A plant-based diet consists of mostly whole grains, fresh fruits and vegetables, legumes (pulses), unsalted nuts, and healthy oils such as olive oil or canola oil. Meat, fish, poultry, and other animal products are included but eaten less often and only in small portions. A vegetarian diet eliminates meat, fish, or poultry or any foods that contain animal protein. It includes whole grains, legumes (pulses), nuts, seeds, vegetables and fruits with or without the use of dairy products and eggs.

There are several different types of a vegetarian diet:

  • Semi-vegetarian: Does not eat red meat(s), but occasionally eats fish or poultry and dairy products. Semi-vegetarians are often people who are making a transition to a vegetarian diet.
  • Lacto-ovo vegetarian: Eats milk, dairy products and eggs but not meat, fish or poultry.
  • Lacto-vegetarian: Eats milk and other dairy products but not meat, fish, poultry or eggs.
  • Pescetarian: Eats a diet of fruits, vegetables, grains, legumes and includes fish. They may or may not eat eggs and dairy
  • Vegan: Do not eat any animal products (meat, fish, poultry, eggs or dairy foods). A vegan eats only plant-based foods.
  • Raw vegans: Eats only plant foods; including vegetables, fruit, nuts and seeds, legumes (dried beans, peas, and lentils), and sprouted grains. The majority of the food is uncooked varying from 75% to 100%.

What are the health benefits?

There are many reasons why people choose to follow a vegetarian or a plant-based diet, including financial reasons, ethical, environmental concerns and religious beliefs. Some people make the change for health reasons, as well. Vegetarian and plant-based eating may help reduce the risk of:

  • Cancer
  • Diabetes
  • Heart disease
  • High blood pressure
  • Kidney disease
  • Obesity

Can people with diabetes follow a vegetarian or plant-based diet(s)?

Yes. They can be higher in carbohydrates and lower in protein than meat-based diets, so glucose levels may be affected. As a result, your healthcare provider may need to change the amount or type of your diabetes medicine. Anyone interested in changing to

vegetarian or plant-based eating, including people with diabetes, should work with a dietitian to make sure they are meeting their nutritional needs.

Is vegetarian/plant-based eating nutritionally adequate?

A well-planned vegetarian/plant-based diet can be healthful and nutritionally adequate. Keep in mind that the more restricted the diet, the greater the chance of a nutritional deficiency. Below are some considerations.


Vegetarian/plant-based diet(s) can provide an adequate amount of protein as long as you eat a variety of foods and consume adequate protein sources. Protein is made up of amino acids, nine of which are called essential amino acids. Animal foods contain all of the essential amino acids, whereas plant foods are missing one or two. However, if you eat a variety of plant foods, you will get all nine essential amino acids.

Sources of Plant Protein

Legumes (Pulses)

Legumes include dry beans, peas, and lentils. They are an excellent food to extend or replace meat. Legumes are low cost, high in nutritive value, and contribute iron, B vitamins, and fiber to your diet. They are not a complete protein, because they do not contain all of the essential amino acids the body needs. When combined with a variety of other plant-based foods throughout the week, legumes can become valuable protein sources in your diet. Legumes may be purchased dry or canned. Dry legumes tend to be less expensive

Dry beans: Rich in protein, iron, calcium, phosphorus and potassium. There are many varieties of dry beans including black beans, garbanzo beans (also called chickpeas), kidney beans, lima beans, navy beans and pinto beans.

Dry peas: Good sources of protein, iron, potassium and thiamin. They are green or yellow and can be purchased split or whole.

Lentils: They are rich in protein, iron, potassium, calcium and phosphorus. They are small disc-shaped legumes; they can be brown, yellow or red.

Soy Products: Soy products include tofu, soymilk, tempeh and other products. They are derived from soybeans, a rich source of plant-based protein. Protein in soybeans contains as much complete protein as meat and are a good source of B vitamins and essential fatty acids, including some omega-3s. Soy foods are typically low in unhealthy fats (saturated/trans) and are cholesterol-free. They also contain isoflavones which may help lower the risk of some chronic diseases.

Soybean: A legume, which is an excellent, inexpensive source of protein and iron. Soybeans can be eaten in their whole form and, but are also used to make a number of vegetarian substitutions for meat, dairy, and eggs.

