The past two weeks have seen a number of conflicting research articles published on the relationship between folic acid and cancer. Folic acid is a B-vitamin that is essential for the biosynthesis, metabolism and repair of DNA, and metabolism of amino acids. Adequate intakes of folic acid are needed in the same biochemical pathways along with other B vitamins such as vitamin B12, vitamin B6 and riboflavin. Inadequate folic acid intakes may affect cancer risk because DNA synthesis or repair is hindered, or levels of inflammatory amino acid homocysteine are elevated. The introduction of folic acid fortification in many countries over the last 15 years has improved folic acid status of entire populations.
Archive for 'October 2012'
The 'French Paradox' is based on the observation that cardiovascular risks in countries with high intakes of saturated fat are lower where people consume wine. The question has been: is the benefit derived from alcohol or a component found in wine? Resveratrol is an antioxidant found in grapes and wine, especially reds, which helps prevent oxidative damage from free radicals. The daily consumption of 250 mL of red wine for 3 weeks has been shown to improve endothelial function, often referred to as flow-mediated dilation (FMD). At the 24 th scientific meeting of the International Society of Hypertension this fall, Wong and colleagues reported (Abstract 231) that 75mg of resveratrol daily for 6 weeks resulted in a 23 percent increase in FMD in obese men with mild hypertension. Previously, acute doses of resveratrol had been reported to improve FMD in overweight individuals with mild hypertension.
Iron deficiency anemia has been identified as an area of concern by many international organizations concerned with improving health of nutritionally impoverished populations, particularly to improve concentration, learning and work capacity. Omega-3 fatty acids have been identified as important for cognition and heart health. Results from a randomized 2x2 factorial placebo-controlled trial in South African school children were published in the American Journal of Clinical Nutrition by Baumgartner and colleagues. The trial randomized 321 children with poor iron status aged 6 to 11 to either 50 mg iron or a DHA/EPA supplement with 420mg DHA and 80 mg EPA four days per week. The iron dose was very high and designed to reduce deficiency
Vitamin D is currently the most actively researched vitamin. Every week, TalkingNutrition finds scientific articles published about vitamin D: its role in many aspects of human health, bioavailability, consumption and risk groups. In the last two days, two articles were published about the relationship between circulating levels of vitamin D and adequacy. The first publication (Kramer et al) looked at circulating levels of people with reduced kidney function compared to the general population. The second (Taylor et al) used a new approach to determine population levels of vitamin D adequacy.
If you are anticipating the 8pm ET opening pitch for the 2012 World Series Fall Classic, did you know that the outcome might depend upon whether these veterans eat their vegetables? As Hammond Jr and Fletcher write, baseball players tend to have very good visual acuity. College baseball players have ~15% better dynamic visual acuity than their peers. Lutein and zeaxanthin are carotenoids found in vegetables – spinach, kale, turnip greens, collards, dandelion greens, etc. They are the only carotenoids found in the eye, out of ~200 carotenoids found in the diet. Lutein and zeaxanthin are concentrated in the macula of the eye at levels 10,000 times that found in blood.
Low maternal vitamin D levels during pregnancy may increase child’s risk of having eczema. Jones and colleagues measured cord blood serum 25(OH)D concentrations in 231 Australian infants and the subsequent development of infant eczema and allergies. They found: Lower cord blood serum 25(OH)D levels were correlated with risk of child eczema Maternal supplemental vitamin D use increased cord blood vitamin D levels Eczema was most prevalent in those with serum 25(OH)D levels <50 nmol/L
Healthy children are the desire of every parent. And grandparent. And godparent. And the list goes on. Yesterday’s blog ‘Vitamin D, Pregnancy, and the First 24 Months of Life’ discussed the importance of vitamin D during the first 1,000 days. Today we learn that women who take a folic acid supplement before and during pregnancy may reduce the risk of their child developing a brain tumor by almost 50%. Using data collected from 327 children with cancer at 10 pediatric oncology centers in Australia, and 867 control children, Milne and colleagues report that using a folic acid supplement before and during pregnancy may protect children from brain tumors.
Tuesday was World Food Day, sponsored by the Food and Agriculture Organization of the United Nations, to increase awareness about the importance of improving food security and ending hidden hunger. A study published in the British Journal of Nutrition emphasizes the importance of micronutrients for children. Each year 2.8 million children under 5 years die from malnutrition. As the infographic in the Sight and Life Magazine shows, this can be stopped for only pennies a day by Scaling up Nutrition. Recognizing that nutrition interventions in Vietnam do not target school children despite a high prevalence of micronutrient deficiencies, Hieu and colleagues conducted a randomized, placebo-controlled study with 403 children (6-9y).
