The vegan diet for infants and children

35^th World Vegetarian Congress
'Food for all our futures'
Heriot Watt University, Edinburgh, Scotland
July 8-14, 2002

by Sandra Hood, BSc (Hons), SRD
(with acknowledgement to input by Reed Mangels PhD)

[ Vai alla traduzione in italiano ]

If you go to a gathering of vegans, you may notice the children. They often provide glowing testimony to the fact that vegan children can be healthy, grow normally, be extremely active, and (we think) smarter than average. Of course it takes time and thought to feed vegan infants and children. Ideally, all parents, whether vegan or not, should be thinking carefully about what their children eat. The years from birth to adolescence are the years when eating habits are set, when growth rate is high, and to a large extent, when the size of stores of essential nutrients such as calcium and iron are determined.
In this lecture, I shall examine the health benefits of vegan diets for children, address potential concerns, present information on key nutrients, and provide guidelines for feeding vegan infants and children.
The number of vegans in the UK today is estimated at 0.5% (1) but we do not know how many of these are children. In the US, a poll in 2000 commissioned by The Vegetarian Resource G roup found that about 0.5% of 6 to 17 year olds are vegan - they do not eat meat, fish, poultry, dairy products or eggs (2). Meat consumption is falling in all socio-economic groups: 14% of 6 month old children never eat meat (Office of National Statistics 1995) and meat only provides about 0.5 mg iron in the daily diets of children aged 18-30 months which is less than 7% of the recommended intake of 6.9 mg per day (National Diet and Nutrition Survey. Children aged 1.5 to 4.5 years. Volume 1. Report of the diet and nutrition survey 1995 HMSO London) .

Health Benefits of Vegan Diets

Several studies have examined the nutrient intakes of vegan children. One study of British school-age children found that they had higher intakes of fibre and that intakes of all vitamins and minerals studied (with the exception of calcium) compared to those of meat-eating children (3).

I detail below the most recent study on the dietary intakes of vegan children compared to children on omnivorous diets.

As you will see, with the exception of vitamin B12 and calcium, the intake of essential nutrient s was similar or greater in the vegan children than those reared on mixed diets. Protein intake for the vegan and omnivorous children was the same.

This was only a small study and unfortunately no studies have been carried out since this one in 1992. However, Plamil foods since 1977 have produced case histories on over 100 children which are glowing testimony to the health of children brought up on a vegan diet.

Vegan preschoolers in the US were found to have generous intakes of protein, vitamins, and minerals; their diets exceeded recommended intakes for all nutrients studied, again with the exception of calcium (4). Although cow's milk provides about two-thirds of the calcium in the diets of omnivore preschool children, in many parts of the world cow's milk is not consumed and calcium intakes are low. It is not surprising, therefore, that the vegan children had low intakes. However no estimate was made of the calcium provided by drinking water; in hard water areas this amounts to as much as 250 mg/day. Moreover, adaptation to low calcium intakes is well known to occur (24) and it was showed (25) that children receiving as little as 200 mg/day remained in positive calcium balance.

The study showing lower calcium intakes by vegan preschoolers was conducted before calcium-fortified products were readily available so calcium intakes of vegan children may be higher now. Calcium is important for bone development. Around 45% of adult bone mass is accrued before 8 years of age, another 45% is added between 8-16 years of age and a further 10% accumulates in the next decade. Given the importance of calcium intake during childhood, all parents should ensure that their children's diets contain calcium rich foods and meet current recommendations for calcium for their age group.

Regrettably, there have been few recent studies looking at the long-term effects of a vegan diet, especially as it is believed that the foundations for many chronic diseases of adulthood have their beginnings in childhood. For example processes initiating atherosclerosis and high blood pressure are thought to start very early in life and blood pressure and cholesterol levels have been shown to track from early childhood and to be related to childhood nutrient intakes (5, 6). Body mass intake tracks from early childhood with obese children being at an increased risk of obesity in adulthood (7). One in 10 children in Britain is overweight. In February this year for the first time, 4 white teenagers were diagnosed with adult type 2 diabetes, all 4 children were overweight.

