food fortification food fortification food fortification or enrichment is the process of adding micronutrients (essential trace elements and vitamins) to food. it can be carried out by food manufacturers, or by governments as a public health policy which aims to reduce the number of people with dietary deficiencies within a population. the predominant diet within a region can lack particular nutrients due to the local soil or from inherent deficiencies within the staple foods; the addition of micronutrients to staples and condiments can prevent large-scale deficiency diseases in these cases. as defined by the world health organization (who) and the food and agricultural organization of the united nations (fao), fortification refers to "the practice of deliberately increasing the content of an essential micronutrient, i.e. vitamins and minerals (including trace elements) in a food, to improve the nutritional quality of the food supply and to provide a public health benefit with minimal risk to health", whereas enrichment is defined as "synonymous with fortification and refers to the addition of micronutrients to a food which are lost during processing". food fortification has been identified as the second strategy of four by the who and fao to begin decreasing the incidence of nutrient deficiencies at the global level. as outlined by the fao, the most commonly fortified foods are cereals and cereal-based products; milk and dairy products; fats and oils; accessory food items; tea and other beverages; and infant formulas. undernutrition and nutrient deficiency is estimated globally to cause the deaths of between 3 and 5 million people per year. types fortification is present in common food items in two different ways: adding back and addition. flour loses nutritional value due to the way grains are processed; enriched flour has iron, folic acid, niacin, riboflavin, and thiamine added back to it. conversely, other fortified foods have micronutrients added to them that don't naturally occur in those substances. an example of this is orange juice, which often is sold with added calcium. food fortification can also be categorized according to the stage of addition: commercial and industrial fortification (wheat flour, corn meal, cooking oils) biofortification (breeding crops to increase their nutritional value, which can include both conventional selective breeding, and genetic engineering) home fortification (example: vitamin d drops) rationale micronutrients serve an important role in bodily development and growth. deficiencies of these micronutrients may cause improper development or even disease. the who and fao, among many other nationally recognized organizations, have recognized that there are over 2 billion people worldwide who have a variety of micronutrient deficiencies. in 1992, 159 countries pledged at the fao/who international conference on nutrition to make efforts to help combat these issues of micronutrient deficiencies, highlighting the importance of decreasing the number of those with iodine, vitamin a, and iron deficiencies. a significant statistic that led to these efforts was the discovery that approximately 1 in 3 people worldwide were at risk for either an iodine, vitamin a, or iron deficiency. although it is recognized that food fortification alone will not combat this deficiency, it is a step towards reducing the prevalence of these deficiencies and their associated health conditions. in canada, the food and drug regulations have outlined specific criteria which justify food fortification: to replace nutrients which were lost during manufacturing of the product (e.g. the manufacturing of flour) to act as a public health intervention to ensure the nutritional equivalence of substitute foods (e.g. to make butter and margarine similar in content, soy milk and cow's milk, etc.) to ensure the appropriate vitamin and mineral nutrient composition of foods for special dietary purposes (e.g., gluten-free products, low sodium, or any other products specifically designed for special dietary requirements from an individual). there are also several advantages to approaching nutrient deficiencies among populations via food fortification as opposed to other methods. these may include, but are not limited to: treating a population without specific dietary interventions therefore not requiring a change in dietary patterns, continuous delivery of the nutrient, does not require individual compliance, and potential to maintain nutrient stores more efficiently if consumed regularly. around the world the subsections below describe fortifications in some jurisdictions around the world. a more comprehensive view is given by the online global fortification data exchange. it indicates which of 197 countries worldwide have mandatory and voluntary food fortification in their datasets and country profiles. the website is maintained by the food fortification initiative, gain, iodine global network, and the micronutrient forum. argentina in argentina, wheat flour must by law (ley 25.630 of 2002) be fortified with iron, thiamine (vitamin b1), riboflavin (b2), niacin (b3), and folic acid (b9). colombia wheat flour sold in colombia must by law be fortified with vitamin b1, vitamin b2, niacin (b3), folic acid (b9) and iron (decreto 1944 of 1996). el salvador, guatemala, honduras and nicaragua the four countries, also called the c-4, all legally require wheat flour to be fortified with vitamins b1, b2, b3, b9, and iron. philippines the philippine law on food fortification has two components: mandatory (covering select staples) and voluntary (under the sangkap pinoy program). the latter has been criticized for covering only low nutritional-value food, namely, junk food, to enable them to be sold in schools. united kingdom uk law (the bread and flour regulations 1998) requires that all flour (except wholemeal and some self-raising flours) be fortified with calcium. wheat flour must also be fortified with iron, thiamine (vitamin b1) and vitamin b3. united states in the 1920s, food fortification emerged as a strategy in the united states to address and prevent the lack of micronutrients in the population's diet. specifically, it was discovered in the 1930s and 1940s, that micronutrient deficiency is often linked to specific diseases and syndromes. consequently, the committee on food and nutrition suggested that micronutrients be added to flour. in 1980, the food and drug administration put into action its food fortification policy which included six fundamental rules. in addition to establishing