Following on from our recent post about the most researched vitamins of 2011, we move onto the most influential articles of 2011 in vitamin research. For this exercise, we used the search engine Scopus to search for all articles containing the word “vitamin” published this year, and sorted according to the number of citations this year. Since articles published earlier in the year have an advantage in terms of the amount of time available for it to be cited, the number of citations was divided by the number of months to give a better indication of how influential the article was.
Archive for '2011'
We are nearing the end of the year, and it is always a good time to look back and reflect on the previous 12 months. We monitor nutrition science every day and we have a feeling for which areas of research are booming, and which ones are less interesting. Still, all vitamins are being actively researched and the question is: which one is the most popular?
Remember, this is the holiday season. Maybe you can remember what you ate over the past few days, but are you willing to record how much? Did activities shorten your usual exercise routine? Keep your answers in mind because the two new studies in Journal of Nutrition rely upon food recall data to construct diet-nutrient-relationships. Unfortunately, in the absence of validated biomarkers, cost, and sometimes convenience, measures of diet quality and food intake are often the only data available to investigate the relationship between nutrition and health. McNaughton and colleagues used 4 day weighed food record data obtained by trained interviewers from people 65 years and older living in mainland Britain.
Muscle diseases like muscular dystrophy may reflect a failure of muscle to repair. Muscles may also be damaged when working. Vitamin E helps maintain cell membranes – muscle, immune, neuronal cells, and others. Howard and colleagues tested the hypothesis that vitamin E, acting as a membrane associated antioxidant, would promote repair of skeletal muscles in vitro. The results of these tests strongly confirm the essential role of vitamin E. According to senior co-author Dr Paul McNeil,
Warning: Read the last paragraph first. Deficiencies in B vitamins are known to elevate blood homocysteine concentrations. Supplementation with folic acid, B6 and B12 reduces homocysteine concentrations. Elevated homocysteine levels have been linked with cardiovascular disease. Therefore, B vitamin supplementation must reduce risk of death from cardiovascular disease. Paradoxically, randomized controlled trials (RCT) with B vitamin supplementation in individuals who previously have had a heart attack, eg SEARCH trial, reduced homocysteine concentrations but not primary outcomes attributable to vascular (coronary death, second heart attack, or stroke) or non-vascular (cancer) causes. In a JAMA article by Spence and Stampfer, they suggest
Within Canada and the US, the Institute of Medicine convenes a panel of experts to review the literature and set recommendations for each nutrient. These recommendations are set for the general, healthy population. That is logical. It seems appropriate. But what if you have a disease, a common disease, and your medication puts you at risk of a nutrient deficiency? A study published in Diabetes Care Journal reports that metformin, a medication prescribed for people with diabetes mellitus, may double the number of people who are vitamin B12 deficient. Unless you take a vitamin B12 dietary supplement. Use of supplements containing vitamin B12 was associated with a reduction in the prevalence of vitamin B12 deficiency.
Would you predict the number of miles your car could be driven based on the amount of money the last driver, perhaps a teenaged offspring, said they spent on buying gasoline? Not likely. It’s not the amount of gasoline purchased, it is the quantity of gas in the tank that matters. A better estimate to accurately predict the distance a car can be driven before the tank is empty is the gas gauge. So, what justifies scientists making health projections based on self-reported vitamin D supplement usage rather than serum 25(OH)D concentrations? Two recent studies compared the effect of vitamin D supplement usage vs placebo on health outcomes. Using supplement usage as a health predictor is equivalent to using gasoline receipts, rather than a vehicle’s gas gauge, to predict ‘miles-to-go’ before it runs out of gas.
