Food fortification

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Food fortification is the addition of micronutrients (essential trace elements and vitamins) to food products. Food enrichment specifically means adding back nutrients lost during food processing, while fortification includes adding nutrients not naturally present. [1] Food manufacturers and governments have used these practices since the 1920s to help prevent nutrient deficiencies in populations. Common nutrient deficiencies in a region often result from local soil conditions or limitations of staple foods. The addition of micronutrients to staples and condiments can prevent large-scale deficiency diseases in these cases. [2]

Contents

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. [1] 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. [3] Undernutrition and nutrient deficiency is estimated globally to cause the deaths of between 3 and 5 million people per year. [2]

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. [4]

Food fortification can also be categorized according to the stage of addition:

  1. Commercial and industrial fortification (wheat flour, corn meal, cooking oils)
  2. Biofortification (breeding crops to increase their nutritional value, which can include both conventional selective breeding, and genetic engineering)
  3. Home fortification (example: vitamin D drops) [5]

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. [1] 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. [6] 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. [6]

In Canada, the Food and Drug Regulations have outlined specific criteria which justify food fortification:

  1. To replace nutrients which were lost during manufacturing of the product (e.g. the manufacturing of flour [7] )
  2. To act as a public health intervention
  3. 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.)
  4. 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. [5]

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 [8] and country profiles. [9] The website is maintained by the Food Fortification Initiative, GAIN, Iodine Global Network, and the Micronutrient Forum. [10]

Argentina

In Argentina, wheat flour must by law (Ley 25.630 of 2002) [11] be fortified with iron, thiamine (vitamin B1), riboflavin (B2), niacin (B3), and folic acid (B9). [12]

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). [13]

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. [14] [15]

Philippines

The Philippine law on food fortification has two components: mandatory (covering select staples) [16] 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. [17]

United Kingdom

UK law (The Bread and Flour Regulations 1998) [18] [19] 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. [20]

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. [21] 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. [4] 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

Manufacturers once proposed selling fortified junk food and beer, but US FDA policies of the time forbade it. Ad for "Vitamin Donut" (FDA 168) (8212305596).jpg
Manufacturers once proposed selling fortified junk food and beer, but US FDA 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. [22]

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. [23]

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.[ citation needed ]

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. [24] 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.[ citation needed ]

In many cases, the micronutrients added to foods in fortification are synthetic.[ citation needed ]

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.[ medical citation needed ]

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. [25]

The Food Fortification Initiative lists all countries in the world that conduct fortification programs, [26] 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. [27] The most commonly fortified vitamin – as used in 62 countries – is folate; the most commonly fortified food is wheat flour (enriched flour). [27] Examples of foods and beverages that have been fortified:

Iodized 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 [28]

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. [29] 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.[ medical citation needed ]

Diseases that are associated with an iodine deficiency include: intellectual disabilities, hypothyroidism, and goiter. There is also a risk of various other growth and developmental abnormalities.[ medical citation needed ]

Folate

Folate (as a fortification ingredient, folic acid) functions in reducing blood homocysteine levels, forming red blood cells, proper growth and division of cells and preventing neural tube defects (NTDs). [30] In many industrialized countries, the addition of folic acid to flour has prevented a significant number of NTDs in infants. Two common types of NTDs, spina bifida and anencephaly, affect approximately 2500-3000 infants born in the US annually. Research trials have shown the ability to reduce the incidence of NTDs by supplementing pregnant mothers with folic acid by 72%. [31]

Niacin

Niacin (a form of vitamin B3) has been added to bread in the US since 1938 (when voluntary addition started), a program which substantially reduced the incidence of pellagra. [32] Pellagra was seen amongst poor families who used corn as their main dietary staple. Although corn itself does contain niacin, it is not a bioavailable form unless it undergoes nixtamalization (treatment with alkali, traditional in Native American cultures) and therefore was not contributing to the overall intake of niacin.[ medical citation needed ]

Diseases associated with niacin deficiency include pellagra which consisted of signs and symptoms called the three D's-"dermatitis, dementia, and diarrhea." Others may include vascular or gastrointestinal diseases. [33] Common diseases which present a high frequency of niacin deficiency include alcoholism, anorexia nervosa, HIV infection, gastrectomy, malabsorptive disorders, certain cancers and their associated treatments. [33]

Vitamin D

Since Vitamin D is a fat-soluble vitamin, it cannot be added to a wide variety of foods. Foods that it is commonly added to are margarine, vegetable oils and dairy products. [34] During the late 1800s, after the discovery of curing conditions of scurvy and beriberi had occurred, researchers were aiming to see if the disease, later known as rickets, could also be cured by food. Their results showed that sunlight exposure and cod liver oil were the cure. It was not until the 1930s that vitamin D was actually linked to curing rickets. [35] This discovery led to the fortification of common foods such as milk, margarine, and breakfast cereals in the USA and in some European countries (some of which later forbade the practice due to finding neonates suffering from vitamin D intoxication). [36]

