3 July 2009
Highest rates in South Asia and the Middle East
A new report issued by the International Osteoporosis Foundation (IOF) and published in the scientific journal Osteoporosis International1, shows that populations across the globe are suffering from the impact of low levels of vitamin D. The problem is widespread and on the increase, with potentially severe repercussions for overall health and fracture rates.
Compiled by IOF's expert working group on nutrition, the report reviews the scope and causes of low vitamin D levels in six regions: Asia, Europe, Latin America, Middle East and Africa, North America and Oceania. Regional reports are available on the IOF website
Vitamin D is mainly produced in the skin upon exposure to sunlight, and, to a lesser extent, is derived from nutritional sources. It plays an important role, through its influence on calcium levels, in the maintenance of organ systems, and is needed for normal bone mineralization and growth. Suboptimal levels of vitamin D may lead to increased risk of osteoporosis and hip fracture and, in severe cases, to the development of rickets, a softening of bones in children that can lead to skeletal fractures and deformity.
Although there is ongoing debate as to what constitutes the optimal level of vitamin D, the report shows that regardless of whether it is defined at 50nmol/L or 75nmol/L, vitamin D status is seriously inadequate in large proportions of the population across the globe.
The main risk factors for low vitamin D levels include older age, female sex, lower latitudes, winter season, darker skin pigmentation, less sunlight exposure, dietary habits, and the absence of vitamin D fortification in common foods. Further factors include the increase in urbanization, where people tend to live and work indoors, as well as cultural practices that tend towards sun avoidance and the wearing of traditional clothing that covers the skin. The severity of the problem in Middle East and South Asia arises from the combination of several of these risk factors.
These findings suggest that prevention strategies must be initiated at the national level - especially given the increasing ageing of populations in many regions of the world. National plans of action should encourage safe, limited exposure to sunlight and improved dietary intake of vitamin D, whilst considering fortification of foods as well.
Omega-3s sourced from krill are more effective than fish oil in combating some metabolic symptoms including raised fat levels in the heart and liver and violent mood swings in obese individuals, according to Italian researchers.
The study, to be published in the August edition of the Journal of Nutrition, is supported by Norwegian krill supplier, Aker Biomarine, and concludes that while both fish-sourced and krill-sourced omega-3 oils are effective in reducing fat levels, krill is more effective.
The researchers, led by Barbara Batetta, said the mechanisms of why this was the case had not been made clear in the study, but suggested long-chain polyunsaturated fatty acids (LCPUFAs) may reduce activity in the endocannabinoid system.
The endocannabinoid system consists of a group of neuromodulatory lipids and receptors that influence appetite, pain sensation, mood and memory.
“Whereas CB1 (cannabinoid receptor type 1) receptor antagonists dampen the overactivated endocannabionid system by blocking the receptor, dietary (n-3) LCPUFA, and KO (krill oil) in particular, may reduce the activity of the endocannabinoid system by decreasing the substrate availability for endocannabinoid biosynthesis,” the researchers said.
“Such a nutritional approach, if influencing the endocannabinoid system only peripherally, might avoid the adverse psychiatric effects associated with the use of CB1 antagonists, thus potentially providing a safer alternative for ‘endocannabinoid reequilibration’ in obese individuals.”
The researchers found that, when parameters associated with obesity were considered, Aker Biomarine’s version of krill oil reduced rat heart fat levels by 42 per cent, compared to two per cent for fish oils.
In the liver, a 60 per cent reduction was observed for krill, 38 per cent for fish oil. Fat build up in the liver can lead to insulin insensitivity and cause type-2 diabetes.
While the exact mechanism for change could not be isolated the researchers stated: “It is worth noting that in all tissues exhibiting changes in endocannabinoid concentrations, EPA and DHA concentrations in the PL (phospholipid) fraction were increased and the increase was greater in the KO compared with FO (fish oil)-supplemented rats.”
The four-week-old Zucker rats were for four weeks fed either a diet of KO or FO balanced for eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), or a control group with no EPA and DHA but similar contents of oleic, linoleic, and a-linolenic acids. The dosage level was set at 2g of DHA/EPA per day.
Eighteen rats were used.
In designing the study, the researchers speculated that obesity could be linked to visceral adipose tissue (VAT) accumulation and that the metabolic consequences of that could be down to dysregulation of the endocannabinoid system and CB1 receptors.
Source: Journal of Nutrition (August)
Published ahead of print June 23, 2009 as doi: 10.3945/jn.109.104844.
