Archive for the ‘Others’ Category

Clearing some confusions on Vit D

Wednesday, July 17th, 2013

Why is Vit D important?

Vit D is appearing in many peer-reviewed journals these days. especially in cardiology, endocrine and cancer journals. Low vitamin D status has been associated with cardiovascular disease, certain cancers, cognitive decline, depression, diabetes, pregnancy complications, autoimmune diseases and even a 78 percent increase in all-cause mortality risk (<17.8 ng/ml 25(OH)D compared to >32.1 ng/ml)

What is the current RDA?

In 2010, the IOM decided to revise and raise the DRI for vit D. This is now the official US government position adopted by the Food and Nutrition Board.. These guidelines are still low compared to those recommended by the Endocrine Society and the Vit D Council.

 

  Vitamin D Council Endocrine Society Food and Nutrition Board
Infants 1,000 IU/day 400-1,000 IU/day 400 IU/day
Children 1,000 IU/day per 25lbs of body weight 600-1,000 IU/day 600 IU/day
Adults 5,000 IU/day 1,500-2,000 IU/day 600 IU/day, 800 IU/day for seniors
Recommended daily intakes from various organizations:

 

 

What is the best test for Vit D deficiency and why?

The accepted blood test is 25OHD3 and the range accepted by the current pundits is

vitD3

 

 

 

 

To understand which of the metabolites of Vit D is the best for clinical measure, one need to understand the natural synthesis of Vit D and the various metabolites.

 vitD1vitD2

 Vit D is derived from 2 sources: the skin and dietary source. The precursor of Vit D is a cholesterol derivative, 7 dehydrocholesterol and it is converted via UVB component of sunlight to vit D3 (cholecalciferol – inactive unhydroxylated form). Likewise, diet rich in Vit D such as milk and fish is digested and absorbed as Vit D3. It is then converted to 25OHD3 (Calcifediol or Calcidiol) in the liver and further converted to the physiologically active 1,25 OH2D3 (Calcitriol) in the kidney. This process has many cofactors and regulates level of Calcium and Phosphate via the PTH hormone through the bone and intestine. Why don’t we use the physiologically active 1,25 OH2 D3 as the measure of deficiency in the body? Although cholecalciferol and 1,25(OH)2D3 (calcitriol) can be measured in the circulation, the best estimates of vitamin D status are provided by measurement of 25OHD3 (calcidiol). This is due to its long serum half-life (approximately 3 weeks) and because the 25-hydroxylation step is unregulated, thus reflecting substrate availability. A number of commercial kit assays are available for the clinical laboratory.

In contrast, cholecalciferol has a short half-life (approximately 24 h) so that serum levels depend on recent sunlight exposure and vitamin D ingestion and is a better indicator of the conversion phase in the kidney, hence kidney function.. The assay is difficult due to the lipophilic nature of the molecule and no commercial versions are available.

What is the optimal level of 25OHD3 to ensure optimal health?

The challenges today with 25OHVit D3 is the lack of standardization of the measure and even if we have a sense of the level of storage in the body, it is not useful as a clinical tool as there are so many functions of the active 1,25 OH vit D3 in particular bone and immune health. By the time we get to osteoporosis and cancer to evaluate its level, it would have been too late. There seems to be a suggestion that the level adequate for the prevention of osteoporosis (some suggest 30 ng/ml calcidiol) may not be high enough for cancer prevention (some suggest 50 ng/ml calcidiol). Therefore there is a need for better downstream functional markers of Vit D3 in various diseases for the measure to be clinical relevant and useful. One thing is certain, it is not recommended that the level of 25OHD3 exceeds 150 ng/ml which is the maximal tolerable level when toxicity will set in.

Current forms of Vit D supplements and what should be the target level:

 The other issue is that most supplements sold in the US and Australia are plant based vit D2. Ergocalciferol (vitamin D2) is produced commercially by ultraviolet irradiation of a provitamin D sterol (ergosterol) that occurs in plants. It differs from vitamin D3 in having an additional methyl group at C24 and a double bond at C22-23. It undergoes the same hydroxylation reactions as cholecalciferol to form 25OHD2 and 1,25(OH)2D2. Ergocalciferol is the only prescription pharmaceutical available in Australia and the only high dose preparation available in the USA so D2 metabolites can represent a significant fraction of the circulating hormone in patients treated with these preparations. Not all available lab tests could measure 25OHD2.

