Vitamin D fortification can play a substantial role in addressing public health concerns about Vitamin D status. Yet with many unknowns, the bakery industry is wise to proceed with caution until more science-based guidance is released.
By: Roberta L. Duyff, food and nutrition consultant
Duyff Associates, St. Louis, Mo.
Vitamin D Fortification: A United States' Perspective
Vitamin D -- it’s often called the “nutrient of the era.” Although well recognized for its role in growth and bone health, in recent decades this fat-soluble vitamin has received little attention. Fortification of milk in the 1930s in the United States essentially eliminated rickets, caused by a Vitamin D deficiency. Yet emerging scientific research indicates that Vitamin D may have more far-reaching health benefits – ironically, at a time when Vitamin D status and the re-emergence of rickets are concerns once again.
While the human body makes Vitamin D through exposure to sunlight, it's also needed in the diet. Among the many reasons: many people don’t get enough sunlight exposure to make what the body requires. Studies show that they may not consume minimum levels of Vitamin D for bone health either. Beyond that, emerging science suggests that optimal intake for health may exceed current Vitamin D advice for adequacy. Higher Vitamin D intake may help protect against many health problems such as diabetes, heart disease, some cancers and autoimmune diseases, including multiple sclerosis and rheumatoid arthritis.
Fortification is an appropriate strategy for addressing public health concerns about the Vitamin D shortfall when added to the right foods in the right amounts for the right target population.
Can the bakery industry partner in addressing Vitamin D inadequacy? The United States Food and Drug Administration regulations allow discretionary Vitamin D fortification of bakery foods. Yet with unknowns about health benefits, optimal intake and dietary guidance for Vitamin D, the bakery industry should proceed cautiously until more science-based Vitamin D guidance is available. Among the issues:
Ø Emerging science, pending recommendations. Except for bone health, scientific evidence on the health benefits of Vitamin D is inconclusive. Currently the Dietary Reference Intakes, established by American and Canadian scientists, provide only minimal, not optimal, advice for Vitamin D. Updated Vitamin D and calcium recommendations are scheduled for release from the Institute of Medicine in June. Although the U.S. Dietary Guidance Advisory Committee recognizes Vitamin D as a shortfall nutrient, new IOM recommendations may not be released in time for full consideration in the Dietary Guidelines for Americans 2010.
Ø Right bakery products for the targeted population. The bakery industry needs to determine whether baked foods are appropriate for Vitamin D fortification, and if so, which products are consumed by those at risk for Vitamin D deficiency. It's important to note that for bone health, Vitamin D works with calcium. While milk naturally contains significant amounts of other bone-building nutrients (calcium, phosphorus, magnesium), bakery goods do not. That said, milk is not the beverage of choice for all consumers. Except for fortified breakfast cereals in the United States, consumers don’t readily recognize grain products as sources of Vitamin D.
Ø Form of Vitamin D for fortification. Current U.S. labeling laws treat Vitamins D2 and D3 equivalently and interchangeably. As an additive, Vitamin D2 comes from plant-based sources whereas Vitamin D3 comes from animal-based sources. Both forms are approved for bakery products. Scientific evidence on the bioavailability of different forms of Vitamin D is not conclusive. Since Vitamin D and calcium work as partners in bone health, fortifying with appropriate levels of calcium should be considered when fortifying with Vitamin D.
Ø Vitamin D fortification levels. The FDA has set the fortification level for grain products, including bakery products, at ≤90 IU of Vitamin D per 100-gram serving from any source. For bread or a bakery roll, that is a maximum fortification level of 45 IU Vitamin D per 50-gram bread slice or roll.
Ø Among other fortification considerations:
1) In the future, the bakery industry may choose to establish a standard level for Vitamin D in specific bakery products (as done for fortified milk) to help consumers make decisions about Vitamin D-fortified foods.
2) Adding Vitamin D to flour allows control over fortification levels, noting varying product formulations among bakery products.
3) Vitamin D fortification in the total diet, including bakery products, should be considered to avoid adverse effects of excessive Vitamin D intake.
Ø U.S. labeling issues. If a product is Vitamin D fortified, Vitamin D must appear in the ingredient list and in the Nutrition Facts panel, shown as noted in food labeling regulations. If one label serving has at least 10% Daily Value, or 40 IU, the label also can carry a nutrient content claim as a “good source” of Vitamin D. The product name also must reflect the appropriate nutrient content claim and the appropriate standardized term for the product, such as "Vitamin D Fortified Enriched Bread."
Ø Also of note:
1) The current allowable level of Vitamin D in bakery products is not high enough to qualify a Vitamin D-fortified bakery product as an "excellent source" of Vitamin D. A product needs to have at least 20% DV of a given nutrient to be an "excellent source." For Vitamin D that would be 80 IU or more Vitamin D per label serving.
2) The Daily Values for Vitamin D, set by food labeling regulations, differ from the DRIs. Until labeling regulations change, the current DV for Vitamin D will remain at 400 IU even if the DRIs for Vitamin D change in 2010.
3) Although a health claim linking Vitamin D and calcium to bone health has been approved, bakery products cannot be fortified at levels high enough for Vitamin D and calcium to make this health claim.
Ø Marketing to consumers. An effective, science-based consumer information effort for Vitamin D overall and in Vitamin D-fortified bakery foods including label-reading and menu planning skills will be needed by the bakery industry in partnership with other nutrition education efforts.
Vitamin D Fortification: A Canadian Perspective
Fortification and labeling regulations in the United States differ from those in Canada.