A study in 2000 (Thane CW & Bates CJ Dietary intakes and nutrient status of vegetarian preschool children from a British national survey J Hum Nutr Dietet 13:3 pp149-162) looked at the diet of over 1.000 eighteen month olds and compared omnivores with vegetarians (no vegans were included). The study concluded that apart from lower levels of serum ferritin, indicating lower iron stores, the higher levels of anti-oxidants in the blood, lower fat and sodium intakes of the vegetarian pre-school children could be considered more desirable than the omnivorous children
When we look at potential long-term health benefits of vegan diets, we find that vegan children have higher intakes of fruits and vegetables, foods that are important for health. Vegan children have been shown to have lower intakes of fat, saturated fat, and cholesterol than non-vegetarian children (9, 10). This may be important in reducing the risk of developing chronic diseases like heart disease, obesity, and hypertension. Finally, vegan diets may introduce children to a greater variety of whole plant foods, thus establishing healthful lifelong eating habits.

Vegan Infants

Up to the age of four to six months, the diets of many infants of vegan parents and infants with non-vegan parents are identical. The perfe ct food for the young infant is breast milk and supplemental foods should not be introduced until after four to six months of age. Breast-fed infants of well-nourished vegan women tend to grow and develop normally (11). The infant receives many benefits from breast-feeding including some enhancement of the immune system, protection against infection, and reduced risk of allergies (12). In addition, human breast milk is the natural food for baby humans and quite probably contains substances needed by growing infants that are not even known to be essential and are not included in infant formulas. Nursing mothers also receive benefits including a reduced risk of premenopausal breast cancer, release of stress-relieving hormones, and, for some, convenience (12). For all these reasons, we strongly encourage breast-feeding.
Vitamin B12 and vitamin D are key nutrients for the young infant who is being exclusively breast-fed by a vegan woman. Vegan women, whose diets contain little or no vitamin B12, produce milk with very low levels of vitamin B12 (13). Since this vitamin is important for the developing nervous system, it is crucial for the infant to have a reliable source of vitamin B12. Many vegan women opt to use a vitamin B12 supplement or rely on fortified foods such as some breakfast cereals, fortified yeast extracts, vegan milks and some soya products to meet both their own vitamin B12 needs and the needs of their infant. If the mother's diet does not contain a daily, reliable source of vitamin B12, we recommend the young infant should receive a daily supplement of vitamin B12.

The vitamin D content of breast milk varies with the mother's diet and her sun exposure although vitamin D levels in breast milk are usually quite low. All children below 3 years of age have a high requirement for vitamin D to enable calcium deposition in bone. Therefore the Department of Health recommends that vitamin drops containing vitamins A, C and D be used by all children from 6 months to 5 years of age, whether vegan, vegetarian or omnivore. The welfare vitamin drops, which are available at low cost or free to certain families, contain no animal products and are suitable for vegans.
You may also have heard of DHA (docosahexaenoic acid), a fatty acid that appears to be important for eye and brain development. It is found primarily in animal foods. However, vegans can make DHA from another fatty acid called alpha-linolenic acid. Alpha-linolenic acid is found in breast milk if the mother's diet includes good sources such as flaxseed oil, ground flaxseed, rapeseed oil, and soya oil. If a mother is breast-feeding, she needs to reduce her use of other oils like corn oil, sunflower oil, and safflower oil and limiting foods containing hydrogenated fats can also help the infant to make more DHA. These oils contain linoleic acid and hydroge nated fats contain trans-fatty acids that interfere with DHA production.
If breast-feeding is not possible or is contraindicated there is only one formula feed suitable for vegan infants, Farley's Soya Formula by Heinz. On no account should you use soya milk, nut milk, rice milk, oat milk, pea milk or other home-prepared "formulas" because these do not contain the appropriate ratio of nutrients and can lead to potentially life-threatening conditions.

Introduction of Solid Foods

Solid foods should not be introduced before 4 months of age. Try to introduce one new food at a time, waiting 2 to 3 days before trying another food to see if the baby has a reaction to the food. This way, if a reaction does occur, it is easier to identify which food caused the reaction.
First weaning foods may include rice-based dishes, pureed and sieved fruits such as banana, pear and apple and vegetables, for example carrot, potato and spinach. At 6 months of age wheat and oat based cereals can be introduced. Foods containing generous amounts of protein, such as mashed, cooked pulses, mashed tofu, and soya yogurt are generally introduced at around 7 to 8 months of age. Children should progress from mashed or pureed foods to pieces of soft food. Smooth nut and seed butters spread on bread or crackers can be introduced after the first birthday. In an atopic family, where there is a history of allergies, peanuts and nuts should be avoided until the child is at least 3 years of age (14) to allow the gut to mature and the immune system to fully develop.
As solid foods become a larger part of the diet, consideration should be given to foods that provide concentrated sources of calories and nutrients. These include mashed firm tofu, bean spreads, mashed avocado, and cooked dried fruits. Frequent meals and snacks can help to ensure adequate energy intakes. The fat intake of healthy infants should not be restricted; sources of dietary fat such as vegetable oils or soft vegan margarine should be included in the older infant's diet.
Foods like whole nuts, nut butters, vegetarian hot dogs, large chunks of hard raw fruits and vegetables, whole grapes, hard sweets, and popcorn should not be fed to infants and children younger than 3 years to minimize the risk of choking. Practices like chopping nuts, slicing vegetarian hot dogs, and halving grapes can reduce the risk of choking and allow these foods to be eaten by toddlers age 1-3 years. Corn syrup and honey (commonly avoided by vegans) should not be given to infants younger than one year because of the risk of botulism, a form of food poisoning.

