On the Merits of Moderation: Salt, Cholesterol, and Vitamins

At excellent overview from NY Times that explains that strict reductions in salt and cholesterol may be detrimental and that additional vitamins may be harmful. Here’s the link: Dash of Salt Does No Harm

Here’s an excerpt:

The second New England Journal of Medicine study did just that. In addition to looking at high sodium diets, it also compared the health outcomes of those who had very low sodium diets. What they found was worrisome. When compared with those who consumed 3-6 grams per day, people who consumed less than 3 grams of sodium per day had an even higher risk of death or cardiovascular incidents than those who consumed more than 7 grams per day.

This result would be shocking if we in the medical community hadn’t seen it before. But we have. In 2011, researchers published a study in the Journal of the American Medical Asssociation after following 3,681 people over almost a decade. They, too, found that excessive salt intake was associated with high blood pressure. They also found that a low-sodium diet was associated with higher mortality from cardiovascular causes….

Why experts and organizations feel the need to go from one extreme to the other is unclear. But it’s unfortunately something we do far too often in medicine.

Take cholesterol. Initially, people believed that the evidence was pretty compelling that high cholesterol was bad for you…Eggs were shunned. But later research showed us that egg consumption had no relationship to cardiovascular disease for most people. In fact, a majority of people’s serum cholesterol level has little to do with how much cholesterol is in their diet. Today we use medications to lower our cholesterol levels. Once again, though, our sights keep shifting lower…

We have to learn that when one extreme is detrimental, it doesn’t mean the opposite is our safest course.

Micronutrient Monitoring in Intestinal Failure

J Pediatr 2013; 163: 1692-6.  This retrospective study of prospectively collected data from 178 children provides data with regard to micronutrient deficiency among intestinal failure patients transitioning to enteral feeds. Figures 1 and 2 along with Table 2 provide the prevalence of micronutrient deficiency while receiving supplemental parenteral nutrition (PN) and while on full enteral nutrition (FEN).  Iron deficiency was most common in both situations with prevalence of 84% and 61% respectively. With the exception of folate (0%), all of the vitamins and micronutrients had fairly high rates of deficiency.  While on FEN,  deficiencies were  the following:

  • Vitamin A        19%
  • Vitamin B12    6.5%
  • Vitamin D        30%
  • Vitamin E          6%
  • Copper            8%
  • Iron                61%
  • Selenium         4%
  • Zinc               23%

The study does not indicate that the deficiency values were adjusted based on CRP values.  Instead, “low serum levels were used to define deficiencies.”  This is likely to lead to numerous errors.  Nevertheless, it is clear that these deficiencies are common.  Another finding of the study was that normal anthropometrics did not reduce the frequency of these deficiencies.  In their patient population, 57 of 136 (42%) with sufficient height and weight data had a height-for-age z-scores of <-2 by the time of FEN; where as 52 of 139 patients (37%) had weight-for-age z-scores of <-2.

A recent post on The Pediatric Nutritionist blog provides a suggested approach to the monitoring of vitamins and micronutrients based on the need for parenteral nutrition and on the need to consider inflammatory markers in the interpretation of these lab values: The Importance of Nutrition Lab Monitoring Protocols Featuring 

Bottomline: Vitamin and micronutrient deficiencies are common among intestinal failure patients.  In addition, a large percentage of these kids are not large at all.

Related blog post:

What happens to micronutrient levels in the hospital setting 

What helps kids poop?

While there are a number of answers to the above title, the answer that I’m looking for is physical activity (JPGN 2013; 57: 768-74).

With regard to the referenced study, a large prospective birth-cohort study (n=347 participants) in Rotterdam showed that preschool children with increased physical activity had about 1/3rd less frequency of functional constipation in the fourth year of life.  Activity measurements at the age of 2 years were accomplished by wearing ActiGraph accelerometers during 1 weekday and 1 weekend day.  Additionally, children who had physical activity of 60 min/day at age 4 had about 1/2 the likelihood of having functional constipation.  There are several limitations to the study; reduced activity and constipation could both be present in some individuals as a consequence of personality or psychologic attributes rather than physical activity having a causal relationship in causing constipation.

Bottomline: Another good reason to encourage physical activity –it might help with regular bowel habits.

Also, on a separate note, a recent blog post by Kipp Ellsworth is a useful reference for lab monitoring (micronutrients and vitamins) in children with short bowel syndrome:

Blog | The Pediatric Nutritionist | Covering the world of infant, child 

Related blog entries:


Vitamins: often ‘throwing money down the drain’

From USA Today: Medical journal: ‘Case closed’ against vitamin pills

“it’s time for most consumers to stop wasting money on multivitamins and other supplements, because they have no proven benefits and some possible harms.”

That declaration comes in a strongly worded editorial that accompanies two new studies and an expert panel’s report published Monday in the Annals of Internal Medicine.

“The message is simple: Most supplements do not prevent chronic disease or death, their use is not justified, and they should be avoided,” says the editorial, signed by two researchers from Johns Hopkins University in Baltimore, one British researcher and one of the journal’s senior editors…

The new results from that study will disappoint anyone who hoped a multivitamin might keep them sharp in old age. The study followed male physicians over age 65 for an average of 11 years and found multivitamins had no effect on cognitive decline…

A second, unrelated, new study in Annals found high-dose multivitamins had no effect on the progression of heart disease in heart attack survivors…

there are exceptions. For example, health officials strongly urge women of childbearing age to take folic acid, to prevent birth defects. Some ongoing studies of vitamin D, he says, are justified because some benefits…

most of the 53% of U.S. consumers who use supplements are wasting money, to the tune of $28 billion a year.

Same story from NY Times: http://t.co/kEwrk1mGyQ

Related blog entry:  Live longer -don’t take your vitamins? | gutsandgrowth