Can the bakery industry partner in addressing Vitamin D inadequacy? Canadian regulations allow only limited voluntary Vitamin D fortification at this time. Bakery products are not identified in Canada's Food and Drug Regulations as a category for voluntary fortification. Without regulatory guidance, and with unknowns about the health benefits, optimal intake and dietary guidance for Vitamin D, the bakery industry should proceed cautiously. Among the issues:
Ø Emerging science, pending recommendations. In a 2007 statement, Health Canada recognized that significant evidence has emerged since the IOM established recommendations for Vitamin D in 1997, and is committed to working closely with the U.S. Department of Health and Human Services to determine how best to update the DRIs for Vitamin D.
Ø Need for regulatory support for Vitamin D fortification. The bakery industry needs to determine whether baked foods are appropriate for Vitamin D fortification. If so, it should play an appropriate role in supporting the issuance of Canadian regulations for the Vitamin D fortification of bakery foods. Among the considerations for setting fortification levels:
1) Specified levels of fortification should be based on current science-based recommendations for Vitamin D as well as calcium. For bone health, Vitamin D and calcium work together. (Currently Canada allows calcium fortification of some flours). While milk naturally contains significant amounts of other bone-building nutrients (calcium, phosphorus, magnesium), bakery foods do not. That said, milk is not the beverage of choice for all consumers.
2) The bakery industry may choose to establish a standard level (or range) for Vitamin D in specific bakery products (as done for fortified milk) to help consumers make decisions about Vitamin D-fortified foods.
3) Adding Vitamin D to flour allows control over fortification levels, noting variability of Vitamin D with product formulations among bakery products.
4) Vitamin D fortification in the total diet, including bakery products, should be considered to avoid adverse effects of excessive Vitamin D intake.
The IOM acknowledges that food fortification in Canada has been tightly regulated, but also notes that the situation is changing. The result may allow more options for discretionary fortification in the future.
Ø Form of Vitamin D for fortification. Current Canadian labeling laws treat vitamins D2 and D3 equivalently and interchangeably. As an additive, Vitamin D2 comes from plant-based sources whereas Vitamin D3 comes from animal-based sources. Scientific evidence on the bioavailability of different forms Vitamin D is not conclusive. Since Vitamin D and calcium work as partners in bone health, fortifying with appropriate levels of calcium should be considered when fortifying with Vitamin D.
Ø Canadian labeling issues. Canadian regulations, including labeling and fortification levels, have been established for foods that are Vitamin D fortified. Current regulations, however, do not include bakery foods. Unless adequate Vitamin D levels were provided by ingredients such as Vitamin D-fortified milk or margarine, bakery foods could not carry a nutrient content claim, a nutrient function claim or health claim related to Vitamin D. Labeling regulations in Canada differ from those in the Unites States.
Ø Marketing to consumers. An effective, science-based consumer information effort for Vitamin D overall and in Vitamin D-fortified bakery foods including label-reading and menu planning skills will be needed if Vitamin D fortification in bakery foods is allowed by the bakery industry in partnership with other nutrition education efforts. Currently consumers don’t recognize grain products as sources of Vitamin D.
Vitamin D Matters: Where Does the Bakery Industry Fit?
Vitamin D fortification may offer an opportunity for the bakery industry. Options should be weighed in context of the total diet along with science-based knowledge on Vitamin D such as what’s well known about Vitamin D’s role in health, its sources including fortified foods, emerging evidence on its health benefits and optimal intake, current intake recommendations, as well as pending updated advice and current regulations related to Vitamin D fortification and labeling.
Vitamin D 101: The Basics
Why is Vitamin D a current health concern? What is its role in human health? What foods provide this essential vitamin? How much is enough -- and too much? And what emerging science is shaping our understanding of Vitamin D’s health benefits?
Ø Ultraviolet light. Nicknamed the “sunshine vitamin,” Vitamin D's uniqueness lies in the body's ability to synthesize it. When ultraviolet light from sun penetrates bare skin, 7-dehydrocholesterol (a form of cholesterol) in the body converts to Vitamin D3 (cholecalciferol), which is a biologically inert form of Vitamin D.
Ø Unfortified foods. As a fat-soluble nutrient, Vitamin D3 occurs naturally but in limited supply. Only a few foods are good sources: oily fish such as salmon and mackerel, tuna packed in oil and fish oils. Beef liver, egg yolk and cheese contain much smaller amounts. Some mushrooms provide varying amounts of Vitamin D2 (ergocalciferol), another inert form of Vitamin D; a plant sterol (ergosterol) converts to Vitamin D when exposed to UV light. Vitamin D2 also is derived from yeast.
Ø Fortified foods. Because foods naturally rich in Vitamin D are limited, most Vitamin D in the U.S. diet comes from a handful of fortified foods such as Vitamin D-fortified milk and some other milk products (mostly yogurt and cheese), as well as calcium- and Vitamin D-fortified products, such as some fruit juices, juice drinks, soy products, meal replacement bars, infant formula, ready-to-eat cereals and breads. Since the 1930s in the United States and since the 1970s in Canada, most milk has been fortified with Vitamin D3 as a way to prevent children from developing rickets, a Vitamin D deficiency disease. The amount is standardized in the United States to 100 IU per 8-ounce and in Canada as 300-400 IU per Reasonable Daily Intake of milk (Reasonable Daily Intake is defined by regulation as 30 fl. oz., or 852 ml per day.) Both forms -- Vitamins D2 and D3 -- are used in fortification.
Ø Dietary supplements. In varying amounts, dietary supplements are another source, with Vitamin D generally provided as cholecaliciferol, or Vitamin D3.
