Zinc
Zinc helps children thinkApril 10, 2005 Eleven-year-olds that took zinc supplements for five days each week had better mental performance after three months than their classmates, said researchers yesterday.
The children taking an extra 20mg of zinc responded more quickly and accurately on memory tasks and with more sustained attention than classmates who did not take the mineral.
Beneficial effects were seen regardless of the youngsters’ previous zinc status, said the researchers led by Dr James Penland from the US Agricultural Research Service’s Grand Forks Human Nutrition Research Center in North Dakota.
The findings, presented at the Experimental Biology meeting this week, suggest that there could be new demand for fortified foods and supplements for this age group.
Although zinc nutrition has been related to motor, cognitive and psychosocial function in very young children and adults, this is the first study of its effect in adolescents.
Zinc deficiency is not uncommon, even in nations such as the United States, and the risk is particularly high in adolescents, said Dr Penland, because they are undergoing rapid growth and often have poor eating habits. They may not consume enough zinc-rich foods like red meat, fish and grains.
Moreover the current recommended daily allowance is only 15mg for adults in the US, and up to 9.5 mg a day for men and 4-7 mg a day for women in the UK.
In the study, 111 girls and 98 boys consumed four ounces of fruit juice containing either 0, 10 or 20 mg of zinc gluconate each school day for 10 to 12 weeks. Students, their parents and teachers did not know who was receiving which, if any, zinc supplementation.
At the beginning and end of the study, students performed a battery of tasks designed to measure mental and motor skills, like attention, memory, problem-solving and hand-eye coordination.
Students, their parents, and teachers filled out questionnaires about the students’ mental, physical and social abilities and skills, school performance, and problems in any of these areas to provide a measure of psychosocial function.
Blood samples measured zinc status before and after the treatment.
Compared to the students who received no additional zinc, students who consumed an additional 20 mg zinc each day decreased reaction time on a visual memory task by 12 per cent versus 6 per cent; increased correct answers on a word recognition task by 9 per cent versus 3 per cent; and increased scores on a task requiring sustained attention and vigilance by 6 per cent versus 1 per cent.
Those who received only 10 mg a day, the US Recommended Dietary Allowances (RDA) for this age group, did not significantly improve performance, however.
Supplementation at either the 10 mg or 20 mg did not appear to improve motor and social skills, although girls receiving the placebo experienced a 10 per cent increase in conduct problems during the study while the behaviour of girls receiving any level of zinc supplementation remained unchanged, reported the researchers.
Previous studies have shown that zinc is needed for growth and immune function and may be important for eye-hand coordination and reasoning in very young children. It also appears to influence memory, muscle strength and endurance in adults.
Science Begins to Add Weight to CLA
The flurry of activity in CLA applications is being backed by a growing body of research to support the ingredient, particularly for its effects on weight loss. A review published in this month’s Journal of Nutrition supports conjugated linoleic acid’s action on weight management, concluding that it is at least in part due to regulation of glucose and fatty acid uptake and metabolism.
Conjugated linoleic acid is the common name of a group of fatty acids found in dairy products and meat. CLA isomers have been studied for their action on an impressive range of diseases, including cancer, atherosclerosis, obesity, and immune function. However as scientists begin to reveal their effects on reduction of body fat, food makers are increasingly looking at the ingredient for the valuable slimming market.
In Canada, where many of the patents for CLA are held, the dairy industry has long been studying the production of high-CLA milk. In Europe, a research centre in Ireland is studying the compound which could add significant value to its dairy industry, while in Italy, Techno Foods introduced a strawberry flavoured yoghurt naturally rich in CLA (conjugated linoleic acid) and omega-3 fatty acids this summer.
Specific CLA isomers have been shown to prevent the development of obesity in certain rodent and pig models and this has been attributed mainly to trans-10, cis-12 CLA, both in vivo and in vitro, write the University of North Carolina researchers in the review. However, CLA’s ability to modulate human obesity remains controversial because data from clinical trials using mixed isomers are conflicting.
In vitro studies by the team demonstrated that while trans-10, cis-12 CLA prevents triglyceride accumulation in human cells, cis-9, trans-11 CLA increases triglyceride content. The team concluded that the isomers’ regulation of glucose and metabolism must partly explain its mechanism on human fat.
The news is also good for supplement marketers who recently learned of research carried out by Cognis backing the long-term safety of its Tonalin CLA.
Probiotics for Health
Probiotics for Health By S.K. Dash, Ph.D.
Many health-conscious consumers today want to know when they should take probiotics. They ask whether they should wait until they are sick. If so, they ask, which illnesses respond best to probiotics? Or should they take a preventive approach and take probiotics before they get sick? What about use of probiotics with antibiotics? Today, there is no doubt that taking probiotics is as essential as a multivitamin to your health. So my reply to such questions is that a daily supplement should always be taken to maintain healthy immune and digestive function — but the supplement amount should be increased during times of stress and illness. But let’s start at the beginning.