Everyone knows about vitamin C and its role in supporting a healthy immune system. Nobel Laureate Linus Pauling took 3 grams of vitamin C daily to prevent colds. He encouraged people to consume vitamin C above and beyond the RDA of 75 and 90 mg daily for men and women 19y and older, respectively. Awareness of the link between citrus fruit and vitamin C became universal when sailors were nicknamed ‘limeys’ because ships were stocked with limes to prevent scurvy during long oceanic crossings. So it is shocking to read that ¾ of elderly people in Northern India and 46% in Southern India are vitamin C deficient
As a science communicator, do headlines drive you crazy? Where are readers to get perspective on individual studies? The benefits of vitamin D are getting undermined by headlines. TheHeartOrg publishes “Vitamin D fails again to affect CV mortality”. Reuters publishes “Vitamin D doesn’t prevent heart attack or cancer” with the lead sentence reading “Among seniors with a high risk of bone fractures, taking vitamin D or calcium pills has no impact on their chances of dying from cancer or vascular disease”. These headlines miss the point. Results from the RECORD trial are suspect for several reasons:
With end-of-year celebrations, it is easy to overconsume. Waistlines expand. Clothes tighten. And associated with these changes comes increased risk of non-communicable diseases – obesity, diabetes, cardiovascular disease, and others. Is there anything that we could feel good about eating? Or are the next few weeks only a time of resisting temptations? Two new studies in the American Journal of Clinical Nutrition provide hope. Research suggests that vitamin D and calcium may play a role
Vitamin B12 is a water-soluble vitamin that has several essential roles. It is needed for the formation of red blood cells, nerve sheaths and proteins. It also participates as a coenzyme in metabolic reactions, particularly recycling homocysteine to methionine. For this reason, elevated homocysteine levels, a risk factor for cardiovascular disease, can also indicate vitamin B12 deficiency. Vitamin B12 is only found in animal products putting vegetarians at risk of deficiency. Researchers are concerned that low vitamin B12 levels can place vegetarians at risk of cardiovascular disease.
More than 1.5 million American adults treat attention deficit hyperactivity disorder (ADHD) with medications. In a JAMA article published yesterday, Habel and colleagues examine the effect of these medications on risk of cardiovascular events in these young and middle-aged adults. They did not find any increased CVD risk with medication use. In an accompanying editorial, Philip Shaw MD PhD writes that “the findings support the final decision by the US FDA in 2006 not to place a black box warning of serious cardiovascular events on ADHD medications for all children and adults.” This is good news but wouldn’t it be better to remove environmental factors contributing to ADHD? The effect of azo dyes in foods and beverages on ADHD incidence is unresolved. The FDA’s Food Advisory Committee met
Acronyms are used by everyone. They are part of our culture – DSM, BMW, CEO, ATM – and we haven’t even got to nutrition. Consider healthy fats. Do you have an adequate intake of omega-3 fatty acids? Is the omega-6:omega-3 ratio of your diet healthy? Are you getting enough DHA and EPA? Interpreting this alphabet soup of acronyms may be as elusive as membership in a fraternity, say ΦβΚ. The list of acronyms is a stew of letters. A stew that may even contain the kitchen-sink. A refreshing distillation of these acronyms was written by Emily Izer, a University of Maryland dietetic intern who wrote a blog for Food Insight. She nicely explains
Is half your plate filled with fruit and vegetables? If you are an adult, are you eating 2-3 cups of vegetables and 1-2 cups of fruit daily? Probably not. And you should be. Most phytonutrients are found in fruits and vegetables. Despite dietary recommendations to increase the consumption of fruits and vegetables for decades, consumption remains low. Indeed, a single food accounts for 64% or more of the total intake of phytonutrient for 5 (α-carotene, β-cryptoxanthin, lycopene, hesperetin, and ellagic acid) of 9 phytonutrients. Antioxidant-rich diets inhibit oxidative stress and inflammation, reducing the risk of stroke.
Complementary food supplements (CFS) are a useful form of micronutrient fortification of meals. CFS is supplied as a liquid, powder or crushable tablet that is added to food directly before it is eaten to increase its nutritional content, and is also referred to as home fortification. There are many practical advantages to CFS above community- or population-level food fortification, or direct supplementation. A recent study in the European Journal of Clinical nutrition by Samadpour et al. compares three methods of CFS in a trial in a high-risk population in Iran. The authors report that around one third of children in Iran are affected by iron and zinc deficiencies. Vitamin A and D deficiencies are also common in some regions. The government provides multivitamin drops for children aged under two years. Nutritional supplementation in the 1000 days window of opportunity may have a lasting impact on long-term health and development.
