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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. References 1. 2. Acosta, Phyllis B. Availability of essential amino acids and nitrogen in vegan diets Amer J Clin Nutr. 1988;48:868-874. Bresson J. Protein and energy requirements in healthy and ill paediatric patients. 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