Soy cheese: A cheese-like product made from soybeans. They come in a variety of flavors such as parmesan, mozzarella and cheddar. Not all soy cheeses are vegan; some contain the milk protein casein.

Soymilk: A milk-like product made from soybeans, with a similar amount of protein and less fat than cow’s milk. Not all soymilks are vegan as some contain the milk protein casein. Fortified soymilks have calcium and vitamin D added.

Tempeh: Made from fermented soybeans and other grains, tempeh is a replacement for meat.

Textured Soy Protein (TSP): Commonly used as a substitute for ground beef; TSP is derived from soy flour.

Tofu: Made from curdled soymilk and pressed into blocks. It can be used as a replacement for meat, eggs and cheese and can be eaten fresh or cooked in many different ways. Tofu is an excellent source of protein. Types and suggestions of how to use tofu:

  • Extra-firm tofu: frying, roasting, grilling or marinating
  • Firm tofu: stir-frying, boiling or use as a filling
  • Soft tofu: pureeing
  • Silken tofu: pureeing, simmering, egg substitution, used in vegan desserts and smoothies

Nuts and Seeds

Nuts and seeds are some of the best plant sources of protein. They are rich in fiber, folic acid, potassium, antioxidants (vitamin E and selenium) and phytochemicals as well. Nuts are high in monounsaturated and polyunsaturated fatty acids, including omega 3 fatty acids. Because nuts and seeds are high in fat, portions should be limited.

Tree nuts: Includes almonds, Brazil nuts, cashews, hazelnuts, macadamias, pecans, pine nuts, pistachios and walnuts.

Seeds: Includes pumpkin, sesame, sunflower, chia and flaxseed.

Nut Butters: Peanut butter is the most popular but other nuts and seeds make butter: sunflower, almond, cashew, hazelnut and soy.

Omega-3 Fatty Acids
Research shows the many benefits of omega-3 fatty acids. They may reduce the risk for cardiovascular disease, improve cognitive function and vision, and act as an anti-inflammatory agent in the body. The primary sources of omega-3 fatty acids in the diet are fish, organ meats, and DHA-enriched foods such as eggs. Based on these food sources, vegetarians may not get enough omega-3 fatty acids in their diet. Adding some plant-based omega-3 rich foods can help the vegetarian meets their needs.

Sources of Omega-3 foods:

  • Flaxseed
  • Chia seeds
  • Hemp seeds
  • Walnuts
  • Canola oil
  • Soy
  • Some soymilks and breakfast bars



Plant foods contain a different form of iron than animal foods, called non-heme iron. Non-heme iron is not as well absorbed as heme iron. Non-heme iron will be better absorbed if eaten along with foods that contain vitamin C, or by cooking foods in cast-iron pots and pans. The daily recommendation for iron intake is 1.8 times higher for vegetarians than those who eat meat. For most vegetarians, an iron supplement is recommended to help meet iron requirements.

Sources of iron:

Bran flakes cereal Pumpkin seeds Instant oatmeal Dried beans/peas Fortified cereals Tofu

Sea vegetables Textured vegetable protein

Sources of vitamin C:

Cantaloupe Strawberries

Honeydew melon Broccoli

Citrus fruits Green peppers

Kiwi Tomatoes

Papaya Brussels sprouts


As with iron, zinc is a mineral that is present in plant foods but better absorbed from animal sources. As a result, some vegetarians can have lower concentrations of zinc than non-vegetarian diets. Most vegetarians still have levels within the normal range. True zinc deficiencies are rare in Western civilizations. Including foods rich in zinc can help the vegetarian maintain adequate levels of zinc in their body. Like iron, zinc can be better absorbed when eaten in combination with vitamin C-rich foods. (See list above)

Sources of Zinc:






Vitamin B-12

Vitamin B-12 is found mainly in animal foods. Some plant foods contain vitamin B-12, but not in a usable form. A lacto-ovo or lacto-vegetarian diet will provide adequate amounts of vitamin B-12. Certain foods are fortified with vitamin B-12, such as some breakfast cereals, soymilk and meat substitutes. If you are a vegan, you must either make sure you eat these fortified foods, or take a B-12 supplement.