Having a baby? If so, remember that folic acid is essential for neural development in infants, especially during the first trimester of pregnancy. And actually, research shows it is important during the first years of life as well. Researchers from Norway reported that folic acid supplementation in early pregnancy reduces the risk of severe language delay in children at 3 years of age.
Modern-day painter, Alev Oguz, is to have said, “The soul never ages. My soul dances without my feet. I am the music.” Unfortunately, eyes do age. According to the 2010 Gallup Study of the market for vitamins & other dietary supplements, eye health ranks in the top 5 health concerns of adults 65 years and older. In their Practice Strategies review in Optometry, Journal of the American Optometric Practice, Elliott and Sumner Williams write that 81% of adults experience eye discomfort caused by glare or fatigue while driving at night, 41% while being outside during the day, 39% while driving or riding in a car during the day, and 26% while being at the beach or boating, and 25% while working on a computer. That is most adults in typical activities.
Remember being told to eat your vegetables? Or being told to finish your milk? Or being redirected to have a piece of fruit as a snack after coming home from school? Well, new research confirms this sage advice. Rautiainen and colleagues examined food frequency questionnaires (FFQ) from women, 49-83 years, participating in the Swedish Mammography Cohort. They estimated total antioxidant capacity (TAC) of the diet using a standard database for these foods. Not surprisingly, fruits and vegetables were the best sources of antioxidants, followed by whole grains. Fruit and vegetables are great sources of antioxidants such as vitamin C and carotenoids: beta-carotene, lycopene, lutein and zeaxanthin.
Puzzles test knowledge, skill or thinking. Creativity can lead to ‘eureka’ moments but scientific advances typically require rigorous examination and effort. Scientists ‘puzzle’ by testing hypotheses – using existing evidence, without assumption of truth, and proposing explanations as a starting point for further investigation. Micronutrient deficiency is a public health puzzle for many countries. People suffer from deficiency diseases associated with vitamin D (rickets), iron (anemia), vitamin C (scurvy), vitamin A (blindness), etc. The ‘Live ad Let Die’ refers to nutrient intakes where deficiency diseases are absent but quality of life may be compromised.
Answers to nutrition-related questions are never simple. Answers tend to be like the old conundrum: which came first, the chicken or the egg? Today’s blog asks, how many self-reported food frequency questionnaires (FFQ) or dietary records are needed to accurately estimate food (and nutrient) intake over a year or decade? Is it 1? Is it 2? Is it more than 1 per year? Do correlated factors (diet, physical activity, smoking, alcohol consumption, education level, socioeconomic status) make it impossible to discern the effect of nutrients on non-communicable disease (NCD) patterns? Maybe the answer depends upon which came first. Human behavior or nutrient intake?
Wouldn’t it be great to know your vitamin status? To have answers to the questions: Am I eating properly? Do I need a dietary supplement or not? Nutrition assessment shouldn’t be a ‘food recall’ test or toss of the dice. Nutrition indicators are needed. Some are available. Vitamin D status can be measured by serum 25(OH)D status. The World Health Organization has established biochemical indicators to assess iron status (serum ferritin) and vitamin A deficiency (serum retinol). According to their website, priority nutrients are iodine, zinc, folate, vitamin C, and thiamin.
Vitamin D is required for a healthy immune system. An immune system which sometimes goes awry, destroys insulin-producing beta-cells in the pancreas, and contributes to type 1 diabetes mellitus. Researchers are now finding links between vitamin D status and the incidence of type 1 diabetes mellitus in children. Sorensen and colleagues studied a cohort of 29,072 women in Norway. They found a twofold higher risk of type 1 diabetes in children born from women in the lower quartile of serum 25(OH)D levels. Because 40-80% of pregnant women may be vitamin D deficient, it is not surprising that
The 2010 Dietary Guidelines recommend replacing meat and poultry with seafood. The American Heart Association recommends eating fish, particularly fatty fish like salmon, mackerel, sardines, herring, and lake trout, at least two times (two serving) a week. The reason: to increase intake of omega-3 fatty acids. Then there is the ‘yuck factor’ of eating fish. Taste. Smell. And the fact that fish can contain high levels of mecury, PCBs, dioxins and other environmental contaminants. Both the FDA and EPA have issued cautionary guidance to women who might be pregnant, are pregnant, or nursing and young children to avoid some types of fish. It is confusing. Eat more fish but be careful. Greenpeace International warns that many marine ecologists think the biggest single threat to marine ecosystems today is overfishing.
