A lacto-ovo-vegetarian diet can benefit your health in a number of ways, including improving your heart health, supporting weight loss, and reducing cancer risk.

A lacto-ovo-vegetarian diet is a primarily plant-based diet that excludes meat, fish, and poultry but includes dairy and eggs.

In the name, “lacto” refers to dairy products, while “ovo” refers to eggs.

Many people adopt a lacto-ovo-vegetarian diet to reduce their intake of animal products for ethical, environmental, or health reasons.

This article explains the benefits and downsides of a lacto-ovo-vegetarian diet and provides lists of foods to eat and avoid, as well as a sample meal plan.

Research shows that a well-planned and balanced lacto-ovo-vegetarian diet can benefit your health in a number of ways.

May help prevent type 2 diabetes

Lacto-ovo vegetarians have a lower risk of developing type 2 diabetes. That said, while eating meat is associated with a higher risk of type 2 diabetes, the protective effects of vegetarian diets may be unrelated to a lack of meat (1, 2, 3, 4).

Vegetarian diets lower your risk of type 2 diabetes by increasing your intake of healthy foods, such as whole grains, fruits, vegetables, legumes, and nuts, and decreasing your intake of saturated- and trans fats (1, 5, 6, 7).

What’s more, they have been shown to increase blood sugar control and improve sensitivity to insulin, a hormone that regulates your blood sugar levels (8, 9, 10).

Additionally, plant-based diets are high in fiber, which slows digestion and improves blood sugar control. Vegetarian diets have also been shown to decrease hemoglobin A1c, a marker of long-term blood sugar control (6, 7).

Can support healthy weight loss

Lacto-ovo-vegetarian diets can help you maintain a healthy weight or support weight loss.

Vegetarian diets are typically high in fiber and low in calories, which may support feelings of fullness and prevent overeating.

In fact, research shows that vegetarian diets help prevent and reverse obesity and obesity-related diseases (11, 12).

A study in nearly 38,000 people found that vegetarians had a lower body mass index (BMI) than omnivores. A higher BMI was associated with high protein and low fiber intakes, indicating that plant-based diets high in fiber may benefit weight loss (13).

Improves heart health

Eating meat, certain types of fat, and refined carbs has long been associated with atherosclerosis, which is the buildup of plaque in your arteries that can lead to heart disease (14, 15).

A vegetarian diet has been shown to lower your risk of — and even reverse — coronary artery disease. This is especially true when animal foods are limited, as is the case when you follow a lacto-ovo-vegetarian diet (16).

Plant-based diets have been shown to improve blood flow to your heart, improve blood vessel health, and reduce blood pressure — all of which may reduce heart disease risk (17, 18, 19, 20).

May reduce cancer risk

Vegetarian diets have been associated with a reduced risk of various cancers. A review of 96 studies found that vegetarians had an 8% lower risk of death from cancer compared with omnivores (21, 22).

Research shows that your cancer risk can be significantly reduced by eating a diet rich in plant foods like fruits and vegetables. Plus, some research suggests that diets high in red- and processed meat can increase your risk of certain cancers (23, 24, 25).

May lower gallstone risk

Lacto-ovo vegetarians have a lower risk of gallstone disease, a condition in which hard, stone-like pieces of cholesterol or bilirubin form in your gallbladder, block your bile duct, and cause pain.

A 6-year study in 4,839 people found that non-vegetarians had a 3.8 times higher risk of developing gallstone disease than vegetarians. This may be due to the lower cholesterol intake of those on vegetarian diets (26).

Summary

Following a lacto-ovo-vegetarian diet may support healthy weight loss, benefit your heart health, and lower your risk of certain cancers, type 2 diabetes, and gallstones.

Although a vegetarian diet offers many health benefits, proper planning is essential to prevent adverse health effects.

Below are some factors to consider when adopting a lacto-ovo-vegetarian diet.

The potential need for supplements

A vegetarian diet can be nutritionally adequate, but extra attention should be paid to your intakes of iron, protein, zinc, and omega-3 fatty acids. Dietary supplements may be recommended if food sources of these nutrients are lacking (27, 28).

Protein is essential for good health. Vegetarian sources include eggs, dairy, beans, peas, lentils, tofu, grains, nuts, and seeds. Foods rich in the amino acid lysine — a building block of protein often lacking in plant-based diets — include legumes, nuts, seeds, and eggs (29).

Iron transports oxygen in your body. Vegetarians may need 1.8 times more iron than omnivores. Vegetarian iron sources include tofu, beans, lentils, fortified grains, almonds, and greens. Vitamin-C-rich foods, such as citrus and peppers, can boost absorption (30, 31).

Zinc supports growth, wound healing, and a healthy immune system. Some plant-based, zinc-rich foods include beans, peas, lentils, tofu, peanut butter, cashews, grains, and fortified cereals.