safety guidelines of food fortification, this policy aimed to ensure that food fortification was solely for when the supplemental micronutrient had a national deficiency and that the food chosen to provide that nutrient was consumed by enough of the population to make a change. this policy also emphasized the importance of clinical data, a shift from earlier policies which relied on dietary data alone. the 2002 farm bill (p.l. 107–171, sec. 3013) requires the administrator of usaid, in consultation with the secretary of agriculture, to establish micronutrient fortification programs under p.l. 480 food aid. section 3013 replaces a pilot program similarly named and authorized in the 1996 farm bill (p.l. 104–127, sec. 415). under the programs, grains and other commodities made available to countries selected for participation will be fortified with micronutrients (e.g., iron, vitamin a, iodine, and folic acid). criticism the who states that limitations to food fortification may include human rights issues indicating that consumers have the right to choose if they want fortified products or not, the potential for insufficient demand of the fortified product, increased production costs leading to increased retail costs, the potential that the fortified products will still not be a solution to nutrient deficiencies among low-income populations who may not be able to afford the new product, and children who may not be able to consume adequate amounts thereof. manufacturers once proposed selling fortified junk food and beer, but usfda policies of the time forbade it in addition to criticism of government-mandated fortification, food companies have been criticized for indiscriminate enrichment of foods for marketing purposes. food safety worries led to legislation in denmark in 2004 restricting foods fortified with extra vitamins or minerals. products banned include: rice krispies, shreddies, horlicks, ovaltine and marmite. limited absorption one factor that limits the benefits of food fortification is that isolated nutrients added back into a processed food that has had many of its nutrients removed, does not always result in the added nutrients being as bioavailable as they would be in the original, whole food. an example is skim milk that has had the fat removed, and then had vitamin a and vitamin d added back. vitamins a and d are both fat-soluble and non-water-soluble, so a person consuming skim milk without fats may not be able to absorb as much of these vitamins as one would be able to absorb from drinking whole milk. on the other hand, the nutrient added as a fortificant may have a higher bioavailability than from foods, which is the case with folic acid used to increase folate intakes. phytochemicals such as phytic acid in cereal grains can also impact nutrient absorption, limiting the bioavailability of intrinsic and additional nutrients, and reducing the effectiveness of fortification programs. different forms of micronutrients there is a concern that micronutrients are legally defined in such a way that does not distinguish between different forms, and that fortified foods often have nutrients in a balance that would not occur naturally. for example, in the u.s., food is fortified with folic acid, which is one of the many naturally-occurring forms of folate, and which only contributes a minor amount to the folates occurring in natural foods. in many cases, such as with folate, it is an open question of whether or not there are any benefits or risks to consuming folic acid in this form. in many cases, the micronutrients added to foods in fortification are synthetic. certain forms of micronutrients can be actively toxic in a sufficiently high dose, even if other forms are safe at the same or much higher doses. there are examples of such toxicity in both synthetic and naturally occurring forms of vitamins. retinol, the active form of vitamin a, is toxic in a much lower dose than other forms, such as beta carotene. menadione, a phased-out synthetic form of vitamin k, is also known to be toxic. examples of fortification in foods many foods and beverages worldwide have been fortified, whether a voluntary action by the product developers or by law. although some may view these additions as strategic marketing schemes to sell their product, there is a lot of work that must go into a product before simply fortifying it. to fortify a product, it must first be proven that the addition of this vitamin or mineral is beneficial to health, safe, and an effective method of delivery. the addition must also abide by all food and labeling regulations and support nutritional rationale. from a food developer's point of view, they also need to consider the costs associated with this new product and whether there will be a market to support the change. the food fortification initiative lists all countries in the world that conduct fortification programs, and within each country, what nutrients are added to which foods, and whether those programs are voluntary or mandatory. vitamin fortification programs exist in one or more countries for folate, niacin, riboflavin, thiamine, vitamin a, vitamin b6, vitamin b12, vitamin d and vitamin e. mineral fortification programs include calcium, fluoride, iodine, iron, selenium and zinc. as of december 21, 2018, 81 countries required food fortification with one or more vitamins. the most commonly fortified vitamin – as used in 62 countries – is folate; the most commonly fortified food is wheat flour (enriched flour). examples of foods and beverages that have been fortified: iodized salt main article: iodised salt iodine deficiency disorder (idd) is the single greatest cause of preventable mental retardation. severe deficiencies cause cretinism, stillbirth and miscarriage. but even mild deficiency can significantly affect the learning ability of populations. today over 1 billion people in the world suffer from iodine deficiency, and 38 million babies born every year are not protected from brain damage due to idd."—kul gautam, deputy executive director, unicef, october 2007 iodised salt has been used in the united states since before world war ii. it was discovered in 1821 that goiters could be treated by the use of iodized salts. however, it was not until 1916 that the use of iodized salts could be tested in a research trial as a preventative measure against goiters. by 1924, it became readily available in the us. currently in canada and the us, the rda for iodine is as low as 90 µg/day for children (4–8 years) and as high as 290 µg/day for breast-feeding mothers.