Richard G. Petty, MD

Another Nail in the Coffin of BMI


In August I outlined some of our reasons for believing that the most common measure of overweight and obesity – the body mass index (BMI) – can be very misleading and should probably be abandoned, or at least consigned to the back burner.

A team at the Hammersmith Hospital in London led by Professor Jimmy Bell has been using a novel type of MRI scan to locate the distribution of fat in the body. The problem is that 40% of the population has “bad” fat around some of their internal organs including the heart, liver or pancreas, even though many appear thin. So even though they may look slim, they may still be at risk of conditions like insulin resistance, diabetes and hypertension because of this hidden fat.

As we have said before, from a health perspective, it is the distribution of fat that is all important, rather than just the amount of it. This study confirms what metabolic physicians have been saying for years: BMI gives you the wrong idea about how much fat you have.

Once you know about the distribution of your fat, we can design precise lifestyle changes to work on it. As an example, the strategies that we use for overall weight management are not the same as the strategies that we use for reducing intra-abdominal fat. There are very good physiological reasons why diet does little to reduce the fat around organs. It is there to provide fuel during exercise, so specific exercises are the way to rid yourself of this internal fat.

At the moment there are very few centers that can do this kind of scanning, but with the growing evidence of its importance, that is likely to change. In the meantime, be aware that aerobic exercise and strength training, particularly if it involves the large muscles of the back trunk and lower limbs is the quickest way to rid yourself of these dangerous fat deposits.

Fat in itself is essential for normal health, but fat in the wrong places can be a killer. And BMI tells you nothing about the fat lurking in the hidden parts of your anatomy.

Hidden Harbingers of Weight: Salt Intake and Obesity

In Healing, Meaning and Purpose, I discuss some of the evidence for four previously little recognized causes of obesity:

  1. Stress
  2. Salt intake
  3. Pesticides
  4. Viruses

Each of these has been widely discussed in the professional literature, but little has percolated out into the general population except in advertisements for agents like Cortislim. I remain skeptical about these products. Tinkering with just one of the 260 hormones and neurotransmitters implicated in the control of weight is unlikely to be crowned with success. And their ingredients may also have the potential for causing problems. Recent advertisements have also mentioned that one of these products may elevate mood. Sad to say, in the last year we have seen two people who developed manic symptoms after taking one of the supplements. We are urging colleagues to see if there are any other cases, or whether these two were just coincidental.

I recently mentioned some of the evidence for viruses as a cause of weight gain.

Now a new publication from the Universities of Helsinki and Kuopio is out in this month’s journal Progress in Cardiovascular Diseases, that provides powerful support for the salt hypothesis.

The researchers report that an average 30-35 % reduction in salt intake during 30 years in Finland was associated with an extraordinary 75 % to 80 % decrease in both stroke and coronary heart disease mortality in the population under 65 years. During the same period the life expectancy of both male and female Finns increased by 6 to 7 years.

As expected, reducing salt intake has a beneficial effect on blood pressure.

But in my view the most interesting finding of the study is the close link between salt intake and obesity.

As bartenders, pub landlords and tavern owners have known since the beginning of time, increasing a person’s intake of sodium produces a progressive increase in thirst. (You didn’t think that those peanuts on the bar were put there out of the goodness of the establishment’s heart did you??!)

The progressive increase in the average intake of salt explains the observed increase in the intake of sugar-containing beverages which, in turn, has caused a marked net increase in the intake of calories during the same period in the United States.

Here is an extraordinary statistic: Between 1977 and 2001, energy intake from sweetened beverages increased on the average by 135 % in the United States. During the same period, the energy intake from milk was reduced by 38 %. The net effect on energy intake was a 278 kcal increase per person a day. The American Heart Association has estimated that, to burn the average increase of 278 kcal a day and avoid the development or worsening of obesity, each American should now walk or vacuum 1 hour 10 minutes more every day than in 1977. As we all know, that has not happened.

In the decade from 1976-1980 to 1988-1994 the overall prevalence of obesity increased 61 % among men and 52 % among women. During 1999 to 2002, the prevalence of obesity was 120 % higher among men and 99 % higher among women as compared with the 1976 to 1980 figures. The increased intake of salt, through induction of thirst with increased intake of high-energy beverages has clearly made a significant contribution to the increase of obesity in the United States.

