When Diets Fail: Bariatric Surgery

“A Roux-en-Y gastric bypass is the strangest operation I have ever participated in… (It) removes no disease, repairs no defect or injury. It is an operation that is intended to control a person’s will and to manipulate a person’s innards so that he will not overeat again.” Dr. Atwul Gawande, Complications, 2002.

Human evolution occurred in a world of varying food supply. The body’s ability to store some fat insured survival when food was scarce. For most of us now there are no lean times when a few extra pounds  disappear, so getting rid of them means voluntarily diminishing food intake to amounts less than we require for normal activity. This is easy if we haven’t strayed more than 10-20lb over normal weight. Above this level, gains and losses tend to become cyclical – weight that comes off reappears easily, and tends to increase with each round  of dieting. When obesity becomes “morbid” – in the neighborhood of about 100 excess pounds – weight loss by conventional means is all but impossible.

A surgical way to restrict calories

So far, bariatric (from Greek words bari:heavy weight, iatr: physician, ic: pertaining to) surgery has provided the only long-term solution to morbid obesity, by restricting the amount of food entering the stomach and by altering the route the food takes through the small intestine. Patients who undergo bariatric surgery often see immediate results. Pounds finally melt away and, surprisingly, so do many previous food compulsions. Many patients maintain losses of 60-65% of their excess weight for many years. Most interesting is a profound effect on diabetes that appears before any significant weight disappears. This rapid reversal of impaired glucose control that the surgery triggers has opened a whole new frontier of research. But weight loss surgery is a drastic measure, and no one knows the results of living 30 to 50 years with this type of intestinal re-routing.

Early attempts

Beginning in the 1950s, pioneers in bariatric surgery, doctors and patients alike, learned from early negative experiences. The first approach, stapling the stomach to reduce its size, made patients lose weight, but long term results were poor. Tiny stomach pouches stretched, staple lines broke down and patients were able to eat their way back to obesity. The next approach blocked absorption of food by rerouting its path from the stomach to distant portion of the small intestine, bypassing the upper small intestine where much nutrient absorption normally  occurs. Early procedures bypassed too much small intestine and caused malnutrition, foul smelling diarrhea and a very unpleasant set of symptoms called the dumping syndrome (cramps, nausea, faintness and diarrhea). Refinements of technique resulted in fewer symptoms, though patients require supplementary vitamins and minerals, and some dumping symptoms still occur.

Modern Procedures

Today, gastric “banding” with an adjustable silicone noose placed around the upper stomach and a procedure called vertical gastric banding are the least invasive and most reversible of the commonly done bariatric procedures. They are also the least effective in terms of amount, speed and persistence of weight loss. The best operation for treating obesity is the Roux-en -Y procedure, the type of surgery most commonly meant when the term gastric bypass is used.

Understanding the Roux-en-Y

Under normal circumstances, food travels from the mouth, through the esophagus and into the stomach, which is about the size of two fists. There, it sloshes around for about 20 minutes before passing through a valve to the first part of the small intestine (the duodenum), where it mixes with bile and pancreatic enzymes. After Roux-en-Y surgery, incoming food finds only a tiny pouch of stomach, 5% of its original size, opening directly into the second part of the intestine (the jejunum). Surgical rerouting has separated 95% of the stomach and the the entire length of the duodenum from the food stream and plugged the end of the duodenum back into the system farther down the jejunum. The small amount of food tolerated by the tiny stomach bypasses several feet of small intestine before it meets up with bile and digestive enzymes.

After Surgery

Under the best circumstances, weight loss following Roux en Y surgery is prompt and long-lasting. Initially patients can eat only an ounce or 2 at a time. They must schedule meals and plan content carefully in order to meet their protein and fluid needs and to avoid constipation. Over time they can begin to eat a little more at one sitting. Most patients lose 35-40% of their bodyweight over 12-15 months, and maintain that for at least 15 years. Diabetes is cured in over 80-95% of patients. Hypertension, sleep apnea, acid reflux, arthritis, infertility, stress incontinence, fatty liver, and leg infections also disappear or are significantly improved.

Candidates for Surgery
Given all of these positive results, why not offer this type of surgery to less than morbidly obese patients who struggle to lose weight? Currently weight loss surgery is limited to patients with BMIs (Body Mass Index) of 40, or 35 if the patient already suffers from obesity related diseases like hypertension or diabetes. BMI is a calculation of weight divided by height squared, with measurements expressed in kilograms and meters. A BMI of 30 qualifies a patient as obese; 19-24.9 corresponds to appropriate weight. Statistical analysis of risks and benefits of bariatric surgery set the acceptable range for surgery. Surgical candidates must also undergo extensive medical tests and psychiatric analysis, and have made serious attempts to lose weight. They must understand that gastric bypass is drastic and usually permanent, that complications can be bad, and that success is not guaranteed. Some patients manage to regain all their weight and then some.

Oversight

Bariatric surgery is regulated by American Society of Metabolic and Bariatric Surgery, which sets professional standards for hospitals and surgeons, establishes centers of excellence, and promotes research and data collection about the procedures. In 2007, surgeons performed over 200,000 surgeries for obesity, up from around 16,000 in 1992. Advances in laparoscopic surgery have made recovery faster and less uncomfortable. The best surgical mortality rates are 1% and peri-operative complication rates 10% – acceptable numbers given the worse risks of morbid obesity.

