Serotonin and Carbohydrates
The Placebo Effect
In the not so distant past, doctors sometimes prescribed what they considered inert substances to patients when there was no real medicine to cure their ills -- or when they believed that a patient was a hypochondriac. They called these pretend medicines "placebos" from the the Latin meaning "I will please." An oft used placebo was a sugar pill. After prescribing this placebo, doctors were surprised to find that patients did actually feel better. This is known as the "placebo effect", and it still confounds results in clinical trials, where some of the subjects are given a "real medication" and some are given a placebo. Many consider the placebo effect to be purely psychological.
However, no substance is completely without physical effect, least of all the sugar found in many placebos. Taking sugar does have an effect on our mood. It is not just a psychological phenomenon. There are chemical reasons for how this works.
Dietary Carobohydrates and Mood
- Carbs are essential for effective dieting and good mood, Wurtman says - MIT News Office
Judith Wurtman and colleagues have found that when you stop eating carbohydrates, your brain stops regulating serotonin, a chemical that elevates mood and suppresses appetite.
Serotonin and insulin
Here is how ingesting sugar -- or some carbohydrate that is broken down into sugar after digestion -- can alter our mood for the better. When we digest carbohydrates, our blood sugar levels rise, and then insulin is secreted, lowering the blood levels of most amino acids with the exception of tryptophan, which is a precursor to serotonin. When there is more tryptophan than other amino acids, it enters the brain at a higher rate. The brain then produces more serotonin. (See the GO ASk ALICE link provided.)
Serotinin is a substance found both in our brains and in our gastrointestinal tract. Serotonin has many functions. In the brain, it acts as neurotransmitter, and it helps to regulate mood.
Antidepressants are also called serotonin re-uptake inhibitors, preventing the supply of serotonin in the brain from going down. However, antidepressants are not the only way to elevate serotonin levels. Many ordinary people self-medicate when they are feeling depressed by eating lots of carbohydrates. We don't need a doctor to prescribe us a placebo. We crave carbs when we are feeling down, and eating carbs can be an effective means of elevating our mood. The problem is that the effect only lasts for a little while, and then the patient comes crashing down, in need of an even higher dose of carbs.
Go Ask Alice on Carbs and Serotonin
- Go Ask Alice!: Serotonin and foods?
(1) Alice, Are there any foods that can put serotonin into my system, or does there have to be some type of chemical ingestion in order for it to work? Thanks a bunch!
MIT STUDY -- high carb supplement for those on antidepressants
- MIT researchers: high-carb supplement helps with weight loss - MIT News Office
MIT researchers reported recently in the Psychopharmacology Bulletin that a high-carbohydrate dietary supplement can help patients who experience weight gain while taking antidepressants.
Bipolar Disorder and Carobohydrate Consumption
In bipolar disorder, which was once called manic-depression, patients suffer from periods of depression followed in close succession by periods of high energy and euphoria known as manic episodes. A manic-depressive who self-medicates using the consumption of carbohydrates is very likely to trigger a manic episode.
The sugar-insulin-tryptophan-serotonin cycle is currently under scrutiny for a number of reasons. Because people who have high levels of serotonin don't feel hungry, some researchers are looking into uses of serotonin as an appetite suppressant. Others have suggested that low carb diets are to be avoided by those who have a predisposition to clinical depression, since serotonin levels are not stimulated by non-carbohydrates, and this is the reason a diet high in fat is seen as de-energizing. This is especially a problem for some people on anti-depressants, and paradoxically, they tend to gain weight.
However, stimulating the production of seratonin through sugar spikes followed by insulin has the effect of pushing the individual into a cycle that is likely to spiral out of control and will ultimately lead to diabetes and weight gain.
On the other hand, since the low carb/high fat diet leads to weight loss and reduced carbohydrate cravings, serotonin levels tend to stabilize, allowing the individual to avoid excessive highs and lows. People on a low carb diet may be less energized immediately after a meal, but they maintain high energy levels throughout the day. For those suffering from bipolar disorder, it is not the exact level of serotonin in the brain that is most significant. Having a stable supply of serotonin with no peaks or valleys is very important.
For this reason, it might be better to avoid the highs and lows of the carbohydrate consumption cycle. A low carb, high fat diet can help people keep a steady keel, with fewer mood swings.
(c) 2008 Aya Katz