Many parents choose to use commercially prepared baby foods. There are products available that are suitable for vegan infants although careful label reading is recommended. Because there is only a limited selection of commercial products for the older vegan infant, many parents opt to prepare their own baby foods. Foods should be well washed, cooked thoroughly, and blended or mashed to an appropriate consistency. Home-prepared foods can be kept in the refrigerator for up to 2 days or frozen in small quantities for later use. It should be remembered that children's attitudes to food are very much affected by their parents attitudes. If Mum and Dad don't eat fruit and vegetables, we have poor role models.
By 6 months of age, iron stores in omnivorous, vegetarian and vegan infants will become depleted and it is important that iron rich foods are included in the diet. Iron-fortified infant cereals are a good way to supply iron to vegan infants Other good sources of iron include whole grains, pulses, green leafy vegetables, and dried fruits. To enhance iron absorption, add a source of vitamin C, such as green leafy vegetables, citrus fruits, blackcurrants, tomatoes and orange juice, to the meal.

Typically, for the non-vegan child, cow's milk is introduced around age 1 year. Commercial, fortified, vegan milks such as Plamil pea and soya milks can be added to the diet of vegan toddlers around the same age provided that the child is growing normally, has an appropriate weight and height for age, and is eating a variety of table foods including soya products, pulses, grains, fruits, and vegetables. For those children with slower growth who have been weaned from breast milk, ensure the diet is energy dense, and Farley's Soya Formula can be used in addition to vegan milks to provide extra energy, vitamins and minerals. Following introduction of fortified vegan milks, parents should continue to offer breast milk or commercial soya formula as a supplementary beverage until the child is at least 2 years old or is able to drink fortified vegan milk daily. Choosing unflavoured varieties of vegan milk in preference to flavoured varieties such as vanilla, cocoa, or carob can help to avoid a preference for very sweet beverages by the young child. The total fat content of most vegan milks, with the exception of Plamil, are similar to that of reduced fat cow's milk. Therefore other foods that provide fat should be added to the diet of vegan infants so that dietary fat is not overly restricted.

Vegan Toddlers and Preschoolers

Toddlers and preschoolers, whether vegan or not, tend to eat less than most parents think they should. This is generally due to a developing sense of independence and a slow-down in growth. While nutrient needs are also relatively lower than during infancy, an adequate diet remains important in order to promote growth and development. These early years are also important for developing healthy eating patterns that can establish a foundation for a healthful adult diet. Parents should offer a variety of foods and repeated exposure can result in acceptance.
One important consideration for young vegan children is their ability to get enough calories. Young children have small stomachs and eating a lot of high fibre foods may make them feel full before they have consumed all the calories that they need. A raw food or fruitarian diet is not suitable for children. Foods like avocados, nut and seed butters, dried fruits, and soya products can provide a concentrated source of calories. The fibre content of a vegan child's diet can be reduced, if necessary, by giving the child some refined grain products, fruit juices, and peeled fruits and vegetables. Eating more frequent meals, including nutritious snacks, can help to ensure adequate energy intakes.

Growth of Vegan Children

If a child's diet contains enough calories, we would expect to see normal growth and development. Studies of vegan children have shown that their caloric intake is close to recommended levels and similar to intakes of non-vegan children of the same age (16, 19).
Vegan children in the UK and the US have been found to be slightly shorter and lighter in weight than average but appeared to be growing at a normal rate (15, 16). Children need a lot of energy in relation to their size and although healthy eating should be encouraged, it is important that the diet be energy dense. Including foods such as vegetable oils, avocados, seeds, nut butters and pulses can provide both calories and nutrients. Dried fruits are also a concentrated source of energy and are an attractive food for many children. Children from an early age should be encouraged to brush teeth after eating dried fruits and other sweet foods to prevent tooth decay.