It is also of note that until 1983 the use of salt did not change or even showed a continuous decreasing trend in the United States. The prevalence of obesity was relatively low and remained essentially unchanged from early 1960s to early 1980s.

This new study suggests that a comprehensive reduction in salt intake, which would reduce the intake of high-energy beverages, would be a potentially powerful means in the so far failed attempts to combat obesity in industrialized societies.

There is now conclusive population-wide evidence that indicates that we could achieve powerful beneficial health effects simply by reducing our overall salt intake. These benefits include a decrease in obesity.

As an aside, the population-wide long-term experience from Finland indicated that a remarkable decrease in the salt intake has not caused any adverse effects.

A number of years ago we were engaged in some experiments in which we replaced regular table salt – sodium chloride – with potassium chloride. For the first three weeks food seemed rather tasteless. But then we all suddenly discovered a new universe of flavors that had previously been hidden under a thick coating of salt. So a dietary change does have a temporary effect on your taste buds.

Although the paper doesn’t say so, there is also some data that salt may itself increase cortisol release.

The bottom line?

We now have clear, empirical data to support three out of the four points that I made in Healing, Meaning and Purpose, and there is some less robust data for the fourth.

I urge you to try gradually to reduce your personal intake or salt, and to encourage your family and friends to do the same. I mentioned that food may initially seem a little less flavorful, but then things change rapidly and for the better.

And your body will love you for the change!

Update on Pramipexole

I have mentioned pramipexole before. In the United States it is approved for the treatment of the signs and symptoms of idiopathic Parkinson’s disease.

I’m always on the look out for medicines that can be part of a package of healthcare, and we need to learn both the pros and cons of new medicines. This looks to be a medicine that can be incorporated into Integrated Medicine. And before you ask, I have no links at all with the manufacturer, Boehringer Ingelheim.

There have been a number of interesting papers presented at the 10th International Congress of Parkinson’s Disease and Movement Disorders in Kyoto, Japan this week.

New data presented have shown that people taking pramipexole (Mirapexin®/ Sifrol®) can experience significant improvements in a broad range of symptoms associated with Restless Legs Syndrome (RLS). 

In all studies presented at the meeting, people taking pramipexole reported clinically meaningful improvements in both their night and day-time symptoms, as measured on the International Restless Legs Scale (IRLS). The IRLS measures several aspects of the condition, ranging from discomfort, the need to move around, relief by moving around and then more specific RLS symptoms such as sleep disturbance, day-time tiredness, mood disorder, as well as addressing overall severity, weekly frequency, daily severity, and impact on daily activities.

One of the big problems in the treatment of RLS is that people who have it frequently have other problems as well, such as hypertension, arthritis, gastroesophageal reflux disease, depression, anxiety, and diabetes. So it is essential that the physical component of treatment should not cause any deterioration in associated illnesses. One of the papers presented in Kyoto indicated that pramipexole could be used in people with RLS who are also taking an array of other medicines. That claim is going to have to be checked by the FDA, but the data look very encouraging.

Still, when using medications, there’s no such thing as a free lunch: The most commonly reported adverse reactions in clinical trials for RLS were nausea, headache, and tiredness.

In people with Parkinson’s disease, pramipexole may cause them to fall asleep without any warning, even while doing normal daily activities such as driving. This is obviously very serious, and before the medicine gets an RLS indication in the USA, the FDA will really check this out in great detail. When taking pramipexole hallucinations have been known to occur and sometimes patients may feel dizzy, sweaty or nauseated upon standing up. In Parkinson’s disease, there is also a warning that as with many other medicines used to treat it, including pramipexole may be associated with impulse control disorders/compulsive behaviors.

So we need to keep an eye on safety, but so far the data is very encouraging, and we may soon have something else to add to an integrated treatment program for people with RLS.

___________

Here’s a P.S. On November 10th, 2006, pramipexole was approved for use in RLS by the FDA. Here’s the announcement:

Ingelheim/Germany, 10 November 2006 – Boehringer Ingelheim announced today that the U.S. Food and Drug Administration (FDA) has approved pramipexole, a non-ergot dopamine agonist, for the treatment of moderate to severe primary Restless Legs Syndrome (RLS).1 This is an important milestone for pramipexole (Mirapexin® / Sifrol® / Mirapex®), which was already approved throughout the European Union in April 2006 for this second indication.

