Are the New Recommendations on Vitamin D a Missed Opportunity?

The new report released today by the Institute of Medicine on recommended vitamin D intake is a bit like getting that shirt you wanted for your birthday, but it turned out to be the wrong color and the wrong size (report).  It’s sort of what you wanted but not really.

While the new report kicks up recommended intake of vitamin D to 600 IU daily for adults up to age 70 and 800 IU daily for those over 70, these amounts fall short of the levels shown in research studies that could have benefit for conditions such as heart disease and cancer^{1, 2, 4}.  Looking at colon cancer alone, studies have found that high levels of vitamin D could cut the risk of the disease in half compared to low levels⁴ (previous post).

And it's estimated that over half of all women, and over 40 percent of all men, in the United States have less than optimal blood levels of vitamin D, often suggested to be 75 nmol/dL of a type of circulating vitamin D called 25(OH)D ^{5, 6} .  Those prone to very low sun exposure or low vitamin D levels are even worse off:  the elderly, the very overweight, people with dark skin, and those who largely live in northern areas (where vitamin D-producing UV-B sunlight can be low for much of the year).

To reach beneficial blood levels of vitamin D, most people would need to take about 1000 IU per day, with those prone to lower levels taking perhaps 1500 IU per day.  This is well above the new guidelines of 600 per day for most adults.

The IOM report takes a typically conservative approach to assessing studies of potential benefits and potential risks related to vitamin D intake, as well as to the blood levels of vitamin D that qualify as “sufficient.” Such an approach often minimizes potential benefits while highlighting potential risks.  This can help safeguard the nation’s health from the zeitgeist of diet crazes, but when it comes to vitamin D it seems more like a missed opportunity. 

Related CNiC Posts

Vitamin D

Related Web Resources

Harvard's Nutrition Source

References Cited

1. Heaney RP. Vitamin D in health and disease. Clin J Am Soc Nephrol 2008;3:1535-41.
2. Melamed ML, Michos ED, Post W, Astor B. 25-hydroxyvitamin D levels and the risk of mortality in the general population. Arch Intern Med 2008;168:1629-37.
3. Institute of Medicine. Dietary Reference Intakes for Calcium, Phosphorus, Magnesium, Vitamin D, and Fluoride. In; 1997.
4. Bischoff-Ferrari H. Health effects of vitamin D. Dermatol Ther 2010;23:23-30.
5. Zadshir A, Tareen N, Pan D, Norris K, Martins D. The prevalence of hypovitaminosis D among US adults: data from the NHANES III. Ethn Dis 2005;15:S5-97-101.
6. Dietary Supplement Fact Sheet: Vitamin D. 2008. (Accessed 2008, at http://ods.od.nih.gov/factsheets/vitamind.asp.)

Passive smoke exposure kills

New data on the global burden of disease caused by exposure to second hand smoke (see report) adds to the urgency for action to prevent cancer heart disease asthma and other conditions caused by this exposure (Oberg M, Jaakkola MS et al. 2010). As noted in media coverage of the new findings, worldwide exposure to second had smoke is substantial – approximately 40 percent of children are exposed. Together, this exposure in children and adults caused 379,000 deaths from heart disease, 165,000 from lower respiratory infections, 36,900 from asthma and 21,400 from lung cancer.

Exceptionally strong evidence shows that reducing exposure to second hand smoke reduces the risk of acute myocardial infarction (Lightwood and Glantz 2009; Meyers, Neuberger et al. 2009; Mackay, Irfan et al. 2010). Strong data from Scotland shows a marked decline in hospitalizations due to asthma among children following the passage of smoke free legislation in 2006, which banned smoking in public places (Mackay, Haw et al. 2010).

It is time we followed the evidence and implemented policies that support public health throughout the world. Implementing the US tobacco control strategy  would be a useful first step locally. International efforts must also address the large and preventable cause of premature morbidity and mortality.

Literature cited

Lightwood, J. M. and S. A. Glantz (2009). "Declines in acute myocardial infarction after smoke-free laws and individual risk attributable to secondhand smoke." Circulation 120(14): 1373-1379.

Mackay, D., S. Haw, et al. (2010). "Smoke-free legislation and hospitalizations for childhood asthma." N Engl J Med 363(12): 1139-1145.

Mackay, D. F., M. O. Irfan, et al. (2010). "Meta-analysis of the effect of comprehensive smoke-free legislation on acute coronary events." Heart 96(19): 1525-1530.

