Highlight HEALTH

• One Hand Clapping | Science-based Medicine

  Mark Crislip ponders the meaning of “better” and explores objective and subjective therapeutic responses. A must read!

• Trusted doesn’t mean accurate. Safe is almost certainly stale. | e-patients

  How do you know if you can trust medical information from a website? Did you know the guidelines used to determine "trusted" websites were all conceived between 1995 and 1999, when information available was entirely static (think pre-Health 2.0).

• Does your diet determine what sex your baby will be? | Doctor David’s Blog

  Dr. David discusses an Oxford study suggesting that sex determination may be more complicated than sperm with an X or Y chromosome.

• My take: Just say no to unnecessary tests | Kevin, M.D.

  Kevin believes that excessive testing, combined with demand for the latest diagnostic modalities, play a pivotal role in increasing healthcare costs and suggests we say no to unnecessary tests.

• Healthy, frugal eating | Wise Bread

  Wise Bread describes how to eat and suggests we recreate a tradition of healthy, frugal eating.

Approximately eight million Americans search for health information online every day [1]. However, the information those health seekers are reading may not be very healthy at all. A new study by the Center for Medicine in the Public Interest recently reported that the information prominently displayed in search engine results was not only misleading and confusing, but dangerous for patients [2]. Case in point: using two safe and effective prescription medications (Crestor and Avandia) as an example, nearly 65% of the first three pages of Google search results came from sites that were biased or contained unverified information. Add to this the fact that most search engine users click on a result within the first three pages of search results [3] and people searching for health information online are likely to be viewing websites that aren’t credible or trustworthy.

At Highlight HEALTH 2.0, guest writer Matthew Krajewski focuses on the importance of information categorization and online health search. In his article Health Web 1.0, 2.0 and 3.0, Matthew discusses health search in the context of internet technology trends. His article echoes the difficulty with search engines today:

Standard search results will require a user to determine for themselves what is a trustworthy source and what is plain spam. RightHealth treats the categorization of health information much like how an editorial health site would treat their articles: insuring results are relevant, trustworthy and of value to the end user.

I wrote about The Trust and Credibility of Healthcare Blogs last year and discussed the Health On the Net (HON) Foundation, a non-profit organization that is attempting to guide the growing community of healthcare providers and consumers on the World Wide Web to sound, reliable medical information and expertise through quality assessment and systematic and stringent peer review. Both Highlight HEALTH and the Highlight HEALTH Web Directory are HONcode accredited.

When searching for health information online, be sure to look for credibility seals, such as accreditation from HON or URAC. Make sure the health information you find is dated and cites references. Ask yourself, does the website link to other sources of credible information? Remember that health information found online is only valuable when that information is correct.

Additional health search resources can be found in theHighlight HEALTH Web Directory.

References

1. Fox S. Online Health Search 2006: Most internet users start at a search engine when looking for health information online. Very few check the source and date of the information they find. Washington (DC): Pew Internet and American Life Project. 2006 Oct 29.
2. Goldberg et al. Insta-Americans: The Empowered (and Imperiled) Health Care Consumer in the Age of Internet Medicine. The Center for Medicine in the Public Interest. 2008 Jan.
3. iProspect Search Engine User Behavior Study. iProspect. 2006 Apr.

After feasting on your Thanksgiving dinner today, a specific word may come to mind: tryptophan. Tryptophan is an amino acid found in high levels in turkey. The main reason for the association between tryptophan and drowsiness is that tryptophan is a chemical precursor to melatonin, a neurotransmitter that plays a role in regulating the circadian cycle, the regular changes in mental and physical characteristics that occur over the course of 24 hours. Indeed, purified tryptophan is a mild sleep-inducing agent [1].

Tryptophan breaks down into at least three metabolites. The first is melatonin, which can lead to sleepiness. The second is niacin, a form of vitamin B. Tryptophan also breaks down into serotonin, a neurotransmitter that regulates agression, body temperature, appetite and mood. In a recent study presented at the Society for Neurosciences, Robert Rodgers, Ph.D. and his colleagues at Oxford University used game theory to study serotonin’s role in social interactions [2].

The study asked volunteers to play a two-person game called Prisoner’s Dilemma. In the game, people make choices that affect each other, either choosing to make a move that wins them money from the other player or a move that wins both players money. Under normal circumstances, players were found to cooperate about 75% of the time. However, by depleting levels of l-tryptophan, which in turn reduced levels of serotonin, researchers found a significantly decreased level of cooperation among players. The lowered levels of serotonin also effected players judgment of the social characteristics of others and they rated fellow players as less trustworthy.

According to Rogers, serotonin may [2]:

… play a role in modulating the cognitions that underpin dependable relationships with our social partners.

The research findings suggest that serotonin deficiency may impair continual cooperation and diminish the reward value of cooperative behavior.

Does all this mean we’re more trusting after a Thanksgiving day meal? Likely not. Scientists haven’t yet determined how increased levels of tryptophan affect trust. However, after a large meal of turkey, stuffing, gravy, cranberries, sweet potatoes and pumpkin pie, brain levels of tryptophan may actually decrease.

The transport system that’s used to take tryptophan to the brain is shared by a number of other amino acids and there’s competition between them. Thus, after a large meal, less tryptophan will reach the brain than on an empty stomach. In addition, this means that, contrary to popular belief, the tryptophan in turkey does not cause drowsiness.

So why are we so sleepy after a Thanksgiving meal?

It’s not unusual to feel sleepy after eating a lot, especially after consuming large amounts of high-carbohydrate foods. Indeed, consumption of high glycemic index foods has been shown to decrease the time it takes to fall asleep [3]. Additionally, it’s not unusual to feel sedated after a high-calorie meal. The best way to reduce drowsiness this Thanksgiving? Simple … eat less.

Resources

1. Hartmann et al. L-Tryptophane and sleep. Psychopharmacologia. 1971;19(2):114-27.
   View abstract
2. Research reveals brain areas for types of decision-making, shows how a brain chemical underpins social interaction. Society for Neuroscience. 2007 Nov 4.
3. Afaghi et al. High-glycemic-index carbohydrate meals shorten sleep onset. Am J Clin Nutr. 2007 Feb;85(2):426-30.
   View abstract