Handedness and Immunity

In 1982, one of my mentors, the late Norman Geschwind, and two colleagues – Al Galaburda and Peter Behan – proposed an extraordinary hypothesis. It was that the levels of testosterone to which a baby is exposed before birth influence the development of both the cerebral and immune systems. According to this theory, high levels of testosterone result in greater incidences of left-handedness, deviations from the standard distribution of cerebral functions and increased autoimmune dysfunction. If the theory is right, then male brains should mature later than female brains, and the left hemisphere should mature later than the right.

It is certainly true that if a boy gets a head injury or infection involving the brain, he is less likely to recover than would a girl, and boys are far more likely to have some types of neurodevelopmental problems like dyslexia.

For a while it seemed as if there was also a strong association between left-handedness and certain types of allergy, and also with inflammatory bowel disease. This association with immunity also seemed to be present in mice: those who had left paw preference had more reactive immune systems, and they were thought to be more likely to produce auto-antibodies, suggesting that the central nervous system was involved in the genesis of some autoimmune diseases. Over the years the data has become less clear-cut, but the idea of an association between anomalous cerebral asymmetry and autoimmune disease never completely went away.

Recent data has again found an association between inflammatory bowel disease and laterality. And left-handers really do have more autoimmune disease.

The Geschwind-Galaburda hypothesis proposes that there should be a four-way association among neurodevelopmental disorders, special talents, non-right handedness, and immune disorders. In a huge study of 11,578 children, less than 1% had all four.

So where does this leave us?

The original theory was half right:

  1. There is indeed a link between testosterone and early brain development
  2. People who are left-handed or have a strong tendency toward left-handedness do seem to be at slightly increased risk of several autoimmune conditions
  3. People who are left-handed or have a strong tendency toward left-handedness may have a slightly increased risk of high blood pressure, asthma and migraine
  4. People who are left-handed or have mixed handedness are more likely to excel in certain disciplines: creative arts, music, computer programming and mathematics. What we don’t know is whether people with these special skills are more likely to have autoimmune diseases
  5. Amongst very successful tennis players,  there are far more left-handers than would be predicted by chance. This supports the idea that support the notion that left-handed people have neurological advantages in performing certain tasks, such as visuospatial visuomotor cognitive tasks.

I was reminded of the way in which Nature seems to like to balance things out a bit: with some notable and famous exceptions, many successful athletes have not done so well academically and many academics would be unlikely to survive on the plains of Africa. Only some of these differences can be explained in terms of early direction and encouragement in school or while growing up: it seems that most of us cannot hope to become the kind of superman that Nietzsche used to dream about.

Perhaps it’s a way of stopping us from getting too full of ourselves.

Medicine and the Transformation of Illness

Something important has been happening in the medical field over the last century. And like most important concepts, once I mention it, everyone says, “Oh, that’s obvious.” Yet I have seen little discussion of it except in an occasional book or speculative paper.

The concept is this: modern medicine has been transforming the nature of illness in far-reaching ways. There are many illnesses that once were fatal, and which have now been transformed into chronic problems. Yet most conventional health care providers are still wedded to the short-term resolution of symptoms.

Let me give you three examples:

