there does not appear to be any benefit beyond six months. if a nursing mother decides to start feeding with an infant formula prior to four months, the recommendation is to use a formula containing cow's milk proteins. a different consideration occurs when a family history exists, either in parents or older siblings, of milk allergy. to avoid formula with intact cow's milk proteins, the product may be substituted with one containing extensively hydrolyzed milk proteins, with a non-dairy formula or with free amino acids. the hydrolyzation process breaks intact proteins into fragments, in theory reducing allergenic potential. in 2016, the u.s. food and drug administration approved a label claim for hydrolyzed whey protein as hypoallergenic. however, a meta-analysis published that same year disputed this claim, concluding that, based on dozens of clinical trials, there was insufficient evidence to support a claim that a partially hydrolyzed formula could reduce the risk of eczema. soy formula is a common substitution, but infants with milk allergy may also have an allergic response to soy formula. hydrolyzed rice formula is an option, as are the more expensive amino acid-based formulas. treatment the need for a dairy-free diet should be reevaluated every six months by testing milk-containing products low on the "milk ladder," such as fully cooked foods containing milk in which the milk proteins have been denatured, and ending with fresh cheese and milk. desensitization via oral immunotherapy is considered experimental. epinephrine autoinjectors are portable single-dose epinephrine-dispensing devices used to treat anaphylaxis. treatment for accidental ingestion of milk products by allergic individuals varies depending on the sensitivity of the person. an antihistamine such as diphenhydramine (benadryl) may be prescribed. sometimes prednisone will be prescribed to prevent a possible late-phase type i hypersensitivity reaction. severe allergic reactions (anaphylaxis) may require treatment with an epinephrine pen, an injection device designed for use by a non-healthcare professional when emergency treatment is warranted. a second dose is required in 16–35% of episodes. avoiding dairy further information: milk allergy § regulation of labeling most patients with milk allergy find it necessary to strictly avoid any item containing dairy ingredients because the threshold dose capable of provoking an allergic reaction can be quite small, especially in infants. an estimated 5% react to less than 30 milligrams of dairy proteins, and 1% react to less than one milligram. a more recent review calculated that the eliciting threshold dose for an allergic reaction in 1% of people (ed01) with confirmed cow's milk allergy is 0.1 mg of cow's milk protein. beyond the obvious ingredients (anything with milk, cheese, cream, curd, butter, ghee or yogurt in the name), in countries where allergen labeling is mandatory, the ingredient list is expected to list all ingredients. patients are advised to always carefully read food package labels, as sometimes even a familiar brand undergoes an ingredient change. in the u.s., for all foods except meat, poultry, egg-processed products and most alcoholic beverages, if an ingredient is derived from one of the required-label allergens, the product's packaging must display the food name in parentheses or include a statement separate from, but adjacent to, the ingredients list that specifically names each allergen. dairy-sourced protein ingredients include casein, caseinates, whey and lactalbumin, among others. the u.s. fda has a recall process for foods that contain undeclared allergenic ingredients. the university of wisconsin maintains a list of foods that may contain dairy proteins but are not always obvious from the name or type of food. this list contains the following examples: bread, baked goods and desserts caramel and nougat candies cereals, crackers, food bars chewing gum chocolate (both milk chocolate and dark chocolate) "cream of..." soups creamy pasta sauces creamy salad dressings eggnog flavored potato chips hot dogs and lunch meat instant mashed potatoes margarine medical food beverages non-dairy creamer sherbet pudding and custard there is a distinction between "contains ___" and "may contain ___." the first is a deliberate addition to the ingredients of a food and is required. the second addresses unintentional possible introduction of ingredients occurring during transportation, storage or at the manufacturing site, and is voluntary; this is known as precautionary allergen labeling. milk from other mammalian species such as goats and sheep should not be used as a substitute for cow's milk, as milk proteins from other mammals are often cross-reactive. however, some people with cow's milk allergy can tolerate goat's or sheep's milk. milk from camels, pigs, reindeer, horses and donkeys may also be tolerated in some cases. probiotic products have been tested, and some have been found to contain milk proteins that were not always indicated on the labels. cross-reactivity with soy infants, either still 100% breastfeeding or on infant formula, and young children may be prone to a combined cow's milk and soy protein allergy, referred to as "milk soy protein intolerance" (mspi). some recommend that nursing mothers discontinue consumption of foods containing dairy or soy ingredients. in opposition to this recommendation, a published scientific review stated that there was not yet sufficient evidence in the human trial literature to conclude that maternal dietary food avoidance during lactation would prevent or treat allergic symptoms in breastfed infants. a review presented information on milk allergy, soy allergy and cross-reactivity between the two. milk allergy was described as occurring in 2.2% to 2.8% of infants and declining with age. soy allergy was described as occurring in zero to 0.7% of young children. according to several studies cited in the review, between 10% and 14% of infants and young children with confirmed cow's milk allergy were determined to also be sensitized to soy and in some instances have a clinical reaction after consuming a soy-containing food. the research did not address whether the cause was two separate allergies or a cross-reaction resulting from a similarity in protein structure, as occurs for cow's milk and goat's milk. recommendations are that infants diagnosed as allergic to cow's milk infant formula should be switched to an extensively hydrolyzed protein formula rather than a soy whole-protein formula. prognosis milk allergy typically presents in the first year of life. the majority of children outgrow milk allergy by the