The New England Journal of Medicine published a comparison of two drugs on the progression of advanced-macular degeneration (AMD) Apr 28, 2011. The primary outcome was mean change in visual acuity over 1 year of treatment. There was not a placebo treatment. Ranibizumab cost $2,000 per treatment and bevacizumab cost $50 per treatment. The drug treatments did increase visual acuity with mean gains of 5.9 and 6.8 letters but almost 25% of the patients had serious systemic adverse events, primarily hospitalizations. AMD is a leading cause of blindness. Pharmaceutical companies, physicians, and patients all want treatments
Archive for 'April 2011'
Weight management isn’t easy. And changes in metabolism associated with aging further reduce the number of calories needed to maintain energy balance. Thus, the recent meta-analysis of a vegetable oil emulsion showing a small appetite suppressing effect is of interest. Between 1971 to 2006, the prevalence of obesity increased from 11.92% to 33.4% in men and 16.6% to 36.5% in women. Austin, Ogden and Hill reported that energy intake increased as well with a reduction in the proportion of calories consumed from fat and protein. They recommended that dietary interventions should focus on decreasing energy intake.
De Medeiros and co-workers report on antioxidant nutrient intakes in a cross-sectional study in 2344 Brazilians. They analyzed 24-hour dietary recall data from a study in older adults in 150 Brazilian cities to determine whether intakes of the antioxidant micronutrients vitamins A, C and E, and selenium and zinc, met nutritional guidelines in people not taking supplements. Adequate intakes of antioxidants fulfill dietary needs, and provide protection from oxidative stress, which may be beneficial in preventing chronic diseases.
Some people have blue eyes, some brown, and others have green eyes. Just as there are polymorphisms in the genotype eye color, Crider and colleagues studied polymorphisms in the 5-methyltetrahydrolate reductase (MTHFR) enzyme in 932 Chinese women. The MTHFR enzyme is important nutritionally because it plays a key role in one-carbon metabolism and is sensitive to dietary folate insufficiency. Three common MTHFR genotypes have been identified: CC, CT, and TT. In the Apr 20 American Journal of Clinical Nutrition paper, Crider and colleagues reported: 47.5% heterozygous for CT with 17% and 35% were homozygous for CC and TT, respectively Individuals with TT genotype had lower red blood cell (RBC) folate and higher homocysteine concentrations than those with CC and CT genotypes Folic acid supplementation consistently increased RBC folate and decreased homocysteine levels, even in individuals with TT genotype
Bolland and colleagues studied the effects of personal use of calcium supplements with or without vitamin D on cardiovascular risk in 36,282 women (Women’s Health Initiative) over 7 years. In the 46% of women not taking personal calcium supplements at randomization, they found supplementation (1 gram calcium and 400 IU vitamin D daily) increased risk whereas it did not in those taking calcium supplements at baseline. They concluded that calcium supplements, with or without vitamin D, may modestly increase the risk of a cardiovascular event. Although not discussed, the hazard ratio for death from all causes actually decreased 16% in individuals who started taking both calcium and vitamin D. This meta-analysis raises more questions than it provides answers. The study has been questioned because
The chances are, they may be missing out, according to Harika and associates, publishing a 30-country comparison in the British Journal of Nutrition. They conducted a large systematic review of saturated fatty acid (SFA), mono-unsaturated fatty acid (MFA) and polyunsaturated fatty acid (PUFA) intakes in children and adolescents. Fatty acid consumption is important for children and adolescents’ future cardiovascular health, particularly the omega-3 fatty acids, docosohexaenoic acid (DHA) and eicosapentaenoic acid (EPA). The authors searched research databases to find national data on fat consumption in children and adolescents. Most research has been conducted in developed countries.
Labadarios and colleagues investigated the variety of South Africans’ diets in a recent survey published in Nutrition Journal. Dietary guidelines normally recommend variety as the best way to ensure complete nutrition. No single food provides adequate levels of all nutrients and micronutrients, and eating from different food groups adds interest to the diet. South Africa is no exception, even though it is a developing country. The first of South Africa’s ten dietary guidelines is “Enjoy a variety of foods”.
Karen Woolley et al examined 520 papers found in Medline between 1966 and 2008 which were retracted and identified 463 which had been both retracted and had an online retraction notice. They found that 46% of these scientific studies were retracted because of misconduct rather than errors. Ivan Oransky wrote in Retraction Watch that “papers which did not receive industry support were a whopping 3.7 times more likely to be retracted for misconduct than for an error”.
