July 6, 2009

The REAL Truth about Gastric Bypass's Supposed "Cure" of Type 2 Diabetes

You have probably heard a lot by now about how gastric bypass surgery can cure diabetes. Quite a few of my correspondents who are significantly overweight report being pressured by their doctors to sign up for weight loss surgery (WLS). Some family doctors are going so far as to refuse to prescribe less invasive treatments for high blood sugars in favor of insisting their patients have WLS.

Given this bias, it's worth looking closely at two new studies presented at the recent Annual Meeting of the American Society for Metabolic and Bariatric Surgery

First off, you need to understand that this convention is not an objective scientific gathering. It's the annual trade group meeting of the surgeons who profit--to the tune of $20,000 or more per surgery--from doing WLS.

The organization's membership is open to any licensed surgeon who has performed 25 weight loss surgeries. Associate membership is open to just about any medical professional willing to pay the membership fee. This group does not certify WLS surgeons. It does not even insist that the surgeons who join the organization prove that their patients survived the surgery or had good outcomes.

The mission of this WLS trade group is simple: to promote WLS and to provide "research" that will motivate insurers and Medicare to pay for ever more surgeries.

With that in mind, let's look at the studies presented at this latest conference because they are being reported in publications targeting endocrinologists and family doctors as showing that "Data confirms long-term effects of bariatric surgery on Type 2 diabetes."

I do not have access to the actual report, but there is a lengthy summary of it which appeared in the newsletter, Endocrine Today, which gives enough information to help us evaluate what the study really found.

The report begins by quoting a Dr. Christine Ren, identified only as an "associate professor of surgery at New York University School of Medicine," who says,
“This is a strong message to physicians and endocrinologists that gastric banding should be very seriously considered in the morbidly obese diabetic population because it offers the best chance to have better control or remission of their diabetes long-term [emphasis mine].
Unmentioned in the report is the fact that Dr. Ren advertises herself publicly, on a web site that at the time had the URL"thinforlife.med.nyu.edu" as "the Leading Surgeon for lap band surgery in the U.S." So she is hardly an objective source of endocrinological advice.

Dr. Ren's study gathered preoperative data on 95 patients (mean age, 49.3) who underwent laparoscopic adjustable gastric banding between 2002 and 2004. Five-year follow-up data were collected beginning in 2008.

She states, "At the five-year follow-up, mean BMI decreased from 46.3 to 35.0 — a mean value of 48.3% excess weight-loss."

As Dr. Ren explained it, “There was a sustained benefit — about 40% of patients had complete remission in their diabetes"

Complete remission sounds wonderful doesn't it? But what does "remission" really mean? Well, it turns out to mean this: "Mean fasting glucose decreased from 146 mg/dL preoperatively to 118.5 mg/dL at five years; mean HbA1c decreased from 7.53% to 6.58% (P<.001). "

I don't know about you, but I can get much better numbers than that without having my stomach permanently altered. I did it for seven years only by cutting way down on carbohydrates. Hundreds of my readers do this too.

But I would not consider a fasting blood sugar of 118.5 mg/dl (6.6 mmol/L) "complete remission." Nor would I consider an A1c of 6.58% nondiabetic.

And I'm not alone in this. The ultra-conservative ADA recently updated their position statements to define an A1c over 6.5% as diagnostic of diabetes.

The reason given by the ADA experts for choosing 6.5% as the diagnostic cutoff is that the incidence of retinopathy starts to rise significantly when A1c goes over 6.5%, though if you look at the data the ADA experts cite in their report, the incidence of retinopathy actually starts to rise when A1c goes over 6.0%. I urge all of you to read the ADA Position linking A1c to Diabetes diagnosis.

We all know that retinopathy is a relatively late diabetic complication. The ADA continues to use the presence of retinopathy as a diagnostic indicator for Diabetes, but since Retinopathy develops years after sudden onset diabetes (Type 1) that criterion makes as much sense as diagnosing AIDS by waiting until people develop brain lesions.

Other data suggest that heart disease incidence rises dramatically when A1c goes over 6.0% and that of neuropathy and kidney disease probably do too--as they begin to rise when post-meal blood sugars reach the pre-diabetic range.

Dr. Ren goes on to say,
"about 40% of patients had complete remission in their diabetes. This was confirmed with normal fasting blood sugar, normal HbA1c and they were completely off all medications including insulin,” Ren said. “In addition, there were another 40% of patients who had improvements in diabetes as shown by a decrease in their medication, improvements in fasting blood glucose control and improvements in HbA1c.” Diabetes was resolved in 43% of patients, for a total improvement/resolution rate of 83%.
If we define "complete remission" of diabetes as achieving A1c under 7% and FBG under 125 mg/dl, my guess is that a lot more than 43% of us have "resolved" our diabetes with much less invasive approaches. Even if we define a diabetes cure as meaning we achieve truly "normal" blood sugars--i.e. FBG under 100 mg/dl and post-meal numbers under 140 mg/dl at two hours after eating, most of my long term readers may be surprised to discover they have long been are "cured" of their diabetes.