Omega-3 fatty acids include EPA, DHA, and ALA (a precursor to EPA and DHA). They support heart, eye, skin, nerve, and brain health. Taking an algal oil supplement and eating foods like walnuts and flax can help you meet your omega-3 needs (32).

Importance of diet quality

With the growing popularity of plant-based diets, there are many vegetarian-friendly foods from which you can choose.

However, many foods marketed for lacto-ovo vegetarians are prepackaged and highly processed, meaning they can be high in added sugar, salt, unhealthy fats and oils, and calories.

Be sure to look at the ingredient list and nutrition label to decide whether these foods are right for you.

Summary

Lacto-ovo-vegetarian diets should be properly planned to meet your nutrient needs, especially for protein, zinc, iron, and omega-3 fats. Be sure to review the ingredient list and nutrition label to see if packaged vegetarian foods suit your health goals.

Those following a lacto-ovo-vegetarian diet avoid animal-derived foods, except for eggs and dairy products.

You must look at the ingredient label of any packaged food to determine if it contains animal-based ingredients, including:

  • Meat: beef, veal, lamb, pork, and processed meats like sausage, bacon, and hot dogs
  • Fish: fish, shellfish like crab and lobster, other seafood like shrimp
  • Poultry: chicken, duck, goose, quail, turkey
Summary

A lacto-ovo-vegetarian diet excludes meat, fish, and poultry.

Base your diet on whole, unprocessed plant foods, as well as egg and dairy products, including:

  • Fruits: apples, bananas, oranges, strawberries, peaches, melons
  • Vegetables: broccoli, kale, bell pepper, spinach, mushrooms, eggplant
  • Whole grains: quinoa, barley, amaranth, oats, buckwheat
  • Eggs: whole eggs, including whites and yolks
  • Dairy products: milk, yogurt, cheese, butter
  • Beans and legumes: beans, peas, peanuts, lentils
  • Nuts, seeds, and nut butters: cashews, almonds, walnuts, pumpkin seeds, flax seeds, peanut butter
  • Healthy fats: avocados, olive oil, olives, nuts, seeds
  • Vegetarian protein: tofu, seitan, tempeh, and vegetarian protein powder
Summary

Eat whole, minimally processed plant foods, including fruits, vegetables, nuts, seeds, and whole grains, as much as possible. Also, include eggs and dairy products, such as milk, cheese, and butter, as you like.

Here’s a 5-day meal plan to get you started on a lacto-ovo-vegetarian diet. Adjust it to fit your tastes and preferences.

Monday

  • Breakfast: scrambled eggs with vegetables and buttered toast
  • Lunch: mixed green salad with tofu drizzled with olive oil and vinegar, served with a handful of nuts and raisins
  • Dinner: veggie cheeseburger with lettuce, tomato, and onion on a bun, served with a side of roasted asparagus

Tuesday

  • Breakfast: fruit and yogurt smoothie with a hard-boiled egg
  • Lunch: pasta salad with beans, cheese, and vegetables, served with a side of grapes
  • Dinner: seitan and vegetable stir-fry with a side of berries

Wednesday

  • Breakfast: oatmeal with apples and cottage cheese
  • Lunch: tempeh and vegetable wrap, served with carrots and hummus
  • Dinner: grilled cheese and tomato soup, served with roasted vegetables

Thursday

  • Breakfast: spinach quiche and fruit
  • Lunch: veggie and cheese pizza on a tortilla
  • Dinner: lentil loaf with roasted potatoes

Friday

  • Breakfast: avocado and hummus toast and a banana
  • Lunch: chickpea salad sandwich with vegetable soup
  • Dinner: nachos with “the works,” including beans, cheese, ground soy, sour cream, salsa, avocado, and black olives, served with a side of fruit

Simple snack ideas

Here are some easy, lacto-ovo-vegetarian snack ideas if you get hungry between meals:

  • hard-boiled eggs
  • trail mix made with nuts, seeds, and dried fruit
  • banana slices with almond butter
  • raw vegetable sticks with hummus
  • yogurt with berries and seeds
  • roasted chickpeas
  • whole-grain crackers with guacamole
  • popcorn with Parmesan cheese
  • celery with peanut butter and raisins
Summary

You can make many healthy and delicious meals and snacks using vegetarian foods. The sample menu above shows you what five days on a lacto-ovo vegetarian diet might look like, plus a few snack ideas to enjoy between meals.

A lacto-ovo-vegetarian diet is suitable if you’re interested in reducing your intake of animal products but not completely eliminating them from your diet.

This diet has been linked to several potential health benefits, including a reduced risk of obesity, heart disease, type 2 diabetes, and certain cancers.

Eating a lacto-ovo-vegetarian diet can help you eat more whole, unprocessed plant foods, to which many of the health benefits associated with this way of eating are attributed.

Be sure to pay attention to your nutrient intake and read the labels on packaged vegetarian foods to ensure that your diet is aligned with your health goals and nutrition needs.