Researchers Link Alcoholism and Binge Eating Behavior

Addiction and the role of genetic overlap.

More evidence has arrived, courtesy of Washington University School of Medicine in St. Louis, demonstrating a genetic link between alcoholism and binge eating disorders.

In clinical practice, it is no secret that certain binge eaters and people with bulimia also show high rates of alcoholism. Various reasons have been suggested, but one of the obvious ones is that people prone to alcoholism are also genetically susceptible to certain kinds of eating disorders. A common set of genetic factors may convey these intertwined vulnerabilities to a subset of the population.

In order to examine the matter, Dr. Melissa Munn-Chernoff and coworkers followed the time-honored route: They studied twins, both identical and fraternal, from a database of 6,000 adult twins in Australia. Twin studies have been crucial to medical understanding of comorbid disorders and addiction. In general, while alcoholism and binge/purge disorders were seen as most likely genetic in origin, it was thought that the two disorders were transmitted in families independently. Writing in the Journal of Studies on Alcohol and Drugs, the researchers conclude that “in women, some of the genetic risk factors that influenced vulnerability to alcohol dependence also influenced vulnerability to both binge eating and compensatory behaviors [purging, laxatives, diuretics].”

Previous studies cited by the researchers have pegged the individual heritabilities of alcohol dependence (50-64 percent) and bulimia (28-83%). However, the question of genetic overlap had remained relatively underexplored. Munn-Chernoff and colleagues wanted to evaluate the links between alcohol dependence and binge eating behaviors in women. Among the study group, 6 percent of women had been dependent on alcohol at some point in their lives. As for binge eating, 13% of women had experienced problems with it. 14% of women had engaged in purging or laxative abuse.

The researchers judged the genetic correlation between the two disorders to be statistically relevant: “In women, the multivariate twin model suggested that additive genetic and nonshared environmental effects influenced alcohol dependence, binge eating, and compensatory behaviors, with heritability estimates ranging from 38% to 53%.”(For the specific statistical correlations, see the full-text article. The correlation was stronger for women than for men).

In addition, the study did not find any significant shared environmental influences contributing to covariance between alcoholism and binge behaviors.

Limitations of the study include an older age cohort (mean age 44 in women), higher alcoholism rates in the Australian sample compared with the U.S., and the possibility that other comorbidities, such as depression, might influence the association.

“It appears that some genes that influence alcohol dependence also influence binge eating in men and women,” said Melissa Munn-Chernoff, in a prepared statement. “When you go to an eating disorder treatment center, they don’t often ask questions about alcoholism. And when you go for alcoholism treatment, they don’t generally ask questions about eating disorder symptoms. If centers could be aware of that and perhaps treat both problems at the same time, that would be a big help.”

Women who abuse alcohol have it tough for any number of reasons, and this study gets at one of them: “A combination of pressures to adjust to the changing body at puberty, increased access to alcohol via peer networks, and genetic predispositions for eating disorder symptoms and alcohol problems could result in comorbid alcohol dependence and bulimia symptoms."

Munn-Chernoff M.A., Duncan A.E., Grant J.D., Wade T.D., Agrawal A., Bucholz K.K., Madden P.A.F., Martin N.G. & Heath A.C.  A twin study of alcohol dependence, binge eating, and compensatory behaviors., Journal of studies on alcohol and drugs,    PMID: 23948525

Photo credit: https://www.facebook.com/WUSTLmedicine.health?group_id=0

Life After Cigarettes: Book Review

Why Women Smoke.

Women are different from men. Well, maybe you already knew that.  But did you know that women smoke differently than men, and quit smoking differently than men?

Dr. Joseph Califano, the U.S. Secretary of Health, Education, and Welfare under President Jimmy Carter, once said that even though he gained thirty pounds when he quit cigarettes, he did not then appreciate the importance to women of the link between smoking cessation and weight gain. As Dr. Cynthia Pomerleau, formerly the director of the Nicotine Research Laboratory at the University of Michigan and now Research Professor Emerita in the Department of Psychiatry, remarks in her new book, Life After Cigarettes: “If we’d had a woman HEW Secretary at that time, and she had stopped smoking, I’m sure a thirty-pound weight gain would have grabbed her attention!”

In her book, Dr. Pomerleau makes clear that the challenges of quitting smoking are even greater for women than they are for men. She is refreshingly frank: “Face it; There are definitely some plusses to smoking. If there weren’t, you wouldn’t have done it, and neither would anyone else.”

For women, one of the primary pluses is, and has always been, weight control.  Pomerleau offers up the image of smoking ballerinas, women performing in a business where gaining two pounds can mean the loss of a job. Models, gymnasts, and ice skaters have also looked to cigarettes for help with weight control.

When women quit smoking, here are the facts of the matter: They will begin gaining weight almost the minute they quit—as much as three pounds in the first week—and will stabilize within three to six months. The average weight gain for women, writes Pomerleau, is ten pounds, with a quarter of female quitters gaining five pounds or less, and about a quarter gaining more than 15 pounds.  And the longer women smoke, the harder it is to battle the weight gain when they eventually quit.

