Insulin Resistance and Diet Myths and half Truths

As I read others blogs and published articles about Insulin resistance a small semantic matter keeps cropping up.  Lets be clear Insulin resistance is the same thing as "carbohydrate tolerance".
  Early warning signs of possible insulin resistance may include:  These are not necessarily specific ie there are other explanations:

• increased  thirst
• more frequent urination
• excessive hunger
• gaining a weight a few pounds here and there and having difficulty losing them
• unexplained drowsiness or feeling tired most of the time, especially after eating
• inability to concentrate
• decreased endurance during physical exertion and exercise
• inflammation with elevated CRP levels and or Sed Rate
• chronic high blood pressure
• low levels of  high-density lipoprotein (HDL, the “good” cholesterol)
• high triglyceride levels
• high fasting glucose levels 
• rising hemaglobin A1c levels

  It is true that any carbohydrate gets turned into glucose in the digestive tract but when high levels of insulin are present in the blood stream (the insulin resistance syndrome) glucose is not absorbed or used by muscle cells.  It goes instead into fat storage.  Thus the saying "it is not just the fat you eat that makes you fat, it is the sugar you eat that makes you fat".  The reasons for why we become Insulin resistant are complex and involve several mechanisms. One is diet as discussed earlier but it is only one of several important factors. A diet that includes high fat intake AND high sugar intake will reliably induce insulin resistance.  ( https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4129661/) Eating a lot of refined or at least high glycemic index carbs will stimulate insulin production and a lifetime of bad eating habits will have consequences including insulin resistance, but that is not the only reason.   Another is genetics.  Since we can't change our parents or our DNA we are stuck with that one.
Another reason that is becoming clearer is stress.  That mechanism is  potentially something we can do something about.  The stress filled life keeps high levels of cortisol, a glucocorticoid, in the blood stream. Interestingly the pathway for making cortisol in the adrenal glands starts with cholesterol.  Cortisol is a control hormone that is responsible for selecting which type of nutrient is used for energy demands of the body. We all learned somewhere that cortisol and epinephrine together are part of the "fight or flight" mechanism.  Thus its production and use has survival value and is responsible for the heroic feats accomplished by people in desperate situations. The details are important.  When confronted with a threat to existence the hormonal cascade begins.  The adrenal glands secrete cortisol and epinephrine(adrenalin) .  Cortisol floods the blood stream with glucose to give muscles the energy for combat or running.  It also inhibits insulin production briefly to prevent glucose from going into fat storage, thus favoring its immediate use for energy.  Cortisol narrows arteries and epinephrine increases heart rate. IF the stress is resolved the hormonal cascade ends and the levels of cortisol and epinephrine return to normal. Cortisol is thus anti insulin in its hormonal effects. http://press.endocrine.org/doi/abs/10.1210/jcem-54-1-131   If stress is not relieved and cortisol levels remain high the adaptive mechanism is for more insulin to be produced to counter the anti-insulin effect. Thus the connection between chronic stress and chronically high insulin levels i.e.  insulin resistance.  That is simplified but generally true. So it seems one important factor in treating insulin resistance is to deal with stress.  Whither it is mental , physical or spiritual, stress reduction by meditation, yoga, exercise, music, hobbies, vacations, or whatever works for you can help to lower cortisol production and thus be helpful in treating insulin resistance.
Sleep deprivation may be another independent ? factor in developing insulin resistance. https://www.ncbi.nlm.nih.gov/pubmed/25248582
The other effects of cortisol on the immune system, the cardiovascular system, even on fertility and ED are discussed at length in the medical literature. The association with the immune system and the role chronic inflammation plays on cardiovascular risk is becoming clearer over time.  The beneficial effect of low dose aspirin on risk of heart attack probably is tied into its well know anti inflammatory properties and its ability to inhibit platelet aggregation around arterial plaques. Recently quantitative measures of C reactive protein (CRP) have been shown to be a fair measure of cardiac risk for MI.   
 One way to learn about your cortisol status is with the Adrenal Stress Index (ASI). The index test has been available since about 1989.   Results can be hard to interpret  but it is available as a home kit. (Available from Amazon for about $175.00)  It is based on saliva so no needles involved.  Usually several samples of saliva are collected at specific times and sent to a lab for analysis. If the test shows higher than generally accepted norms and if repeated studies confirm a concerted program at stress relief would seem to be in order.
Any discussion of the hormonal aspects of obesity, insulin resistance, metabolic syndrome, etc is incomplete with out discussing the effect of thyroid hormones and sex hormones.  but that is a topic for another time     