Only one more month in the Northern Hemisphere to go before the solstice and the days finally start to get longer. In the meantime, sufficient exposure of skin to sunlight to synthesize vitamin D will be low to non-existent. Unless you travel to a warm, exotic venue where you can spend time soaking up the sun. Otherwise, it is important to consume vitamin D fortified foods, the availability of which are limited by law in many countries, or use dietary supplements. Three studies presented at the American Heart Association annual meeting in Orlando, FL reported on the benefits of maintaining adequate serum 25(OH)D levels:
Want to eat healthier? It is best achieved by using the Nutrition Facts panel to compare foods: whether buying groceries, reading a menu in a restaurant, or perusing for snacks in the pantry or fridge. Only by comparing number of calories, grams of fat and sugar, or Daily Values (DV) for essential nutrients between foods can one make an informed, more nutritious choice. DVs help make life simpler because we don’t have to do as much math, know actual recommended nutrient values, or remember units (mmol/gram). Someone else does the calculation and labels the DV for us. How was it done?
Understanding differences between men and women in their relationships was the basis of the best selling book entitled, “Men are from Mar, Women are from Venus”. In his book, Dr John Gray provides insights into sex-based differences in brain and body chemistry which impact relationships, romance, and health. New research suggests that there are sex-specific differences in metabolism of long-chain polyunsaturated fatty acids (PUFA. Decsi and Kennedy report that sex hormone differences between men and women may lead to differences in PUFA metabolism. According to stable isotope studies, women are better able to desaturate and elongate α-linolenic acid (ALA) via eicosapentaenoic acid (EPA) to docosahexaenoic acid (DHA) then men.
With dark wet roads, nighttime driving becomes more difficult. Headlights glare, waterdrops reflect, and it is challenging to see. Two new reports suggest that following mother’s advice “eat your vegetables” plays an important role in eye health and vision. In the Practice Strategies section of Optometry – Journal of the American Optometric Association, Elliott and Williams summarize the importance of lutein and zeaxanthin in maintaining visual performance. They note that 81% of adults experience eye discomfort from glare or fatigue while driving at night. Thirty-nine percent have the same complaint while driving or riding in the car during day. Lutein and zeaxanthin are carotenoids found in vegetables
It’s a slow day for release of new nutrition research on vitamins and carotenoids. Unfortunately, The Telegraph, MSNBC, and Fox News are reporting that high vitamin D levels to a serious heart condition – atrial fibrillation. It is unfortunate because the data is suspect. As mentioned yesterday in TalkingNutrition.dsm.com, the blood vitamin D levels presented at the American Heart Association meeting need verification. There must be an error. Levels of 40-100 ng/dL (or 40-100 ng/100 mL) don’t make sense. Assuming the Utah scientists got their units wrong and not the laboratory clinical analysis, it is possible they meant ng/mL when reporting ng/dL (or ng/100 mL). If so, how many people between 30 and 70 years of age might have vitamin D levels exceeding this amount?
Earlier today The Telegraph published a headline High dose vitamin D pills ‘can double heart condition risk’. Don’t believe the headline because the results cannot be trusted. Oral presentations at scientific meetings should not be communicated to the public until the research is subjected to peer review. The data presented at the American Heart Association meeting needs to be dismissed until the scientists check their serum 25(OH)D values for analytical or mathematical errors. Dr T Jared Bunch, a heart rhythm specialist, was quoted that patients, mostly over 70y of age, having vitamin D levels above 100 nanograms per 100mL were 2.5 times more likely to have atrial fibrillation (AF) than those with normal levels (41-80 ng/100mL). So what’s wrong with this statement? It’s the vitamin D values. These cannot be correct.