Meyers, D. G., J. S. Neuberger, et al. (2009). "Cardiovascular effect of bans on smoking in public places: a systematic review and meta-analysis." J Am Coll Cardiol 54(14): 1249-1255.

Oberg M, Jaakkola MS, et al. (2010). "Worldwide burden of disease from exposure to second hand smoke: a retrospective analysis of data from 192 countries." lancet on line Nov 26.

The Long Haul: New Study Suggests Specific Protein & Carbs Combo May Help Keep Weight Off

As anyone who's ever been on a diet knows: taking the pounds off can be hard, but keeping the pounds off can be even harder.  The main reason for this simply seems to be that it's just easier to keep up with a new exercise and diet program over the short term than it is over the long-term.  While we may be willing to sustain ourselves on some wild, restrictive diet for a few months, especially if the pounds start to melt away, over time it gets harder and harder to keep it up, and eventually our old habits, our old ways of doing things, slowly bubble back to the surface, and we find ourselves putting the weight back on.

This is why most experts suggest making a small number of small changes when it comes to weight loss.  Taking baby steps gives us time to get our footing with a new behavior, with a new approach to eating, and helps it to actually become part of our lifestyle rather than a strange restriction that needs to be endured and then eventually discarded after three months because its so unpleasant.

In this vein of small changes breeding long term success is a Danish study in the latest issue of the New England Journal of Medicine that shows that small differences in the make-up of what eat can help maintain real weight loss over time.

In this study, about 800 overweight participants who had recently lost weight were randomly assigned to one of five diet groups - each group had a varied combination of protein level and glycemic load, a measure of how quickly the carbohydrates in the diet are converted to glucose in the blood (study).  Diets with high glycemic loads (such as those with a lot of white bread, potatoes, and white rice) have been shown in some studies to increase the risk of weight gain as well as heart disease and diabetes.  Diets with a low glycemic load (such as those with a lot of whole grains or low amount of carbohydrates) may help keep calorie intake in check and promote feelings of fullness.

The researchers found that the group who ate a high protein, low glycemic load diet had the most success keeping weight off over time.  Those who ate a low protein, high glycemic load diet did the worst.  Worth noting: those who ate the high protein, low glycemic load diet not only had the most weight loss success but also had the highest rate of adherence of any group, meaning more people in this group were more likely to keep up with that way of eating than in any other group.

While the weight benefits were pretty modest, with participants in the high protein, low glycemic group weighing an average of about 4.5 pounds less over six months than those in the low protein, high glycemic group, it is a real difference that if sustained over time could have a big impact on health, both for the person, and on a broader scale, the nation.

Although this is just a single study, what's most heartening from these results is that maintaining the new weight after weight loss, and even continuing to lose weight, seems possible over the long term with a diet that isn't that radical and that's enjoyable enough to continue over the long term.

A healthy high protein diet with a low glycemic load would include foods like skinless chicken, fish, beans, low fat dairy as well as whole grains and brown/wild rice.  Healthy fats, like canola oil and olive oil, also help keep glycemic load down because they slow down digestion.  Red meat, high-fat dairy, and refined grains should always be kept to a minimum.

Related CNiC Posts:
Weight
Diet
Exercise

Even small breaks are good

A study out this month in the journal Cancer, Epidemiology, Biomarkers & Prevention reviewed the literature on sedentary behavior and cancer. Ten of the 18 studies included in the review found a significant positive association between sedentary behavior and cancer risk - specifically cancers of the colorectum, endometrium, ovaries and prostate. Sedentary behavior isn't just a lack of physical activity - it is prolonged sitting or reclining. Someone can meet the physical activity guidelines of 30 minutes of moderate intensity physical activity each day (e.g., a brisk 30 minute walk) and still be quite sedentary if s/he spends the rest of the day sitting.

This is why more and more public health advocates are touting the value of lifestyle activity - the movement associated with daily living. And some, like Dr. Toni Yancey, are taking it a step further and advocating we build purposeful movement focused breaks into our workplaces. In today's Personal Health column, Jane Brody highlights Dr. Yancey's efforts and her new book "Instant Recess". In her book, Dr. Yancey suggests building two 10-minute breaks of a fun group activity into the work day. These kind of programs have proven successful in the business world at improving the health of employees and at improving productivity. Similar programs in schools have been shown to improve learning.