Sources of Vitamin B-12:

Fortified cereals Eggs

Brewer’s yeast Milk and milk products

Fortified meat substitutes Fortified soy milk


A lacto-ovo vegetarian diet generally is adequate in calcium. A vegan diet tends to provide lower amounts of calcium, although, with careful planning, a vegan diet can supply enough calcium. Your dietitian may recommend a calcium supplement if you can’t meet your calcium needs through food sources.

Note: Calcium decreases the absorption of iron. If taking supplemental calcium or iron, take them at separate times of the day.

Sources of calcium:

Milk and milk products Legumes

Fortified soy milk Collard greens

Tofu (made with calcium) Turnip greens

Fortified orange juice Kale

Vitamin D

Vegan diets may be low in vitamin D, since cow’s milk is the most common source of this vitamin. However, if you follow a vegan diet, you can get enough vitamin D from fortified cereals and fortified milk alternatives. Unprotected exposure to sunlight (hands and arms) for 15-20 minutes a day can also supply adequate vitamin D. Some people may need a vitamin D supplement. Your dietitian may recommend supplemental vitamin D if your diet is deficient and/or your vitamin D level is low.

Sources of vitamin D:

Fortified cereals Fortified soy milk

Milk Sunlight

Getting started with vegetarian/plant-based meal planning

  • Choose a variety of foods, including whole grains, vegetables, fruits, legumes, nuts, seeds, and, if desired, dairy products and eggs.
  • Try gradually decreasing the amount of animal protein to allow time to adjust to a vegetarian/plant-based diet.
  • Substitute soy products (tofu, meat substitutes) and legumes for meat, poultry and fish.
  • If you use milk products and eggs, choose lower-fat versions of these foods, such as skim or 1% milk and yogurt, and egg whites or egg substitutes.
  • If you are following a vegan diet, be sure to include a regular source of vitamin B-12 in your diet along with a source of vitamin D if sun exposure is limited. Supplements are often required to meet nutrient needs.
  • Use fats sparingly; choose unsaturated fats, such as olive, canola and peanut oils, nuts and seeds, instead of saturated fats, such as butter, margarine and cream cheese.
  • Limit your intake of high-fat foods, such as cheeses, whole milk, nuts, seeds, avocados and oils, especially if you are trying to lose weight.
  • Be sure to count the carbohydrates in foods – many vegetarian diets can be very high in carbohydrates. Keep your carbohydrate intake consistent and read food labels carefully for their carbohydrate content.
  • It is important to monitor your glucose regularly if you are changing to a vegetarian diet/plant-based diet. Your diabetes medication or insulin dose may need to be adjusted, especially if you are eating more carbohydrates than before.

Vegetarian meal ideas

Below are some meal ideas to help get you started? Again, be sure to include a variety of foods in your eating plan.

Breakfast: Whole-grain cereal and skim/1% fat or milk alternatives; whole-grain toast; bagels; English muffins; pancakes and waffles; fruit; eggs and egg substitutes; nonfat Greek yogurt; regular/low-fat cheeses; peanut and nut butter; tofu “cream cheese”; vegetarian/plant-based proteins “bacon” and “sausage”.

Lunch/Supper: grilled cheese sandwich; hummus and vegetable sandwich; peanut butter and jelly sandwich; minestrone, bean, split pea and lentil soups; vegetable pizza; rice and beans; bean and vegetable burritos bowls; macaroni and cheese; vegetarian lasagna; stir-fry vegetables and tofu; “veggie/plant-based” burgers; vegetarian-style chili

Note: Many vegetarian and planted-based frozen products are not necessarily healthy choices. Some of the products can be high in calories and fat. Always read the nutrition facts to make sure the item is appropriate for your goals. 


Vegetarian Society - https://www.vegsoc.org
The Vegetarian Resource Group - https://www.vrg.org/
Eating Vegetarian - https://www.nutrition.gov/topics/basic-nutrition/eating-vegetarian
Vegetarian Times - https://www.vegetariantimes.com
Mark Bittman - https://www.markbittman.com/
PBS, Jazzy Vegetarian Cooking Show - http://www.pbs.org/food/shows/jazzy-vegetarian/
Forks over Knives - https://www.forksoverknives.com/
The Plant-Based Network - https://plantbasednetwork.com

Although this content is reviewed by Joslin Diabetes Center healthcare professionals, it is not intended to replace the medical advice of your doctor or healthcare provider. Please consult your healthcare provider for advice about a specific medical condition.