Richard G. Petty, MD

Pesticides, Weight Gain and Insulin Resistance

On this blog and in Healing, Meaning and Purpose, I have talked about some of the less well recognized contributors to obesity, including:

1. Stress
2. Salt
3. Viruses
4. Pesticides
5. Intestinal bacteria

There is some new evidence from Korea published in the journal Diabetes Care, supporting the possible contribution of pesticides to insulin resistance.

People with high levels of persistent organic pollutants (POPs) in their blood were more likely to develop insulin resistance, which may lead to type 2 diabetes. Insulin resistance may also lead to obesity, hypertension and an array of other diseases. It is well recognized that increasing amounts of intra-abdominal fat may increase insulin resistance. It is less well known that this obesity is part of a viscous circle, with insulin resistance being associated with elevated insulin levels that may cause fat to be laid down throughout the body. Once the fat is laid down in the abdomen, it can break down, releasing fatty acids and triglycerides that in turn affect the breakdown of insulin by the liver and the release of insulin by the pancreas.

Previous research by the same group found a link between POPs and type 2 diabetes. This study confirms that background exposure to some POPs, chemicals such as organochlorine pesticides and polychlorinated biphenyls (PCBs), is also associated with insulin resistance among people who do not yet have diabetes.

The researchers also found that the association between organochlorine pesticides and insulin resistance became stronger as people got fatter. However, among people who had very low concentrations of pesticides in their blood, the researchers found little association between waist size and insulin resistance.

Some studies have suggested an association between background exposure to POPs and a variety of adverse health effects in humans and wildlife. POPs can be particularly problematic because they persist for long periods of time in the environment, accumulate up the food chain, and can travel great distances through the air and water. Therefore, even people and animals that live nowhere near a place where POPs are being applied often show high levels of these chemicals in their bloodstream.

An international treaty banning a dozen of the world's most dangerous POPs has helped reduce exposures, but many harmful chemicals remain in use and even those that have been banned may linger in our environment for years to come. For example, chlordane was banned two decades ago in the United States but continues to be present at high levels in our food supply.

The researchers concluded that some POPs "may be involved in the pathogenesis of insulin resistance." They advise urgent prospective studies among those who have background exposure to POPs, which mostly comes from eating fatty animal foods. Since obesity may increase the toxicity of POPs, controlling weight could also help to reduce the impacts of these molecules.

In separate research involving mice, Frederick vom Saal from the University of Missouri in Columbia, Missouri has studied the effects of a different class of endocrine-disrupting chemicals, including bisphenol-A (BPA). Not long ago, BPA made news in San Francisco, where there was a lot of controversy over an ordinance that seeks to ban its use in children's products. vom Saal's most recent work was presented at the 2007 Annual Meeting of the American Association for the Advancement of Science (AAAS). He found that endocrine-disrupting chemicals cause mice to be born at very low birth weights and then very rapidly gain abnormally large amounts of weight: they could more than double their body weight in just seven days. Vom Saal followed the mice as they got older and found that these mice were obese throughout their lives. He said studies of low-birth-weight children have shown a similar overcompensation after birth resulting in lifelong obesity.

(Regular readers might remember the concept of the thrifty phenotype, and see how this research ties in with that concept). More research must be done to determine which chemicals cause this metabolic effect. According to vom Saal, there are approximately 55,000 manmade chemicals in the world, and 1,000 of those might fall into the category of endocrine disrupting. These chemicals are found in common products, from plastic bottles and containers to pesticides and electronics.

These chemicals are so pervasive that it is difficult to avoid them, and there is scant evidence that "detoxification" helps clear them. That being said, and depsite the lack of evidence, we recommend certified organic produce and regular mild detoxification programs, together with nutritional support and  tapping therapies.

