Scientific studies published this year have linked vitamin D intake to potential benefits in bone health, heart health, reducing the risk of breast cancer and reducing the risk of Parkinson’s disease.
"It’s the hottest area of research in nutrition," said Dr. Connie Weaver, Ph.D., professor of foods and nutrition at Purdue University in West Lafayette, Ind. "That kind of excitement generates more grants. There will be even more research projects."
A nutrition board eventually may increase the adequate intake (A.I.) levels of vitamin D, but the ruling may take a year or two, she added.
Dr. Weaver in 1997 was on the Food and Nutrition Board of the Institute of Medicine, which is part of the National Academy of Sciences. That board set A.I. levels of vitamin D ranging from 200 International Units (I.U.) to 600 I.U., depending on a person’s age. Tolerable Upper Intake Levels (U.L.) ranged from 1,000 to 2,000 I.U.
Nominations for panelists on the next Food and Nutrition Board are being taken now, Dr. Weaver said. Recent science gives credence to the view that both the A.I. and U.L. levels of vitamin D should increase. However, it might take a year and a half to two years for the Food and Nutrition Board to release new guidance levels, Dr. Weaver said.
She said food and beverage companies may need to wait on increasing the amount of vitamin D fortification in some products until the U.L. moves up from 2,000 I.U.
"They can’t do much until the upper level goes up," she said. "It’s equally important for the upper level to change for fortification to occur. There is such a gap between what the upper levels are and what the new dose-response studies say are toxic."
Dr. Weaver also would like to see a Recommended Dietary Allowance (R.D.A.) for vitamin D instead of an A.I. The R.D.A. implies scientists have more evidence for their ruling, she said.
"It will be interesting to see if they are more comfortable with an R.D.A. now," she said.
The American Academy of Pediatrics on Oct. 13 recommended all children receive 400 I.U. of vitamin D daily, up from its previous recommendation of 200 I.U. Dr. Weaver said this recommendation may have little influence on the Food and Nutrition Board, which will examine its own scientific evidence.
"There is very little data on children of any ages," she said.
Dr. Weaver said she did not want to speculate on any future A.I., U.L. or R.D.A. levels for vitamin D because she does not know what scientific evidence the Food and Nutrition Board will examine.
Dairy products remain a good avenue for vitamin D fortification with milk generally offering 100 I.U. per cup, Dr. Weaver said. Cereals and some baked foods also have vitamin D fortification.
"It’s generally like 40 I.U. or less in a serving, so that’s pretty small," Dr. Weaver said.
Lallemand, Montreal, now offers Eagle VitaD yeast with high levels of vitamin D. The yeast may be used to fortify bread, a staple item.
"It’s a good idea to have a staple fortified," Dr. Weaver said.
A fall flurry of Vitamin D research
Several scientific articles published this fall stuck to one theme — Increasing vitamin D intake may improve the health of humans:
• The article "Serum 25-Hydroxyvitamin D Concentrations and Risk for Hip Fractures" appeared in the Aug. 19 issue of the Annals of Internal Medicine. The study followed 800 women from the ages of 50 to 79 for a median of 7.1 years and found that women with hip fractures had lower levels of vitamin D.
• The article "Vitamin D Deficiency Increases Mortality Risk" appeared Aug. 20 in the Archives of Internal Medicine. Researchers from John Hopkins University analyzed vitamin D levels in 13,331 healthy men and women by using data from the third National Health and Nutritional Examination Survey (NHANES III) for nearly nine years. Of the 1,806 documented deaths in that time, 777 were related directly to some form of cardiovascular disease, with 400 of those being deficient in vitamin D. The results suggest all men and women concerned about their health should monitor blood pressure levels of vitamin D more closely.
• The article "Vitamin D From Dietary Intake and Sunlight Exposure and the Risk of Hormone-Receptor-Defined Breast Cancer" appeared on-line Aug. 27 in the American Journal of Epidemiology. The study considered 759 cases and 1,135 controls from a case control study in Ontario and suggested vitamin D is associated with a reduced risk of breast cancer.
• The Food and Drug Administration on Sept. 29 said it had amended its osteoporosis risk reduction health claim to reflect the importance of vitamin D, in combination with calcium, in promoting long-term bone health. The F.D.A. authorized the health claim, "Adequate calcium and vitamin D throughout life, as part of a well-balanced diet, may reduce the risk of osteoporosis."
• The article "Prevalence of Vitamin D Insufficiency in Patients With Parkinson Disease and Alzheimer Disease" appeared in the October issue of Archives of Neurology. Researchers from Emory University School of Medicine in Atlanta found significantly more patients with Parkinson’s disease had insufficient vitamin D levels than patients in a control group or patients with Alzheimer’s disease. The researchers concluded the data support a possible role of vitamin D insufficiency in Parkinson’s disease but further studies are needed to determine contributing factors.
• The American Academy of Pediatrics on Oct. 13 announced it was doubling the amount of recommended vitamin D for infants, children and adolescents. The clinical report "Prevention of Rickets and Vitamin D Deficiency in Infants, Children and Adolescents" recommended all children receive 400 International Units (I.U.) of vitamin D daily, up from 200 I.U.
Studies link vitamin K2 to bone, heart health
Proponents of vitamin K2 point to its ability to guide another important nutrient. It directs calcium away from arteries and into bones, thus providing benefits in both heart health and bone health, they say.
Opportunities to use vitamin K2 in processed foods improved earlier this year. An independent panel gave self-affirmed Generally Recognized As Safe (GRAS) status to MenaQ7 natural vitamin K2 for use as an ingredient in food products. P.L. Thomas, Morristown, N.J., distributes MenaQ7 in alliance with Norway-based NattoPharma, the owner of the brand.
Blue California, Rancho Santa Margarita, Calif., also offers natural vitamin K2 (menaquinone). The company said its vitamin K2 allows protein to bind to calcium and deposit it in bone cells rather than in soft tissue that may cause calcification of arteries and other health problems. Produced by a natural fermentation process, Blue California’s vitamin K2 is ideal for use in dietary supplements, according to the company.
Vitamin K2 is found in fermented cheese, curd and a fermented soy called natto, said Dr. Leon J. Schurgers, Ph.D., a senior researcher at the University of Maastricht in The Netherlands. He also is vice-president at VitaK, Inc., a wholly-owned company of the University of Maastricht Holding Co. Vitamin K1 differs from vitamin K2 in that it is found in leafy green vegetables and is used by the liver, where it is involved in the synthesis of blood clotting factors, Dr. Schurgers said.
Vitamin K2 fortification in American process cheese makes sense because process cheese is not fermented, according to P.L. Thomas. Functional beverages and foods and other dairy products also are potential applications.
Several published scientific studies, including at least two this year, have examined vitamin K2’s health benefits.
Dr. Schurgers was an author for an article appearing in the British Journal of Nutrition. Researchers followed 307 healthy children with an average age of 11.2 years over a two-year period. They found improving the status of the K vitamins resulted in improved bone mass.
"Numerous population studies and interventional trials have established the consumption of K vitamins to bone strength, structure and the reduction of the risk of fracture," Dr. Schurgers said. "This is due to the need to activate the vitamin-K dependent protein osteocalcin, which is essential for the body to utilize calcium in a healthy bone tissue.
"Unfortunately, most people, including children, are likely deficient in the K vitamins related to the need for bone health."
Another study published on-line Aug. 26 in the journal Athesclerosis involved 564 post-menopausal women. The study concluded high dietary menaquinone intake is associated with reduced coronary calcification.
This article can also be found in the digital edition of Food Business News, November 11, 2008, starting on Page 27. Click