Furthermore, the half life of 25OHD2 is shorter and clinical potency is less than one third of 25OHD3. Most vit D supplements in Europe and Asia are now in D3 form.  I certainly would recommend the D3 form for those who are keen on supplementation. I would also encourage that the 25OHD3 be kept at about 30-60 ng/ml for optimal health, in particular in boosting immune health and prevent cancer.

Millions May Be Taking Vitamin D Unnecessarily, Analysis Suggests

Thursday, October 25th, 2012

Under the latest guidelines from the Institute of Medicine, it’s possible that almost 80 million Americans who’ve previously been considered as having low levels of vitamin D don’t need supplements of this nutrient at all, according to a new study.

Older guidelines had suggested that anyone with a blood level of vitamin D that was less than 30 nanograms per milliliter (ng/mL) needed to boost their levels, but the newer Institute of Medicine (IOM) guidelines say that a minimum level of 20 ng/mL is sufficient.

However, not all experts agree with the new guidelines from the IOM, a nonprofit American organization that dispenses health advice.

“The IOM guidelines are so different than the Endocrine Society’s guidelines that this study will just add to the controversy,” said lead study author Dr. Holly Kramer, an associate professor of medicine at Loyola University Medical Center in Maywood, Ill. “We really need clinical trials to settle the whole issue, but what’s clear is that these threshold levels make a huge difference in how many people would be taking vitamin D.”

The Endocrine Society is an international group of endocrinologists.

Why worry about your vitamin D intake? Vitamin D is essential for good bone health, and it’s necessary to prevent the disease known as rickets. The nutrient has also been implicated as potentially beneficial for a number of conditions. Low levels of vitamin D have been associated with higher risks of some autoimmune diseases, and may make people more susceptible to infection.

In addition, noted Dr. Robert Heaney, a professor of medicine at Creighton University in Omaha, Neb., low vitamin D has also been associated with high blood pressure, insulin resistance and the metabolic syndrome — a group of symptoms that signal higher risk for diabetes and heart disease.

Heaney is a member of the Endocrine Society’s task force on vitamin D guidelines.

“Vitamin D is necessary in most cells in our body, probably all cells,” Heaney said. “When you have adequate vitamin D, all of the body’s systems tend to work well.” But, “there is no consensus on what normal levels are in the field of nutrition,” he added.

For the current study, Kramer and her colleagues reviewed data on more than 15,000 adults from the third U.S. National Health and Nutrition Examination Survey and linked that information to 18 years of information from the National Death Index to determine if vitamin D had an effect on mortality rates.

The researchers found that in people with impaired kidney function, about 35 percent had vitamin D levels below 20 ng/mL. In people with healthy kidneys, about 30 percent had levels below 20 ng/mL, according to the study.

But for the older, higher vitamin D threshold, 76.5 percent of people with impaired kidney function would be considered to have low levels of vitamin D, as would 70.5 percent of people with healthy kidneys.

“Even under the new guidelines, there are still a fair number of people who are considered deficient or insufficient,” Kramer said.

There was a big difference in mortality rates for those who had the lowest levels of vitamin D — less than 12 ng/mL — compared to those with levels between 24 and 30 ng/mL. But after that, Kramer said, there wasn’t much difference in mortality between the groups.

Heaney also noted how findings varied according to vitamin D levels.

He said that while there wasn’t a huge effect from group to group depending on vitamin D levels, there was “a continuing downward trend” with less mortality as vitamin D levels went up.

So where does that leave people trying to decide whether to take the supplements?

Kramer said that right now the decision may depend on your personal situation, and suggested talking to your doctor about whether extra vitamin D is necessary for you. People with certain medical conditions need to be on vitamin D. But, she said that others are taking supplements who don’t need to and that it’s just a waste of their money.

For his part, Heaney noted that taking vitamin D and other nutrients may be akin to changing the oil in your car. “If you don’t change the oil, your car runs well now, but it may break down sooner,” he said.

In terms of side effects, Kramer said, too much vitamin D can increase the risk of kidney stones, but in general, it’s a well-tolerated supplement. The upper safe limit for daily intake is 4,000 international units, according to the U.S. Office of Dietary Supplements, though most people take a much lower dose.

MASSAGE COULD REVERSE MUSCLE DAMAGE IN MINUTES

Friday, July 6th, 2012

Nothing feels better than a hard-earned massage to tame tension and curb nagging pain—but you might be surprised at just how much relief that rubdown can give your overworked muscles. Believe it or not, research shows that you could get serious cellular support against underlying inflammation within mere minutes, just by turning your aching b/dy over to professional hands.

