids,” says Smith. “And don’t forget about soy products like tofu, tempeh, and edamame — they’re complete proteins, too.”

Vitamin B-12: Since vitamin B-12 is found strictly in animal products, vegans will need to take extra precautions to guard against deficiency. “It is recommended for vegans to supplement in vitamin B-12 or include in the diet nutritional yeast, which contains all B vitamins, including vitamin B-12,” Abada says.

Omega-3 fatty acids: Good sources of plant-based omega-3s include chia seeds, walnuts, flaxseeds, seaweed, edamame, beans, tofu, spirulina, Brussels sprouts, rapeseed oil, spinach, and tofu, says Abada.

Calcium: “Milk and dairy foods are highest in calcium. However, dark green vegetables, such as turnip greens, spinach, mustard greens, collard greens, kale, and broccoli, are great sources. Almonds, edamame, and tofu are also good sources,” says Abada.

Vitamin D: According to the Harvard T.H. Chan School of Public Health, “the best sources [of vitamin D] are the flesh of fatty fish and fish liver oils. Smaller amounts are found in egg yolks [and] cheese.” While you can also find some foods that are fortified with the vitamin, such as certain plant-based milks, “the best way to get enough vitamin D is taking a supplement because it is hard to eat enough through food.”

Iodine: Abada says that fish and seafood are good sources of iodine, as are dairy products. For vegans, a great source of iodine is seaweed.

Zinc: For pescatarians, fish is a great source of zinc, and for lacto-ovo vegetarians, yogurt and cheese are notable sources. While plant-based zinc is not easily absorbed, it can be found in whole grains, legumes, and nuts, says Abada. Hever explains that “zinc is a mineral that’s plentiful in plants, but because of compounds called phytates, it inhibits the absorption of the zinc. We need to be considerate of either taking in more zinc or consider supplementing.”

Iron: Since plant-based iron is not easily absorbed, it’s a good idea to pair these foods with fruits and vegetables that are high in vitamin C, such as tomatoes, cabbage, broccoli, citrus fruit, kiwi, and more. “Iron can be found in legumes, whole grains, enriched cereals, dark leafy greens, peas, and dried fruit,” says Abada. You can also drink a small glass of water with lemon when eating iron-rich foods, she adds.

What to Avoid

Since not all plant-based foods are created equal, there are certain foods you’ll want to limit. For instance, there are vegetarian foods that aren’t health promoting, like ice cream, cakes, cookies, and french fries, says Geiger.

Overall, “it’s a good idea to limit processed foods that are high in oils and sugars,” says Hever. While these foods are undeniably tasty, you’re not going to get the health benefits that you see with a more wholesome plant-based diet, she says. Plus, diets high in processed foods and sugars lead to a higher risk of developing obstructive sleep apnea, which is associated with complications such as high blood pressure, cardiovascular problems, and increased waist circumference, according to the Mayo Clinic.

The quantity of certain foods matters, too. “For those who choose to consume eggs and dairy products, being mindful of the daily quantity one eats is important. These foods are high in fats — mostly saturated fats and cholesterol,” Abada says.

Tips to Get Started on the Vegetarian Diet

Start small. You don’t have to commit to going fully plant-based overnight, suggests Geiger. “You can make small changes every week or every other week until you get to a place that feels sustainable and doable for the long term. Remember, slow and steady won the race.”

Make easy substitutions. “Substitute meat or poultry in your favorite recipes with a plant-based protein such as tofu, beans, chickpeas, or lentils,” says Abada. For example, you can add baked or grilled tofu to sandwiches or wraps instead of the typical chicken or meat, she suggests.

Balance your plate. According to Abada, you should aim to fill your plate with half vegetables, including small quantities of starchy vegetables; one quarter protein; and one quarter whole grains, such as quinoa, barley, or amaranth. Between meals, enjoy one to two servings of fruit and about a quarter cup of nuts and seeds.

Make your own tasty treats. To ensure you’re controlling what goes into your food, consider making your own grab-and-go snacks, says Abada. This reduces the temptation to grab a potentially less-than-nutritious prepackaged treat.

Check the label. If you’re in a time crunch and find yourself reaching for a prepackaged snack or meal, pay attention to the label and make sure you’re fueling your body with the most natural foods possible, and with the least added sugars and saturated fats possible, says Abada.

Play with flavors. The sky’s the limit when it comes to exploring your meal options. “You can get absolutely wonderful sources of nutrition from vegetables, fruits, whole grains, legumes, mushrooms, nuts, seeds, herbs, and spices in infinite tasty combinations,” says Hever.

Get inspired. Unsure where to start? Visit your local vegetarian restaurant for inspiration, suggests Abada. You can also take a stroll through a nearby farmers market to see what scrumptious fruits and vegetables are in season.

Indulge with intention. For an eating plan that’s sustainable — and reasonable — you can build in having your favorite foods guilt-free. “If you’re eating healthy overall, you can allow the occasional [higher-calorie, lower-nutrition foods],” says Hever. “As long as you stay focused and mindful of what you’re eating, you can’t really ruin your progress.”

The Bottom Line

A well-planned vegetarian diet has the potential to offer significant health benefits ranging from a reduction in chronic diseases to improved weight management. If you’re thinking of making the switch to vegetarianism, consider working with a dietitian to form an eating plan that works best for you. It’s also a good idea to consult your doctor before beginning any supplementation or making dietary changes, especially if you have any pre-existing health conditions.

Additionally, you’ll want to schedule yearly health checkups, since lab work can identify any deficiencies in essential nutrients.

Last but not least, have fun with it. “Play with flavors and new cuisines. There are so many delicious plant-based foods, so don’t be afraid to try something new,” Geiger says.

Hever adds, “The best advice I have is to go for the most whole foods possible. Eat the rainbow every day, keep it simple, and find new foods that you love. It should be a fun journey.”

Tiffany Lin