Doing something meaningful is an aspirational thought. It leads to the question, “what is meaningful action?” Some movements, such as Occupy Wall Street, try to change the world through nonviolent demonstration. It can also be improving lives of women, men, and their children by advocating for better nutrition and long-term nutrition security. Nutrition adequacy and security are worldwide problems. Even in developed nations. Even amongst the overweight and obese. Snacking is often considered to contribute to obesity more than nutrient intake. Zizza and Xu set out to test this concept. They examined 24h dietary recall data from the National Health and Nutrition Examination Survey (NHANES) on 11,209 adults. Snacking was associated with a more nutrient-dense diet, partially through increased intake of fruit and whole grains
With 350 million people having diabetes worldwide and today being World Diabetes Day, it is time to talk about diabetes. Indeed, the numbers are higher because another 175 million do not know they have diabetes, that is 50% more have not been diagnosed. Diabetes leads to blindness, kidney malfunction, increased risk of a heart attack and amputation. It is deadly. Diabetes can be managed. However, it is costly. Medical expenditures among people are 2.3 times higher for those with diagnosed diabetes than those without diabetes. More than 80% of the diabetes deaths occur in low and middle-income countries. The World Health Organization projects diabetes deaths will double by 2030. What is the answer?
Proving nutrient-disease relationships is complex. Reducing the issue to placebo-controlled clinical studies with isolated compounds helps to determine nutrient bioavailability, metabolic pathways, and requirements but diseases develop over time. Because diseases are chronic and multifactorial, it is very difficult to elucidate nutrient-disease relationships. Yet, 2 studies published this week in the American Journal of Clinical Nutrition, demonstrate the importance of adequate intakes of pro-vitamin A carotenoids and vitamin A in maintaining health.
‘Bouncing off the walls’ is an expression sometimes applied to kids. Could hyperactivity be related to food colors or is their behavior due to overstimulation, excitement, pent-up energy, or maybe a behavioral disorder? For over 30 years, researchers have suggested artificial food colors might contribute to hyperactivity and learning disorders. Is this the case? The leading non-profit organization serving individuals with Attention-Deficit/Hyperactivity Disorder (CHADD) is holding their annual meeting, starting today, in Orlando, FL. This is an excellent forum to learn more about Attention Deficit Hyperactivity Disorder (ADHD).
Andrew Lang, a Scots poet, is remembered for saying, “He uses statistics as a drunken man uses lamp-posts – for support rather than illumination”. When it comes to epidemiological research relating food and supplement use with health outcomes, too often studies are cited as evidence to support a point of view rather than a basis for hypothesis generation. Au contraire and the tendency is to dismiss the study. Take for example a recent Japanese study by Hara and colleagues. They surveyed over 28,000 men and 33,000 women about vitamin supplement use and analyzed medical diagnoses of cancer and cardiovascular
Eating too much and too quickly increases risk of becoming overweight. Maps published in Archives of Pediatric & Adolescent Medicine show that too many Americans are overweight or obese. Being overweight increases cellular stress and leads to inflammation. However, having a healthy weight doesn’t guarantee good health. Every meal changes concentrations of nutrients and their metabolites in blood. Each meal-related rise in blood lipids, and the longer they remain elevated, increases inflammatory mediators of cardiovascular and metabolic diseases. Lifestyle choices such as the composition of the meals we eat, and the amount we eat at every meal/snack, affects disease risk. Just like body weight does over time. Peairs and colleagues examined the effect of meals containing 3 different high fat milkshakes
Monday mornings can be difficult to face, especially when the news isn’t good. And last week was definitely not a good week. Well, one could argue that the bathroom scales indicate it was an especially GOOD week, but weight gain was definitely not a goal. A new study published in the Journal of the American Dietetic Association provides insights to help. Simple really. Meal planning and using shopping lists. Glanz and colleagues tested the impact of a nutrient profiling tool and education surrounding food shopping and meal planning
Deficiency diseases led to the discovery of vitamins – vitamin C cured scurvy in sailors, vitamin A prevented blindness, thiamin prevented beriberi, etc – guiding the introduction of nutrient recommendations in the 1990s. Historically, nutrition scientists adopted reductionist approaches, isolating single chemical moities, testing dosages and estimating toxicities using drug paradigms involving randomized-control trials (RCTs) to develop Dietary Reference Intakes (DRIs), Dietary Reference Values (DRVs) and tolerable upper intake levels (ULs are the levels below which no adverse effects are noted). But nutrients are not drugs. While we do not all follow nutrition recommendations,
Living in the Northern hemisphere? With days getting shorter and temperatures getting colder, vitamin D status is getting worse. It is a fact. Skin can synthesize vitamin D when exposed to sunlight but most people do not spend enough time in the sun. While some foods are fortified with vitamin D, it is still difficult to obtain recommended intakes from our diets. This also applies to people living in sunny, warm climates. Orthopedic surgeons from Washington University reported that 25% of their patients (total n = 313) coming for spinal fusion operations were extremely vitamin D deficient at the 26th Annual North American Spine Society 26th Annual
With the most people needing to lose a few pounds, wouldn’t it be great to know if some food ingredient or dietary supplement could help. A study published in Cell Metabolism raises some interesting possibilities. Timmers and colleagues conducted a randomized, double-blind study where 11 obese, healthy men were treated with placebo or 150 mg resveratrol daily for 30 days. Resveratrol significantly reduced sleeping and resting metabolic rate. In essence, this preliminary study showed that resveratrol mimicked the effects of calorie restriction.