Key Nutrients for Vegan Children

PROTEIN
Protein needs can be easily met if children eat a variety of plant foods and have an adequate intake of calories. It is unnecessary to precisely plan and complement amino acids within each meal as long as children eat a variety of meals and snacks each day.

The protein in foods such as tofu, tvp, meat substitutes and refined grains is as digestible as that in animal products. However wholegrains and vegetables are slightly less digestible, around 85% digestible. So experts have suggested that a factor of 10-15% be added to cover differences in protein digestibility. Accordingly the protein needs for vegan children younger than 2 years is increased by 30-35%, those 2-6 years 20-30% children over 6 years 15-20%.

This provides an extra 2-11 g protein/day which can easily be met with an adequate calorie intake

Sources of protein for vegan children include pulses (peas, beans, lentils, soya), grains (wheat, oats, rice, barley, buckwheat, millet, pasta, bread), nuts, meat substitutes and nut butters.

CALCIUM
Limited data suggest that calcium intakes of vegan children are below current recommendations. Claims are commonly made that vegans require less calcium than omnivores based on the lower acid production resulting from metabolism of plant proteins (20, 21) This has not been resolved.

Although oxalates, phytates and fibre in plant foods decrease calcium availability, research shows that absorption of calcium from many plant foods is excellent. Calcium absorption from low oxalate vegetables such as broccoli and kale ranges from 52% to nearly 59% compared to 32% for milk (22) Calcium absorption from beans, nuts and seeds is lower.

Calcium is an important nutrient for growing bones and teeth. Good sources of calcium include fortified vegan milks and juices, calcium-set tofu; blackstrap molasses; baked beans; textured vegetable protein (TVP) and dark green leafy vegetables low in oxalic acid such as spring greens and kale. Calcium supplementation may be indicated in cases of inadequate dietary intake.

VITAMIN D
All children from weaning and up to 3 years of age may be particularly vulnerable to vitamin D depletion because of the rate at which calcium is being laid down in bone at this time and the limited availability of UV radiation for many children. Therefore vitamin drops containing vitamin D are recommended for all children up to 5 years of age. However, children who are regularly exposed to sunlight throughout the year (two to three times per week for about 20-30 minutes on hands and face) appear to have no dietary requirement for vitamin D (23). Those children who have limited exposure to sunlight or who are dark-skinned and have no dietary source of vitamin D require supplements. Only a few foods naturally contain vitamin D (D3, cholecalciferol) and all of these are animal products. Vitamin D3 is normally obtained from lanolin, which is derived from sheep's wool and therefore not acceptable to vegans. Foods fortified with a vegetarian source of vitamin D (vitamin D2, ergocalciferol) include margarine, some vegan milks and fortified breakfast cereals.

Interestingly enough, a study conducted in the south west of England on over 1.000 omnivorous 18 month old children found that the children were "unlikely to be deficient in any nutrients with the possible exceptions of iron, zinc and vitamin D" (26). I will be going on to iron and zinc containing foods, which are abundant in vegan diets.


IRON
Iron deficiency anemia is the most common childhood nutritional problem. It is no more likely to occur in vegan than non-vegan children (8). Vegan infants have been shown to have intakes above recommended levels but nonhaem iron has lower absorbability. Vitamin C and other organic acids commonly found in vegetables strongly enhance the absorption of non-haem iron. Vitamin c intakes of vegan children are frequently high and this, in conjunction with generous levels of dietary iron, may compensate for the lower bioavailability of non-haem iron. Good iron sources for vegan children include whole or enriched grains and grain products, iron-fortified cereals, legumes, green leafy vegetables, and dried fruits.

ZINC
Diets of vegan and non-vegan children often contain similar amounts of zinc. However, zinc from plant foods is not as well absorbed because plant foods contain phytate, which interferes with zinc absorption. Emphasizing foods that are good sources of zinc and protein such as pulses and nuts can increase the amount of zinc in the diet and promote absorption. Use of yeast-leavened bread and fermented soya products like tempeh and miso can improve zinc absorption (8). Zinc is present in all tissues and is involved in the major metabolic pathways contributing to the metabolism of proteins, carbohydrates, energy and lipids. Zinc supplements may be needed for young vegan children whose diet is based on high-phytate cereals and legumes (18). FSC and Seven Seas produce vegan vitamin and mineral supplements suitable for children.
VITAMIN B12
Vitamin B12 occurs in substantial amounts only in foods derived from animals. Vegan children should use foods fortified with vitamin B12 or vitamin B12 supplements. I cannot stress enough the importance of B12 in a child's diet. There are some very popular vegan advocates out there right now who say we don't have to worry about B12. The consequences of B12 deficiences which can cause irreversible damage are not worth the risk. From birth, vegan children need to be provided with sources of B12. A variety of foods fortified with vitamin B12 are available including some brands of vegan milk, meat substitutes, yeast extract, and some breakfast cereals. Quest and Vega Nutritionals are among a number of companies that produce vegan vitamin B12 supplements. Companies do make ingredient changes so please check out products before purchase