‘Endocannabinoids May Mediate the Ability of (n-3) Fatty Acids to Reduce Ectopic Fat and Inflammatory Mediators in Obese Zucker Rats’
There are many reasons that some people choose to shop and eat a completely organic range of foods, but the primary reason seems to center around the additives in various non-organic food items. Those additives have been studied and linked to various diseases, and instead of taking the chance that unhealthy preservatives and flavorings might be integrated into grocery store items, people often opt for the strictly organic route so as to avoid them altogether.
But everyone cannot afford the prices of organic foods or the time it takes to shop at specialty markets for them. Thus, becoming informed about the additives in everyday food items can make for an easier shopping experience and healthier items being ingested by everyone. In addition, a mass boycott of foods that contain such additives could prompt food manufacturers to remove such harmful ingredients from their products in the future.
Thanks to MSN Health & Fitness contributor Jean Weiss, a list of the most medically questionable and harmful additives in everyday foods has been compiled to educate the masses. There are several that may be recognizable due to news reports and popular opinion, but others may be new to some and worthy of notation.
One of the most common additives in food is the preservative, which can come in different forms. Sodium nitrite is one of them, as it is added to not only preserve food but to add color and flavor to meat products, most commonly bacon, ham, hot dogs, sandwich meats, and smoked fish. BHA (butylated hydroxyanisole) and BHT (butylated hydrozyttoluene) are other preservatives added to foods like cereal, gum, potato chips, and vegetable oils to prevent them from oxidizing. And propyl gallate has similar de-oxidizing values and is found in meats, chicken soup base, and gum. All of these preservatives have been found to cause cancer through certain types of food preparation, such as cooking meat at high temperatures. Though the studies are not conclusive and mostly conducted on animals, all of them contain reactive compounds that can be harmful.
As far as flavoring, monosodium glutamate (MSG) used to be a very common amino acid used in restaurant foods, soups, and salad dressings, though most food preparers and manufacturers have removed it from their list of ingredients. Beware of canned and frozen foods that still may attempt to use it, as MSG can cause migraines and other adverse effects. Trans fats are also being eliminated from most foods, as the studies linking them to heart disease, strokes, and kidney problems are widely-accepted.
Sweeteners are another item to avoid when possible. Aspartame is found in products like Nutrasweet and Equal as well as diet foods and soft drinks. And acesulfame-K is a newer sweetener used in soft drinks and some baked goods. These products, only preliminarily linked to cancer, have the same negative nutritional value as white sugar, all of which should be minimized in any diet.
Many food colorings have been banned by the FDA but some can still be found in foods that require a particular color. And Olestra is a product also discouraged by health food organizations that is rarely used anymore, though was common for a time in potato chips as an additive that prevented fat from being absorbed in the digestive system. Each of these items should be avoided at all costs, as the food colorings have been tied to cancer and Olestra simply blocks vitamins from being processed through the body and blocks the digestive process from functioning normally.
Potassium bromate is sometimes added to white flour, breads, and rolls to increase the volume of the products, but there are cancer-causing properties that have prompted some states in America to actually require a label to that effect.
Finally, sodium chloride is also known as salt, and though it is a common additive in many—if not most—foods, it can be dangerous if not kept to a minimum. Large doses can lead to heart and blood pressure problems, as well as strokes and kidney failure.
30 June 2009
Smog is nasty enough in the atmosphere, but now research suggests that ozone, a key component of smog, stresses out human skin cells.
Cars and factories belch pollutants into the air that combine with the sun's rays to form photochemical smog. Ozone in the lower atmosphere contributes to the smog that's visible to the eye; this is different from ozone high in the atmosphere that helps protect life on Earth from deadly doses of ultraviolet solar radiation.
Researchers at the University of Wisconsin, Madison, exposed human skin cells to the smog-related ozone in the laboratory and found that they turned on cellular machinery that normally responds to stress, suggesting ozone may be toxic to human skin. However, further experiments are required to confirm the findings in people.
Smog breaks down into free radicals when zapped by the sun. These free radicals bounce around inside cells like pinballs, destroying most of the "machinery" they hit. Free radical damage has been implicated in diseases such as cancer, heart disease, Alzheimer's disease and Parkinson's disease.
While smog's damaging effects on our respiratory system have been well studied, little is known about how smog affects our skin, even though urban and suburban residents are repeatedly exposed to ozone on smoggy days.
The lab research involved isolating and exposing normal skin cells to ozone at 0.3 parts per million. Typical ozone levels in big cities can range from 0.2 to 1.2 ppm.
In the lab, ozone exposure boosted the activity of enzymes that convert environmental pollutants and cigarette smoke to more toxic compounds.
The study was published in the June 18 issue of the Journal of Investigative Dermatology.
Tease your brain
Lack of education is a strong predictor of cognitive decline. The more you've tried to learn, the better off you'll be in old age.