Today’s blog is an exclusive article written for Everything Nutrition in Nutraceuticals World. Ok, I admit, this piece was stimulated by a news article not a peer-reviewed paper. My ire was raised when I read the Australian Herald Sun headline - "Experts fear popping vitamins may corrupt kid's dietary habits into adulthood". Here are some direct quotes: Sales of children's vitamin pills soared 20 per cent in the past year to $10 million, a new study reveals. And the sales leap comes at a time when government research shows only one fifth of children aged 4-8 is eating the recommended daily serves of vegetables. Nutritionists fear the surge in kiddie vitamins is sending the wrong message about healthy eating habits.
A new study reports that using multivitamins may help reduce the risk of cancer in men. Gaziano and colleagues examined data from the Physicians’ Health Study (PHS) II, a large-scale, randomized, double-blind, placebo-controlled clinical trial (RCT) of long-term multivitamin use in 14,641 middle-aged and older US medical doctors. They report an 8% reduction in total cancer risk in men taking a multivitamin daily (vs placebo). As stated by the Council for Responsible Nutrition vice president of scientific and regulatory affairs Duffy MacKay ND, “the study reinforces the value of long-term consistent use of a daily multivitamin as a convenient and affordable insurance policy for health.”
On October 16 every year, World Food Day is celebrated, a day that highlights the challenges feeding a growing population. This event is organized each year by the Food and Agriculture Organization of the United Nations and many groups and organizations to raise awareness about the issues surrounding malnutrition, poverty and hunger. The statistics on hunger are staggering: around 870 million people are food insecure, according to the FAO in their most recent report (listen to the podcast with World Food Program Chief Economist, too). The causes of under-nutrition are complex and interrelated. Weak political situations, social instability, and poor economic growth all contribute to catastrophic situations in which populations cannot cope with normal fluctuations in local food production. The FAO has identified key areas that require focus to continue progress in reducing global hunger.
The news today on the Women’s Antioxidant and Folic Acid Cardiovascular Study reminded me of a paper entitled ‘A potential design flaw of randomized trials of vitamin supplements’ published April 11, 2011 in JAMA. Morris and Tangney wrote: “Vitamin treatment may not be effective in these trials because nutrient intake among the participants is already at optimum levels. To specify, examples are provided from the field of dementia and investigations of 3 dietary components: vitamin E, B vitamins, and docosahexaenoic acid.” Song and co-authors didn’t find statistically significant effects of combined folic acid, vitamin B6, and vitamin B12 treatment on colorectal cancer risk among women at high risk of cardiovascular disease. However, these women were consuming
Imagine, a week almost past without a blog posting on vitamin D. This is a rarity given the number of scientists who have turned their attention to vitamin D. Well, it didn't happen. Vitamin D is in the news again this week. Today's blog focuses on a new report linking vitamin D status with virologic responses to therapy in patients co-infected with human immunodeficiency virus (HIV) and hepatitis C virus (HCV). Mandorfer and colleagues retrospectively examined samples from 65 patients who received chonic hepatitis therapy (PEGIFN+RBV). They report more patients (n=37, 57%) with deficient serum 25(OH)D levels (<25 nmol/L) than inadequate (26-75 nmol (n=15; 23%) or normal levels (n = 13, 20%). The authors highlight statistical differences in immunological variables and
Carotenoids are brightly colored pigments that give tomatoes their red color, make carrots orange and corn yellow. Carotenoids are important for health, and the most well-known example is that some carotenoids are converted to vitamin A, making them an important source in diets around the world. The discovery of the antioxidant qualities of carotenoids has also encouraged research into other areas of health, and the current focus is on immunity, vision, skin, and cognition. The science is evolving quickly, so it is useful that the American Journal of Clinical Nutrition has just published online a selection of articles based on presentations at the recent "New Developments in Carotenoid Research" symposium held in Boston in March, 2011. These articles provide an overview of cutting edge topics in carotenoid research.