With the growing interest in Vitamin D, the U.S. Department of Agriculture’s update of its USDA Nutrient Database for Standard Reference, Release 22, now includes Vitamin D values for about 3,000 foods. The update, released in October 2009, includes Vitamin D data (as IUs) for 20 species of fish and many Vitamin D-fortified foods. As available, values for both vitamins D2 and D3 (in micrograms) also were provided. For more information, go to www.ars.usda.gov/nutrientdata.
In Canada Vitamin D data is provided in the Canadian Nutrient File, showing micrograms of Vitamin D -- both reasonable portions and gram weights -- for about 1,850 foods. For more information, go to http://www.hc-sc.gc.ca/fn-an/nutrition/fiche-nutri-data/index-eng.php.
From Inert to Biologically-active Form
Through hydroxylation, both forms -- Vitamins D2 and D3 -- are converted in the liver to calcidiol, or 24(OH) Vitamin D, which circulates in the bloodstream. Circulating serum 24(OH) Vitamin D is used to measure an individual’s Vitamin D status; more research is needed to determine the appropriate level for optimum health.
Vitamin D becomes active when it converts from calcidiol to calcitriol (its metabolically active hormonal form) in the kidneys along with other tissues and body cells.
For Bone Health and Beyond
Vitamin D works in partnerships with other nutrients and hormones. As calcitriol, Vitamin D plays a key role in bone health. It enhances calcium and phosphorus absorption in the gut, keeps calcium and phosphate concentrations at a level needed for normal bone mineralization and promotes growth and bone remodeling. For children, that means proper bone formation; for adults, maintaining bone strength.
As a side note, calcium is absorbed in two ways – one requiring Vitamin D, the other, not. When Vitamin D intake is insufficient, one mechanism is compromised. To compensate, calcium intake needs to be higher to allow enough calcium absorption from the other mechanism, but how much? Most people do not consume enough calcium to meet that added demand – another reason to maintain adequate Vitamin D status.
A growing, yet inconclusive, body of evidence indicates broader roles for Vitamin D, which is independent of calcium absorption and of bone health. Research is mostly epidemiological; clinical studies are needed.
Ø As an important metabolite, calcitriol is a cellular essential. It helps regulate other body functions, including the production, growth and differentiation of body cells and the normal functioning of the immune system.
Ø Optimal Vitamin D status may offer protection from certain cancers. The links to lower colon cancer risk are strongest, but Vitamin D also may help protect against breast and prostate cancers.
Ø Other studies indicate links between Vitamin D status and heart health, blood pressure regulation, diabetes, glucose intolerance and autoimmune diseases, including multiple sclerosis, rheumatoid arthritis and Crohn’s disease.
How Much is Enough?
With adequate exposure to sunlight, the skin of healthy individuals can manufacture nearly all the Vitamin D needed. Yet, due to limited or irregular exposure to sunlight, even for healthy people, Vitamin D has been identified as an essential dietary nutrient in the U.S.
Dietary Reference Intakes for Vitamin D were established in 1997. The DRIs are a comprehensive set of nutrient reference values for healthy populations set by American and Canadian scientists with oversight by the Food and Nutrition Board, Institute of Medicine, an independent, non-governmental body in the United States. DRIs include Adequate Intake Levels, Recommended Dietary Allowances and Tolerable Upper Intake Levels.
Ø AIs for Vitamin D are minimum daily amounts needed by healthy people for bone health and calcium metabolism – and assume no sun exposure. Because Vitamin D metabolism declines with age, AIs for Vitamin D are higher for older adults, with recommendations increasing at age 51 and again at age 71.
Ø ULs are the maximum daily intake for Vitamin D that probably would not cause adverse health effects.
Ø Due to insufficient scientific evidence, no RDAs for Vitamin D were established in 1997. (The RDA is the average daily intake level adequate to meet the nutrient needs of nearly all healthy Americans.) Optimal intake levels for Vitamin D have not been determined.
A growing body of science-based evidence is expanding knowledge about the needs for and the roles and benefits of Vitamin D. A 2009 research review in the American Journal of Clinical Nutrition called for higher DRI levels for Vitamin D. Some experts advise a level closer to 1000 IU per day, much higher than current AIs. In its Guiding Principles for the Discretionary Addition of Nutrients to Foods, published in 2003, the IOM noted that AI levels in the current DRIs are not high enough for those who do not produce enough in their skin through sun exposure. By May, updated DRIs for Vitamin D, as well as calcium, are expected from the FNB/IOM.
In early 2009 the Dietary Guidelines Advisory Committee in the United States acknowledged that IOM's updated Vitamin D recommendations should be addressed in the Dietary Guidelines for Americans 2010, which is scheduled for release by USDA and HHS this fall. The November 2009 DGAC meeting reported a Vitamin D shortfall for adults and children based on a review of the scientific evidence and proposed that Vitamin D may be identified as a nutrient of concern for the 2010 guidelines. Since the IOM report will not be released until late spring, some speculate that there may not be enough time to fully address new Vitamin D recommendations within the 2010 Dietary Guidelines. In a 2007 statement, Health Canada recognized that significant evidence has emerged since the IOM established recommendations for Vitamin D in 1997, and is committed to working closely with the U.S. Department of Health and Human Services to determine how best to update the DRIs for Vitamin D.
In 2008 the American Academy of Pediatrics established higher recommendations for Vitamin D for healthy children and adolescents: 400 IUs daily -- twice the AI level set by the FNB in 1997. The AAP advises a daily Vitamin D supplement for those who do not consume 400 IU of Vitamin D daily from milk and other food. After reviewing evidence on widespread Vitamin D and calcium deficiency throughout the world and the United States, especially among those ages 50 years and above, the National Osteoporosis Foundation updated its Vitamin D recommendations in 2008. It advises adults under age 50 to consume 400 to 800 IU Vitamin D daily, and adults age 50 and older, 800–1,000 IU Vitamin D daily. NOF identifies both food and supplement sources. For supplements, it notes that recent studies show that Vitamins D3 and D2 are equally good for bone health.