Ten Minutes Is All It Takes

As part of a new study published in February 2012, researchers at McMaster University decided to take a closer look at exactly how massage works to relieve pain and restore damaged muscles. To do this, they assessed the exercise capacity of 11 men in their early 20s, after which each subject exercised to exhaustion on a bicycle for a total workout time of over 70 minutes.

A therapist then applied massage oil to both of each of the subjects’ legs during a brief, 10-minute rest period,kperforming a massage on one thigh muscle while leaving the other leg untreated as a control. Researchers took muscle biopsies from the subjects’ quadriceps before the exercise, immediately following this 10-minute massage, and then again two-and-a-half hours later.

The results of this laboratory analysis? In just 10 short minutes, therapeutic massage helped to reverse over an hour’s worth of exercise-induced muscle damage, one cell at a time.{{{0}}}

Soothe Inflammation and Power Up Your Cells

While the value of massage as a tension-busting, pain-relieving therapy is well established, this study is the first of its kind to explore the biochemical mechanisms behind massage’s time-tested benefits. And, as it turns out, stretching and manipulation signals more than one mode of healing within your muscles’ cellular infrastructure.

The McMaster researchers found that massage was able to stifle rises in NFkappaB, TNF-alpha and interleukin-6 (IL-6)—three cell-signaling factors that play a major role in the inflammatory cascade that follows exercise-induced muscle trauma. What’s more, the biopsies also showed an increase in mitochondrial biogenesis signaling—suggesting that massage sends messages to the body to create more mitochondria, the structures that serve as cellular power hubs.1-2

The end result of this chemical activity is a significant reduction in muscular inflammation, paired with less cellular stress and revitalized cellular energy, delivering pain relief via the same biochemical processes you’ll see with many pain medications. Given this ability, the study authors offer massage as one promising route to speedier injury recovery—not to mention its potential against other chronic diseases linked to muscular inflammation, such as arthritis and muscular dystrophy.

Either way, it looks like a little hands-on medicine is a win-win strategy where your sore, tired muscles are concerned—and this study serves up some compelling clinical evidence to prove it.

References:

1. ScienceDaily. http://www.sciencedaily.com/releases/2012/02/120201173226.htm. Accessed May 2, 2012.

2. J D Crane, et al. Science Translational Medicine. 2012;4(119):119ra13.

Female athlete triad

Wednesday, July 6th, 2011

 

Female athlete triad in Asia is not well studied although the prevalence is not that low (about 2-4%). Many of us as practitioners could easily miss the diagnosis as the presenting symptoms might be vague and thus a high degree of suspicion is needed.

There was a study in 2009 among 67 elite female athletes in Malaysia aged between 13-30 years that were subdivided into the ‘leanness’ and ‘non-leanness’ groups. {{{o}}}

The findings:

  1. Prevalence of the female athlete triad was low (1.9%) as compared to studies in Europe and the USA of about 4% , but the prevalence for individual triad component especially eating disorder was high, especially in the leanness group.
  2. The prevalence of subjects who were at risk of menstrual irregularity, poor bone quality and eating disorders were 47.6%, 13.3% and 89.2%, respectively, in the leanness group; and 14.3%, 8.3% and 89.2%, respectively, in the non-leanness group.

As eating disorder is the dominant innocuous presenting feature and precedes the other components, it is thus easy to miss the diagnosis in Malaysia due to the low prevalence of the typical triad disorders. It is therefore prudent for coach and nutritionist working with such athletes to be vigilant in seeking out any one of the components of the triad especially among those participating in sports that emphasize a lean physique as it would allow early treatment and prevent further complications.

Reference:

Ye Vian Quah; Bee Koon Poh pbkoon@gmail.com; Lai Oon Ng; Mohd Ismail Noor Ye Vian Quah; Bee Koon Poh pbkoon@gmail.com; Lai Oon Ng; Mohd Ismail Noor The female athlete triad among elite Malaysian athletes: prevalence and associated factors. Asia Pacific Journal of Clinical Nutrition 2009, Vol. 18 Issue 2, p200-208Retrieved on 21 June 2011 from http://apjcn.nhri.org.tw/server/APJCN/Volume18/vol18.2/Finished/8_1392_200-208.pdf