Posts tagged:Diet

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

Posted by medical plaintalk

Physician turned medical writer.

Common Sense Eating

    My acerbic Irish grandmother would take a look at our modern obsessions with nutrition, light up a Camel, and ask what good comes of all the worrying. She’d have a point. After fifty years of expert advice on diet, what do we have? The fattest society on earth, an epidemic of diabetes, and the first generation that will not meet, let alone exceed, the life expectancy of their parents.

We live in bodies exquisitely suited to life forty-thousand years ago. The sweetest things on the planet were some sparse berries. The only drink was water. No one fattened up wild game with corn. Getting food required considerable expenditure of energy, and who would waste energy chasing more food than they needed? But just in case extra food came along, the body was equipped with a highly efficient means of squirreling away the excess as fat, to cover inevitable times of short supply. Lights went out when the sun went down, and everyone rested up for the next day’s pursuit of food.

These old-fashioned bodies are now awash in too much food that is too easy to obtain, and in manufactured food full of unnatural, but edible chemicals.  We are also awash in advice, calorie counts, carbohydrate grams and recommended daily allowances.  Looking at the results, our grandparents might guess that the average man is more in need of common sense than tables, charts, diets and recommended daily allowances. So here are some common sense suggestions about how to navigate the modern world of food.

Shop the perimeter of the grocery store

Everything your body needs is out there. Don’t skip any of the departments, spend the most time and money on fruits and vegetables, go for color,  avoid sugar,  and remember that there are vitamin and micronutrients  in dairy products, meats and fish that are scarce elsewhere. Egg whites are one of nature’s best proteins. The closer food is to its actual source, and the less the processing, the better its nutritional value.

In the middle aisles, stick to a list

There is nothing in this part of the store that you need for survival, but there are cooking essentials like olive oil and spices, convenient staples like canned tuna and tomatoes, and whole-grain, high fiber cereals.  Look for packages with the fewest ingredients.  Remember – “natural flavors” often come from manufacturing plants on the New Jersey turnpike, soy protein is a very unnatural derivative of the manufacture of soybean oil, vegetable oils that go rancid are not good for you, and oils derived by cold pressing are closer to their original sources than those that are refined like petroleum.

Opt for fresh food over manufactured food whenever possible

The addition of high fructose corn syrup and preservatives to almost every packaged food gives us cheap, long-lasting and attractive products, but think of these foods as emergency rations. If you built your home with poor materials and filled your car with unsuitable fuel, they might hold up for awhile, but over time they would suffer premature failure. Fresh and frozen foods that haven’t strayed too far from their original sources are the materials and fuel your body is built to handle.

Think regular meals with  smaller amounts and balanced composition

We are designed to need a balanced mixture of food every 4-6 hours (while awake). Your hand is a rough guide to amount and mix of food for each meal. You need protein, carbohydrate and fat and you don’t need to read labels to know if you are getting them all. Protein comes from living things that were able to move around on their own, and necessary fat comes along with protein. Beans are the only exception and their protein comes by virtue of bacteria which transport nitrogen into the roots of bean plants and which do move around.  Carbohydrates come from stationary living things. The carbohydrate portion of a meal should cover the palm of the hand.  The protein component fits in the area from the base of the thumb to the big central crease. The fat that you need comes along with your protein source, in the olive or coconut oil needed for cooking, and in any milk you drink.For perspective on old fashioned eating, consider a sample meal in a California museum that is a replica of a hotel of the Gold Rush era. Dinner consists of a hard roll, an apple, and a few clams and some leafy greens floating in a thin broth – fuel enough for the people who did the hard labor of building this country.

Make the time to prepare food and eat in a nice setting, with good conversation

Get back to the way your body is designed to eat, the way people have eaten for thousands of years, and you’ll save time by being healthier and more energetic and not having to read diet articles.  And lighten up – a small amount of ice cream or pie or chocolate now and then is fine. Amount is the key.

Choose water

If you are thirsty, you need water. If you want liquid to help wash down food, pick water.  If you want water to taste like something else, choose a liquid that lacks high fructose corn syrup and has some nutritional value: fresh, pulpy juices with their vitamins and fiber, or  milk, with its protein, minerals and vitamins.  Coffee and tea? Fine. No one has ever been able to pin much bad on either one, in moderation. Ditto for wine, in even more moderation.

Avoid fake food

Artificial sweeteners – a real boon for diabetics – are unnecessary chemicals for everyone else. There is no evidence that artificial sweeteners promote weight loss. They may even lead to weight gain.  Not worth it for the mere 12 calories in a teaspoon of sugar.  And margarine? Even ants won’t eat that (but they do like butter).

We are where we are after over half a century of harping on fat and cholesterol. Common sense tells us they can’t be the only problems. Common sense is what we need – along with a diet, sleep and physical activity suitable for life 40,000 years ago.