Health Canada (Santé Canada) provides Vitamin D recommendations until the DRIs are updated (in 2010):
Ø To prevent rickets, all breastfed, healthy-term babies should receive a daily Vitamin D supplement of 400 IU from birth until the diet (food) can provide 400 IU per day or until breastfed infants are one year of age. Formula-fed infants should consume Vitamin D-fortified formula.
Ø After one year, children should consume 200 IU Vitamin Daily, which is provided in two cups of milk or Vitamin D-fortified soy beverage.
Ø Canadians over two years of age, including pregnant and lactating women, are urged to consume two cups of milk or Vitamin D fortified soy beverage, which will supply 200 IU per day.
Ø Adults age 50 years and over are advised additionally to take a daily Vitamin D supplement of 10 micrograms (400 IUs) since the food pattern in Canada's Food Guide does not provide enough Vitamin D to meet the AI established by the IOM.
While some organizations in Canada including the Canadian Cancer Society have issued increased recommendations for Vitamin D, Health Canada believes these recommendations are premature and that more research review is needed on the benefits and safety of higher Vitamin D levels before revising its recommendations for Canadians.
To reduce the risk of certain cancers, the Canadian Cancer Society recommends:
1) Adults living in Canada should consider taking Vitamin D supplementation of 1,000 IUs daily during the fall and winter.
2) Adults at higher risk (who are older, with dark skin, who don't go outside often, who wear clothing that covers most of their skin) of lower Vitamin D levels should consider taking Vitamin D supplements with 1,000 IU per day all year round.
Despite its availability, Vitamin D often comes up short. Vitamin D status is determined with biological indicators; since the DRI for Vitamin D is an Adequate Intake level, calculating the prevalence of Vitamin D inadequacy with this reference value is not possible, notes IOM.
A Vitamin D deficiency can lead to health problems, especially related to bone health. Among some groups of children, the incidence of rickets is resurging. With rickets, bones do not mineralize adequately causing soft bones and skeletal deformities. Among adults, Vitamin D deficiency is often undetected for years, even as it leads to osteomalacia, which is characterized by weakened muscles, weak bones and perhaps bone pain. In the long run this contributes to osteoporosis later in life. In the United States, 10 million Americans currently are estimated to have osteoporosis, according the National Osteoporosis Foundation, with 34 million more at risk due to low bone mass. Approximately 1.4 million Canadians are affected by osteoporosis, according to statistics reported by the International Osteoporosis Foundation.
Research also indicates that Vitamin D deficiency during pregnancy is linked adversely to infant development.
Vitamin D deficiencies have multiple causes, among them:
Ø Low intake of dietary Vitamin D over time. Those who limit or avoid Vitamin D-fortified milk due to a milk allergy, lactose intolerance, a vegan diet, cultural food practices or a preference for other beverages such as soft drinks are often at risk.
Ø Limited exposure to direct sunlight. This often results from indoor life-and work-styles, living at latitudes with less winter sunlight such as the northern United States and throughout Canada, being homebound for health reasons, clothing that covers much of the skin, and heavy use of sunscreen. Those with dark skin also are at higher risk; the pigment melanin reduces the skin’s ability to produce Vitamin D.
Ø Aging. With age, skin does not synthesize Vitamin D as efficiently. Kidneys do not convert Vitamin D to its active form as efficiently either.
Ø Fat malabsorption. Because Vitamin D is fat soluble, fat malabsorption also is linked to health problems such as Crohn’s disease, cystic fibrosis and liver disease. Those who have had part of their upper small intestine surgically removed are also at greater risk. Vitamin D is absorbed in this part of the digestive tract.
Currently there is no consensus on optimal Vitamin D status. As a result, the number of people who are vitamin-D deficient has not been determined. The USDA Agriculture Research Service estimates that a significant percentage of Americans may consume less dietary Vitamin D than considered adequate (AI) in the 1997 DRIs.
Statistics Canada, in partnership with Health Canada and the Public Health Agency of Canada, is conducting the Canadian Health Measure Survey, which will provide the first national data on the Vitamin D status of Canadians in over 35 years. A full report will be released in 2010. Preliminary data from 5,500 Canadians was released in July 2009 for use in developing updated IOM recommendations for Vitamin D.
While necessary for health, dietary Vitamin D in large doses can pose health risks, among the symptoms: constipation, nausea, vomiting, poor appetite and weight loss. Because of its role in calcium absorption, Vitamin D toxicity also can raise blood levels of calcium, causing mental confusion, irregular heart rhythms or kidney stones. A high intake of Vitamin D from supplements would be the likely cause. Excessive exposure to sunlight does not cause Vitamin D toxicity.
Vitamin D Fortification: Current Regulations in the United States
Two forms of Vitamin D are used to fortify foods. As an additive, Vitamin D is “generally recognized as safe” (GRAS) by the U.S. Food and Drug Administration for both the crystalline and resin Vitamin D2 and Vitamin D3 in most foods. Vitamin D3 is more commonly used in fortification. Based on current scientific evidence, FDA views the two forms as equivalent.
For Vitamin D fortification, FDA allows the following in food and beverages:
Ø Crystalline Vitamin D2, also known as ergocalciferol. It is produced by ultraviolet irradiation of ergosterol isolated from yeast and related fungi and is purified by crystallization. Being plant based, this form is appropriate in foods, such as soy milk for strict vegetarians.
