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The question

My teenage daughter wants to become a vegan. Is it safe?

The answer

It's only natural to worry if your vegetarian daughter will get the nutrients she needs. Depending on the type of vegetarian diet she follows, there may be cause for concern. A number of studies show that vegetarian teens don't meet daily targets for calories, protein, calcium, iron and zinc.

A vegan diet is the strictest form of vegetarian as it avoids all animal foods: meat, poultry, fish, eggs and dairy products. Lacto-vegetarians do eat dairy products. Lacto-ovo-vegetarians include dairy and eggs in their diets. And pesco-vegetarians will eat fish, dairy products and eggs.

Here's the good news. A vegetarian diet – vegan diets included – can provide growing teenagers with all the nutrients their bodies need if it's properly planned.

Even so, it's important to keep a watchful eye. Research has shown that some girls use a vegetarian diet as a way to hide an eating disorder.

The keys to a nutritionally complete vegan diet are planning and variety. Encourage your daughter to learn more about vegetarianism. If possible, I recommend she consult with a dietitian to learn how to balance a vegan diet. Here are a few tips to get her started.

Protein. Vegans get protein from lentils, beans (e.g. chickpeas, kidney beans, black beans, soy beans), tofu, tempeh, seitan (a protein made from wheat), soy beverages, nuts and seeds. Whole grains and vegetables also supply some protein. Rice, almond and oat beverages are low in protein.

Vitamin B12. Naturally occurring only in animal foods, vegans need to include three servings of B12 in their daily diet. One serving equals: fortified plant beverages (1/2 cup), nutritional yeast (1 tablespoon), fortified breakfast cereal (30 grams) or fortified soy products (42 grams).

To ensure B12 needs are met, take a B12 supplement or multivitamin with 5 to 10 micrograms of B12.

Calcium. This mineral is vital for building strong bones and teeth. Because most peak bone mass is achieved by age 18, teenagers have high daily calcium requirements (1,300 milligrams). Getting too little calcium during the teen years can increase the risk for osteoporosis later in life.

Good food sources in a vegan include fortified plant beverages and juice, tofu made with calcium sulphate, beans, cooked green leafy vegetables (kale, collards, Swiss chard, spinach), cooked broccoli, almonds, tahini, and blackstrap molasses.

To meet daily calcium requirements, a supplement may be required.

Iron. This nutrient is especially important for teenage girls who need more of the mineral than boys because of menstruation. Since vegetarian iron sources are not as easily absorbed as animal sources, vegetarians have higher daily iron requirements than meat-eaters.

Food sources include beans, lentils, nuts, leafy green vegetables, whole grains, breakfast cereals and dried fruit. Iron absorption can be increased by eating plant foods with vitamin C-rich foods such as citrus fruit, strawberries, red pepper and tomato juice.

Leslie Beck, a registered dietitian, is based at the Medisys clinic in Toronto. She can be seen every Thursday at noon on CTV News Channel's Direct (

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