by Jennifer Schraag
References
Vitamins play an important role in preventing dysfunction within the body. Today’s declining availability of nutrients through the food supply makes supplementation more important than ever. Retailers must arm themselves with the information consumers need to live long, healthy lives.
Vitamins are a group of carbon-comprised organic chemical compounds essential for growth and development, normal metabolism and regulation of cell function.1 Each vitamin has specific functions and inadequacy or deficiency of any one of them can result in numerous health problems and diseases.
Vitamins can be divided into two groups: water-soluble and fat-soluble.
Water-soluble
(hydrophilic) vitamins dissolve in water. Toxic doses of water-soluble vitamins are unlikely because excess intake is excreted through urination. Watersoluble vitamins cannot be stored in the body, so they must be replenished with a fresh intake each day. The water-soluble group is comprised of vitamin C and the B-complex vitamins: thiamine (B1), riboflavin (B2), niacin (B3), pantothenic acid (B5), pyridoxine (B6), cyanocobalamin (B12), biotin, choline, folate, inositol and Para-Amino-Benzoic Acid (PABA). Choline and biotin are unique in the B vitamins as the body can produce them in limited quantities.
Fat-soluble
(lipophilic) vitamins dissolve in fat, not water. They are stored in the body, mainly in the liver and fatty tissues, and do not necessarily require a fresh supply on a daily basis. Intake of too much of these vitamins can cause a storage-overload in the body and can be toxic. Fat-soluble vitamins include vitamins A, D, E and K.
HSR
examined five of the leading chronic health conditions—obesity, diabetes, cardiovascular disease, bone and joint health, and brain function—facing today’s consumers and explored how vitamins work in the body to prevent dysfunction and aid in many forms of disease relief.
Obesity
Obesity is a disease that affects nearly one-third of American adults, according to the American Obesity Association (AOA) (www.obesity.org); a record 64.5 percent of adult Americans (about 127 million) are categorized as being overweight. Obesity poses a major risk for such chronic diseases as Type II diabetes, cardiovascular disease, hypertension and stroke, and certain forms of cancer.
Obesity is associated with vitamin D insufficiency due to the decreased bioavailability of vitamin D3 from cutaneous and dietary sources because of its deposition in body fat components.2 In addition, micronutrient deficiencies can become problematic in overweight or obese subjects due to dieting—especially unhealthy dieting. For example, researchers from the University of Minnesota, Minneapolis, found adolescent girls using unhealthful weight-control behaviors had significantly lower intakes of fruit, vegetables, grains, vitamins A, C, B6 and folate than girls on healthful diets.3 Generally, anyone strictly adhering to a diet consisting of less than 1,500 kcal/d may benefit from a general multivitamin and mineral supplement to boost intake to meet dietary reference values.
Following gastric bypass surgery and other obesity-related surgeries, patients are only able to consume very minute amounts of food and drink and thus require lifelong medical supervision to monitor potential complications including micronutrient deficiencies.4 Particular associated vitamin deficiencies include vitamins B1 and B12.5
Since these types of surgical procedures also result in some loss of absorptive function, the long-term consequences of potential nutrient deficiencies also must be recognized and adequate monitoring must be performed, particularly with regard to vitamin B12, folate and iron.6 According to a 14-year follow-up of gastric bypass surgery complications, vitamin B12 deficiency was the number one complication reported, which occurred in 39.9 percent of cases.7
In another study examining iron, B12 and folate deficiency in 348 gastric bypass patients over a 10-year period, scientists found iron and vitamin B12 levels lower than the preoperative level.8 Oral supplementation of iron and vitamin B12 corrected deficiencies in 43 percent and 81 percent of patients, respectively. Folate deficiency was almost always corrected with multivitamins alone.