The Musculoskeletal Time Bomb

For the past few decades Orthopedic Surgery has been the "jewel" of medicine.  The technological advances in Sports Med,  Microsurgery, Spine surgery, Joint Replacement, and  Trauma Care have been astonishing and well documented.  All of that being said, the looming problem in the US and around the world is  higher and growing demand and not enough providers to keep up.  That is the Musculoskeletal Time Bomb.  According to Steven M. Kurtz, PhD, and Kevin L. Ong, PhD by 2030, the demand for primary total hip arthroplasty (THA) is estimated to grow annually from 209,000 to 572,000 and the demand for primary total knee arthroplasty (TKA) is projected to grow from 450,000 to 3.48 million procedures.  The American Academy of Orthopedic Surgery estimates that the demand for joint replacement will double in ten years and that Total Knee replacement demand will grow by 674% and Total Hip replacement demand will go up by 174% by 2030. 
 Two often overlooked factoids are that new surgeons have different lifestyle expectations i.e. they want to work less and spend more time doing other things, in practical terms they want to do fewer cases.  The second factoid is the trend for older surgeons to retire early.  These two trends come at an inopportune time.
How to increase the supply of qualified Orthopedic surgeons to meet the increased demand is going to demand we, as a society, look at new models for educating surgeons.  It will not be easy.  I anticipate one approach will be to further expand the role of mid-level providers to do more of the office work which will allow the surgeon to spend more time in the OR, but that creates its own problems.  Most patients want to meet their surgeon before they go to the operating room, and who can blame them?  
 As our population ages it is expected to drive the demand for Orthopedics up by at least 50% over the next twenty years or so.  The combination of longer expected life spans, the obesity epidemic, and the progress of the population bubble representing the baby boomers combine into what has been called the perfect storm of unmet expectations for MS care.  Demand for specific procedures like total joints will be even higher if Kurtz and Ong are to be believed.
There are a lot of places to look for numbers on population growth but in very rough terms the Medicare population in the US is projected to increase from around 47 million in 2010 to 80 million in 2030.  Social security numbers indicate that the worker/beneficiary ratio will shrink from 3.4 to 2.3.  The potential instability is hard to overlook.
 