The National Toxicology Program within the Department of Health and Human Services has a broad mandate to evaluate substances of public health concern, to develop methods and approaches to characterize chemicals and agents of public health concern, including food additives, and to communicate their findings to stakeholders. The Board of Scientific Counselors will be meeting July 21-22 where they will discuss a proposal to evaluate the potential health effects of excess folic acid. Folic acid has no established toxicity in humans.
With the April 13 2011 release of the CDC report that 50% of US adults now use dietary supplements, there has been a media avalanche with CBS News, Washington Post, Los Angeles Times, WebMD, and others generating headlines. People are imitating the behaviors of their health care professionals.
Drs R Perez-Escamilla and Dr O Bermudez co-chaired the ASN-Minority Affairs Committee (ASN-MARC) Symposium at EB 2011 on Health and Nutrition Disparities on Tuesday, April 12. Click here to listen to Dr Perez-Escamilla’s video summary where he discusses the root of disparities. This is the second year that the ASN-MARC has had a scientific session at EB. Dr K Lancaster and O Bermudez recently published an introduction to last year’s discussion of nutrition and health disparities at EB in the American Journal of Clinical Nutrition.
Large scale vitamin trials have generally not been able to show the benefits expected from observational and pre-clinical research. Why is this so?
Lots of news around the benefits of DHA and EPA this week. A vote by the European Parliament endorsed the claim that DHA, a fatty acid naturally occurring in breast milk, “contributes to the normal visual developments of infants up to 12 months of age”. Of course there are benefits of having adequate intakes of DHA and EPA beyond 12 months of age. This is the reason
New data was presented at EB2011 on nutrient disparities in adult US subpopulations by ethnicity and socioeconomic status. Building upon “What We Eat in America” using NHANES 2001-2002 and NHANES 2005-2006 which identified vitamins A, C, E, magnesium, calcium, dietary fiber and potassium as nutrients of concern, Drs Fulgoni and McBurney examined the effect of ethnicity (White, Mexican American, or Black) and socioeconomic status (household income < poverty index ratio (PIR) or > PIR) using NHANES 2003-2008 on nutrient adequacy.
Many women experience physical and emotional symptoms as they age and experience changes in their menstrual cycle. This is called premenstrual syndrome (PMS). A study by Dr E Bertone-Johnson published in the American Journal of Clinical Nutrition examined vitamin intakes of 1,057 women with and 1,968 women without premenstrual syndrome (PMS). Women (25-42y) with the highest intake of riboflavin and thiamin had a 35% lower risk of developing PMS compared to those with average intakes. In older women, postmenopausal symptoms can be a challenge.
A new review proposes that vitamin E improves insulin sensitivity. The authors emphasize that alpha- and gamma-tocopherol are structurally similar to drugs (thiazolidinediones or TZDs) used since the 1990’s to treat insulin resistance and type 2 diabetes. Almost two decades ago, G Paolisso and associates published that vitamin E supplementation improved glucose metabolism in elderly people. J Salonen and associates studied 944 Finnish men aged 42-50 years old without diabetes for 4 years and reported in 1995 that low vitamin E status was associated with increased risk of diabetes mellitus.
Who would believe that Australians with their climate would be vitamin D deficient? However, 41% of pregnant women in Australia studied were vitamin D deficient (serum 25(OH)D < 50 nmol/L). And, Dr J Gunton and colleagues reported that low serum 25(OH)D levels were associated with higher fasting and 2 hour blood glucose levels after an oral glucose tolerance test (OGTT), a measure of gestational diabetes. Lower 25(OH)D levels were independently associated with poorer glycemic control. The authors identified the need for randomized controlled trials to determine if vitamin D plays a causal role in gestational diabetes. Approximately 6-10% of pregnant women in Australia develop gestational diabetes.
After two days of meetings, an FDA Food Advisory Committee, chaired by Dr Gary Acuff from Texas A&M University, determined in an 11 to 3 vote that there is not enough evidence to conclude that artificial dyes used in foods and beverages contribute to hyperactivity in children. In addition, the Committee voted 8 to 6 that products containing artificial dyes do not need warning labels. The FDA is expected to make a decision on this recommendation.