Studies also show multivitamins, especially the B vitamins, can help to slow weight gain.9 In a study conducted at the Fred Hutchinson Cancer Research Center in Seattle, researchers collected the diet and supplement routines of 330,000 men and women age 50 to 76. The individuals who gained the least weight were those who had consumed multivitamins, vitamin B6 and B12. The researchers hypothesized that individuals lacking micronutrients such as B vitamins might eat in excess, trying to correct the deficiencies, whereas those supplemented tended toward lower caloric intake diets.
Diabetes
Diabetes is a group of diseases characterized by high levels of blood glucose resulting from defects in insulin production, insulin action, or both. Diabetic conditions include Type I, Type II, gestational and pre-diabetes. At least 171 million people worldwide have diabetes, according to the World Health Organization (WHO), and that number is likely to more than double by 2030. Vitamin supplementation has been shown to work in many positive ways to aid and prevent diabetes.
In pre-diabetes (a state of elevated blood glucose levels, yet not high enough for a diagnosis of diabetes), vitamin supplementation has been shown to lower incidence of the full onset of diabetes. Development of Type II diabetes may be reduced by the intake of antioxidants in the diet as shown in one study conducted at the National Public Health Institute in Helsinki, Finland.10 A cohort study of 2,285 men and 2,019 women, aged 40 to 69 years and free of diabetes at baseline (1967 to 1972), was studied. During a 23-year follow-up, the study found vitamin E intake was significantly associated with a reduced risk of Type II diabetes, as were select single carotenoids including the vitamin A precursor beta-cryptoxanthin.
In another population-based, follow-up study conducted in eastern Finland, a strong independent association was found between low vitamin E status and an excess risk of diabetes.11
Researchers found a low lipid standardized plasma vitamin E concentration was associated with a 3.9-fold risk of incident diabetes, supporting the theory that free radical stress plays a role in development of Type II diabetes. In still another study, vitamin C supplementation was found to decrease insulin glycation by 80 percent and ameliorate aspects of the obesity-diabetes syndrome in adult lean and obese hyperglycemic mice.12
The beneficial role of vitamin C and other antioxidants in the prevention of impaired glucose tolerance is especially evident in gestational diabetes. Vitamin C has been found to be an effective combatant in reducing its occurrence as shown in a study conducted at the University of Washington, Seattle.13 Women with plasma vitamin C in the lowest quartile had a 3.1-fold increased risk of gestational diabetes compared with women whose concentrations were in the upper quartile. Women who consumed less than 70 mg/d vitamin C experienced a 1.8-fold increased risk of gestational diabetes compared with women who consumed higher amounts in the study and in another study,14 women reporting the same daily vitamin C intake (less than 70 mg/d) experienced a 3.7-fold increased risk of gestational diabetes.
Type II diabetics also may benefit from the effects of vitamin C. In a study evaluating blood sugar and antioxidative status, Type II diabetes mellitus patients (31) were given 1 g/d vitamin C.15 Following the vitamin C supplementation, plasma vitamin C concentration was significantly increased and fasting blood sugar and HbA1c was significantly decreased.
The vitamin D analog significantly down-regulates in vitro and in vivo proinflammatory chemokine production by islet cells, inhibiting T cell recruitment into the pancreatic islets.16 This novel mechanism of action exerted by the vitamin D receptor ligands was found to be potentially relevant for the treatment of Type I diabetes and other autoimmune diseases. Oral vitamin E treatment appears to be effective in normalizing retinal hemodynamic abnormalities and improving renal function in Type I diabetic patients without inducing a significant change in glycemic control, according to a study conducted at the Joslin Diabetes Center in Boston.17 Vitamin E supplementation also was found to increase glutathione concentrations by 9 percent, and lower concentrations of malondialdehyde by 23 percent and of HbA1c by 16 percent in erythrocytes in Type I diabetic patients.18 Glutathione levels were found to be significantly related to vitamin E levels, according to the study.
Cardiovascular Disease
For 2004, the estimated direct and indirect cost of cardiovascular disease (CVD) is $368.4 billion.19 Types of CVD include high blood pressure, coronary heart disease—including myocardial infarction (heart attack) and angina pectoris (chest pain)—congestive heart failure, stroke and congenital cardiovascular defects.
