January 8, 2013
Could Diet Soda Cause Clinical Depression?
A new study suggests a link between diet soda and depression, but it’s important to remember the difference between causation and correlation. Image via Flickr user DavidMartynHunt
Despite a lack of evidence in the scientific literature, we’ve seen aspartame—the calorie-free sugar sweetener found in diet drinks—blamed for a variety of health problems, everything from multiple sclerosis to migraine headaches. But here’s a new one: clinical depression?
In a preliminary release of a study to be published by Honglei Chen and colleagues from the National Institutes of Health, a survey of 263,925 adults nationwide indicated that consumption of sweetened drinks—especially diet sodas—was associated with an increased chance of a depression diagnosis. The authors, who will present their work at the American Academy of Neurology’s annual meeting in March, released only a summary of their study today.
To come to the findings, the researchers combined old data with new. They began by examining a survey originally conducted in 1995 and 1996 in which adults between the ages of 50 and 71 recorded their daily soda, tea, fruit punch and coffee consumption. Then, for this study, they returned to the same survey participants more than a decade later and asked if they had been diagnosed with depression in the years since 2000.
They found that those who drank four or more cans of sweetened drinks (whether soda, diet soda or fruit punch) had a significantly higher chance of being among the 11,311 study participants who were later diagnosed with clinical depression that those who didn’t. For sodas as a whole, there was a 30 percent greater chance of depression, but diet sodas carried a further 22 percent increase as compared to regular ones. Interestingly, regular coffee consumption was associated with a 10 percent lower chance of depression.
Does this mean you should stop drinking diet Coke and starting chugging coffee immediately? Probably not. This type of suggested link between two seemingly unrelated factors is an ideal time to bring up the difference between causation and correlation. Do the ingredients in both diet sodas and normally-sweetened drinks trigger changes in brain chemistry that lead to depression? Or are people with the tendency to become depressed simply more likely to drink these beverages in the first place?
Without the full paper, it’s hard to know for sure—we don’t know if the study’s authors controlled for all relevant factors, making sure to compare study participants who were alike in all ways except for their beverage consumption. As a result, a third, unrelated factor may cause people to both drink more soda and become depressed more frequently. Since the study is backward-looking, it’s especially hard to rule this out: The researchers can’t go back to 1996 and make sure to ask the participants every potentially relevant question to ensure that all potentially important factors have been taken into consideration.
Additionally, the fact that an association was found for both regular and diet sodas makes a causative link seem less likely. For that to be the case, either both sugar and aspartame must trigger depression, but at different frequencies, or a third ingredient in both sodas is responsible, but is somehow modulated by the presence of the natural or artificial sweetener.
So, what’s the simplest explanation? Those who like to drink a lot of diet soda are more likely to already be at risk of developing depression. And people who like to drink a lot of coffee are already less likely to be among this group. Perhaps, then, your underlying preference for how you get your energy buzz—whether through coffee or sweet drinks—may reflect something about your mental state.
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Correlation vs causation:
http://xkcd.com/552/
Because of the depletion of serotonin aspartame triggers all kinds of psychiatric and behavioral problems and interacts with “all” antidepressants. It triggers big time bipolar, anxiety, schizophrenia, paranoia, suicidal tendencies, insomnia, panic attacks, etc.
Here is a report on it from psychiatrist Ralph Walton, M.D. who also did a study on aspartame: http://rense.com/general78/psych.htm Dr. Walton has been exposing aspartame and psychiatric problems for decades. You can contact me for his email from my web site, http://www.mpwhi.com Dr. Betty Martini, D.Hum, Founder, Mission Possible Intl
It amazes me that journalists today will write something and not refer the the existing facts. Aspartame science has been around for decades. Most of the real data has been suppessed by the FDA. Currently 92 adverse health conditions are allowed by the FDA, but there are many more they ignore. If you do due diligence you can in fact find the science. And there certainly is no lack of it.
aspartame in 1 litre diet drink gives 60 mg methanol, same as from 1
pack cigarettes, causing MS, as ADH1 enzyme makes methanol into
formaldehyde inside cells of inner walls of blood vessels at base of
brain, the perivascular loci of MS and Alzheimer’s — pivotal WC Monte
paradigm: Rich Murray 2012.12.31
http://rmforall.blogspot.com/2012/12/aspartame-in-1-litre-diet-drink-gives.html
Here are updated facts about methanol toxicity in humans, published by
Prof. Woodrow C. Monte, Food Science and Nutrition, Arizona State
University, retired 2004, who published a seminal review in 1984:
Due to an impaired catalase enzyme inside the hundreds of peroxisomes
in each cell, which are unable to safely process methanol, humans are
ten to hundred times more vulnerable than any animal to
methanol-formaldehyde toxicity.
Contrary to decades of disinformation by some industry funded
scientists, methanol is not mostly processed in the liver into
formaldehyde and then quickly into formic acid, portrayed falsely as a
strong toxin for the whole body — in fact formic acid is so safe that
WC Monte used it for salad dressing for lunches in his lab. Methanol
actually circulates in the blood to all parts of the body, including
the brain and the fetus, with a half-life of about 2.5 hours, dropping
5 halves every 12 hours to 3% of its initial level, while ethanol
drops by half every 20 minutes, 36 halves in 12 hours. Two labs have
shown that when people drink at night, they get painful hangovers in
the morning, when the ethanol is all gone, as then the tiny amount of
methanol starts being made into formaldehyde by ADH1 in the brain.
[ 1987, 1998 AW Jones, 1995 YS Woo ]
The only places in the brain that have high levels of ADH1 enzyme are
the inner walls of the blood vessels at the base of the brain, within
the thin blood-brain barrier layer, so the formaldehyde diffuses out
slowly to harm brain tissue, creating the first “perivascular” lesions
of multiple sclerosis and Alzheimer’s — the incidence of these
diseases has skyrocketed since fall 1983, when Donald Rumsfeld started
mass marketing aspartame (E951), the largest methanol source.
The WC Monte January 2012 text is available at Amazon.com, “While
Science Sleeps”, low cost ebook, backed by his online archive of 745
free full text medical research references at WhileScienceSleeps.com ,
while two full chapters are free: Chapter 9, “Multiple Sclerosis” and
12, “Autism and Other Birth Defects.”
I hope this information is helpful.
The large percentages of depression in the people followed is enough to get my attention. I have increased my diet cola intake a lot the past ten years, especially lately, and have been very depressed now for the first time ever. Not feeling better was becoming a concern. Now the diet stuff can go before I try medication that may not even be needed.
The 22% increase in depression diagnoses in people who drank Diet Coke (vs. regular Coke) would be very hard to pin on one ingredient (such as aspartame); it is probably just reflective of the mental state of the people who drink it, as you point out. I think it would be fair to say that many (not all) people who choose diet drinks over regular may be more concerned with their weight, body image, etc. than those who choose a regular sweetened drink. Being unhappy with their body or struggling to obtain an ‘ideal’ body image may contribute to low self-esteem and depression. This is oversimplifying a small part of a complex issue, but it could certainly account for some of the additional 22%.