Have you ever heard or read that using dietary supplements is like flushing money down the toilet? Or that it may even increase risk of cancer? Sensational headlines and polarizing opinions may drive readership but science is based on the totality of the evidence. A Nutrition Journal paper published yesterday emphasizes the importance of an adequate micronutrient status. Mehta and colleagues studied 8 weeks of multivitamin supplementation in Tanzanian children with tuberculosis. Within 8 weeks, children receiving supplementation raised hemoglobin levels and stimulated growth (height) although weight gain did not differ.
A publication released yesterday, written by Aronson and associates and published in the journal Cancer Prevention Research, reports on a clinical study that supplemented men undergoing prostate cancer surgery with high levels of omega-3 polyunsaturated fatty acids (PUFAs) eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). The omega-3 PUFAs have a number of important roles in the body, and one of these is the regulation of inflammation.
A publication today in Neurology by Stein, Lui, Gray and coworkers reports the results of a randomized controlled trial that looked at the effects of supplying vitamin D to a group of adults with multiple sclerosis (MS). Multiple sclerosis is an autoimmune disease affecting the brain and spinal cord. It is characterized by episodes of debilitating neurological symptoms such as loss of balance, muscle spasms, vision loss, and slurred speech. It is normally considered a chronic condition, as episodes recur over decades. A review by Rosati places the prevalence between a few cases to around 150 cases per 100,000, with prevalence increasing as one moves away from the equator. This North-South gradient has suggested that vitamin D deficiency through lack of sunlight as a possible cause of MS.
Today Food Day is being celebrated across the USA. This comes one week after World Food Day, organized by the Food and Agriculture Organization of the United Nations, which focused on how stabilizing food prices is a tool to improve the food security of the most needy people in the world. Food Day has similar aims: promoting safe and healthy food, supporting sustainability, alleviating hunger, and supporting labor conditions for agricultural workers. In the US, food insecurity rates are a cause for concern, with 50 million food-insecure people, of which 17 million are children. Food insecurity is defined by the USDA as reducing quality, variety or desirability of the diet, or reducing amount of food eaten, due to difficulties obtaining food, in the past year.
Nutrition scientists, public health nutritionists, health professionals discuss personalizing nutrition – that is giving advice specific to an individual. With something like body weight (adiposity), it is easy. 1. Step on a scale. 2. Read the number. 3. Choose to ignore the number or take action to change it. 4. Decision personalized. Other health issues aren’t so easy. For measurements like blood pressure or blood glucose, people can monitor their status with a relatively minor investment in equipment. But it is much more difficult to get personal data for others such as serum cholesterol or micronutrient status. To monitor one’s health requires medical appointments, trips to laboratories, and the potential for frustrating interactions with insurance companies. Not simple or convenient. So what is personal nutrition?