Acids and Alkalis

Have you seen those books and advertisements about supplements that are supposed to “alkalinize” your body and therefore avoid the effects of nasty acids? Many have frightening titles, like “Alkalinize or Die.” Some time ago I read a whole bunch of these books while I was trying to help two people with interstitial cystitis. This is a nasty problem, and I had failed to help with conventional medicine, naturopathy, acupuncture or homeopathy. One of the many books that I read claimed that altering the acidity of the urine would cure the problem. It did not.

The basis for these claims that we need to alkalinize our bodies comes primarily from three sets of observations:

1. That manipulating the external environment of cells in culture and isolated organs can have dramatic effects on the activity and life expectancy of these cells and organs
2. That some of the products of exercise or metabolism are acidic, and so need to be buffered or expelled from the body
3. A great many anecdotes about people benefiting from following an “alkalinization” protocol of some sort.

That all sounds good, but it is a big jump to go from cells in culture and perfused organs to whole human beings. Or to base medical advice on anecdotes ALONE.

There is also another origin for some of these ideas, and they derive from the work of Edgar Cayce and some oriental healing traditions: I have enormous respect for both.

I'm a card-carrying biochemist and metabolic physician, so some things about acid/base balance I know well.

Our blood is maintained at a pH of 7.42, and even the tiniest shift can cause major health and psychological problems. So there are sophisticated systems for keeping things in balance. Most of the popular books fail to mention much about the easiest way to change pH, and that is by changing your rate of breathing!

We show people how to do that every day in clinical practice. And when doing electrical recordings of the brain – electroencephalograms - hyperventilation is a good way of inducing some types of abnormal electrical activity.

We know a great deal about how changes in the pH of the blood can impact behavior and many physiological approaches. I’ve worked with hundreds if not thousands of people with disturbances in the acid/base balance of their bodies. Usually as a result of diabetes that was out control, but also scores of other illnesses. Many of them rare but educational.

The populist writers then often talk about excess acid being a stressor. So we don’t want to have acid in our systems because it depletes the alkaline buffers that are supposed to keep things in balance. An interesting idea, but one that can quickly be shown to be deeply flawed. It’s easy for a biochemist to calculate the amounts of acid in single cells, organs and the whole body. We’ve done it thousands of times when treating people with medical conditions like diabetic ketoacidosis and lactic acidosis.

Sadly some of the writers of popular books and articles on acids and alkalis have clearly not studied the literature in any detail.

There have also been some examples of what we call the “Trudeau effect:” vague comments about studies that are supposed to have been completed, but which, if they have been read at all, have never been analyzed by the writer. And often odd statements from books and from research are taken out of context and cited as the Gospel truth. There’s a legal loophole that Trudeau and some others get away with saying things about health that are not supported by any data.

Levels of Evidence
An important concept is what we refer to as levels of evidence. In the past it was often thought that the only kind of evidence to be of any value in clinical decision making had to have been obtained by randomized controlled trials. Yet we all know from experience that there are other types of evidence. A teacher or a colleague may have recommended a course of action based on experience or observation, and this can provide valuable guidance. We now recognize four types of clinical evidence:

1. Case reports
2. Case series and uncontrolled observational studies
3. Retrospective database analyses
4. Controlled analytic studies, including randomized clinical trials

You will see from this is that even single case reports go into the mix. Numbers one and two and used not as proof, but as ways to generate testable hypotheses.

If you tell me that you have slept better since you started an alkalinization regimen, I’ll see if what you are doing can be applied to others (that’s a pragmatic study), and also whether there could be an explanation for your report (that will need an analytic or mechanistic study).

When we review evidence or perform meta-analyses we give each type of evidence a rating. Controlled studies are given a higher rating than case reports, because the evidence can be generalized to many individual patients. A further refinement is to factor in the source of the study. So research by a pharmaceutical company or a manufacturer of an herbal supplement tends to get a lower rating than an independent study.

Recently someone did indeed tell me that she had slept better since following a special diet. When we looked carefully at the protocol that she was following, it was probably not the alkalinization, but the hops in the diet.

There are many, many claims of health benefits from various diets. The benefits may be genuine, but we need to be very cautious about attributing the success of a diet or any other form of treatment to just one factor.