The Transition to a Vegan Diet

Although today more and more children are vegan from birth, many older children also become vegan. There are many ways to make a transition from a non-vegan to a vegan diet. Some families gradually eliminate dairy products and eggs, while others make a more abrupt transition. Regardless of which approach you choose, be sure to explain to your child what is going on and why, at your child's level of understanding. Offer foods that look familiar, at first. Peanut butter sandwiches seem to be universally popular and many children like pasta or baked beans. Gradually introduce new foods. Watch your child's weight closely. Weight loss may occur at first but if it continues or the child doesn't seem to be growing as rapidly, add more concentrated calories and reduce the fibre in your child's diet. Parents can help their children feel comfortable in their daily interactions with non-vegans by educating themselves on the variety of products and options now available on the market, such as meat substitutes. Some people might ask as a vegan why we would want to eat fake meats. Well in reality most vegans don't dislike the taste of meat, they just don't like eating animals. So when they eat these vegan products, especially the children, it makes them feel like they are part of the group.

Adolescents

As with any teenager, there is rapid growth between the years of 13 and 19 and nutritional needs are high at this time. Teenagers often do not make the most healthy food choices. Many teenagers skip breakfast and grab something on the way to school. Parents need to menu plan and hav e lots of ideas for foods to stock. Vegan convenience foods can be very useful such as bean mixes, veggie burgers and veggie sausages. Cereal bars and cartons of fruit juice are popular for those skipping breakfast on the way to school, dried fruits, trail mix, bagels, small cartons of fortified soya milks, yoghurts, hummus and pitta breads are popular snack foods.


No studies could be found that looked at vegan adolescents. Only one study addressed vegetarian adolescents (Hebbelinck et al 1999) which showed growth and maturation to be normal. It is hypothesised that there is delayed menarche in vegan girls.

Age at menarche is considered one of the strong individual indicators of timing of sexual maturation and is related to the health and nutritional status of the individual. Weight and the proportion of body fat is a good prediction of the rate of maturation. Adipose tissue plays an important role in the peripheral aromatisation of androgens to form oestrogens therefore, as vegan girls may be slimmer than their omnivorous peers, it would be predicted that sexual maturation would be delayed in vegan girls. This may be advantageous in that the early age of menarche is well-known to be associated with an increased risk of breast cancer in later life. Further studies are desperately needed.

As with any growing child, the teenager should be encouraged to eat a variety of foods and if energy (kcal) intake is adequate it is likely that nutrient needs are met. During puberty emotions are heightened and many teenagers become sensitive to environmental issues and wish to adopt a vegan diet. For those parents unfamiliar with vegan foods, it may be a difficult time. For some teenagers it may be a passing phase but for many it is the beginning of a lifestyle change and if addressed sensitively and sensibly a vegan lifestyle will be able to me et all the nutrients needed for good health. If adolescents, when changing to a vegan diet, experience weight loss, reduce the bulk of the diet by cutting down on fibre intake and adding in more energy dense foods such as nuts, dried fruit and vegetable oils.

It has been suggested that vegetarianism leads to anorexia but I can find no evidence to support this. Having worked with young adults with eating disorders I found a number chose to eat vegetarian foods in a bid to reduce their fat intake which is all part of the control aspect of the disease. Anorexia is not simply caused by an urge to be slim, it is a very complex illness with the lack of a clear sense of self, being central to the condition.

What Foods are Popular with Vegan Children?

Here are some ideas for foods that many vegan children like:

· Bagels with nut butter or hummus
· Bean burritos or tacos
· Fresh or dried fruit
· Mashed potatoes
· Oven-cooked chips
· Pancakes and waffles
· Pasta with tomato sauce
· Peanut butter and yeast extract sandwiches
· Pizza without cheese, topped with vegetables and pulses, tofu, or fake meat
· Raw vegetables with dips
· Shakes made with vegan milk and fruit
· Spaghetti with tomato sauce
· Tofu/vegetarian dogs
· Veggie burgers

Vegan diets planned in accord with current dietary recommendations can meet the nutritional needs of infants and children, can give children a better start in life and aid in the establishment of life-long healthy eating patterns.

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Published Online: 10 Ago 2002