Posted by medical plaintalk

Physician turned medical writer.

Vitamins: Is Nature’s Magic Enough?

When I was a medical intern I watched my supervising resident perform an immediate and visible cure and in that moment understood the appeal of vitamins to our pill-loving culture.  We were laboring over an old gentlemen brought to the emergency room from Boston’s Commons – a park that was home to many people whose diets came largely from brown-bagged liquor bottles.  Our patient was agitated and confused. Try as we might we could not get his eyes to move in any direction. My resident disappeared and returned with a tiny syringe filled with a Vitamin B1, also known as thiamine. He injected the liquid into the patient’s vein and, as if he’d waved a wand, our patient’s eye movements returned and he calmed down. Here was a miracle drug, and it was something nature made for us.

Vitamin deficiency

The magic of our patient’s recovery was a clear example of the function of vitamins. In minute amounts, they act as facilitators of chemical reactions necessary for energy production and cellular maintenance of all kinds. Our patient had a textbook case of vitamin deficiency, the result of a very bad diet or failure to absorb vitamins from the stomach and small intestine, or both. Alcoholism is the most common setting, but vitamin deficiencies occur with other severe gastrointestinal problems and in the malnutrition associated famine or devastating illness like cancer and AIDS. Sometimes medical treatment itself is the perpetrator, in the form of anticancer drugs or bypass surgery for morbid obesity.

Vital nutrients

For thousands of years, people have understood that certain foods contain substances vital to human life. The ancient Egyptians recognized that night blindness was cured by eating liver. In the 1700s, seagoing men found that lime juice prevented scurvy – the aches, skin rashes and loss of teeth from painful gum disease that occurred when men attempted to live for months without fresh food. When the nature of food’s magic yielded to chemical analysis, scientists found complex molecules with many active forms that acted as co-factors or triggers in energy-producing chemical reactions in all cells of the body. They were also involved in cell maintenance and reproduction.

Naming the magic

Chemists named the indispensible compounds vitamins (vita: root word for life; amine: a chemical group containing nitrogen, which early studies suggested all vitamins contained) and tagged them with letters as well as chemical names (see list below). Vitamins F – K eventually became part of the large Vitamin B complex group, and some vitamins were downgraded to “vital nutrients.”  Synthetic vitamins appeared on store shelves, joining age-old remedies like cod liver oil, yeast and wheat germ.  But even in our times, the best source of vitamins remains the whole foods in which nature embeds them with other factors that we may not yet recognize as important.

Water soluble vitamins

The B vitamins and Vitamin C dissolve in water. They aren’t stored in the body and can be lost or inactivated by cooking. These water-soluble vitamins find their way to their target cells, get used, recycled a bit, and then find their way out of the body in the urine. They need to be eaten on a daily basis.  You cannot overdose on B vitamins in food, but very high doses of B vitamin pills can damage the nerves.

Fat soluble vitamins

Fat-soluble vitamins (A, D, E and K) accumulate in liver and fat tissue, ready to be used when necessary, but damaging if too much is stored.  Some Arctic explorers died of brain swelling from consuming polar bear liver, very high in Vitamin A. Too many carrots (source of carotenes, or pre-Vitamin A) cause yellow skin. Too much Vitamin D raises blood calcium levels, producing weakness, lethargy and kidney stones.  Vitamin K can interfere with Coumadin, a medicine used to prevent blood clotting, so patients are cautioned to eat only small amounts of very flavorful greens like Kale and collards.

If you are not alcoholic or malnourished from serious illness, if you live in a western countries where vitamin fortification (enrichment) of common foods is the routine, if you eat well-balanced meals drawing fresh food from plant and animal sources, if you are meeting your energy needs and not trying to lose weight by restricting calories, and if you get enough sun exposure, you do not need any vitamin pills. Vitamins are best absorbed from real food.

Vitamin supplements?

In our current eating culture, however, a couple of vitamins do warrant concern. Folate (Vitamin B9) consumption, vital to cell replacement, is inadequate when fruits and vegetables are not chosen or hard to come by.  Vitamin D deficiency, which became rare when fortification of milk began, is again on the rise, producing rickets (malformed bones) in children, weakened bones in adults, and weakened immune systems in all age groups. Cholesterol phobia makes people avoid good Vitamin D sources like whole milk and egg yolks.  Sun exposure of head and arms for just 15 minutes 2 or 3 times a week makes enough Vitamin D in skin to our needs, but effective sunscreens and lack of outdoor activity have put serious dents in sun exposure.

