It is a quintessentially American tradition: gathering with family and friends to feast -- to the point of excess -- and reflect on all for which we can be thankful. And just as much a part of the day as turkey, parades, and football, is the post-meal nap. What is it about the Thanksgiving feast that makes us so sleepy?

The most often-cited culprit is an amino acid, or building block of protein, called tryptophan. This is found in turkey, but it is found in higher concentrations in other foods, including: egg white, cod, soybeans, parmesan and cheddar cheese, pork chops, and (for the adventurous) caribou. One hardly hears of anyone complaining of excessive sleepiness after eating these foods. So what is to blame?

It may be the other things we pile onto our plates and into our goblets. Alcohol certainly can make us sleepy, but it's not the only culprit. It has been demonstrated that meals rich in carbohydrates -- such as potatoes, yams, breads, and countless other Thanksgiving foods -- trigger insulin release. This promotes the uptake by muscle of amino acids other than tryptophan. Lonely and unused trytophan builds up in the blood and is shuttled across the blood-brain barrier where it is converted into a neurotransmitter, or brain chemical, called serotonin. The serotonin is further metabolized into melatonin, which is a hormone with sleep-promoting qualities.

When one is facing the desperation of another sleepless night, it may be natural to wonder if treating insomnia is possible with the use of aromatherapy.

The human brain is an extraordinary thing, and it is not uncommon for us to strongly link memories with our senses, including smells. For example, a whiff of a familiar perfume may bring your grandmother promptly to mind. Any number of other scents may cause memories and feelings to envelop you. Are there certain scents that can likewise induce sleep?

Find out more.

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In a recent study by the Centers for Disease Control (CDC), one in nine adults reported never getting enough sleep during the previous month.

Some 11 percent said there was not one single day during the previous month that they were able to get enough sleep. Most adults need seven to nine hours of sleep each night. However, it is possible to determine your sleep needs. Another 16.8 percent said they had gotten insufficient sleep for more than half of the month.

The data were collected as part of the CDC's Behavioral Risk Factor Surveillance System, which surveyed 404,000 people in all 50 states via telephone. Experts agree that insufficient sleep can have major health consequences.

_{Source: McKnight-Eily L., et al. "Perceived insufficient rest or sleep among adults - United States, 2008". MMWR 2009; 58: 1175-79.}

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As the year draws to a close, it may be time to use up that money you set aside in your flexible spending account before it's too late.

Flexible spending accounts are an option provided by employers for setting aside pre-taxed income that can be used for anticipated health expenses. These expenses can be quite varied, and may include office copayments, medications, or equipment used to treat sleep disorders. Unfortunately, any money that is not used by the end of the year is lost.

So if you have money sitting in your flexible spending account waiting to be used, now is the time to act.

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