Ø Crystalline Vitamin D3, also known as cholecalciferol. Isolated from fish-liver oils, it is manufactured by ultraviolet irradiation of 7-dehydrocholesterol produced from cholesterol and is purified by crystallization. This form of Vitamin D also is produced endogenously in humans through sunlight activation of 7-dehydrocholesterol in the skin.
Ø Vitamins D2 and D3 resin. These are concentrated forms of irradiated D2 and D3 and separated from the reacting materials noted above. They are sold as food sources of Vitamin D without purification. The crystalline form is more commonly used in fortification today.
The FDA regulates maximum levels for Vitamin D fortification for specific categories of food. Vitamin D ingredients can be used as the sole source of added Vitamin D within limits.
In May 2009, the U.S. FDA approved Vitamin D fortification with crystalline Vitamin D2 of soy-based foods and drinks: in soy beverages, soy beverage products, soy-based butter substitute spreads, soy-based cheese substitutes, and soy-based cheese substitute products. Vitamin D2 from plant sources is appropriate in soy products for vegans.
In addition, some other food and beverage products are approved for Vitamin D3 fortification, including infant formula, margarine, calcium-fortified fruit juices and fruit juice drinks, meal replacement bars and other bars, and soy protein-based meal replacement beverages, all positioned for maintaining body weight; and cheese and cheese products with some exclusions.
Vitamin D information is mandatory or voluntary on food labels and presented in the following ways:
Ø Nutrition Facts. Unless fortified with Vitamin D or carrying a nutrient content claim on the label, Nutrition Facts on food labels are not required to provide Vitamin D content. As a result, consumers are likely more aware of Vitamin D in fortified foods than in foods with naturally occurring Vitamin D.
When fortified with Vitamin D, however, this vitamin must be included in the Nutrition Facts panel by FDA regulation. The amount of Vitamin D is listed as % Daily Value (%DV) for a standardized reference amount (label serving size), established by FDA’s Food Labeling Guidance & Regulatory Information. (The Daily Value, which reflects the Reference Daily Intake, for Vitamin D is 400 IUs for those ages 4 years and older. The Daily Value used in labeling in Canada is 5 micrograms, comparable to 200 IUs, for those ages 2 years and older.)
With growing interest in Vitamin D and the recent update of the USDA Nutrient Database to include more Vitamin D values, foods with naturally occurring Vitamin D, such as more fish species and mushrooms, may voluntarily include this information on the Nutrition Facts panel.
Ø Ingredient list. Vitamin D additives must be listed on the label's ingredient list, as well as the Nutrition Facts panel, according to FDA regulations.
Ø Nutrient content claim. The food package may carry a nutrient content claim for Vitamin D on the food package if it meets criteria, noted in FDA’s Guidance for Industry: A Food Labeling Guide. According to current levels for Daily Values, a food may be listed as:
· A “good source of Vitamin D” if the food contains 10-19% of the Daily Value (40 to 76 IUs per label serving); if it meets this criterion, the terms “contains” and “provides” can also be used. A nutrient included in a nutrient content claim must also be listed in the Nutrition Facts panel.
· “High in” Vitamin D if it contains at least 20% of the Daily Value (80 IUs or more per label serving); if it meets this criterion, the terms “excellent source of” or “rich in” may also be used. Bakery products cannot labeled as an “excellent source” since the amount of Vitamin D (80 IU Vitamin D per reference amount for labeling) for this claim would exceed the maximum level allowed for Vitamin D fortification of grain products.
Ø Health claim. Under a 2008 ruling, noted in Guidance for Industry: Food Labeling: Health Claims; Calcium and Osteoporosis, and Calcium, Vitamin D, and Osteoporosis, the U.S. Food and Drug Administration, has approved a health claim that communicates the benefits of calcium and Vitamin D to bone health -- if the claim:
· Clearly states that adequate calcium and Vitamin D intake throughout life, as part of a healthful diet, is essential to reducing osteoporosis risk.
· Does not imply that inadequate calcium and Vitamin D intake is the only recognized osteoporosis risk factor.
· Does not attribute any reduction in osteoporosis risk to maintaining an adequate dietary calcium and Vitamin D intake throughout life.
To make this claim, the food must be rich in both calcium and Vitamin D, providing at least 200 milligrams of calcium and 80 IUs of Vitamin D (for standardized reference amounts). Among other requirements, calcium must be in a digestible form. Because no foods naturally contain these nutrients at these levels, only fortified foods would qualify for this claim.
Optionally, this health claim may carry other information: the link between physical activity and reduced risk for osteoporosis; the role of adequate calcium and Vitamin D intake throughout life and its link to the reduced risk of osteoporosis by optimizing peak bone mass during adolescence and early adulthood; the link to reduced risk of osteoporosis through the mechanism of slowing the rate of bone loss for persons with a family history of the disease, post-menopausal women, and elderly men and women; and the number of people in the United States, including people in certain subpopulations, who have osteoporosis or low bone density when the current information source (National Center for Health Statistics, National Institutes of Health, or National Osteoporosis Foundation) is noted.
According to FDA, the claim on foods that are excellent sources of both calcium and Vitamin D might read: "Adequate calcium and Vitamin D throughout life, as part of a well-balanced diet, may reduce the risk of osteoporosis," or "Adequate calcium and Vitamin D throughout life, along with physical activity, may reduce the risk of osteoporosis in later life."
Ø Product name. When Vitamin D-fortified, the name of baked goods must reflect the appropriate nutrient content claim and the appropriate standardized term for the product, such as "Vitamin D Fortified Enriched Bread."
Vitamin D Fortification: Current Regulations in Canada
Two forms of Vitamin D are used to fortify foods.