The problem, Pomerleau discovered when screening patients for her Nicotine Research Lab, was that 75 per cent of the women who wanted to quit smoking said that they were unwilling to gain more than five pounds while doing so. 40 per cent of the women responded that they were unwilling to gain ANY pounds in pursuit of tobacco abstinence.

In an email exchange with Addiction Inbox, Professor Pomerleau was kind enough to expand on her message.  

When I asked her about reports that the dopamine D2 receptor gene has been implicated in both weight gain and smoking, she responded:

“In a laboratory study of food reward in smokers attempting to quit, Caryn Lerman and colleagues found that carriers of the DRD2 A1 minor allele exhibited significant increases in the rewarding value of food following abstinence from smoking, and that higher levels of food reward after quitting predicted a significant increase in weight by 6-month follow-up in participants receiving placebo.  Both effects were attenuated in participants receiving bupropion, leading them to conclude that bupropion’s efficacy in attenuating abstinence-induced weight gain may be attributable, in part, to decreasing food reward.  How well these findings will hold up to further scrutiny in larger samples remains to be seen.”

On smoking and bulimia: “As I’m sure you’re aware, the question of ‘self-medication’ is a complicated one, but it seems likely that some women ‘use’ nicotine to hold the symptoms of bulimia in check; when they quit, the underlying predisposition reemerges – which helps to explain why these women may be more prone to larger weight gain than other quitting smokers.” 

On smoking as a weight management tool: “Using a variety of different measures, it’s probably safe to say that around 40% of women qualify as serious weight-control smokers.  (The proportion is much lower in men.)  By the way, though findings are mixed, these women don’t necessarily fare worse than other women when they quit, even if they do gain weight; the real challenge is bringing them to the point of even considering quitting.”

And finally, when I asked Professor Pomerleau about the role of primary care physicians in promoting smoking cessation, she noted that she was “concerned about possible attempts to downplay the amount of weight quitters can expect to gain or to overstate the ease with which it can be avoided – which can backfire and lead to relapse when the needle on the scale begins to creep up.  I personally think it’s better to be realistic about the likelihood of weight gain after quitting and to concentrate on keeping it in the 5-10 pound range (approximately one unit of BMI and less than a dress size) – something that is in fact an achievable goal for most women.”

Photo Credit: http://www.mapleplaceventures.com/

Bulimia: What To Look For [Guest Post]

Signs and symptoms of a dangerous disorder.

[Today’s guest post was contributed by Heidi Taylor. I include it here as part of a continuing series of guest posts having to do with the so-called “lifestyle addictions,” such as perceived addictions to gambling, sex, video games, or shopping—areas in which I can claim no special expertise, and diagnoses which remain controversial among addiction researchers. However, I do strongly believe that the case has been made for the addictive nature of certain eating disorders—bulimia and carbohydrate-craving obesity in particular—in which the ingested substance is food, not “drugs” as we commonly think of them. Eating is one of the most obvious ways in which we alter the neurochemistry of our brains every day. As for treatment, serotonin abnormalities are believed to be the culprit. Many bulimics improve on SSRI antidepressants.]
--Dirk Hanson

Detecting Bulimia in a Loved One

It’s not a disease that’s visible at first or even second sight, but even so, it is one that’s largely ignored and left untreated more because most people are not even aware of its existence. But bulimia, or to be exact, bulimia nervosa is an eating disorder that could end up having physical, psychological and sociological consequences that are hard to digest. Bulimics tend to eat more than they should – in fact, they gorge on food – and then force themselves to throw up using emetics, visit the toilet with laxatives, or go without food for the next day or so. In short, they compensate for their over-eating in ways that are neither healthy nor advisable.

While it may not seem like a dangerous disorder, bulimia can have devastating consequences if left unchecked – people affected are prone to suffer from an inflamed throat and neck glands, a torn esophagus, decaying and unhealthy teeth, acid reflux disorder, ruptured intestines, irritable bowels, dehydration and malfunctioning kidneys. Besides these physical symptoms, they’re also going to be obsessed with their weight, suffer from depression and anxiety, and face other mental and social problems. So if you suspect a loved one may be bulimic, here are a few symptoms that will help you detect the disorder and get them professional help as soon as possible:

• Eating more than the normal amount possible in a single meal or over the course of a few meals.
• Frequent visits to the toilet after a meal.
• A washed out and drained look that happens because they’re dehydrated and their body is low in minerals from all the purging and use of laxatives.
• Mood swings that seem to come on for no apparent reason.
• Sores in the mouth and/or on their fingers (because they may be sticking it in their throats to induce vomiting).
• Inflamed throats and bad teeth.
• Bouts of depression or uncalled for anxiety attacks.
• Exercising for a long time, at odd hours of the day and being obsessed with the way they look.
• It’s the women and the teenagers who are more susceptible to this disorder because of their obsession with their weight and the way they look. So if you have a daughter or a close female friend or relative who acts in a way that points suspicion to bulimia, talk to them and get them much-needed medical intervention before the situation worsens.