The value of these recess/activity breaks at reducing cancer risk has yet to be shown, but with so many other positive outcomes - most notably feeling better, they seem like a great idea and one CNiC can definitely get behind!

Quitting smoking vs CT scans: cost, risks and benefits

There is lots of talk in the news right now about scanning - mostly about the kind in airports and whether it is too great an invasion of privacy. But medical scanning has also been making headlines - specifically, whether we do too much of it unnecessarily, as CT and X-ray scans expose the body to radiation, which has risks. Recent reports indicated that CT scans of smokers may reduce their risk of mortality by 20%, which may suggest the exposure to radiation is worth the risk. However, as Laura Gottleib points out in the San Francisco Chronicle, prevention is a cheaper and lower risk option. 87% of lung cancer is caused by smoking and CT scans aren't going to eliminate that - they are simply going to help us catch and treat the lung cancer earlier. Preventing people from starting smoking, minimizing (or eliminating) exposure to secondhand smoke and helping people quit prevent lung cancer from developing.

What about the cost? According to Gottleib, the cost of scanning all former and current smokers in the United States is roughly $30 billion per year. In contrast, California's Tobacco Control Program decreased adult tobacco use by 35 percent, saving $86 billion in health care costs. How does she get at that HUGE savings? For every $1 California spends, it reduces statewide health care costs by $3.60, according to research done by Tobacco Free Kids.

Advances in early detection and treatment are great, but let's not forget the value of prevention!

Read more: http://www.sfgate.com/cgi-bin/article.cgi?f=/c/a/2010/11/21/EDKC1GEUHP.DTL#ixzz161rYIMli

Lost in a Food Desert? Where Do You Buy Your Veggies?

This morning, I had the extreme pleasure of hearing Dr. Bill Dietz of the CDC's Division of Nutrition and Physical Activity in the Center for Chronic Disease Prevention and Health Promotion speak about Policy and Environmental Changes to Prevent and Control Obesity at the Washington University School of Medicine Grand Rounds. Dr. Dietz touched on many topics, but one that stood out to me was the focus CDC has on its list of priority strategies to address important health behaviors: increasing access to fruits and vegetables through retail stores.

I'm sure many of my fellow news junkies saw the NY Times Magazine story about Walgreens' new program to eliminate food deserts. A food desert the NY Times describes as "urban neighborhoods where there are few grocers selling fresh produce, but a cornucopia of fast-food places and convenience stores selling salty snacks (though, strictly speaking, the term can be applied to rural or suburban areas, too). Often the problem afflicts low-income areas abandoned or shunned by food businesses that focus on better-off consumers"

Food deserts are a problem that numerous non-profit and community groups have worked to tackle. Most notable is probably the Food Trust based in Pennsylvania. The Food Trust work has expanded to other states and has had some notable successes in encouraging supermarket development and expanded farmers' market programs. Perhaps it shouldn't be surprising then that when the US government announced the $400+ million Healthy Food Financing Initiative to bring grocery stores to underserved communities, it did so in Philadelphia.

Do big intiatives like this work? The general consensus is cautious optimism. Certainly having the White House behind programs like this is a big deal. But, as Marion Nestle noted, voluntary programs such as these don't always move us very far in the path to healthier communities. That businesses are seeing an opportunity here, perhaps points to some real movement (even if the cynic in me points out that this is about the bottom line for any business). I'm looking forward to seeing Walgreens provide some data on the successes (or not) of their program, something the Times article notes it has been unwilling to do so far. I'm also curious to see more data on whether these programs change fruit and vegetable intake, and ultimately rates of associated comorbidities, like obesity. Economic disparities have a big effect on food choices and the economic challenges facing families will be a big driver of our success in food access and numerous other health challenges.

Cancer books - do you read them?

I've been pretty reluctant to pick up best seller books about cancer and the history of cancer since I bought one a few years ago that I found so terrible I finally decided my time was being terribly misspent. So this morning's Morning Edition interview with Siddhartha Mukherjee, the author of The Emperor of All Maladies: A Biography of Cancer was intriguing to me. The NY Times Book Review gave it a positive endorsement as well. Dr. Mukherjee had a great perspective on how we're doing in the "War on Cancer" and at the end of the interview, I decided to add his book to my Kindle.

Do you read books of this kind? Or do you find they don't add much to your knowledge base? How do you choose which ones to read given the boom in "health" books?