  1. The first is diabetes mellitus. There are two main types, and at least ten subtypes. Type 1 diabetes is what used to be known as juvenile onset diabetes or insulin-dependent diabetes. It usually comes on in childhood or adolescence, is associated with severe damage to the beta cells in the pancreas that produce insulin. People with this problem usually become very sick very quickly and need insulin to keep them alive. Until 1922, when the first patient was treated with insulin derived from cows, the illness was usually fatal. Insulin transformed it into a chronic illness. People were kept alive, but now we saw the emergence of diabetic eye disease (cataracts and retinopathy), disease of the blood vessels supplying the limbs, heart and kidneys, kidney failure, infections and many other chronic problems. In 1935 Sir Harold Himsworth, the father of a friend of mine, identified a second type of diabetes. He published a classic paper on his discovery of insulin resistance in 1936. This is what is now known as Type 2 diabetes, and used to be called maturity onset diabetes. This is a more chronic illness, but carries many of the same complications. The point about these two types of diabetes is not just that they have disturbances of glucose and lipid metabolism. That on its own matters little. It is the long-term consequences of the elevated glucose and lipids that causes all the problems.
  2. The second is hypertension. Again, this often used to be a fatal illness. Until the invention of the sphygmomanometer most people did not know that they had high blood pressure, and most often would die of strokes. Hypertension is now also a chronic illness. The problem is not the blood pressure itself, but the long-term consequences of an elevated blood pressure. That is why most physicians are now trying to prevent the damage to the heart, eyes and kidneys, instead of just focusing on the blood pressure numbers themselves.
  3. The third is Lyme disease. This is a bacterial illness that is acquired by being bitten by a tick. It is said to be the fastest growing infectious disease in the United States, primarily because we are spending more time venturing into the wilderness, and the deer population – a major carrier of the tick – is increasing in most Eastern states. Lyme disease can make people very ill. We identify acute and chronic types. The acute can usually be treated if identified quickly and if the correct treatment is given. But sometimes identification can be very difficult, and inadequate or even inappropriate treatment may lead to the chronic form. We have even seen people who have been treated exactly as the experts say, but have still developed the chronic form of Lyme disease. The biggest problem with Lyme disease is that it is a great masquerader: it can look like so many other illnesses, from multiple sclerosis and rheumatoid arthritis to chronic fatigue syndrome and syphilis.

We could pick out other examples. I have mentioned some of the problems of thinking that attention deficit disorder is just a problem with getting good grades in school. When in reality the problem is that inadequately treated ADD is associated with a range of long-term problems that occur outside of school hours.

For many years now some practitioners have been warning about the long-term consequences of symptomatic treatment alone. One of the most eloquent critics of this way of treating people is the Greek homeopath and teacher George Vithoulkas. I like and respect George, but he takes a militant view, saying that conventional treatment simply suppresses illnesses, rather than treating them. His solution is to use homeopathy for everything. He is a genius and also a natural healer, so he can probably get away with that. Most of us cannot.

So the fundamental tenets of Integrated Medicine include medical treatment to deal with the acute problem, but a combination of approaches to prevent the problem from becoming chronic. Or if it has become chronic, then how to change its course over time.

As I’ve said before: Combinations are Key. Not randomly giving an antibiotic as well as a homepoathic remedy, but precisely tailoring the combination to the individual.

Shock Waves and Diabetes

A psychiatrist friend once called me to say that he knew that he had to change his job. He was in the second year of his Freudian training analysis, and as he was driving to work he experienced a severe pain in the back. He told me that it felt as if someone had put a knife in his back. This, he told me, was a psychosomatic reflection of the mean back stabbing environment in which he was working. “Tell me more about the pain,” I said. “Just like a knife,” he said, “it’s the most obvious example of my body telling me what’s going on here.” I suggested that he should come over for me to give him a physical check up, but he was having none of it.

The following day he passed a large kidney stone.

It’s important to listen to your body, and to try and understand its message. It’s also important to respect every aspect of your being: physical, psychological, social, subtle and spiritual. A physical pain may be telling you about something in your environment or it may just be telling you that there’s something wrong with your body. Sigmund Freud once famously remarked that “Sometimes a cigar is just a cigar.”

I was reminded of this story as I was reviewing a new report about an association between the use of sound waves – lithotripsy – to shatter kidney stones and the eventual development of diabetes. Approximately 10 percent of men and 5 percent of women under the age of 70 will experience a kidney stone.

Surgery for kidney stones used to be horribly traumatic. As a very young student and junior doctor I assisted in more than one operation to remove them. The invention of the lithotripter – a device that uses ultrasound to break up stones, so that they can be passed out of the body – was a big advance. Though the treatment itself is far from being painless, it is much better than major surgery, It is a shame to learn that the treatment is not as innocuous as we thought. This is important, because about 1 million people in the United States have had shock wave lithotripsy (SWL).

In a study published in the May issue of the Journal of Urology, researchers at the Mayo Clinic followed up on a group of 630 patients who had been treated with SWL in 1985. The Mayo was one of the first centers to use the technique, the hospital keeps wonderful records, and so it was one of the few places in the world where it was possible to follow people 19 years after treatment.