Keeping up with the latest science on omega-3 fatty acids isn’t easy. There are so many topics of interest. Omega-3 intake and cardiovascular health. DHA and brain development in kids. DHA and vision. A new study reports omega-3 fatty acid supplementation may also help with symptoms of depression. Rizzo and colleagues recruited 76 female residents (65-95y) living in a nursing home. They were randomized to receive placebo or omega-3 fatty acids (~0.83 g DHA and 1.66 g EPA) daily for 8 weeks. All participants were required to have a Mini-Mental State Examination (MMSE) score > 24. Baseline Geriatric Depression Scores (GDS) were 17. The levels of EPA and DHA in blood were lower in depressed subjects. Omega-3 supplementation significantly increased
Because of their 120d lifespan and the fact that only developing erythrocytes take up folate, red blood cell (RBC) folate concentrations are indicative of longterm folate status. The cutoff for RBC folate depletion is 305 nmol/L (140 ng/mL) and folate insuffiency to prevent neural tube defects (NTD) is 906 nmol/L (400 ng/mL). These levels are based on an Irish case-control study showing an 8-fold increased risk of NTD in women < 340 nmol/L and 2-fold increased risk in women with RBC folate concentrations measuring 680-906 nmol/L versus those >906 nmol/L. A new EJCN publication reports that 39% of Belgium women have a less than optimal folate status to prevent NTD. Belgium is a country without folate food fortification or periconceptual folic acid supplementation policies. Fortification policies beginning in the late 1990s have significantly increased folate intakes and serum folate concentrations in the US and Canada.
Almost 26 million children and adults in the US have diabetes. Diabetes is almost twice as prevalent (12.6%) among non-Hispanic blacks as non-Hispanic whites (7.1%). Adults with diabetes have 2-4 times higher heart disease death rates than adults without diabetes. Mild to moderate vitamin D inadequacy has been proposed as a risk factor for diabetes. Using data from the Danish Monitoring Trends and Determinants of Cardiovascular Disease (MONICA) collected from 2,656 persons during 1993-1994 and followed for 10 years, Husemoen and colleagues examined the relation between serum vitamin D levels and incident diabetes. At baseline, the average serum 25(OH)D levels were 60-62 nmol/L (ranging from mid-forties to low-eighties). Low serum 25(OH)D levels were significantly associated with diabetes risk in people.
The prevalence of type 2 diabetes has been rising in recent years as the obesity epidemic has evolved. The effect of excessive caloric consumption on adiposity and the risk of type 2 diabetes is well known. Micronutrients may also modulate risk as they are bioactive molecules that contribute to epigenetics and may act on pathways associated with diabetes or its pathology. Vitamin K1, otherwise known as phylloquinone, has been the subject of research by Ibarrola-Jolado and co-workers. These investigators are involved with the PERIMED randomized controlled trial of dietary interventions associated with the Mediterranean diet in multiple centers located in Spain. They used cross-sectional and longitudinal dietary assessment data to determine the association between vitamin K1 intakes and the development of type 2 diabetes.
Resveratrol has been linked with cardiovascular health since the "French Paradox" theory was first proposed to explain the low rates of cardiovascular disease despite high saturated fat intakes in the French population. Researchers have been looking for the dietary factor responsible for maintaining heart health in the French. One feature of the French diet is the liberal consumption of red wine. Resveratrol is a bioactive component in red wine that shows potential for being the mystery compound responsible for keeping the heart and blood vessels healthy. At the International Society of Hypertension's 24th annual meeting held in Sydney Australia, a research team from the University of South Australia presented results from a randomized placebo-controlled clinical trial that tested the effects of resveratrol on circulatory function in obese subjects.
Wouldn’t it be wonderful if nutrients could prevent colds and flus? Then nobody would ever get sick and there wouldn’t be any need for medications or vaccinations. Life would be grand. Life is, however, fraught with challenges. So, it is not surprising that Murdoch and colleagues did not find that vitamin D supplementation, once a month, did not reduce the incidence or severity of upper respiratory tract infections in 322 healthy individuals. It is especially not surprising given the trial was conducted in individuals with above average vitamin D status. Their average serum 25(OH)D levels were 72.5 nmol/L, well above that observed in many populations.
Asthma is a common problem found in around 9% of children in developed countries (the CDC reports that 9.4% of US children have asthma), and may persist until adulthood. Asthma is a condition that is characterized by inflammation in the airways that can restrict airflow and cause breathing difficulties. Antioxidants have been shown to have anti-inflammatory properties, therefore there is research interest in whether antioxidants in the diet can affect asthma. Nakamura and co-workers report today in the journal Public Health Nutrition about the association between asthma and the antioxidant vitamins C and E.
There is still time to register and attend the Council for Responsible Nutrition (CRN) Workshop and Annual Conference in Laguna Beach, CA this week. CRN founded in 1973 is based in Washington, D.C. It is the leading trade association representing dietary supplement manufacturers and ingredient suppliers. Its member companies manufacture popular national brands and store brands marketed by major supermarkets, drug store and discount chains. These products include those marketed through natural food stores