Download protein needs for vegan children

Ryan Heinrick
NTR 441
April 01, 2006
Research Paper
PROTEIN RECOMMENDATIONS FOR VEGAN INFANTS AND CHILDREN
Dietary recommendations of macronutrients and micronutrients are reasonably
well understood for the majority of the healthy adult population. Stratification of the
various dietary recommendations widens when assessing the individual nutrient needs for
infants, children, and adolescents due to the rapid growth rates depending on their age
(8,12). The typical American diet consists of a balance of nutrients and energy from both
animal (non-vegetarian) and non-animal (vegetarian) sources. Most nutrient
recommendations to maintain health in infants, children, adolescents, and adults are met
when following a typical American diet. Due to the nature of these recommendations
(minimum levels of nutrients to maintain health), problems tend to be more apparent
when actual intake falls below the recommendations. One population of children and
infants in particular are at a greater risk to fall short on protein macronutrient needs (1-4).
This population follows a vegan diet that is devoid any animal products.
When a healthy adult chooses to restrict their diet, they take the risk of inducing
some kind of specific nutrient or total energy deficiency. This is true for children who
cannot make food choices but instead depend on their caregivers to make dietary choices
for them (12). Veganism is a diet regimen that restricts all forms of animal products from
the diet such as eggs, dairy products, gelatin, and sometimes even honey (4). Veganism
differs from vegetarian diets (ovo-/lacto-) because the most liberal vegetarian diet
eliminates animal meat and fish from the diet but may allow persons to consume other
animal products such as butter, cheese, milk, and eggs. Individuals who consider
themselves vegetarian fall into a wide range of dietary practices. Vegans, more so than
ovo/lacto-vegetarians, are at a higher risk to develop protein deficiencies than vegetarians
and non-vegetarians because a vegan diet completely eliminates high biological value
(HBV) protein from animal sources (1,4-6,12).
The terms “infants and children” are actually a range of ages when determining
nutrient needs and can change considerably based on what age bracket the infant or child
falls into. The first category is infants and the first sub category is zero to six months of
age. The protein adequate intake (AI) for this range is 9.1g/day. Next are infants ages
seven to 12 months with a protein recommended dietary allowance (RDA) of 13.5 g/day.
Once the infant reaches their first year, they are considered a child. Children ages one to
three have an RDA of 13g/day of protein. The last category of Children is ages four to
eight and the RDA value is 19g/day of protein. The aforementioned values of protein are
the DRI levels set by the federal government (1,9). Early infant (ages zero to six months)
protein requirements do not have an RDA value associated with them and instead use an
adequate intake (AI) value because not enough research has been done to determine a
solid recommended dietary allowance for protein. In addition to the DRI value, another
set of values specifically for macronutrients that is called the Acceptable Macronutrient
Distribution Range (AMDR) has been developed. This range indicates adequate values
of a particular macronutrient that protects against chronic diseases. Deviation either
above or below the AMDR may increase the risk of associated chronic diseases. The
protein AMDR for infants is not determinable due to lack of data of adverse effects in the
age group. However, for children ages one to three the AMDR for protein is five to
20g/day. For children in the four to eight year group range, the AMDR for protein is 1030g/day of protein. Protein requirements for infants are estimated from the intake of milk
by normally growing infants and protein content of milk. Amino acids should be
provided to infants and children in amounts that do not exceed the capacity of the liver
and kidney to function, yet allow for appropriate growth and development (2).
Vegan infants and children typically meet and exceed protein recommendations
often beyond the ceiling of the protein AMDR (4,6,9-12). Several researchers feel that
protein for vegan infants and children should be much greater than the levels indicated by
the DRIs (1,2,7). The vegan diet is relatively high in fiber compared to the typical
American diet and due to this characteristic of the vegan diet, vegans of all ages (except
infants and children who are exclusively breast-fed (8-10)) ingest a significantly larger
amount of both fermentable and non-fermentable fiber than their non-vegetarian
counterparts (1,5). While fiber can be advantageous to adults, it can lead to disastrous
effects in the very young because of the properties of fiber in the digestive tract. High
intake of dietary fiber can lead to increased intestinal nitrogen losses (due to physical
contact of fibrous material with gut mucosal cells), decreased nitrogen retention, and
decreased nitrogen absorption (5). Vegetable protein has a lower bioavailability than its
animal protein counterparts (1,4,9,13). Other ways dietary protein may not be properly
utilized is due to the intrinsic inhibition of proteolytic enzymes, food preparation
techniques, reactions with oxidizing fats, interactions with dietary sucrose and high
fructose corn syrup which may limit (or completely eliminate) specific essential amino
acids (1,5). It is important to note that individuals of all ages could develop specific
amino acid deficiencies despite the fact they have an adequate total protein intake (4).
Studies with vegetarian and vegans typically only look at dietary intake of protein
and do not account and nitrogen losses due to the increased intake of dietary fiber. Thus,
caregivers of vegan children need to go beyond the standard recommendations of protein
and increase intakes to counteract nitrogen lost in the process of digestion (1,2,9). In
order to provide more protein in the diet of an infant or child vegan, foods naturally
higher in protein should be used more often as well as the use of complimentary sources
of protein to maintain an ideal mixture of amino acids in the diet. It is not necessary to
practice strict protein combining, but rather eat a variety of foods throughout the day.
Adjusted values of dietary protein should be considered for infants and children because
of the nature of the vegan diet (1,4,6,9).
To allow for amino acid composition and digestibility of a vegan diet, it appears
that protein needs must be increased by 30% to 35% for children younger than age two
years, 20% to 30%-for ages two to six years, and 15% to 20% for children over age six
years. (9). This would put the protein range from 18 to 34 grams of protein/day for
vegan children of both sexes who are consuming solid vegan foods. Bresson (2) goes
farther and recommends 40g/day of protein between ages of one and two and 60g/day at
four years of age. Vegan children should be eating on average two to three sources of
meat substitutes per day. It is possible for vegan infants and children to be towards the
lower end of growth charts and still have adequate protein intake (7,11,12). The problem
is that vegan infants and children tend to consume less total calories than their nonvegetarian counterparts, which adversely affect their growth and development. Another
possible explanation that has been discussed previously is the limited bioavailability of
protein which may contribute to poor growth rates. It is important to increase the amount
of protein and energy to account for nitrogen and energy losses.
Infants and children have relatively higher energy and protein needs per kilogram
of body weight than do adults. According to the Dietary Reference Intakes, protein
should make up 10-35% of their caloric intake. Non-vegetarians tend to receive more of
their dietary energy from protein versus vegans. Due to the higher energy needs per
kilogram of body weight and the bioavailability of plant proteins, it is important for
vegan children to consume higher amounts of energy and protein in the diet than nonvegetarians. Most vegan infants and children consume adequate amounts of protein that
meet or exceed recommended levels. However, due to the nature of fiber and a high fiber
diet, some dietary nitrogen is lost the digestion process resulting in seemingly adequate
protein intake, but in reality the compromised digestibility and absorption can result in a
protein deficiency (and in many cases, a subsequent energy deficit). To maintain energy
requirements, caregivers of vegan infants and children should be mindful of the potential
pitfalls that may arise due to the nature of the vegan diet and make efforts to
accommodate these unique dietary challenges. There is no reason why vegan children
cannot grow up to be strong and healthy like their non-vegetarian counterparts if the
vegan diet is followed correctly.
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