Ø Crystalline Vitamin D2, also known as ergocalciferol. It is produced by ultraviolet irradiation of ergosterol isolated from yeast and related fungi and is purified by crystallization. Being plant based, this form is appropriate in foods, such as soy milk, for strict vegetarians.
Ø Crystalline Vitamin D3, also known as cholecalciferol. Isolated from fish-liver oils, it is manufactured by ultraviolet irradiation of 7-dehydrocholesterol produced from cholesterol and is purified by crystallization. This form of Vitamin D also is produced endogenously in humans through sunlight activation of 7-dehydrocholesterol in the skin.
Ø Vitamins D2 and D3 resin. These are concentrated forms of irradiated D2 and D3 and separated from the reacting materials noted above. They are sold as food sources of Vitamin D without purification. The crystalline form is more commonly used for fortification.
As of December 2007, nutrition labeling became mandatory in Canada for all prepackaged foods.
Ø Nutrition Facts table. By Canadian Food Inspection Agency regulation, Vitamin D must be included in the Nutrition Facts when the food label (including the ingredient list or any advertisement) carries any mention, statement, claim, etc., about Vitamin D. Vitamin D also must be declared when shown as a component of one of the ingredients (except flour) of a prepackaged product. As a result, consumers are likely more aware of Vitamin D in fortified foods or foods with Vitamin D-related claims, than in foods with naturally occurring Vitamin D.
The amount of Vitamin D is a combined total of both the naturally occurring and added Vitamin D in a food. Formerly expressed in International Units (IU), Vitamin D is measured in micrograms (µg) with 1 microgram (µg) of either ergocalciferol (Vitamin D2) or cholecalciferol (Vitamin D3) being equal to 40 IU Vitamin D.
· Stated as "Vitamin D" or "Vitamin D," the amount is percentage of the Daily Value (DV) per stated serving size. The amount may be rounded when less than 2% DV -- if the product contains less than 1% of the Daily Value per reference amount and per serving of stated size , to "0 %", and in all other cases, to the nearest multiple of 2%; when 2% to 10% DV, to the nearest multiple of 2%; when 10% to 50% DV to the nearest multiple of 5%, and 4) when more than 50% DV to the nearest multiple of 10%.
· The amount of Vitamin D in the Nutrition Facts is listed as % Daily Value (%DV) for the stated label serving size, noted in the Guide. (The Daily Value in Canada for Vitamin D is 5 micrograms (µg) per day for those ages two years and older; for those less than two years, it is 10 µg per day.) The Daily Value, which is synonymous with Recommended Daily Intake (RDI) in Canada for vitamins and mineral nutrients, is a reference amount used in labeling. Table 7 contains IU of Vitamin D converted to µg, along with a calculation of the % Daily Value (Canadian) of Vitamin D for adults and children.
Note: The Daily Values for Canada differ from those in the United States. In Canada, the % DV are based on the 1983 Recommended Daily Intakes for Canadians, while in the U.S. they are based on the 1968 U.S. Reference Daily Intakes. In the U.S. the Daily Value for Vitamin D is 400 IUs, which is comparable to 10 µg, for those ages 4 years and older.
· Serving sizes in Canada's Guide to Food Labeling and Advertising are usually presented as a range. This allows manufacturers some flexibility for products of varying density and size, such as cookies or slices of bread. To avoid misleading consumers, the same serving size should be used whenever a serving size is mentioned on the label, e.g. in the Nutrition Facts table, the directions for use, etc.
Ø Ingredient list. For prepackaged foods approved for Vitamin D fortification, Vitamin D must be listed at the end of the ingredient list, in any order with spices, seasonings and herbs (except salt), natural and artificial flavors, flavor enhancers, food additives, and other vitamin and mineral nutrients and their derivatives or salts. The ingredient list must be shown in both English and French unless exempted by the Food and Drug Regulations [B.01.012].
Current regulations do not allow Vitamin D fortification of bakery products. As a result, Vitamin D would not appear as a nutritive additive in the ingredient list.
Ø Nutrient content claim. The food package may carry a nutrient content claim for Vitamin D on the food package if it meets criteria, noted in Canada's Guide to Food Labeling and Advertising. A nutrient included in a nutrient content claim must also be listed in the Nutrition Facts panel. According to current levels for Daily Values, a food may be noted as (see Table 8):
· "Contains" or "source of" Vitamin D if the food contains 5% DV (RDI) or more for Vitamin D per stated label serving.
· A “good source of" or "high in" Vitamin D if the food contains 15% or more of the Daily Value (RDI) for Vitamin D per stated label serving.
· "Excellent source of," "very high in," or "rich in" Vitamin D if it contains 25% or more of the Daily Value (RDI) for Vitamin D per stated label serving.
Current regulations do not allow Vitamin D fortification of bakery products. Unless enough Vitamin D comes from Vitamin D-fortified ingredients, such as milk or margarine, Vitamin D levels are likely inadequate in most bakery foods to carry a nutrient content claim for Vitamin D.
Ø Nutrient function claim. This type of claim, formerly called biological role claims, describes the well-established roles of energy or known nutrients, essential for maintaining good health or normal growth and development. Two nutrition function claims are acceptable for Vitamin D:
· factor in the formation and maintenance of bones and teeth
· enhances calcium and phosphorus absorption and utilization
To carry this claim, the product must have at least 5% of the RDI (or DV), or 0.25 µg, for Vitamin D. The claim must be in English and French, unless exempted from bilingual labeling.
Ø Health claim. Since 2003, Health Canada has allowed a health claim (as a disease risk reduction claim) on food labels or in advertisements, noting that a healthy diet with adequate calcium and Vitamin D, along with regular physical activity, is linked to a reduced risk of osteoporosis.