Probiotics — What Are They?
The concept of ingesting live microorganisms for the purpose of improving one’s intestinal health and general well being can be traced back well before the beginning of the Twentieth Century to earlier eras when most foods were nonrefrigerated and instead preserved with fermentation. But the current practice of using beneficial organisms to improve and sustain health is now referred to as probiotic supplementation. Although numerous types of bacteria (and yeasts) are currently being marketed as probiotic cultures throughout the world, the two most commonly used ones are Lactobacillus and Bifidobacterium.
Probiotics — A Health Essential?
Consumers rarely consider how essential healthy bacterial populations are to their health. But the fact is that a healthy ratio of beneficial to pathogenic bacteria residing within the gastrointestinal tract is essential to good health and influences not only digestive health but also immune function, detoxification, and women’s vaginal health. Unfortunately, great numbers of people today no longer have optimally balanced ratios of beneficial to pathogenic bacteria in their body, thus allowing the “”bad guys”" to gain the upper hand. This is very dangerous and one of the reasons that digestive illnesses, as well as other types of illnesses, are becoming so prevalent. Medically prescribed antibiotic use is certainly one of the most important causes of this change in our natural flora, with travel to foreign lands a close second. But beyond these detrimental impacts on our gastrointestinal health, we face many other daunting challenges to our bacterial balance. Unless one consumes organic dairy products, for example, one is almost certainly consuming traces of antibiotics and sulfa drugs, which have a disruptive effect on bowel ecology. Our highly processed food supply has also denied our bodies the opportunity to ingest beneficial bacteria as we once did through food fermentation (widely used before refrigeration). Our water also tends to be highly chlorinated which, although important from a public health perspective, has drawbacks for individual health when it comes to adversely impacting our body’s bacterial populations. When the body’s bacterial populations are upset, many kinds of illness can result. So for daily maintenance and in times of illness it just makes sense to use a quality probiotic formula.
Prevention and Treatment of Diarrhea and Constipation: Antibiotic-associated diarrhea can be attributed in part to imbalances in intestinal microflora. Bifidobacteria have been used to successfully treat intestinal disorders and in the prevention of rotaviral diarrhea in children and adults. In fact, taking a probiotic formula with antibiotics is now considered to be standard medicine in many countries. But antibiotics and probiotics must be taken a few hours apart. Constipation is a significant problem for many people, especially the elderly. Researchers have shown that enhancing Bifidobacteria in the large intestine of constipated elderly individuals provides a significant laxative effect.
Ulcer Therapy: If you’re taking antibiotics to treat your ulcer, you should be using probiotics along with your doctor’s prescribed antibiotics. That’s the message from researchers reporting in the February 2001 issue of Digestion. Frequently, nausea, bloating, diarrhea, taste disturbances and loss of appetite are side effects from use of antibiotics to eradicate Helicobacter pylori, the bacterium thought to be the causative agent in gastric ulcers. This latest study involving 120 ulcer patients shows that persons given both antibiotics and probiotics experienced markedly reduced incidence of bloating, diarrhea and taste disturbances compared to persons given only antibiotics, and most persons given the natural remedy experienced no side effects.
Enhanced Immune Function: Most of our immune cells are produced within the gastrointestinal tract and much of our protection against orally ingested pathogens (such as salmonella) is the result of a healthy gastrointestinal environment. There is perhaps no greater protection against such food-borne pathogens than the use of probiotics to sustain this healthy environment. Recent studies show that Lactobacilli and Bifidobacteria can stimulate both general immunity and also specific antibodies to certain pathogens.
Lactose Intolerance: Dairy foods are a very important part of a healthy diet, but many of us suffer from some symptoms of lactose intolerance. Studies have shown that strains of Lactobaccilli and Bifidobacteria reduce symptoms of lactose malabsorption.
Establishment of Healthy Flora: in Babies and Infants Premature infants generally take longer to establish a characteristic intestinal flora, which can render them more susceptible to certain intestinal infections. Various strains of Bifidobacterium administered to premature infants results in populations of beneficial bacteria becoming established more quickly in their intestines compared to a control group. You will also likely find that children susceptible to middle ear infections enjoy better health when they are given probiotics (DDS®-Junior Probiotic for Children).
Editor’s Note: Dr. S. K. Dash is among the world’s leading experts today in the field of probiotics. Dr. Dash is founder of America’s leading probiotic company UAS Labs.
See the full unabridged version of this article at www.freedompressonline.com.
References Armuzzi, A., et al. “”Effect of Lactobacillus GG supplementation on antibiotic-associated gastrointestinal side effects during Helicobacter pylori eradication therapy: a pilot study.”" Digestion, 2001;63:1