Why are gastric-bypass patients at risk for alcoholism?
There is indeed a connection, and it’s worth knowing about. Before I get further into it, I feel the need to state for the record that I’m not trying to discourage people from considering the gastric bypass. The bypass is a great weight-loss operation. Besides being a fantastically effective treatment for type-2 diabetes and other obesity-related diseases, gastric bypass surgery also results in an amazing 30% to 70% drop in the 10-year all-cause mortality (death rate) of patients who undergo it, relative to similar patients who could have but didn’t. All-cause mortality, by the way, is a figure that includes anything and everything that happened to the various studies’ subjects. It includes any complications of surgery, and even weird, “Final Destination” type occurrences (e.g., “hit by a bus”) count in an all-cause mortality analysis.
It’s important to understand that 30-70% is a huge drop in all-cause mortality. Other than smoking cessation, I can think of no elective health intervention or lifestyle change whose benefit even comes close to it.
The relationship between bypass surgery and alcoholism is real, but it’s not super-strong. Most bypass patients won’t develop it. The research shows that beginning two or three years after surgery, bypass patients start seeking treatment for alcoholism at a higher-than-expected rate. In absolute terms, it’s like one extra person out of twenty to fifty patients. It’s a modest increase, but it’s significant. Because of it, I tend to counsel patients with indicators of addictive potential that they may do better with sleeve gastrectomy, ESG, or medical therapy.
Why are gastric-bypass patients at risk for alcoholism? In short, we don’t know. In medical circles, speculation centers around the fact that alcohol is absorbed into the bloodstream more quickly after gastric bypass. This absorption hypothesis doesn’t explain how faster absorption increases addiction risk, and it’s not obvious to me why one should follow from the other.
The popular media favors the idea of “cross addiction.” Oprah Winfrey aired an episode about it. Cross addiction posits that when people are thwarted from participating in one addictive behavior, they seek a substitute. Obese patients, thwarted by surgery from indulging in food addiction, supposedly turn to alcohol to fill the void.
I admit that cross addiction is a superficially attractive theory. It is certainly a tidy, logical-sounding explanation for the alcoholism seen in bypass patients. That said, I don’t believe it’s correct. If it were correct, then people who lost a similar amount of weight through other means (e.g., sleeve surgery, injectable medications) should incur the same alcoholism risk. We know that they don’t.
My personal suspicion is that hypoglycemia (low blood sugar) is the missing piece of the puzzle. Understanding how chronic hypoglycemia leads to alcoholism requires understanding two aspects of physiology: how bypass surgery alters absorption of sugar, and how the human pancreas responds to a high blood glucose level.
As to absorption, it’s not just alcohol that’s absorbed more quickly after bypass surgery. Sugar absorption is sped up to an even greater degree. Because sugar is absorbed more rapidly, bypass patients experience sharper blood-sugar spikes than non-bypass patients. The rise in blood sugar is sharper, and the peak blood sugar level is higher than anything experienced before surgery.[1] These repetitive spikes in blood sugar are the problem that leads to chronic hypoglycemia later.
Often, the immediate effect of a blood sugar spike is an episode of so-called “rebound hypoglycemia.” Anyone who ever felt jittery and hour after drinking a can of Coke on an empty stomach is familiar with it. Your blood sugar spikes in response to a sugary drink, and your body responds by releasing insulin. Insulin is a hormone that tells every cell of the body to start pulling sugar out of your bloodstream, lowering your blood sugar. If the blood sugar spikes really high, you release a whole lot of insulin. Too much, in fact. A big blast of insulin doesn’t just return our blood sugar to normal; it causes it to overshoot the target. The cells sucking up sugar under the influence of insulin can’t stop on a dime, and often when the falling blood sugar hits the normal range again … it keeps on going down! The insulin wears off before long, but before it does, the sugar sometimes can fall to levels that are uncomfortably, even dangerously low.
While rebound hypoglycemia is the most noticeable consequence of a sugar spike, in the long term, it is not the most important one. The long-term effect of experiencing repeated spikes in blood-sugar has a more ominous effect: massively increasing insulin production and release. That increase is what leads to substance abuse (more on that in a moment).
Why do blood sugar spikes cause your pancreas to boost its capacity to make and release insulin? Well, it’s because as far as your body is concerned, refined sugar is poison. There is no source of refined sugar in nature. Prior to recent times, it was simply unavailable to humans. As a result, our bodies are completely unprepared to handle it. A half hour after a normal person drinks a can of Coke, their blood sugar hits 170 mg/dL or higher. Excepting the last few generations that lived when sugar was around, if you went back 100,000 years in that person’s family tree, you would not find a single soul that ever experienced a blood sugar that high in their entire life, however many decades it was.
Your body reacts as though that blood sugar of 180 is a potentially fatal emergency. It pulls the fire alarm. Not only does it release as much insulin as it has in store at that moment; the blood sugar spike also sends a strong signal to your pancreas to increase its ability to make insulin tomorrow. And the next day. Those repetitive sugar spikes end up exercising your pancreas in the exact same way that Arnold Schwarzenegger used to exercise his biceps at the gym. Every sugary treat is another blood sugar spike, which is another rep in the weight-training of your pancreas. Before long, your pancreas’s ability to make and release insulin grows monstrously out of proportion—like Arnie’s biceps.
All the extra insulin causes lots of hypoglycemia. You experience rebound hypoglycemia after eating sweets of course. But even between meals, the baseline level of insulin your pancreas is putting out is too much, and that drags your blood sugar down.
The reason that lower-than-normal blood sugars lead to substance abuse is that we experience low blood sugars as anxiety. Remember how jittery you felt an hour after downing that can of Coke on an empty stomach? Those jitters were the result of adrenaline release. When your blood sugar dips, your body responds by releasing adrenaline, the fight-or-flight hormone, into your bloodstream. Adrenaline makes us feel anxious. That’s where the anxiety comes from.
The link between anxiety and substance abuse is straightforward. If insulin overproduction gets bad enough, anxiety can become a regular part of life. People who might be prompted to consider using a substance (alcohol, for instance) to quell an episode of anxiety will start to feel an increasing temptation to use. The more pervasive and intense the anxiety, the worse the temptation.
Fortunately, the patients I’ve known who have developed this problem have been able to reverse it by eliminating sweets (sugar and artificial sweeteners) from their diets. Once those things are eliminated, the anxiety quickly gets better. It takes about a year of sweets avoidance for insulin production to get completely back to normal, however. Think again of the Arnold Schwarzenegger analogy (which is very apt, by the way). During Arnold’s prime, if you saw him after he skipped the gym for a week, you’d still be looking at Conan the Barbarian. If, on the other hand, he had skipped for a year, now you’re looking at a normal guy. So it is with pancreases!
My advice to all my bypass patients—and all my other weight-loss patients, for that matter—is to avoid sugar and sweeteners like the plague. I really believe those things are (for all practical purposes) poison. They’re just slow poison, like cigarette smoke.
[1] These changes to absorption are why the standard test for gestational diabetes, the three-hour glucose tolerance test, cannot be used in gastric bypass patients.