age of ten. one large clinical trial reported resolutions of 19% by age 4 years, 42% by age 8 years, 64% by age 12 years, and 79% by 16 years. children are often better able to tolerate milk as an ingredient in baked goods relative to liquid milk. childhood predictors for adult persistence are anaphylaxis, high milk-specific serum ige, robust response to the skin prick test and absence of tolerance to milk-containing baked foods. resolution is more likely if baseline serum ige is lower or if ige-mediated allergy is absent, leaving only cell-mediated, non-ige allergy. people with confirmed cow's milk allergy may also demonstrate an allergic response to beef, especially when cooked rare, because of the presence of bovine serum albumin. in u.s. government diet and health surveys conducted from 2007 to 2010, 6,189 children ages 2–17 were assessed. for those classified as allergic to cow's milk, mean weight, height and body-mass index were significantly lower than for their non-allergic peers. this was not true for children with other food allergies. diet assessment showed a significant 23% reduction of calcium intake and near-significant trends for lower vitamin d and total calorie intake. epidemiology incidence and prevalence are terms commonly used in describing disease epidemiology. incidence is newly diagnosed cases, which can be expressed as new cases per year per million people. prevalence is the number of cases alive, which may be expressed in terms of existing cases per million over a period of time. the percentage of babies in developed countries with milk allergy is between 2% and 3%. this estimate is for antibody-based allergy; figures for allergy based on cellular immunity are unknown. the percentage declines as children age. national survey data in the u.s. collected from 2005 to 2006 showed that from age six and older, the percentage with ige-confirmed milk allergy was less than 0.4%. for all age groups, a review conducted in europe estimated that 0.6% had milk allergy. regulation dairy allergy was one of the earliest food allergies to be recorded. an ancient greek medical text attributed to the doctor hippocrates (c. 460 – c. 370 bc) notes that some foods are harmful to certain individuals but not others, and "...cheese does not harm all men alike; some can eat their fill of it without the slightest hurt, nay, those it agrees with are wonderfully strengthened thereby. others come off badly." the text attempts to explain the reaction to the cheese in terms of hippocratic humorism, stating that some constitutions are naturally "hostile to cheese, and roused and stirred to action under its influence." with the passage of mandatory labeling laws, food-allergy awareness has increased, with impacts on the quality of life for children, their parents and their immediate caregivers. in the u.s., the food allergen labeling and consumer protection act of 2004 (falcpa) mandates disclosure of allergen information on food packaging, and many restaurants have added allergen warnings to their menus. school systems maintain protocols regarding foods that cannot be brought into the school. despite all of these precautions, people with serious allergies must maintain awareness that accidental exposure can occur in other peoples' homes, at school or in restaurants. regulation of labeling further information: milk allergy § regulation of labelingan example of "may contain traces of..." as a means of listing trace amounts of allergens in a food product due to cross-contamination during manufacture. in response to the risk that certain foods pose to those with food allergies, some countries have responded by instituting labeling laws that require food products to clearly inform consumers if they contain major allergens or allergen byproducts among the ingredients intentionally added to foods. however, labeling laws do not mandate the declaration of the presence of trace amounts in the final product as a consequence of cross-contamination, except in brazil. ingredients intentionally added in the us, falcpa requires companies to disclose on the label whether a packaged food product contains a major food allergen added intentionally: cow's milk, peanuts, eggs, shellfish, fish, tree nuts, soy and wheat. this list originated in 1999 from the world health organisation codex alimentarius commission. to meet falcpa labeling requirements, if an ingredient is derived from one of the required-label allergens, then it must either have its "food sourced name" in parentheses, for example "casein (milk)," or as an alternative, there must be a statement separate but adjacent to the ingredients list: "contains milk" (and any other of the allergens with mandatory labeling). dairy food listing is also mandatory in the european union and more than a dozen other countries. falcpa applies to packaged foods regulated by the fda, which does not include poultry, most meats, certain egg products, and most alcoholic beverages. however, some meat, poultry, and egg processed products may contain allergenic ingredients, such as added milk proteins. these products are regulated by the food safety and inspection service (fsis), which requires that any ingredient be declared in the labeling only by its common or usual name. neither the identification of the source of a specific ingredient in a parenthetical statement nor the use of statements to alert for the presence of specific ingredients, like "contains: milk", are mandatory according to fsis. falcpa also does not apply to food prepared in restaurants. trace amounts as a result of cross-contamination the value of allergen labeling other than for intentional ingredients is controversial. this concerns labeling for ingredients present unintentionally as a consequence of cross-contact or cross-contamination at any point along the food chain (during raw material transportation, storage or handling, due to shared equipment for processing and packaging, etc.). experts in this field propose that if allergen labeling is to be useful to consumers, and healthcare professionals who advise and treat those consumers, ideally there should be agreement on which foods require labeling, threshold quantities below which labeling may be of no purpose, and validation of allergen detection methods to test and potentially recall foods that were deliberately or inadvertently contaminated. labeling regulations have been modified to provide for mandatory labeling of ingredients plus voluntary labeling, termed precautionary allergen labeling (pal), also known as "may contain" statements, for possible, inadvertent, trace amount, cross-contamination during production. pal labeling can be confusing to