Antioxidants, including vitamins A, C and E, can fend-off free radicals and help prevent cell damage.20 Carefully controlled experimental studies continue to indicate vitamin A and the provitamin carotenoids are effective for mitigating and defending against many forms of CVD.21 Consumption of an antioxidant-rich diet also works to reduce the plasma levels of lipid peroxide and cardiac enzyme and increase the plasma level of vitamin C. Antioxidant-rich foods may also reduce myocardial necrosis and reperfusion injury induced by oxygen free radicals.22
In one study conducted in Madrid, researchers found an association between acute myocardial infarction and reduced blood levels of vitamin A and E, not explained by the decrement in blood lipids levels; therefore, low blood levels of fat-soluble vitamins may be a risk factor for the development of this disease.23
In another study concerning blood content of vitamins A, C and E, 22 patients with stable exercise-induced angina and 28 patients with postinfarction cardiosclerosis without circulation failure were studied.24 The study found in patients with stable exertional angina, the blood plasma content of vitamin C was higher, and patients with postinfarction cardiosclerosis showed increased levels of vitamin A in erythrocytes as well as vitamin C in blood plasma.
Vitamin E also has been shown to raise the levels of HDL (“good” cholesterol) in the body and block the oxidation of LDL (“bad” cholesterol) and can increase carotid artery compliance.25 Dietary supplements of vitamin E also can sustain better cardiac function subsequent to myocardial infarction.26
Vitamins B6, B12 and folate have been shown to reduce levels of homocysteine, an amino acid that has been linked to heart disease.27 According to scientists at the University of Bergen, Norway, vitamin B6 is necessary for the metabolism of homocysteine and is often used in combination with folic acid and vitamin B12 in clinical trials that investigate whether the lowering of plasma total homocysteine (tHcy) can prevent vascular disease. In one clinical trial, a folic acid and vitamin B12 combination provided rapid, substantial and long-term tHcy-lowering effects, whereas the effect of vitamin B6 on tHcy was found to be relatively small and confined to PML tHcy. However, vitamin B6 treatment did cause a marked reduction in plasma cystathionine.28
Bone and Joint Health
Osteoarthritis (OA) is a painful, degenerative joint disease that primarily affects cartilage, causing it to fray, wear, ulcerate, and in extreme cases, disappear entirely, leaving a bone-on-bone joint. Another common condition is osteoporosis. Osteoporosis is loss of bone density, bone tissue or mass that causes bones to become fragile and break.
Many (although not all) forms of arthritis are directly related to inflammation.29 Many vitamins can play a very helpful role in arthritis and other bone-related ailments. For example, inflammation has been shown to be related to impaired vitamin B6 status in rheumatoid arthritis (RA) patients.30 In addition, markers of vitamin B6 status were found to be associated with disease activity and severity, synovial burden, and pain in RA patients.
Important vitamins acquired simply through diet can help in the fight against symptoms and even onset of certain arthritic conditions. In one prospective, population-based, nested, case-control study of residents of Norfolk, England, men and women aged 45 to 74 were recruited between 1993 and 1997 to investigate any association between consumption of fruit and vegetables and dietary antioxidants and the risk of developing inflammatory polyarthritis (IP).31 The study found patients with IP consumed less fruit and vitamin C than matched controls, which appeared to increase their risk of developing IP. Vitamin D and calcium are the bestknown bone-building, protective supplements —usually working together for a positive outcome. Vitamin D aids in the absorption of calcium; this is why milk is fortified with vitamin D. Vitamin D supplements also can act synergistically to reduce fracture risk.32 Intake levels of calcium and vitamin D also have been shown to have a beneficial effect on osteoporosis as well as tooth retention.33
Brain Function
Thiamine deficiency (TD) has been shown to lead to memory deficits and neurological disease in animals and humans.34 Several studies show TD results from chronic alcohol consumption and is one factor underlying alcohol-induced brain damage. A reduction in thiamine can interfere with numerous cellular functions, leading to serious brain disorders including Wernicke-Korsakoff syndrome, which is found predominantly in alcoholics. Chronic alcohol consumption results in TD by causing inadequate nutritional thiamine intake, decreased absorption of thiamine from the gastrointestinal tract, and impaired thiamine utilization in the cells.35 People differ in their susceptibility to TD and different brain regions are more or less sensitive to this condition.