A second study presented at the WLS trade show looked at long term outcomes of the even more dangerous Roux-en-Y gastric bypass surgery, where a large portion of the stomach is permanent amputated. Its findings also make it clear that the diabetes "cure" through WLS is completely illusory.

This study reports,
Complete resolution was achieved in 157 patients who also had a decrease in mean BMI from 50.2 before surgery to 31.3 after surgery. Forty-three percent of these patients subsequently had type 2 diabetes recurrence and associated weight gain [emphasis mine].
The chief researcher in this study is quoted as saying, "“When looking at the insulin-controlled diabetic patients, 80% had resolution at some point, but recurred in 72%."

So let's get this straight. Amputating a large part of people's stomach resulted in a transient resolution" of diabetes, that did not last for almost half of them. Only 8% of those who were already diabetic enough to need insulin ended up better off than before they had the surgery.

How much more modest this data is than the results that were all over the media from other studies that claimed diabetes immediately went away in people who had WLS, "Like magic" and did not mention that this finding was based on blood sugar results a few weeks after surgery when the patients were not able to eat any carbs!

If we define "remissions" as dropping FBG or A1c just below Diagnostic Criteria for diabetes, a moderately low carb diet will achieve a higher rate of "remission" with the same or better long term statistics. And it will do so without risking the patients' life or condemning them to life-long nutritional problems.

What leaves me gasping with shock is this: the death rate of these surgeries runs quite high. You can read about the latest metastudy that came up with the statistics, HERE. Though the article was titled "Large Scale Analysis Finds Bariatric Surgery Relatively Safe," what was actually reported was a death rate of ".135% with 78 deaths reported among 57,918 patients."

No oral drug could ever be approved or sold to the public that killed 13 out of every thousand people who took it. But surgeries are not regulated. So surgeons have been performing WLS for decades even when they knew the death rate from this surgery was as high as 3 in every hundred.

Reading between the lines, this latest study was run in a cherry-picked fashion as in, "The data was accrued from participants in the ASMBS Bariatric Surgery Centers of Excellence program." The criteria for being a part of that program is undoubtedly a low mortality rate. So this statistic does not tell you what the death rate among average patients and doctors might be. The numbers I have seen elsewhere range from 1-3%.

Other studies have found the death rate from WLS much higher in some populations and found--more importantly--that it rises when the surgery is performed by doctors with little experience or skill. Since you have no way of knowing how skilled your surgeon may be, as doctors cover for each other and do not let word of their colleague's incompetence or drug addiction or alcoholism to become public, you have no way of knowing what your doctor's personal kill rate might be when you sign up for surgery.

But even those who do not die of the surgery--and some of those whose diabetes "goes into remission" are at high risk of serious nutrition deficiencies after WLS. This is because altering the stomach often destroys the ability to absorb important minerals. This nutritional deficiency syndrome is so severe that a 2009  Mayo Clinic study found that people who have had WLS have twice the risk of fractures as the normal population.   A review published in 2017 updated this finding with citations of many more studies confirming the serious impacts of nutritional deficiencies caused by weight loss surgeries. 

Many people who have had the surgery must go to the hospital periodically for intravenous mineral supplementation without which they can die.

IF your doctor suggests that WLS is a quick way to eliminate your diabetes, remember that he learned this "Fact" from the studies that looked at blood sugar a few weeks or months after the surgery when the stomach is so tiny people cannot eat enough carbohydrates to see elevated blood sugars.

Remember too that the studies show that people with diabetes who need insulin probably won't see an improvement, because if your beta cells are dead, the surgery is not going to be able to fix them.

All WLS does to "reverse diabetes" is make significant carb restriction non-negotiable. Eat enough carbs to raise your blood sugar, early on after the surgery, and you'll vomit it all back up. There isn't room in your tiny stomach pouch for enough food to raise your blood sugar.

Over time the pouch stretches and your blood sugar will go right back up as you eat more food. You didn't reverse anything. You simply lowered your blood sugar by making it impossible to eat carbs.

You can cut way back on carbs without surgery. Metformin can cut way down on hunger and when combined with a carb restricted diet can also give you blood sugars at least as good as what these surgeries produce, and possibly better.

But don't expect to hear this from the media. The WLS surgeons have unleashed a formidable PR machine. They make their claims on TV unchallenged. They promote their surgeries with highly questionable research conducted by doctors who profit personally from the growth of the WLS patient base.


