Vegetarian and Vegan Diet

  • Author:
    Betty Kovacs, MS, RD

    Betty is a Registered Dietitian who earned her B.S. degree in Food and Nutrition from Marymount College of Fordham University and her M.S. degree in Clinical Nutrition from New York University. She is the Co-Director and Director of nutrition for the New York Obesity Research Center Weight Loss Program.

  • Medical Editor: Melissa Conrad Stöppler, MD
    Melissa Conrad Stöppler, MD

    Melissa Conrad Stöppler, MD

    Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

Quick GuideVegetarian Diet: Becoming a Vegetarian

Vegetarian Diet: Becoming a Vegetarian

Iron

Iron is essential for health and transporting oxygen. A deficiency in iron causes fatigue and decreased immune function. There are two forms of dietary iron: heme and nonheme. Heme iron is found in animal foods, while nonheme iron is in plant foods.

The amount of iron that the body obtains and uses from the food is referred to as iron absorption. The iron absorption from heme iron ranges from 15%-35% while the absorption from nonheme iron is only 2%-20%. Evidence does not show any greater iron deficiency anemia in vegetarians than in omnivores, but body iron stores in vegetarians do tend to be lower so it's important to pay attention to your intake. There are ways to increase the absorption of nonheme iron and meet your recommendations:

  • Consuming vitamin C (citrus fruits, juice, red peppers) at the same time that you consume foods with nonheme iron will increase iron absorption.
  • Consuming meat protein at the same time that you consume nonheme iron foods increases iron absorption.
  • Calcium, tannins, and phytates interfere with the absorption of iron. Tannins are found in tea and coffee. Phytates are found in whole grains and legumes. Take any supplements containing calcium and foods containing calcium, tannins, or phytates separately from the time you consume iron-rich foods or an iron supplement.
  • When you need a supplement, you want one with ferrous iron salts (ferrous fumarate, ferrous sulfate, and ferrous gluconate). The amount of iron that you absorb decreases with increasing doses, so it's best to spread your supplements out over the day. Iron can be toxic at high levels, so do not supplement if you do not need to and consult with your physician before taking a supplement.
  • Have your iron levels checked by your physician.
Nutrient Function Non-Vegan Sources Vegan Sources
Vitamin B12 Producing and maintaining new cells; helps make DNA; helps maintain the nervous system
  • Mollusks, clams
  • Beef liver
  • Trout
  • Salmon
  • Beef
  • Yogurt
  • Haddock
  • Tuna
  • Milk
  • Eggs
Fortified foods:
  • Breakfast cereals
  • Vegetable stock
  • Vegetable and sunflower margarines
  • Veggie burgers
  • Textured vegetable protein
  • Yeast extracts
  • Soy milk
Calcium Strong bones; contract and expand blood vessels and muscles; send message to nervous system; secrete hormones and enzyme
  • Milk
  • Cheese
  • Cottage cheese
  • Salmon w/bones
  • Sardines w/bones
  • Yogurt
  • Fortified soy milk
  • Fortified juice
  • Tofu-made w/calcium sulfate
  • Soybeans
  • Soy nuts
  • Bok choy
  • Kale
  • Mustard greens
  • Blackstrap molasses
Iron Transport oxygen; regulation of cell growth and differentiation; integral part of many proteins and enzymes Heme iron:
  • Chicken liver
  • Oysters
  • Beef
  • Clams
  • Turkey
  • Chicken
  • Tuna
Non-heme iron:
  • Chickpeas
  • Lentils
  • Beans
  • Fortified cereal
  • Fortified oatmeal
  • Tofu
  • Wheat
Vitamin D Decreased incidence and severity of cardiovascular disease; lowering of blood pressure in hypertension; prevention and treatment of depression; decreased risk of type 2 diabetes; prevention of osteoporosis and osteopenia; decreased inflammation; decreased dental cavities; reduced risk of allergies in children and adolescents; decreased mortality from various forms of cancer; decreased incidence of rickets; possible decrease in erectile dysfunction; and regulation of blood cholesterol
  • Sunlight
  • Cod liver oil
  • Salmon
  • Sardines
  • Mackerel
  • Tuna
  • Egg yolk
  • Fortified milk
  • Sunlight
  • Shiitake mushrooms
  • Fortified orange juice
  • Supplements
Omega-3 Fatty Acids Protect against atherosclerosis; reduce triglyceride levels; act as an anti-inflammatory; possibly help with depression and other personality disorders; and possibly thin the blood Fatty fish:
  • Anchovies
  • Bluefish
  • Carp
  • Catfish
  • Halibut
  • Herring
  • Lake trout
  • Mackerel
  • Pompano
  • Salmon
  • Striped sea bass
  • Whitefish
  • White tuna (Albacore)
Source EPA & DHA:
Microalgae oil

Source EPA:
  • Flaxseed oil
  • Flaxseeds
  • Rapeseed
Medically Reviewed by a Doctor on 4/8/2015

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