Almost 60 percent of the patients responded to a questionnaire and were matched to an equal number of patients whose kidney stones had been treated by some other method. Among the SWL group, 16.8 percent had developed diabetes, compared with 6.7 percent of the control group, and 36.4 percent had high blood pressure compared with 27.9 percent of the control group. According to the study, the development of hypertension was related to the treatment of stones in both kidneys, while the onset of diabetes bore a relationship to the number of shocks administered and the intensity of the treatment.

This makes sense: the kidneys are key controllers of blood pressure, and it has long been known that stones, inflammation, infection or vascular disease in the kidneys can cause elevated blood pressure. Perhaps the treatment scars the kidneys. And it is not surprising that sound waves powerful enough to shatter a stone might also cause damage to the tissues through which they are passing; which include the pancreas.

These findings will need to be replicated, particularly with newer model lithotripters. But even before that, I’m sure that the criteria for gets the treatment will be modified, and it will also be necessary to re-think how the treatment is done. As an example, instead of shooting one powerful burst of sound waves at the stone, it may be necessary to fire several low intensity burst from different directions that all crisscross in the vicinity of the stone.

For now, if you are one of the unlucky ones who gets a kidney stone, discuss this new research with your doctor before having lithotripsy. And if you have access to a good acupuncturist, naturopath or homeopath, ask them if they have had any success in treating kidney stones, and if “Yes,” whether they would be prepared to work with your physician to help you.

Thrifty Genes, Thrifty Bodies and the Barker Hypothesis

“They have sown the wind, and they shall reap the whirlwind.”
–The Bible (Hosea, 8:7)

In 1962, a geneticist named James Neel first proposed a “thrifty gene” theory to explain why 60% of adult Pima Indians living in the United States have diabetes, and 95% are overweight. Neel’s theory was that populations like the Pimas, that have for millennia relied on farming, hunting and fishing for food, would experience alternating periods of feast and famine. Neel hypothesized that in order to adapt to these extreme changes in caloric needs, people developed a “thrifty gene” that allowed them to store fat during times of plenty so that they would not starve during times of famine.

A similar theory was advanced to explain the high rates of diabetes in people from the Indian subcontinent, once they are exposed to plentiful supplies of food. These was traced by the great Diaspora from central Asia at the end of the last age, when the ancestors of modern Indians and Pakistanis made the great trek through modern Afghanistan into the Indus valley. A journey that had been impossible at the height of the Ice Age and which was still difficult. The idea was that people who could quickly lay down a lot of intra-abdominal fat would have a huge survival advantage.

This is an attractive hypothesis, but here have always been some problems with it:

  1. The gene or genes would have to be able to work with the environment: the Pimas of Mexico and people living in rural India do not have the high rates of diabetes and obesity
  2. Despite looking for over 40 years, no such gene has yet been found
  3. If the thrifty gene is so advantageous, why doesn’t everyone have it?
  4. Until recently, famines were rare and usually occurred every 100-150 years. As John Speakman has pointed out that would mean that most human populations have experienced at most 100 famine events in the course of their evolutionary history
  5. Famines do increase mortality but only in about 10% of the population
  6. In famines most people die of disease rather than starvation, and the worst affected are the young. Having a “thrifty gene” would not help them survive starvation OR disease
  7. Simple genetic models would suggest that famines would not provide enough selective advantage and there has not been enough time for a “thrifty gene” to have penetrated the population

There could yet be some complex genetic model involving “reserve” genes that appear when needed, or some epigenetic inheritance, but we have no evidence for that either.

A second concept is gaining a lot of traction. It is what is known as the “Thrifty phenotype,” and is part of a larger theory called the “Barker Hypothesis.” I’m going to stick my neck out, and predict that David Barker may receive the Nobel Prize in medicine for his discoveries. They are that important.

Essentially the Barker Hypothesis suggests that in addition to genetic, epigenetic and environmental factors in disease, there is another, and that is the intrauterine environment. The idea is that if a mother is malnourished, she can modify the development of her unborn child. From an evolutionary perspective, her body is preparing the unborn child to survive in an environment where food is in chronic short supply, resulting in the “Thrifty phenotype:” smaller body size, lower metabolic rate and a propensity to be less active.