Today is World Osteoporosis Day, brought to us by the International Osteoporosis Foundation (IOF). The facts are: 1. One in 3 women and one in 5 men will suffer a fracture caused by weak bones. 2. Fractures decrease quality of life because of pain and debilitation. 3. 33% of older adults who suffer a hip fracture become physically impaired and lose their ability to live independently one year after the fracture. 4. Take steps now. Embrace an active lifestyle, eat calcium-rich foods, and be certain to get enough vitamin D. November 2010, the Institute of Medicine increased their vitamin D recommendations (RDA) to 600 IU (15 ug) daily for everyone over 1 year of age and 800 IU (20 ug) daily for those over 70 years. Because of the risk of frailty and falls, the IOF recommends 800-1,000 IU daily for older adults
Vitamin A supplementation prevents death and illness in children 6 mo to 5 years of age. An editorial in JAMA published today states that further randomized-controlled trials (RCT) in children would not be ethical given the well-established benefits of supplementation – a 24% reduction in child mortality. Pretty strong stance on use of dietary supplements. This statement is derived from a meta-analysis of 43 vitamin A supplementation trials including more than 215,000 children published in BMJ. Mayo-Wilson and colleagues demonstrate the importance of vitamin A for growth and development – the essentiality of micronutrients for health. When dietary intakes are suboptimal, supplementation is an important means to acquire essential vitamins and minerals. In contrast, there have been numerous headlines this past week saying supplements are wasteful, if not dangerous to your health. What?
The Hippocratic Oath vows to prescribe regimens for the good of the patient and to never harm anyone. A single study in women diagnosed with early-stage breast cancer using self-reported dietary records found that dietary supplement use did not reduce total mortality. Another study claimed dietary supplements increased mortality in older women and in an editorial, Rita Redberg claimed “consumers are getting little value for this expenditure.” This is incorrect. Many people would benefit by changing their food choices and/or supplementing their diet to get recommended amounts of vitamins and minerals.
NPR Morning Edition broadcast a piece by Richard Knox entitled “Americans Urged to Rethink Dietary Supplement Use”. The teaser is “There’s been an explosion in the number of Americans who take vitamins and other dietary supplements. But do they do any good? And might they actually be doing harm? Two new studies raise serious questions.” Let’s put some perspective to recent events. Nobel Laureate Linus Pauling was the first to promote pharmacologic doses of nutrients (vitamin C) to mitigate disease risk, in common parlance to ‘prevent colds”. The validity of pharmacologic doses of nutrients in preventing prostate cancer and other non-communicable diseases remains controversial. This is not the topic of today's blog.
October 16 is World Food Day. DSM celebrated World Food Day and its partnership with General Mills and Cargill in Partners in Food Solutions at its Parsippany headquarters today. DSM employees were encouraged to volunteer their knowledge and expertise to help achieve food security. Jeff Dykstra, Founder of Partners in Food Solutions, opened the celebration by sharing the enrichment he and other volunteers have gained by helping small-to-medium size food production businesses in Africa. Not only is volunteerism personally fulfilling, but it the reality is that strengthening local food processing has a positive ‘ripple’ effect in the community. By helping entrepreneurial, civic-minded food companies, we are investing in the growth and future health of tomorrow’s leaders.
The Journal of Clinical Endocrinology & Metabolism (JCEM) published a meta-analysis of 26 trials with almost 48,000 participants, the majority of whom were elderly and female. Vitamin D use was associated with a significantly reduced risk of suffering at least one fall. The effect was more prominent in women who were vitamin D deficient at baseline. The same issue of JCEM has a study by Kim and colleagues who measured serum 25(OH)D levels in 3,169 Korean men and women over 50y of age. Vitamin D levels were significantly lower in subjects with sarcopenia, regardless of body mass index. Sarcopenia is the medical term for loss of muscle.
Wednesday, referred to as hump day, is the middle of a tough work week, before the slide down home to Friday and World Food Day. Today, it seems like the entire world wants to dissociate nutrition from the concept of health. Despite the tenuous links (associations) which can be drawn from epidemiological studies, or questions about the relevance of applying randomized controlled trials to study nutrients in select populations, a third study reports significant links between taking vitamins and breast cancer. Hold on a minute! Should women using vitamin supplements stop? NO! This study cannot be extrapolated to all women. Greenlee and associates studied the effect of vitamin supplementation in nearly 2,300 women who already HAD early-stage breast cancer, which had been diagnosed 2 years earlier (on average)!