Current regulations do not allow Vitamin D fortification of bakery foods. As a result most won't contain adequate levels of Vitamin D to qualify for a health claim linking Vitamin D, calcium, and bone health -- unless adequate amounts of these nutrients come from Vitamin D-fortified ingredients such as margarine and milk.
Ø Wording. The health claim must be worded exactly as follows. It cannot be modified and no intervening information, graphic sign or symbol may come between parts of the claim. However, words, numbers, signs or symbols may come before or after the health claim, provided that they do not change the nature of the claim. And in the case of advertisements, all parts of the claim must be displayed in equal prominence with no parts highlighted."
(1) "A healthy diet with adequate calcium and Vitamin D, and regular physical activity, help to achieve strong bones and may reduce the risk of osteoporosis. (Naming the food) is a good source of calcium."
(2) "A healthy diet with adequate calcium and Vitamin D, and regular physical activity, help to achieve strong bones and may reduce the risk of osteoporosis. (Naming the food) is high in calcium."
(3) "A healthy diet with adequate calcium and Vitamin D, and regular physical activity, help to achieve strong bones and may reduce the risk of osteoporosis. (Naming the food) is an excellent source of calcium."
(4) "A healthy diet with adequate calcium and Vitamin D, and regular physical activity, help to achieve strong bones and may reduce the risk of osteoporosis. (Naming the food) is very high in calcium."
(5) "A healthy diet with adequate calcium and Vitamin D, and regular physical activity, help to achieve strong bones and may reduce the risk of osteoporosis. (Naming the food) is an excellent source of calcium and Vitamin D."
(6) "A healthy diet with adequate calcium and Vitamin D, and regular physical activity, help to achieve strong bones and may reduce the risk of osteoporosis. (Naming the food) is very high in calcium and Vitamin D."
Ø Conditions for the health claim. If a product carries a health claim or statement for Vitamin D on the label or in the advertisement, by or on the direction of the manufacturer of the product. The Nutrition Facts table on the label will include the amount of Vitamin D and phosphorus, in accordance with item 14 of Table 6-2 [B.01.402(2)] of the Guide, and the label or advertisement will include the amount of Vitamin D, calcium and phosphorus per serving of the stated size, in accordance with section B.01.602, if applicable, of the Guide.
The product may carry one of the six health claims noted above, if it meets certain nutritional criteria. Only claims (5) and (6) require a specified Vitamin D level. The product must contain 200 mg or more calcium for claims (1) and (2); the product must contain 275 mg or more calcium for claims (3) and (4); and the product must contain 275 mg or more calcium and 1.25 µg or more of Vitamin D for claims (5) and (6). Calcium amounts are somewhat higher if the product is a prepackaged meal. It also cannot contain more phosphorus (except from phytate) than calcium and must contain 0.5% or less alcohol.
· Language. Disease risk reduction claims on a label must be given in both English and French unless the food is a "local food", a "test market food", or a "specialty food," as defined in the Food and Drug Regulations. In that case, the mandatory information only needs to be shown in one of those languages.
Vitamin D Fortification: An Opportunity for the Bakery Industry?
Fortification offers an appropriate strategy for addressing the public health concerns about the Vitamin D shortfall when added to the right foods in the right amounts for the right target population. The US Food and Drug Administration Fortification Policy and Institute of Medicine’s Guiding Principles for Nutrition Labeling and Fortification 2003, provides guidance for appropriate fortification. Unlike folic acid fortification in grain products, Vitamin D fortification is discretionary.
Vitamin D fortification is a likely opportunity for many categories within the food industry, including the bakery industry. "Bread could be a suitable vehicle for fortification because it is a common part of diets worldwide," noted Natri et al. in the Journal of Nutrition, 2006. (Their research showed the bioavailability and stability of Vitamin D3, evenly distributed in fortified wheat and rye breads, despite differences in the fiber content of the breads; fortification levels in the study were higher than US fortification regulations allow.)
In its 2003 report on fortification IOM noted, “Recent studies demonstrated that the levels of Vitamin D already added to food are not high enough or are not found in enough different food products to prevent Vitamin D inadequacy.” Since then, more Vitamin D-fortified products have entered the marketplace, especially in the United States.
While fortification may be scientifically justified, however, many experts believe that more scientific investigation and answers on Vitamin D status and optimal intake levels are needed before the food industry rushes to fortify. That includes consensus on appropriate fortification in all categories of food, including bakery products. To fortify and market appropriately, many issues require consideration, among them:
The links among Vitamin D, calcium, and bone health are well documented, but scientific evidence on other health benefits for Vitamin D is not yet conclusive.
That said the U.S. FDA has only approved a health claim for calcium and Vitamin D related to bone health. As currently established, bakery products are not fortified for Vitamin D and calcium at levels high enough for this health claim. Other possible benefits of Vitamin D need to be communicated and/or marketed within the context of emerging science – and not as a health claim at this time.
In Canada the only approved Vitamin D-related health claim links a healthy diet with adequate calcium and Vitamin D, and regular physical activity with strong bones and reduced risk of osteoporosis. Two nutrient function claims are allowed for Vitamin D. Optimal intakes for Vitamin D have not been established, although evidence shows that Vitamin D status is inadequate for many. No RDAs currently exist – only AIs. Vitamin D fortification for bakery products, and all food categories, should be scientifically justified, based on documented public health needs and the documented prevalence of nutritional inadequacy in the population.
Updated DRIs for calcium and Vitamin D from the IOM, due for release in late June, may offer increased recommendations, pending adequate scientific evidence. (Some experts suggest that Vitamin D focus should include more emphasis on appropriate and safe exposure to sunlight.)