Niacin also plays a role in brain health. Dementia results from severe niacin insufficiency,36 but it is unknown whether variation in intake of niacin in the usual diet is linked to neurodegenerative decline. Dietary niacin also may protect against Alzheimer’s disease (AD) and age-related cognitive decline.37
Between 6 percent and 8 percent of all persons aged 65 and older have AD and the prevalence of the disease is increasing. Nutrition seems to be one of the factors that may play a protective role in AD. Many studies suggest that oxidative stress and the accumulation of free radicals are involved in the pathophysiology of the disease.38 Studies have also shown the existence of a correlation between cognitive skills and serum concentrations of folate, vitamin B12, vitamin B6, and, more recently, homocysteine.39
Antioxidant nutrients have been found to possibly help protect these affected brain regions. Data from scientists at the University of Cape Town, South Africa, supports the free radical theory of oxidative neuronal damage.40 The South African study investigated whether plasma vitamin C and E status is lower in subjects with AD and dementia. The case control study included 15 subjects with AD, 28 subjects with senile dementia and a control group of 50 subjects with no cognitive impairment.
Controls were found to have a significantly higher plasma vitamin C concentration than dementia patients. The dementia group was found more likely to have sub-optimal plasma vitamin C levels than control subjects—despite having similar dietary vitamin C intakes. Plasma vitamin C levels also were lower in subjects with dementia, compared to controls, which also was not explained by their dietary vitamin C intakes.
Adequate doses of essential vitamins can keep the mind sharper for longer. Adequacy of B vitamins—especially B6—helps with mental clarity and antioxidant vitamins C and E also can contribute to the maintenance of mental clarity.41 Deficiencies in the B vitamins and in vitamin C have been linked to depression because they are vital for the production of neurotransmitters.42
Helping Consumers Understand
Most have a general idea that vitamins are good for their health; however, not everyone knows the extent of the benefits of each individual vitamin. Retailers must help educate the consumer of the effects of insufficient or excessive amounts each individual vitamin may harbor.
“It is essential for people to know what they are taking, especially for those who have special needs,” said Lisa Liao, director of product development and marketing with City of Industry, Calif.-based K-Max Health Products (www.kmaxonline.com), “Retailers should give out plenty of information on the vitamins and supplements they sell to consumers. Some people might walk in to the store and don’t know what they need to take to get the results they want. Retailers should be able to assist consumers in finding the right products for their needs.”
Catherine Wenceslao, marketing and sales coordinator for Irvine, Calif.-based Boscogen Inc. (www.boscogen.com) agreed. “Consumers will walk into a store and just be overwhelmed with all the vitamins and nutritional supplements on the shelf,” she said. “It is best to promote the natural ways to prevent dysfunctions and how they are better than trying to prevent them other ways, but the main idea here is education on the product, what does it do, why take it, who should take it, etc. Retailers should make this information easily accessible to the consumer.”
In addition, retailers also must guide their customers to the correct form of vitamins best suited to fit each need. Is a multivitamin more effective or should this particular consumer take a singular formula?
“Multivitamins give you all the essential and non-essential nutrients you need in one product,” Liao said. “It will help to enhance overall health for your body. As for a single vitamin, it will be able to focus on a certain benefit such as bone and teeth strengthening, wound healing or treatments of cold and flu symptoms.”
Nov. HSR Vitamins References:
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