Unknown said...

You make some good points. However, the study you link to to support your 1% mortality statistic actually indicates a very significantly lower mortality rate - more like a tenth of a percent - unless I misread it somehow. Here's the relevant quote: "Total mortality rate was under one percent (0.135%) with 78 deaths reported among 57,918 patients."

Jenny said...

Good catch. The mortality was under 1%, however these statistics were from a subgroup of "The data was accrued from participants in the ASMBS Bariatric Surgery Centers of Excellence program." This suggests to me that it has been carefully cherry picked.

You don't get to be one of their "Centers of Excellence" if you have a higher mortality percent, so they will end up with a lower than typical mortality figure.

Non cherry picked statistics show a much higher complication rate and a much higher death rate.

ItsTheWooo said...

I often wonder if we will look back at this surgery similar to the lobotomy. Like the lobotomy, it started out validly (as a very last resort for the incurably / severely mentally ill before thorazine) ... but then greed and egos pushed it to the point where they were performing it on "childhood schizophrenics" and migraineurs. That's when it became an attrocity.

I see gastric surgery as similar to that. If used in a very morbidly obese person with medical complications who truly HAS tried to diet and is unable to control his/her food intake for any length of time... then it is worth a shot, you know, sort of a last resort.
But now it's being performed on only marginally obese people, people who are healthy, people who really haven't put an honest effort into losing weight (even if they claim they have). This surgery is no joke.

The only contention I have with your blog post is related to the fracture risk in post bariatric patients. While it is true that the surgery often causes nutritional deficiencies because of how the small intestine is bypassed, especially in earlier/more extreme versions, it is also true that massive weight loss itself will cause osteopenia/porosis. This occurs whenever a morbidly obese person reaches a "normal" weight. During massive weight loss of this extent IGF-1 levels fall low, and bone mineral density is lost. I never had gastric bypass surgery and I have osteopenia now because of the fact I lost 160 pounds.

In the morbidly obese, weight loss, regardless of how it is achieved, is almost always perceived as starvation by the body (IF the loss is so extreme that BMI becomes "normal"). This is my conclusion after extensive research and living in my body. Osteopenia/porosis is a complication for all "normal weight" post morbidly obeses, much like it is for food deprived/eating disordered/underweight people.

Pubsgal said...

Wow, thanks for posting this. I have to admit that I was extremely skeptical about WLS as a "cure" for diabetes, especially having had a sister-in-law have the surgery (for other medical reasons)...what did they consider "cured"? I always wondered what would happen if people followed the regimen of post-WLS, without having had the surgery, and how that would affect weight loss and diabetes.

Happy to say that I went with the "5% Club" method, and I am maintaining a 75-80 lb weight loss as well as having an a1c of 5.3%. Just diet (and not a depriving one, either!), exercise, and metformin. It *is* possible! (And, before diagnosis, I would never have thought it so.)

Anonymous said...

Myriad inaccuracies in your point of view cannot be done justice in a single comment....let's just look at the "ultra conservative ADA" as you called it. In February 2009 they made it part of the STANDARD OF CARE FOR THE TREATMENT OF TYPE 2 DIABETES to consider bariatric surgery in patients with a BMI over 35....
I doubt this comment will survive "moderation" because far be it for facts to get in the way of your opinion, but those are the facts.

Jenny said...

The ADA will support any strategy no matter how dangerous to patients that enriches a doctor or drug company.

What irony if they've decided to push WLS as a diabetes treatment, after they have warned for years that, even though a mass of evidence shows low carb diets to be safe and very effective for people with diabetes, "More research needs to be done" before they can recommend them because some vague unspecified danger might eventually turn up.

Meanwhile they rush to recommend this dangerous, extreme surgery whose dangers are very clear and whose effect on diabetes is no better than that of the low carb diet.

I wonder how much the WLS surgeons contributed to the ADA to get them to make that recommendation. The ADA has a long history of promoting the products and services of their corporate and medical sponsors.

They certainly have NO history of ever doing anything that involved standing up against those doctors or corporate interests because they might benefit we people with diabetes. The only time they seem to remember us is when they use our plight to raise money to pay their overpaid executives.

MyDailyQuestion said...

Help me understand this.

Isn't the whole point of weight loss surgery to get the mutilation victim ... I mean, surgery patient ... to eat less food?

What is so hard to understand about just eating less food?

I don't mean to understate the difficulty of weight loss diets, because I've struggled with my obesity for decades. However, by finally sticking with a careful low-carb diet, I'm normalizing my Type 2 diabetic blood glucose, losing weight, and feeling great. It can be done, if people are well-informed.