There is no question that some illnesses, for instance peptic ulcers or gastro-esophageal reflux disease can be made worse by eating an acid diet, and having acid urine can sometimes be very irritating to the bladder.

But the evidence for the benefits of alkalinizing of the whole body – even if it were possible to do it - just does not exist.

You also need to be aware of a potential consequence of "alkalinizing diets:" they can dramatically alter the absorption of some herbs, medicines and supplements.

So what should you do?

1. The key to any diet is balance: it would be a mistake to be on a diet consisting of just one thing. Experts are always very wary of health claims based on one juice, herb or supplement. Your body is not designed that way: you need a mixture of different fruits and vegetables. When someone tells us that the key to healing is a berry that can only be found in a hidden valley in the Himalayas, we have to ask, “How could that have happened?” How could it be that we evolved or were created with a key ingredient missing?
2. Avoid drinking carbonated drinks. The old story about a can of Pepsi Cola being a good way to remove oil from your driveway is true. In high school we did the experiment of taking a small nail and leaving it in a sealed container with some carbonated soda. The nail had largely dissolved inside a week.
3. Keep up your intake of pure water. The current recommendations vary depending upon the time of year and where you live. In the Southern United States, during the summer time, it is currently recommended that you should drink 120 fluid ounces of pure water each day. I personally prefer pure spring water or distilled water. But also bear in mind that if you choose not to drink fluoridated water, that your chance of dental cavities increases. You can get around that problem by applying fluoride directly to your teeth and then rinsing it out. Ask you health care provider about that.
4. Listen to you body: you should avoid anything that feels irritant, causes indigestion, diarrhea or urinary symptoms
5. Use you intuition: the answers are within you. One of the most valuable uses of your intuition is not to help you pick lottery numbers, but to help you make wise decisions about your body, your relationships and your subtle systems. I have already written a little about some techniques for listening to and amplifying your intuition, and I shall soon be writing and recording a lot more about those essential topics.

Using Yoga: Some Measurable Effects in People with Alcohol Dependence

I was very interested to see a quite well designed pilot study which seems to show some clear antidepressant and hormonal effects (reduction in cortisol and increase in prolactin levels) in alcohol dependent individuals who could be persuaded to practice something called Sudarshana Kriya Yoga (SKY). This technique involves rhythmic hyperventilation at different rates.

Studies like this are difficult to perform, and this one was not perfect. It only involved males, and the study will inevitably be skewed by the kinds of people participating. The study involved quite a bit of time, and so the subjects had to be motivated. Some people still dropped out of the study, and their data should have been included in the analysis. They also had more than just the breathing exercises: they got a whole treatment package. It will be interesting to see how long the effects last. We're always interested to see how many people remain abstinent at one year.

One of the odd things was that the investigators measured the hormone prolactin. It is so named because its primary role is to promote lactation. It has at least 300 hundred other functions in the human body, and has at least ten major control systems. It is a little surprising that it should rise, since it normally goes up when people are stressed. However, I might have an explanation. As far as I can see, the techniques used in the study are pretty straightforward yogic pranayama. Hyperventilation slightly alkalinizes the blood. That would change the rate of firing in the reticular activating system of the brain stem, and could of itself be responsible for the elevated prolactin levels. Had I been designing the study, I would have measured arterial pH: it would have helped answer several questions.

Though not perfect, this study is a good piece of pilot data, and should stimulate further research into the use of these techniques for helping a very difficult problem.

I was interested to find out more about the technique. SKY was devised by a spiritual guru - Sri Sri Ravi Shankar - of the Art of Living Foundation in Bangalore, India. He has established a Foundation that seems to be engaged in a number of charitable activities. I have known a great many spiritual teachers; each has been criticized and controversial, and Shankar is no exception. I’m not in a position to judge whether or not it is justified.

All that I can say for now is that he has devised a technique rooted in the Indian classics, that seems to help some selected patients with an otherwise tough problem. And that is a good start.