Stress takes a toll on your brain by washing harmful chemicals over the hippocampus and other brain areas involved in memory. Some scientists suspect that living a balanced lifestyle and pursuing relaxing activities such as yoga, socializing and crafting may delay memory impairment by reducing stress.
Essential fatty acids, such as Omega 3’s, are critical to brain function and are proving beneficial for treating such brain-sapping ailments as depression.
Get your beauty rest
When you rest and dream, memories are sifted through, some discarded, others consolidated and saved. When you don't sleep, proteins build up on synapses, possibly making it hard to think and learn new things.
Take care of your body
Preventable diseases -- such as Type II diabetes, obesity and hypertension -- all affect your brain. System-wide health concerns have been linked to an increased risk of cognitive decline and memory impairments.
Watch your diet
Too much or too little energy throws a kink in your brain’s delicate machinery. A steady pace of digestion in your gut gives a more reliable flow of energy to your brain, likely optimizing the organ's long-term health and performance.
Scientists are starting to think that regular aerobic exercise may be the single most important thing you can do for the long-term health of your brain. While the heart and lungs respond loudly to a sprint on the treadmill, the brain is quietly getting fitter with each step, too.
29 June 2009
Young adults are not drinking enough milk, according to a study published in the July/August issue of the Journal of Nutrition Education and Behavior by researchers from the University of Minnesota, Minneapolis.
Well, at least that's according to the press release about the study, along with a few press reports on the matter. But according to lead author Nicole Larson, the focus on the study was on calcium.
Once again, we see the words "milk" and "calcium" used interchangeably in the popular press. Milk is a calcium source, but by no standard other than that of the National Dairy Council is it the best calcium source.
Hard to swallow
This study, an important one, found that during the transition from middle adolescence to young adulthood, females and males reduced daily calcium intakes by an average of 153 milligrams and 194 milligrams, respectively.
This is indeed troublesome because peak bone mass isn't reached until the early 20s. Like a retirement fund, you have to start banking your calcium early because you will lose it slowly later in life.
How much calcium we need is an open-ended question. The recommended level is 1,300 milligrams for ages 9 through 18; 1,000 milligrams for ages 19 through 50; and 1,200 milligrams for ages over 51.
Yes, older kids stop drinking milk. That's to be expected. As delicious as dairy products can be, to suggest that we need to drink three glasses of the secretion of a cow's mammary glands in order to be healthy is a bit outrageous and doesn't fit our evolutionary profile. If fact, most of the world, aside from a group of minorities called white people, cannot easily digest cow milk.
We do need calcium, though, and there are plenty of ways to get enough.
The recommended level of over 1,000 milligrams is a U.S. standard based largely on how lazy we are and how much meat we eat. Weight-bearing movements such as walking strengthen bones by increasing calcium uptake and by signaling bone cells to maintain calcium stores. Too much protein might be associated with calcium leaching and higher fracture rates. This is according to the Harvard-led Nurses' Health Study and other studies, although the results do remain controversial.
Numerous studies have found no association between high calcium intake and lower fracture risk. Regardless, a milk-free diet won't leave you deprived of calcium. Yogurt has more calcium than milk and is easier to digest. Collards and other greens also have about as much or more calcium than milk by the cup. Greens, unlike milk, have the added benefit of vitamin K, also necessary for strong bones. Tofu and sesame are also very high in calcium.
When you measure calcium by cup of food product, milk is high on the list. When you view it by calorie, though, milk is at the bottom. A hundred calories of turnip greens have over three times as much calcium as 100 calories of whole milk, for example.
What non-milk calcium sources lack, usually, is the saturated fat. Recommendations to drink more milk concern the low-fat variety, which few of us like.
Who to trust
Studies on milk's usefulness vary by advocacy group. A study published in 2005 in Pediatrics by the pro-vegetarian Physicians Committee for Responsible Medicine concluded that "scant evidence supports nutrition guidelines focused specifically on increasing milk... for promoting child and adolescent bone mineralization." A study published in 2006 in the Journal of Dairy Science by the National Dairy Council reports how milk builds strong bones, lowers blood pressure, contributes to weight loss and body fat reduction and protects against several kinds of cancer.
Who can you believe? Likely not the latter. But the other extreme is off the mark, too.
For example, some vegans state that milk causes osteoporosis, or weak bones. They point out how the Inuit eat protein-heavy diets and have the highest rate of osteoporosis in the world. If this is true, it would more likely be due to the Inuit's minimal exposure to sunlight (missing half of the year) and dark skin, which blocks ultraviolet light. UV is needed to manufacture vitamin D in the skin, crucial for strong bones and more.