Ø Vitamin D fortification across many food categories could potentially result in excessive intake levels. Discretionary Vitamin D fortification for all food categories, including bakery products, needs to be considered in relation to current dietary intake of Vitamin D, the ULs (which may be updated/increased in 2010), and potential adverse effects of excessive Vitamin D intake.
Ø Vitamin D recommendations within the Dietary Guidelines for Americans 20I0 is not certain. The report from the Dietary Guidance Advisory Committee is scheduled for submission to USHHS and USDA in the spring before new DRIs are released. This potentially limits the marketing opportunity for science-based messaging related to Vitamin D.
Ø For the United States, until new labeling regulations are established, the Daily Values for Vitamin D will remain at 400 IU – and will not reflect possible changes in the DRIs. Regardless, Daily Values are reference values and not nutrient intake recommendations. The DV of 400 IU for Vitamin D is twice the AI level set by the FNB in 1997 for those ages 1 to 50 years; that level matches the current AI for adults ages 51 to 70, and the 2008 recommendations from the AAP for healthy children and adolescents.
Daily Values in Canada are lower, comparable to 200 IU for ages 2 years and above, than in the United States.
Ø Revised DRI levels could potentially -- and eventually -- impact regulatory levels for Vitamin D fortification and label claims in both the U.S. and Canada.
Currently in the United States, maximum levels for grain products, including bakery products, are set by U.S. FDA at 90 IU of Vitamin D per 100 grams (or about 3.5 ounces) as served. Reference amounts used for labeling vary for different bakery products. These levels of Vitamin D fortification, shown in Table 9, are allowed for these bakery products:
If one label serving has at least 10% DV, or 40 IU, a bakery product can be labeled as a “good source” of Vitamin D. As noted earlier, bakery products cannot be labeled as an “excellent source” since the amount of Vitamin D needed (80 IU Vitamin D per label serving) for this claim would exceed the maximum level for Vitamin D fortification of grain products allowed.
The FDA also provides regulations for Vitamin D fortification of enriched cornmeal and enriched farina, noted in the Electronic Code of Federal Regulations e-CFR, Title 21: Food and Drugs. Part 137 Cereal Flours and Related Products.
Ø In Canada grain products, including bakery products, are not identified in the Regulations Respecting Food and Drugs as a food category that can be voluntarily fortified with Vitamin D. However, the IOM acknowledges that food fortification in Canada has been tightly regulated, but also notes that the situation is changing. The result may be more options for discretionary fortification in the future
Ø In addition, the bakery industry needs to determine whether baked foods are appropriate for discretionary Vitamin D fortification -- and if so, which products. Milk is an appropriate food for Vitamin D fortification because it naturally contains significant amounts of bone-building nutrients (calcium, phosphorus, magnesium); bakery goods do not. Except for fortified breakfast cereals in the United States, grain products are not readily recognized as sources of Vitamin D.
Ø If Vitamin D fortification moves forward in the bakery industry, manufacturers must also consider:
· Form of Vitamin D. Current labeling laws treat Vitamins D2 and D3 equivalently and interchangeably; both forms are approved in the United States for bakery products. While Vitamin D3 often noted as more bio-available, scientific evidence on bioavailability of one form over another is not conclusive. Either form as a crystalline may be more cost effective than Vitamin D in a resin.
· Standardizing Vitamin D fortification levels in various bakery foods, as the dairy industry has done for milk. The U.S. FDA allows a range of Vitamin D fortification: equal to or less than 90 IUs of Vitamin D per 100 grams of bakery product. Standardized levels for specific products may help consumers make comparisons and decisions about Vitamin D-fortified foods. If fortification is allowable in bakery products in Canada, the same would be true.
· A fortification process that allows for controlled levels of Vitamin D. Adding Vitamin D to flour allows control, as product formulations vary among bakery products.
· Determination of the right bakery products for the targeted population. For example, are Vitamin D-fortified bread and bakery products appropriate and approved as school breakfast and lunch items, or are bakery products approved for the Women, Infants and Children Program in the United States? How does the gluten-free movement impact the consumption and types of bakery products? What bakery products are more often consumed by older adults and by cultural groups at risk for lower Vitamin D status? Fortifying with appropriate levels of calcium, as well as Vitamin D. Vitamin D and calcium work as partners in bone health.
Ø Consumers need science-based guidance on Vitamin D including how to use food labeling to identify, compare and choose Vitamin D-fortified foods and how to incorporate these foods into an eating plan. While U.S. consumers are increasingly aware of Vitamin D and bone health (as noted by the IFIC Functional Foods/Foods for Health Consumer Trending Survey, 2009), Vitamin D in today’s media can lead to confusion about appropriate intake levels and health benefits. Often single studies about Vitamin D provide health headlines, even though evidence-based advice is not yet available. If the bakery industry contributes significantly to discretionary Vitamin D fortification, an effective, science-based consumer information effort for Vitamin D fortification related to bakery foods will be needed by the bakery industry in partnership with other nutrition education efforts.
Bottom line: Vitamin D fortification can play a substantial role in addressing public health concerns about Vitamin D status. Regulations are in place for discretionary Vitamin D fortification of bakery foods in the U.S., but not in Canada. Yet with many unknowns, the bakery industry is wise to proceed with caution until more science-based guidance is released. Standardized Vitamin D levels can contribute to decisions about fortified products. Evidence-based consumer marketing and communication messages about Vitamin D will be an essential part of fortification initiatives.
Editor's Note: This white paper was supplied by AB Mauri Fleischmann's, Chesterfield, Mo.
Vitamin D Matters: Where Does the Bakery Industry Fit?
March 8, 2010