Complications and Long Term Results

Possible complications of bariatric surgery  include blood clots travelling to the lungs, heart attack, respiratory compromise, suture line leaks, hernias, ulcers, GI bleeding, bowel obstruction, and gallstones. Calcium iron and some vitamins are not well absorbed and they require life-long monitoring and supplementation. All bariatric surgeons emphasize that long term success depends on patient cooperation with major eating and lifestyle changes forever. This is especially important when the choice of procedure involves only change in stomach size, as is the case with the gastric banding procedures.

Clues about metabolism and diabetes

Sheer calorie restriction accounts for some of the success of all types of bariatric surgery. When the surgery also bypasses a segment of small intestine, more is at work than meets the eye. The rapid disappearance of diabetes before significant weight loss occurs and the remarkable loss of previous cravings are clues to unappreciated biochemical and hormonal complexity of the intestines. The surgical assault on obesity appears to have much to teach us about energy metabolism and diabetes. One day, hopefully, such strange surgery will be unnecessary.

Resources:
American Society of Metabolic and Bariatric Surgery (http://www.asmbs.org/): Access to readable, professional information regarding bariatric surgery.
http://www.obesityhelp.com/: Support group website for patients contemplating surgery or looking for related information

Holding the Line: Stop Gaining First

One of the most remarkable failures of modern medicine is its inability to combat obesity and its associated ills. Obesity is not a new human condition, nor will it ever completely disappear. But since the 1970s, something has changed in the environment and culture to make the condition epidemic, despite sophisticated medical research, a multi-billion dollar diet industry, and constant media attention.  The most effective solution remains not gaining excess weight in the first place, but that is no longer an option for over 60% of the population, many of whom are veteran dieters.

The body wants to keep the fat

Diets depend on adherence to a long-term plan for eating that fails to meet the body’s need for energy.   In response to this semi-starvation, the body mounts a defense. Hair and fingernails grow more slowly. Heat generation declines and the dieter feels cold and is less inclined to move around. Cells throughout the body ramp down their energy needs.  Within a few days, even sleeping burns fewer calories.  Caloric requirements remain suppressed long after the target weight is achieved.  Upward weight creep begins as soon as vigilance about food intake and exercise declines, and happens at a lower calorie intake than in the pre-diet days.  So begins the yo-yo dieting cycle, unless the dieter just gives up.

Stop the upward creep first

Giving up the attempt to starve away the pounds will eventually bring the metabolic rate back up, but only as the pounds re-accumulate. At this point a tactic other than a repeat diet attempt may be in order.  The most reliable way to achieve weight loss that lasts is by burning slightly more energy than is consumed on a daily basis over a long period of time – a sneak attack rather than a frontal assault.  Such long term daily commitment requires habit formation, and habit formation requires patient repetition of actions over long periods of time. Holding weight stable- just simply trying not to gain any more for at least 6-12 months- is the first preparation for mounting a sneak attack.

Going on defense

In contrast to the coordinated offense of a diet plan, not gaining any more weight requires defensive tactics.  Mindfulness – thinking before eating – is the primary tool.  Each day presents dozens of choices that might contribute to weight gain – or not. The only concern is reacting to choices presented.  Reacting correctly to just a few of them every day adds up over time.  At the end of 6-12 months of no weight gain, you are better off than at the end of another diet cycle that winds up on the upside of the starting weight.  You’ll have the habits of a person who maintains stable weight, and you will be ready to lose weight slowly and permanently by undershooting energy requirements just a little each day – but not enough to put your body into energy conservation mode.

Learn from the people who succeed

People who maintain stable weight often have some sensible guidelines for themselves. A common behavior is refusal to buy larger clothing sizes. Another is the choice of clothes with zippers and buttons and belts. If clothing becomes uncomfortable, they cut the sweets and alcohol back and pay more attention to activity level.  A weekly weight check keeps others on track. These people know better than to obsess about daily weight fluctuations, but 3-5pound gain in a week gets their attention. While a common mindfulness tactic is procrastination of eating to sort out true hunger from urges of emotional origin, people who maintain stable weight also do not go long periods without eating. The body begins to downshift into a lower energy gear if no food appears to break a fast of more than 6 hours.

Choices, choice, choices

Easily digestible carbohydrates in the modern diet, especially those combined with fats, make good targets for people seeking stable weight. Carbohydrates trigger surges in insulin.  Insulin blocks fat usage for energy needs, and hunger recurs much sooner after a high carbohydrate snack or meal than after one containing more protein and fat.  Choose to keep insulin levels down: eggs instead of cereal; one slice of bread on a sandwich instead of two; one M&M instead of a handful; nuts instead of M&Ms; half the normal spaghetti serving – or eat just the meat sauce; drink water instead of juices or soft drinks, even diet ones. (The taste of artificial sweeteners also triggers a burst of insulin, even though they have no caloric value.) Put off eating something that you really don’t need – distract yourself with an activity or task. Practice self-control in other areas of life. Self-control is a “transferable skill” and any practice helps build it.

Activity choices abound. Park far away from your destination. Walk if the trip is less than a mile (get a pull cart for groceries if you are lucky enough to live near the store). Skip the elevators. Make dates for walking instead of eating. Keep your hands busy and mind busy (mental activity takes energy too). Sit on an exercise ball instead of a desk chair. If you have a wireless printer, put it far away from the computer – on another floor if possible. Mow your own lawn. Shovel your own snow. Buy a pedometer and watch the steps add up. Engage in some strengthening activities to build high-energy demanding muscle tissue.

Stay in the present

Dieting to lose weight is always focused on the future. Weight maintenance is a present-moment task. There will never be a better time than now to go on the defense and begin to stop gaining weight. Now is the only time you have in which to take action – all the rest of time is either a memory or an imaginary future.

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