Even if you just suspect bulimia and are not really sure, you’d do well to talk to the person concerned and get them to see a doctor who can help. Remember, it may sound like a minor thing, but bulimia is a very serious disorder.
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This post was contributed by Heidi Taylor, who writes about the Masters in Healthcare. She welcomes your feedback at HeidiLTaylor006 at gmail.com

Graphics Credit: Graham Menzies Foundation

The Biology of Bulimia

The binge-and-purge addiction.

By 2000, the biological substrate unifying alcoholism, addiction, depression, and certain eating disorders had become irrefutable. Population surveys had shown that nearly half of alcoholic patients had a long history of coexisting depression and/or anxiety disorders. Overall, about a third of patients with depression or panic disorder have had lifelong problems with drug abuse. These are estimates, best clinical guesses, but associating depression and addiction is no longer a speculative venture.

As with more familiar forms of addiction, bulimia was coming to be seen as another serotonin/dopamine-mediated medical condition. As noted, serotonin is involved in both the binge and the purge. Once researchers began performing the necessary double blind, placebo-controlled studies, it became clear that serotonin-boosting drugs dramatically lessened bulimic behavior in general, and associated carbohydrate binging in particular, in a large number of diagnosed bulimics. (Anorexia nervosa, another eating disorder, does not show the same serotonin affinities in action.)

Bulimics often maintain a normal weight, but can suffer serious physical consequence—heart rhythm irregularities, electrolyte imbalances, low blood pressure, and damage to the esophagus. Once the binge-purge cycle has been established, some researchers believe, drug-like changes in serotonin 5HT receptor distributions help reinforce the pattern. It is not surprising to learn that Prozac and other serotonin reuptake inhibitors such as dexfenfluramine were prominent among the drugs being tested against bulimia in the 1990s. By 1995, a paper presented at the National Social Science Association Conference in San Diego stated: “The serotonin hypothesis of bulimia nervosa suggests that bulimia is the behavioral manifestation of functional underactivity of serotonin in the central nervous system.”

In 1997, Prozac became the first drug ever licensed by the Food and Drug Administration (FDA) for the treatment of bulimia nervosa, as this chronic disorder is officially known. The drug’s formal approval was based on three clinical studies showing median reductions in binging of as much as 67 per cent for Prozac, compared with 33 per cent for placebo. Vomiting was reduced by 56 per cent, compared to 5 per cent for female placebo users. (About 10 per cent of diagnosed bulimics are males.) There is often a family history of alcoholism and/or eating disorders. The locus of “serotonergic dysfunction” appears to be the hypothalamus. Low levels of serotonin and dopamine metabolites have been documented in the cerebrospinal fluid of bulimic patients. Evidence exists for the involvement of norepinephrine as well.

Bulimia, like alcoholism and other drug addictions, has its psychosocial side, but twins studies show that there is very probably a genetics of bulimia to be pursued. In one influential study, an identical twin stood a one-in-four chance of developing bulimia, if the other twin was diagnosed with the disorder. A combination of SSRI drugs and some form of structured cognitive therapy is the recommended approach.

--Excerpted from
The Chemical Carousel: What Science Tells Us About Beating Addiction © Dirk Hanson 2008, 2009

Photo Credit: Graham Menzies Foundation

Bulimia as Food Addiction

Serotonin-mediated brain activity drives the binge-and-purge cycle

Bulimia, the binge-and-purge disorder that tends to afflict young women, seems especially linked to serotonin abnormalities. Bulimics gorge themselves and then induce vomiting--a debilitating cycle that often leads to severe health consequences.

Richard and Judith Wurtman, of the Massachusetts Institute of Technology (MIT) identified a subset of bulimics who binge severely and almost exclusively on high-carbohydrate foods. These bulimics tended to be mildly obese, severely depressed--and came from families with a strong history of alcohol abuse. Other researchers have reported that a significant number of bulimics are themselves abusers of alcohol and other drugs. What is being suggested is that carbohydrate-craving obesity and bulimia may turn out to be two additional forms of drug addiction. They may be variations on the addictive theme, and the underlying cause may be the same--irregularities in the reward system neurotransmitters.

For women whose bodies do not regulate the production of serotonin successfully, bulimia is one of the possible symptoms that can result from this condition. Unlike anorexia, its “partner” disorder, bulimia resembles addiction in several important ways. There is a definite “high,” which comes with the purging, and which has no analogue in anorexia. (Recall that serotonin is involved in smooth muscle functions, like vomiting and bowel movements.)

Bulimia’s impact on the brain’s reward center also seems to be quite direct, judging by the high relapse rates of bulimics. As further evidence, studies were performed by Walter Kaye and colleagues at the University of Pittsburgh Medical Center, where PET scans were taken of women who were former bulimics, and compared to a set of PET scans from healthy, age-matched women. The ex-bulimics showed a marked decrease in serotonin binding at the 5HT receptors, and studies by Kaye and others offer evidence that alterations in the brain’s serotonin pathways often persist after recovery from bulimia, and may represent permanent changes in brain chemistry.

The idea that serotonin disturbances are at the root of bulimia continues to make sense. Moreover, preliminary studies of female twins have bolstered the basic hypothesis, by showing evidence of a possible genetic predisposition toward bulimia.