Diseases associated with a vitamin D deficiency include rickets, osteoporosis, and certain types of cancer (breast, prostate, colon and ovaries). It has also been associated with increased risks for fractures, heart disease, type 2 diabetes, autoimmune and infectious diseases, asthma and other wheezing disorders, myocardial infarction, hypertension, congestive heart failure, and peripheral vascular disease. [36]

Fluoride

Although fluoride is not considered an essential mineral, it is useful in prevention of tooth decay and maintaining adequate dental health. [37] [38] In the mid-1900s it was discovered that towns with a high level of fluoride in their water supply was causing the residents' teeth to have both brown spotting and a strange resistance to dental caries. This led to the fortification of water supplies with fluoride in safe amounts (or reduction of naturally occurring levels) to retain the properties of resistance to dental caries but avoid the staining caused by fluorosis (a condition caused by excessive fluoride intake). [39] The tolerable upper intake level (UL) set for fluoride ranges from 0.7 mg/day for infants aged 0–6 months and 10 mg/day for adults over the age of 19.[ citation needed ]

See also

Related Research Articles

<span class="mw-page-title-main">Riboflavin</span> Vitamin, dietary supplement, and yellow food dye

Riboflavin, also known as vitamin B2, is a vitamin found in food and sold as a dietary supplement. It is essential to the formation of two major coenzymes, flavin mononucleotide and flavin adenine dinucleotide. These coenzymes are involved in energy metabolism, cellular respiration, and antibody production, as well as normal growth and development. The coenzymes are also required for the metabolism of niacin, vitamin B6, and folate. Riboflavin is prescribed to treat corneal thinning, and taken orally, may reduce the incidence of migraine headaches in adults.

<span class="mw-page-title-main">Vitamin</span> Nutrients required by organisms in small amounts

Vitamins are organic molecules that are essential to an organism in small quantities for proper metabolic function. Essential nutrients cannot be synthesized in the organism in sufficient quantities for survival, and therefore must be obtained through the diet. For example, vitamin C can be synthesized by some species but not by others; it is not considered a vitamin in the first instance but is in the second. Most vitamins are not single molecules, but groups of related molecules called vitamers. For example, there are eight vitamers of vitamin E: four tocopherols and four tocotrienols.

<span class="mw-page-title-main">Niacin</span> Organic compound and a form of vitamin B3

Niacin, also known as nicotinic acid, is an organic compound and a vitamer of vitamin B3, an essential human nutrient. It is produced by plants and animals from the amino acid tryptophan. Niacin is obtained in the diet from a variety of whole and processed foods, with highest contents in fortified packaged foods, meat, poultry, red fish such as tuna and salmon, lesser amounts in nuts, legumes and seeds. Niacin as a dietary supplement is used to treat pellagra, a disease caused by niacin deficiency. Signs and symptoms of pellagra include skin and mouth lesions, anemia, headaches, and tiredness. Many countries mandate its addition to wheat flour or other food grains, thereby reducing the risk of pellagra.

<span class="mw-page-title-main">Folate</span> Vitamin B9; nutrient essential for DNA synthesis

Folate, also known as vitamin B9 and folacin, is one of the B vitamins. Manufactured folic acid, which is converted into folate by the body, is used as a dietary supplement and in food fortification as it is more stable during processing and storage. Folate is required for the body to make DNA and RNA and metabolise amino acids necessary for cell division and maturation of blood cells. As the human body cannot make folate, it is required in the diet, making it an essential nutrient. It occurs naturally in many foods. The recommended adult daily intake of folate in the U.S. is 400 micrograms from foods or dietary supplements.

A nutrient is a substance used by an organism to survive, grow and reproduce. The requirement for dietary nutrient intake applies to animals, plants, fungi and protists. Nutrients can be incorporated into cells for metabolic purposes or excreted by cells to create non-cellular structures such as hair, scales, feathers, or exoskeletons. Some nutrients can be metabolically converted into smaller molecules in the process of releasing energy such as for carbohydrates, lipids, proteins and fermentation products leading to end-products of water and carbon dioxide. All organisms require water. Essential nutrients for animals are the energy sources, some of the amino acids that are combined to create proteins, a subset of fatty acids, vitamins and certain minerals. Plants require more diverse minerals absorbed through roots, plus carbon dioxide and oxygen absorbed through leaves. Fungi live on dead or living organic matter and meet nutrient needs from their host.

Vitamin deficiency is the condition of a long-term lack of a vitamin. When caused by not enough vitamin intake it is classified as a primary deficiency, whereas when due to an underlying disorder such as malabsorption it is called a secondary deficiency. An underlying disorder can have 2 main causes:

B vitamins are a class of water-soluble vitamins that play important roles in cell metabolism and synthesis of red blood cells. They are a chemically diverse class of compounds.