Insulin and Obesity

When speaking about  obesity and type 2 Diabetes insulin resistance is the problem.  Elevated blood sugar is the symptom not the cause.  Much of focus in recent years has been on treating the symptom and not the cause.  The world literature on obesity and diabetes is voluminous and often contradictory. But what is known for sure is that calorie restriction i.e. most diets have a failure rate of around 98%. Any one who has tried any of the fad diets of the last 40 years knows this to be true. Giving drugs to increase insulin production when the real  problem is to much insulin is irrational, sort of liking giving alcohol to an alcoholic to treat their addiction.  Two thousand years of medical progress indicates that the best results are obtained when the cause of a disease is elucidated and treated.  Treating symptoms is sometimes the best that we can do, but to only treat symptoms when the cause of disease is known is poor practice.  High insulin levels that result from insulin resistance are usually associated with metabolic syndrome.  The metabolic syndrome is a group of conditions involving excess weight and girth, high blood pressure, and elevated cholesterol and triglycerides. But insulin resistance is also associated with other problems like Type 2 Diabetes, fatty liver and cirrhosis.  
A few biochemical facts are in order.  Glucose and fat are the main sources of energy for the body.   Insulin is a hormone produced by the beta cells in the pancreas. Insulin circulates in the blood and controls many cellular functions foremost of which is the regulation of glucose as energy.  All carbohydrates that we eat are turned into glucose.  The rate this happens is fairly important and is measured by the glycemic index.  Foods with a high glycemic index get turned into glucose quickly and visa versa.  The Zone diet is one which aims to avoid foods with a high glycemic index.  Trying to smooth out insulin release and avoid spikes in insulin  (which is the response to sudden spikes in glucose levels) is also rational. However it may not be the best way to treat insulin resistance. A lot has been written about the paleo diet.  This is also a low carbohydrate higher protein and fat diet.  What is not mentioned often is that the paleo diet was also characterized by frequent periods of low food availability, i.e. fasting.  There is much to be said about fasting.  Dr Jason Fung has been touting the real and measurable benefits of fasting for some time. 
Fasting is an effective way to decrease insulin levels.  It seems clear that food raises insulin and no food should lower it.  The body turns to fat for energy in as little as 24- 36 hours.  Alternate daily fasting has been proposed as a way to increase insulin sensitivity i.e. lower insulin resistance.  Another benefit of fasting is increased growth hormone production.  GH helps preserve muscle mass and increases the bodies use of fat as fuel. Fasting is an overlooked tool for weight loss and the most effective treatment for insulin resistance I am aware of.  It is of historical interest that most of the worlds religions have included fasting as a tool for enlightenment and practiced by the founders.  

Zero Bound: A limit on limts?

The idea of money, the kind you can carry around in your wallet, has served civilization well.  It makes exchange a lot easier than barter for most transactions and seems to be coupled with the idea of "stored value".  After all if you can by frugality save money you are retaining something of value since you can use the unspent money to buy things you want or need at a later time.  Thus the idea of "money" as stored value seems to be intrinsic to its existence.   In the current economic universe, what many have called a "race to the bottom" interest rates have gotten so low that they bump up against the so called zero bound problem.  What is the zero bound?  On line resources like Investopedia suggests the following definition.  The zero bound problem is a limit on monetary policy that occurs when a central bank lowers interest rates to zero and effectively goes to negative rates when the set rate is less than the rate of inflation.  A simple thought experiment demonstrates the problem.  If inflation is 2% and interest rates are say 1% then the effective interest rate is -1%. That is you invest say a thousand dollars at 1% for a year and get $1,010 back But with 2% inflation your purchasing power is only $989.80   You have just hit the zero bound limit.  It is clear that this will limit the actions of a central bank in terms of its choices in stimulating a moribund economy. This has been called a liquidity trap.  The lack of liquidity is caused by hoarding cash which is rational if putting it to work gives you back less purchasing power than if you just held onto the cash.  Japan discovered this in the 90's and more recently the US Fed has been drifting toward it too.  Paul Krugman has argued that the United States is in a liquidity trap now since the monetary base has tripled between 2008 and 2011 and this failed to produce any real effect on US domestic prices or on dollar denominated commodities.  More recently Mario Draghi president of the European Central Bank pushed interests rates below zero to a minus 0.2% in Sept of 2014. Countries like Denmark that peg their currency to the Euro were forced deeper in negative interest rates.  Negative interest rates are punitive to savers since you get less back than you put in.  By the end of the first quarter 2015 about a quarter of all debt issued by Eurozone governments had negative yields. The spiral of competitive devaluations and ever lower rates seems to spread like the flu virus and most of the worlds economies are acting as if a currency war is in progress.  Even China has been lowering interest rates recently. It is unclear that lowering interest rates below zero for a significant period of time will actually stimulate a credit based economy since the incentive is to hold onto cash rather than pay someone to hold it for you.  It could bring about a monetary and fiscal destruction of the banking system and return us all to a barter economy.  Facing retirement in a sub zero interest world is challenging to say the least.  I think I need to get to work on my sandwich board,  Will Operate for Food.