Rodney Dangerfield was famous for saying “I get no respect, I tell ya.” If human, vitamin E would commiserate with Rodney. However, vitamin E isn’t human, it an essential nutrient required by humans. Today’s JAMA publication by Klein and associates will be translated into headlines that vitamin E supplements aren’t necessary, and may even be unhealthy. The report is an updated analysis of the SELECT study, the first study to directly examine if selenium and/or vitamin E supplementation may prevent prostate cancer. The results were negative for the dietary supplement industry. Do they also denigrate nutrition science and the importance of vitamin E?
Nutrients are not drugs. Nutrients do not treat, prevent or mitigate disease. Nutrients are essential to live, but they cannot prevent death. Without nutrition, people starve to death. With nutrition, we hope to live long and healthy lives. Research consistently shows that people who use dietary supplements typically exercise more regularly, smoke less, drink alcohol in moderation, and generally have healthier body weights and lifestyles. In other words, they are trying harder to follow recommended healthy behaviors.
Falling hurts. Falls cause skinned knees and lead to broken bones. Nobody wants to wear a cast. And these facts bring the topic back to nutrition. The European Food Safety Authority (EFSA) has just reviewed the science in an Article 14 submission related to vitamin D and risk of falling. The EFSA panel concluded that a cause and effect relationship existed between the intake of vitamin D and risk of falling. The EFSA panel agreed that “Vitamin D may reduce the risk of falling. Falling is a risk for bone fractures”. In order to obtain the claimed effect, the EFSA panel recommended 800 IU vitamin D daily for men and women 60 years and older. NutraIngredients.com covered the story on October 4.
The adage is “you are what you eat”, meaning if you eat well, you will be well. If you eat an unhealthy diet, you will be unhealthy. Turns out that food choice is quite habitual. The foods we eat don’t change much over time. This doesn’t bode well for nutrition education programs or our health tomorrow, next year, and in the decades to come. Boston researchers asked the question, “how much do people change their diet over time?” by studying the stability of nutrient intakes over 8 years of participants in the Framingham Nutrition Studies. Kimokoti and others published their findings online today in the European Journal of Clinical Nutrition.
Lives last longer than political administrations. But beginnings are important to both. New administrations are measured by their accomplishments during the first 100 days. A child’s future can be reflected during its first 1,000 days of life, from pregnancy to 2yrs. A paper published online Oct 3 in Archives of Pediatrics by Carmichael and associates found healthier dietary patterns during pregnancy reduced the risk of neural tube defects (NTDs) and clefts. Folic acid is one of the B vitamins, required to make DNA and RNA. Inadequate intakes of folic acid are associated with NTDs. Folate deficiencies are associated with poorer neurocognitive development and poorer neurocognitive function.
The health benefits of long-chain omega-3 polyunsaturated fatty acids (PUFA) range from supporting cardiovascular health, to cognitive functions and immunity. Recently, Meyer and Kolanu report on the typical omega-3 PUFA intakes of Australian children in a representative survey. Derivatives of omega-3 PUFAs are needed in every cell of the body. There are three main forms of omega-3 PUFA, the short-chain alpha-linolenic acid (ALA), and the long-chain eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). ALA can be converted to EPA, which in turn can be converted to DHA, however it is estimated that less than 1% of ALA is converted to DHA. This is important because DHA is often considered to be the most beneficial omega-3 PUFA.
Low vitamin D levels have been linked with many health conditions, and one of those is pain. A recent cross-sectional survey analyzed by Vasant Hirani looked closely at the relationship between vitamin D levels in older adults in the UK and levels of chronic pain. Chronic pain is a condition that has a number of causes but it is characterized by pain that lasts six months or longer. Causes of pain may be headaches, muscular and joint pain, backaches and pain from injury, and it may arise by itself or after trauma to an area of the body. The link with vitamin D levels is previous work that shows that vitamin D receptors are found in muscles, and poor vitamin D status is associated with reduced muscle strength and function, in a review by Ceglia.