<span class="mw-page-title-main">White bread</span> Type of bread made from white wheat flour

White bread typically refers to breads made from wheat flour from which the bran and the germ layers have been removed from the whole wheatberry as part of the flour grinding or milling process, producing a light-colored flour.

<span class="mw-page-title-main">Vegetarian nutrition</span> Nutritional and human health aspects of vegetarian diets

Vegetarian nutrition is the set of health-related challenges and advantages of vegetarian diets.

Micronutrients are essential dietary elements required by organisms in varying quantities to regulate physiological functions of cells and organs. Micronutrients support the health of organisms throughout life.

Enriched flour is flour with specific nutrients added to it. These nutrients include iron and B vitamins. Calcium may also be supplemented. The purpose of enriching flour is to replenish the nutrients in the flour to match the nutritional status of the unrefined product. This differentiates enrichment from fortification, which is the process of introducing new nutrients to a food.

<span class="mw-page-title-main">Folate deficiency</span> Abnormally low level of folate (vitamin B9) in the body

Folate deficiency, also known as vitamin B9 deficiency, is a low level of folate and derivatives in the body. This may result in megaloblastic anemia in which red blood cells become abnormally large, and folate deficiency anemia is the term given for this medical condition. Signs of folate deficiency are often subtle. Symptoms may include fatigue, heart palpitations, shortness of breath, feeling faint, open sores on the tongue, loss of appetite, changes in the color of the skin or hair, irritability, and behavioral changes. Temporary reversible infertility may occur. Folate deficiency anemia during pregnancy may give rise to the birth of low weight birth premature infants and infants with neural tube defects.

<span class="mw-page-title-main">Vitamin A deficiency</span> Disease resulting from low Vitamin A concentrations in the body

Vitamin A deficiency (VAD) or hypovitaminosis A is a lack of vitamin A in blood and tissues. It is common in poorer countries, especially among children and women of reproductive age, but is rarely seen in more developed countries. Nyctalopia is one of the first signs of VAD, as the vitamin has a major role in phototransduction; but it is also the first symptom that is reversed when vitamin A is consumed again. Xerophthalmia, keratomalacia, and complete blindness can follow if the deficiency is more severe.

<span class="mw-page-title-main">Refined grains</span> Cereal containing endosperm, but not bran nor germ

Refined grains have been significantly modified from their natural composition, in contrast to whole grains. The modification process generally involves the mechanical removal of bran and germ, either through grinding or selective sifting.

Vitamins occur in a variety of related forms known as vitamers. A vitamer of a particular vitamin is one of several related compounds that performs the functions of said vitamin and prevents the symptoms of deficiency of said vitamin.

<span class="mw-page-title-main">Nutrition International (organization)</span> Nonprofit organization

Nutrition International, formerly the Micronutrient Initiative (MI), is an international not for profit agency based in Canada that works to eliminate vitamin and mineral deficiencies in developing countries. Although often only required by the body in very small amounts, vitamin and minerals – also known as micronutrients – support an array of critical biological functions including growth, immune function and eye function, as well as foetal development of the brain, the nervous system, and the skeletal system. Micronutrient deficiency is a form of malnutrition and is a recognized health problem in many developing countries. Globally, more than two billion people live with vitamin and mineral deficiencies.

<span class="mw-page-title-main">Nutritional neuroscience</span> Scientific discipline

Nutritional neuroscience is the scientific discipline that studies the effects various components of the diet such as minerals, vitamins, protein, carbohydrates, fats, dietary supplements, synthetic hormones, and food additives have on neurochemistry, neurobiology, behavior, and cognition.

Relatively speaking, the brain consumes an immense amount of energy in comparison to the rest of the body. The mechanisms involved in the transfer of energy from foods to neurons are likely to be fundamental to the control of brain function. Human bodily processes, including the brain, all require both macronutrients, as well as micronutrients.

Vitamin B<sub>3</sub> Class of chemically related vitamers

Vitamin B3, colloquially referred to as niacin, is a vitamin family that includes three forms, or vitamers: niacin (nicotinic acid), nicotinamide (niacinamide), and nicotinamide riboside. All three forms of vitamin B3 are converted within the body to nicotinamide adenine dinucleotide (NAD). NAD is required for human life and people are unable to make it within their bodies without either vitamin B3 or tryptophan. Nicotinamide riboside was identified as a form of vitamin B3 in 2004.

The Food Fortification Initiative (FFI) is an organization that promotes the fortification of industrially milled flours and cereals. FFI assists country leaders in promoting, planning, implementing, and monitoring the fortification of industrially milled wheat flour, maize flour, and rice. FFI is the only global organization focused exclusively on these three widely consumed grains. FFI operates in approximately thirty countries worldwide and tracks food fortification progress for 196 countries.

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