The problem is this. If you are born with the thrifty phenotype and actually grow up in an affluent environment, you are more likely to develop obesity, diabetes and vascular disease later in life. If true – and virtually all the evidence suggest that it is – then it has serious implications for countries that are transitioning from sparse to better nutrition, and may have contributed to some of our current health problems. Many of us were born to mothers who had poor nutrition, either because of the Great Depression, the Second World War, poverty, or just plain poor information about good nutrition during pregnancy. And now we are reaping the whirlwind.

The hypothesis has become sophisticated. If you are born small or premature, then your liver and kidneys may not have completed their final growth spurt, which might predispose you to metabolic problems and hypertension.

The story of how this all came to light would be worthy of Sherlock Holmes himself.

English counties used to have people who were responsible for providing midwifery services. In the county of Buckinghamshire a single midwife collected data for almost thirty years. Information about the mother, the length and weight of the baby and the weight of the placenta. Information that would be impossible to collect these days. Some civil libertarian somewhere would probably dream up some way of hiding this enormously important information.

David Barker discovered these extraordinarily good records, and then set about finding the adults that these babies had become. And what he found has changed medicine: babies who had small placentas – a good measure of being small or premature – were more likely to develop obesity, diabetes or hypertension as adults. Then he and others turned their attention to other early physical characteristics and found correlations with health later in life. The highest risk of coronary heart disease was seen amongst people who were born small and became heavier during childhood.

The practical implications?

Find out your own birth weight and anything else that you can about your early development.

If you were a very large baby (bigger than nine and a half pounds), it implies that your mother may perhaps have had a metabolic problem. If you were small (less than five and a half pounds), then you should get the regular health checks that we recommend for anyone in a “high risk” group.

BMI R.I.P.

For experts in metabolism, we have long worried about the over-emphasis on the use of body mass index (BMI) as the arbiter of a "healthy" weight. It is one of those measurements that is in some senses too easy, and the results are deceiving. I regularly see people claim that a certain BMI will "predict" the risk that someone will develop cardiovascular disease or diabetes. The truth is very diferent.

There are two ways to calculate your BMI:
1. Metric system – Kilograms and Metres
[Your weight] divided by [Your height squared]

2. Imperial System – Pounds and Inches
[You weight] divided by [Your height squared] times 703.5

A person is said to be healthy if his or her BMI is between 18.5 and 24.9.

The trouble with this is that the calculation lumps together fat and muscle: a muscular six foot tall football player weighing 300 pounds and with 3% body fat, would have an "unhealthy" BMI of 26.3. That is clearly absurd, and one of the reasons that most experts use BMI only as one part of an evaluation of health.

Our scepticism has been confirmed by an important study from the Mayo Clinic in Rochester, Minnesota, and published in this week’s issue of the medical journal The Lancet.

The researchers looked at 40 studies involving 250,152 patients. Their analysis revealed that people with a BMI of 30-35 were at lower risk of cardiovascular disease than those whose BMI was below 20.

BMI does not correlate well with fat. A better way to distinguish between fat and muscle is to take a cross-sectional view of the abdomen, and to focus on the waist-hip ratio.

A separate study by researchers at the London School of Hygiene and Tropical Medicine of 14,833 people over the age of 75 was published in the American Journal of Clinical Nutrition. They also came to the conclusion that BMI is a poor indicator of health in both men and women in this age group. These researchers also agreed that waste-hip ratio was a better indicator of mortality risk.

This is all music to my ears. For almost three decades we have been teaching about the importance of  different stores of fat and the limitations of the BMI calculation. It has been known since the 1940s that gaining weight on the hips, or developing "lover’s handles" are only very weak predictors of diabetes and vascular disease: it is the intra-abdominal fat that is the problem.

There are particular problems with using BMI in the elderly and in some ethnic groups, especially people from the Indian sub-continent and Japan.

The bottom line?

BMI is misleading, and in some age groups and races, grossly misleading.

Much better to use weight and waist-hip ratio.

And BMI only if there is a space on the medical forms where they still need to have it filled in.

 

How Many Angels Can Dance on the Head of a Needle? Moving Beyond the Metabolic Syndrome

I have written a great deal both on this blog and in scholarly articles, about insulin resistance and the insulin resistance and metabolic syndromes.

You will have noticed that I’ve always used the term insulin resistance syndrome.

This is not a matter of semantics. For years now I’ve been worried about the splitting that’s been going on in the field: we currently have six sets of definitions of the metabolic syndrome. And apart from the fun of going to all those conferences in exotic parts of the world, you have to ask what’s been achieved by these ever more divisive attempts to “define” the medical consequences of insulin resistance.