What about Vitamin C, the wonder vitamin? Most plants and animals make it. We do not.  Linus Pauling, Nobel prize-winning chemist, speculated that our intake should be much higher than the small amount required to prevent scurvy. Apes, who’ve also lost the ability to make Vitamin C, consume 10 -20 times as much as we do. Goats, who make Vitamin C in huge quantities, make even more when stressed.  Does Vitamin C help prevent colds, strengthen our connective tissue, and get used up faster in times of physical stress? Maybe.  We just don’t know. But in the meantime, large doses, up to several thousand milligrams per day, appear to do no harm. (Smokers do need extra C.)

Take advice with a grain of salt

What are we to think of all the articles we see extolling the virtues of this vitamin or that in preventing this disease or that? Be wary of these words: suggests, indicates, may be, could prevent. If any of the putative effects were as clear as our emergency room patient’s revival, or the salvaging of sailors’ gums and teeth, or the cure of the Egyptians’ night vision, we would not be using tentative words. Keep your focus on a fresh food diet that excludes no food group, and on the physical activity that enables you to eat enough food to get everything you need without getting fat. Take Vitamin C if you want to, and add a multivitamin from a reputable company if you are dieting or restricting your diet in any way, or don’t like vegetables and fruit.

 

 

 

 

Major Vitamins and Some Food Sources

 

Vitamin name

Chemical name

(RDA) Recommended daily allowance
(male, age    19–70)

Animal Source

Plant Source
Vitamin A (retinol, retinoids
and carotenoids)		 900 µg

(micrograms)

 Beef and chicken liver*

Whole milk, eggs, cheese

 Carrots, spinach, yellow vegetables and fruits
Vitamin B1 Thiamine 1.2 mg

(milligrams)

 Pork*, lean meats, fish Brewer’s yeast*, wheat germ*, whole grains

Enriched grains, legumes, nuts
Vitamin B Riboflavin 1.3 mg Eggs, lean meats, milk Brewer’s yeast*, cereals, nuts, leafy greens
Vitamin B3 Niacin 16.0 mg Lean meats, poultry, fish, eggs Beets, Brewer’s yeast*, peanuts, other nuts, sunflower seeds, green leafy vegetables, coffee, tea
Vitamin B5 Pantothenic acid 5.0 mg Calf’s liver*, eggs, yogurt Brewer’s yeast*, whole grains,sunflower seeds, mushrooms, squash, cauliflower, broccoli
Vitamin B6 Pyridoxine 1.3-1.7 mg Liver, egg yolks, poultry, fish Wheat germ, whole grains, peanuts, walnuts, bananas, avocados
Vitamin B7 Biotin 30.0 µg Eggs yolk, liver Brewer’s yeast, wheat bran cauliflower, avocado
Vitamin B9 Folic acid 400 µg Beef liver*, egg yolk Fortified cereals*, leafy green vegetables, citrus fruits
Vitamin B12 Cyanocobalamin 2.4 µg Meat, eggs, dairy products, shellfish, salmon Fortified plant milks and cereals only. No natural plant sources.
Vitamin C Ascorbic acid 90.0 mg   Citrus fruits*, tomatoes, berries, green and red peppers, broccoli, spinach
Vitamin D Ergocalciferol and
Cholecalciferol		 5.0 µg-10 µg Dairy products, salmon, tuna Fortified cereals
Vitamin E Tocopherol and
Tocotrienol		 15.0 mg   Wheat germ oil*, almonds*, hazelnuts,sunflower seeds and oil, safflower oil
Vitamin K Naphthquinone 120 µg   Broccoli*, Kale*, Swiss chard*, soybean oil*, canola oil, olive oil

*excellent source

Posted by medical plaintalk

Physician turned medical writer.

Iodine: An Unfinished Story

In these days of high tech medicine it is easy to forget that some of the most effective and efficient health interventions are simple and cheap. One example is the addition of iodine to salt, an idea which began in the early 1900s with experimental trials in schoolchildren living in what was then known as the “goiter belt” of the USA. In that region surrounding the Great Lakes, many children developed enlarged thyroid glands called goiters.  A goiter is a sign of iodine deficiency.  So successful were the trials of iodine-supplemented diets that, by the 1930s, 90% of residents of the Great Lakes region used iodized salt and goiter rates in the region had plummeted.  Now, 70% of the world’s population uses iodized salt.

Iodine as an essential element

When iodine is in short supply, thyroid glands grow large in an attempt to harvest as much of the vital element as possible from the blood.  Iodine is necessary for making thyroid hormone and thyroid hormone is crucial for normal development and metabolism.  Pregnant women who have  low iodine levels and insufficient thyroid hormone often miscarry their babies or produce babies who are deaf, mentally-retarded  and stunted in growth.  In children and adults, iodine and thyroid hormone deficiencies cause fatigue, weight gain, lowered IQ levels, mental apathy and numerous metabolic abnormalities.  Regular intake of iodine is a simple preventive measure for a host of serious problems.