And you're an excellent source of information.

Ian said...

Australia's Science Show had an interview with a New Zealand gastric surgeon who claims that bypass surgery (not banding) cures diabetes, and not just by reducing carb intake or reducing patient weight.
There's a transcript here:

Jenny said...


This doctor's claim is not new. It was in the news a lot a year or so ago, mostly based on rodent research.

But the carefully cherry picked data in the study I blogged about doesn't appear to confirm the surgeon's anecdotal report.

One important thing to remember is that the surgeon spends very little time with the patient. If there are no complications, he will see them one more time at 6 weeks and then never again. So there is no real followup.

So they are mainly evaluating the patient in the first 6 weeks after the surgery. There may be some transient effect on gut hormones in that period. But remember, doctors have NO idea of the power of cutting carbs. Yes, if you have a diabetic eating nothing their blood sugar will go up. But if you feed them a low carb diet after a few days it will go down and stay down.

When I was in the hospital the diet the doctor insisted I eat was toast, bananas, and sugar free jam or if I preferred pancakes with sugar free syrup.) That tells you how much they understand about blood sugar's response to diet.

Scott S said...

The medical profession has a nasty habit of failure to disclose apparent conflicts-of-interest, and this is just the latest example of this, but there are many, many more. As patients, we should always be asking 1 key question about any study with a conclusion that needs to be proven wrong: "if it looks too good to be true, chances are, it probably IS". The conflicts-of-interest, even among such supposedly peer-reviewed medical and scientific journals make a mockery of the notion of "evidence-based" medicine!

Unknown said...

MyDailyQuestion, the key is eating low carb, not simply eating less, as you may have discovered. In obese people (and those prone to it, like I am), metabolism is damaged to the extent that eating high carb promotes not only weight gain but internal cellular starvation at the same time.

Try out Gary Taubes' book "Good Calories, Bad Calories" if you're interested in the science behind obesity, diabetes, and other diseases of civilization.

Trinkwasser said...

I mostly agree, but ISTR Gys (waves if he's reading) among others dug out some work suggesting the surgery actually did interfere with some control system: my money was on incretins.

Obviously it would be better all round to find a more effective way of interfering with the same control system, either medical (Byetta) or "lifestyle" like that dreadfully dangerous low carb diet that if they'd followed up on Gannon & Nuttall the ADA could now have had long term studies over nearly a decade and might actually be considering to be less harmful than surgery


I must have been dreaming again

Unknown said...

please people dont do it. i had gastric sleeve. i thought 60 precent of my stomach was going to be removed. they removed 90 procent. i made the biggest mistake of my life. i went from a healthy energetic young women into a depressed person. i was eating very healthy. i made a terrible mistake. my life quality went down by 90 precent and i hever never been more unhealthy in my life. i never had the flu in 9 years. o thow i was obesed i did al lot for my health. i swim 3 times a week. i ate al lot of veggies and fruit. please wls is going to ruin your life. it is my biggest mistake. my life is gone. so please especially if you are healthy you can only loose.

Tina said...

I had the gastric bypass surgery 2 1/2 years ago to treat diabetes. My glucose was normal by the end of the week. I am off all medication and my AIC went from 8.9 to 5.0. I am very pleased with the surgery and I would do it again , without blinking an eye. I've had no complications and it saved my life. I

dd25 said...

Good point Tina. This blog's author did not write one word about how the bypass part of the surgery changes the output of gut hormones that cause insulin to increase. THAT is how bypass surgery cures diabetes, by restoring a normal insulin response. There are already trials taking place that are performing just the bypass (no stomach restriction) for T2 diabetics who are not obese. Again, the blog's author never bothered to mention one thing about the gut hormone issue, which makes me question her credibility.

Jenny said...

You can modify the same gut hormones by taking Byetta and achieve the same effect without permanently altering your digestive tract. I know quite a bit about the gut hormones, including the fact that the way the surgery can affect them is the reason why some people who undergo bypass surgery develop the anorexia which kills them. Gut hormones like GIP and PYY affect the region in the brain, the hypothalamus, which regulates appetite and also affects memory.

There is a place for this surgery, and I know people who have benefited from it, but it makes major, often irreversible changes to the body whose repercussions won't be fully understood for a decade or more, and like so many medical treatments it is being oversold.

Unknown said...

I feel the complete oppesite I had gastric bypass 8yrs ago weighing 425lbs at 5'10 both my grandmother my mother and my brother have dibetis. All overweight. I am 230lbs and my blood sugar is great. Today it was 86. I am 42 and my brother is 43 all family members that have it were diagnosed with it in late 30s and all my test results continue to be normal on everything I would recommend wls to anyone who is obese I would not change a thing!