The American Diabetes Association has begun to promote the concept of “cardiometabolic risk.” The Association has established a national Cardiometabolic Risk Initiative (CMRI) to stress the association between diabetes, heart disease and stroke. The idea of introducing this umbrella term is to help people better understand and manage all diabetes and cardiovascular risk factors, and to side-step some of the controversy surrounding the definition of insulin resistance or metabolic syndrome and which cluster of variables are in and out.

A new Cardiometabolic Risk (CMR) Calculator to help us evaluate an individual’s risk of diabetes or vascular disease should be available by the end of the year.
The formula already includes factors such as:
1.    Body mass index
2.    Waist circumference ratio
3.    Fasting plasma glucose
4.    HDL-cholesterol
5.    LDL-cholesterol
6.    Triglycerides
7.    Apolipoprotein B
8.    Blood pressure
9.    C-reactive protein
10.  Age
11.  Sex
12.  Race/ethnic origin
13.  Family history
14.  Tobacco use

Part of the reason for this new initiative is the discovery that pre-diabetes, or impaired fasting glucose, where plasma glucose levels are 100-125 mg/dl, is associated with a high prevalence of cardiovascular disease risk factors such as obesity, hypertension and dyslipidemias.

The person who first proposed the insulin resistance syndrome, a.k.a. syndrome X, a.k.a. metabolic syndrome, is Gerald Reaven who first recognized the syndrome in a landmark paper in 1988. He recently gave a lecture entitled; “Insulin Resistance Versus Metabolic Syndrome: Different Names, Different Concepts, Different Goals.” I am in complete agreement with his basic proposition, which is that insulin resistance explains the clustering of all of the components that make up the metabolic syndrome. So Gerry’s position is that there’s no point in trying to make a diagnosis of metabolic syndrome: everything is due to insulin resistance.

So instead of wasting time and resources in trying to diagnose metabolic syndrome, it is much better to understand the pathophysiology: what is going on at the molecular level, how these processes produce risk factors, and whether we can predict others. We should identify and treat each of the underlying processes and the complications of insulin resistance. If we are going to have a syndrome, it should be called insulin resistance syndrome.

And let’s stop these academic debates and get on with the job at hand: there is a 600% variation in peoples’ ability to have insulin transport glucose into cells. More than half the US population is destined to develop at least some degree of insulin resistance, so we need to look for better ways to identify people who have it, and to apply the principles of integrated medicine to keeping them healthy.

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A New Warning from the FDA about Some “Sexual Enhancers”

On Wednesday of this week the Food and Drug Administration issued a warning to consumers not to purchase or consume Zimaxx, Libidus, Neophase, Nasutra, Vigor-25, Actra-Rx, or 4EVERON. These products are promoted and sold on web sites as "dietary supplements" for treating erectile dysfunction (ED) and enhancing sexual performance, but they are in fact illegal drugs that contain potentially harmful undeclared ingredients. Chemical analysis by FDA revealed that Zimaxx contains sildenafil, which is the active pharmaceutical ingredient in Viagra. The other products contain chemical ingredients that are analogues of either sildenafil or a pharmaceutical ingredient called vardenafil, which is the active ingredient of Levitra.

These undeclared ingredients can interact with some prescription drugs, in particular nitrates. In combination with nitrates, they can cause a catastrophic fall in blood pressure. You may have seen Keanu Reeves warn Jack Nicholson about that in the 2003 movie Something’s Gotta Give.

We have seen so many examples of adulteration of herbal remedies and supplements, and I’ve written a previous item about this huge problem. Huge, not in terms of numbers of cases, but in terms of the potential for harm.

I always recommending reading the label whenever you buy anything. The problem with the products mentioned in this latest FDA warning, is that there was no indication that the products contained drugs. Also be careful about whose advice you trust. Several years ago, a study done in health food stores in the United Kingdom showed that most of the staff knew very little about the products that they were promoting. Things have improved in recent years: we have a couple of health food stores in Atlanta with very knowledgeable staff. But it’s always a good idea to check before accepting the advice of someone in a store. Be doubly careful if you are buying things online: it’s you body.

So Caveat Emptor!

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