Unequal distribution

Iodine exists in an inorganic form in soil and water and makes its way into the plants and animals that we consume by combining with larger carbon-containing molecules.  In its inorganic form, iodine is a water-soluble salt which washes out of soil easily, especially in areas where the land is rocky and exposed. Where soil is iodine deficient, so are crops, unless supplemented with iodine containing fertilizers.  In contrast to its variable presence in soil, iodine is much more uniformly distributed in salt water seas.  Algae, kelp and other seawater plants, as well as saltwater fish and shell fish are the most reliable natural sources of dietary iodine, while iodine concentrations in land based plants depend on the amount of iodine in soil that supports them.  Terrestrial animals supply iodine proportional to the iodine in their food sources. Egg yolks are a good iodine source, because, like people, chickens develop goiters, and chicken feed is supplemented with iodine. Dairy products are also good sources. Cattle feed was originally supplemented with iodine to prevent hoof rot, and and because of the supplemented feed, iodine is secreted in the milk the cows produce.

Iodine and breast tissue

Milk contains iodine because mammary gland tissue, like thyroid gland tissue, accumulates iodine. The fact that iodine is found in human breast tissue, where it has no known function, has prompted studies of the element’s relationship to breast health.  Japanese women have low rates of breast cancer and fibrocystic breast disease compared to American women, and their regular iodine consumption via seaweed is high, perhaps 25x higher than the recommended daily iodine consumption in the US. Studies on the treatment of fibrocystic breast disease with iodine supplements have been promising but so far a direct relationship between breast disease and iodine consumption has not been proven.

Iodine supplementation?

Even if high dietary iodine content has something to do with low breast cancer rates among Japanese women, translating this information to attempts to prevent breast cancer is not a straightforward task. While it is clear that iodine supplementation prevents goiter, hypothyroidism and cognitive impairment, it is also clear that increasing iodine intake is not risk free, particularly in people who are accustomed to low levels of dietary iodine.  The thyroid gland, when faced with insufficient iodine in the blood, becomes a ruthless scavenger, extracting every last iodine molecule it can find. When iodine levels in the blood suddenly increase because of supplementary iodine intake, some thyroid glands will actually grow in size, pump out excessive thyroid hormone and even develop cancerous nodules. It may be that Japanese women can tolerate high amounts of iodine because it has never been in short supply for them. Caution and careful follow-up are always advisable when supplementing the diet with iodine in the form of tablets, drops or multivitamins.

Dietary iodine in the age of dietary angst

Obtaining enough iodine through the diet should be possible in almost all circumstances, especially because of the wisdom of public health policies regarding iodine.  Nevertheless, some eating trends in health in the closing decades of the 20thC have again raised public health concerns about iodine intake.   Assessments of body iodine content are made by measuring urinary iodine levels, since the body extracts as much iodine as it needs and excretes the rest in urine. But individual measurements are so variable that averages of all people tested are used to estimate the iodine status in a given geographic area.  Between 1971 and 2001, American iodine intake dropped dramatically then leveled off at half of the 1971 levels.

What happened over the last few decades?   Americans began getting much more of their salt in the form of the un-iodized salt in processed foods. Many people began avoiding salt altogether, some quite unnecessarily. Sea salt appeared on the grocery store shelves as part of the natural and organic food trends.   It is also possible that the 1971 levels of iodine consumption were artificially high. Studies in the 1970s showed that iodine-containing sanitizers were raising iodine levels in cows’ milk. Practices changed and milk iodine levels returned to normal.   Between the 1960s and 1980s, iodine was used in dough making and bread supplied 25% of the iodine consumed during that period.*  Perhaps the baseline measurements of iodine intake in the early 1970s were unnecessarily high. Perhaps intakes in 2001 and since  are adequate, at least to prevent goiters from developing. But the fact that Japanese people ingest far higher levels of iodine from whole food sources without ill effect suggests that we can tolerate more. Stay tuned.

 

*Note: Iodine in the Nuclear Age

In the wake of the atmospheric nuclear testing period, the government mandated the use of iodine containing oxidizing agents for dough conditioning in commercial baking. The iodine in the bread  competed  in the diet for uptake into the thyroid gland with radioactive iodine isotopes generated in  the wake of atmospheric nuclear testing. Saturating the thyroid gland with normal iodine is standard practice when radioactive iodine in the atmosphere  is a threat, as it was after the Chernobyl disaster. Taken within 8 hours after, or 48 hours prior to a nuclear disaster, iodine can prevent accumulation of radioactive iodine in the thyroid gland and thus prevent radiation damage to the gland. Pills to be taken in the event of a nuclear catastrophe are simply potassium iodide.

Posted by medical plaintalk

Physician turned medical writer.
No more posts.