What you need to know about insulin resistance
Alan B. McDaniel, MD
Why is it so hard to lose weight? Why do I gain weight when I use nothing but stevia to sweeten my food? Why is my cholesterol so high when I eat hardly any? Why does everyone in my family get high blood pressure, strokes or heart attacks? Why does my husband snore so badly when he’s not even overweight? All these questions and more are easily answered when you understand insulin resistance.
Our ancestors faced starvation. In ancient times, before we had cash to buy groceries; before we had canned or smoked or dried food; our “wealth” and indeed our insurance against famine was the nutrition we stored in our body fat. In primitive societies into the present day, body fat is desirable.
At least 100.000 years ago, one of our ancestors developed a mutation, a change in his genetic program that made him more fuel efficient. He consumed less energy and was able to store more of it, against future need. This DNA mutation was perfect for primitive peoples and greatly enhanced their survival. This same gene mutation that protected our ancestors against famine allowed them to have more children, who were larger at birth and better able to survive. These bigger babies grew up into larger, stronger adults and the tribe had a great competitive advantage.
This gene is now carried by 40% of all Americans. While it gives us many gifts during bad times, it is now causing us great suffering. Because of changes in our diet, life-style and nutrition, these “thrifty” genes are now killing us. These genes lead to obesity, sleep apnea and diabetes; high blood pressure, kidney disease, heart attacks and stroke; polycystic ovaries (PCOS), menstrual problems and infertility; low-testosterone and in general, chronic illness, reduced quality of life, increased lifetime medical expenses and shortened life-span. Fortunately, all of these problems are preventable. Of course, all of these conditions have been known for thousands of years. How they are all linked together was not known until Stanford’s Dr. Gerald Reaven spelled it out for us in 1988. However, it takes new truths about 20 years to become generally known. These lessons are old but new.
The “thrifty gene” requires the carrier to release more insulin than normal to control her blood sugar. This is called Insulin Resistance. Every year, she gets slightly more resistant and has to make ever more insulin to keep her blood sugar normal. Ultimately, she may not be able to make enough insulin to overcome her resistance and her sugar goes high. This is diabetes and it is just the tip of the iceberg.
Insulin is a hormone that is released in two phases: As soon as something sweet touches your tongue and then more when your blood sugar rises a bit later. Insulin triggers your muscle cells to soak up great amounts of blood sugar very quickly – to this effect there is resistance. Insulin also has many other effects on our body and there is no resistance to these effects. As Hamlet said, “Therein lies the rub.” Insulin is an energy-storage hormone. Excessive insulin makes us grow excessively fat and it raises our blood fats (triglycerides and cholesterol) as well. Oh, did you think that higher than normal amounts of insulin wouldn’t effect people who are insulin-resistant? Well, so did doctors for years but as it happens, insulin does many things and only its blood sugar-lowering effect is blocked in insulin resistance. There is no resistance to insulin’s effects to make us store energy as glycogen and in particular fat.
Higher-than-normal insulin levels change how our brain regulates body functions. As a result, we get high blood pressure and make more adrenal steroids than usual, which make us fatter and raise our blood sugar. Our daughters reach puberty earlier. We make more stomach acid than normal and so get reflux. Excessive insulin levels mimic other hormones. Insulin cross-reacts with Growth Hormone receptors, causing people with IR to grow larger (professional football players are nearly all IR). Unfortunately, this also makes cancers and tumors grow more quickly. Insulin also acts like the hormone Aldosterone, making the kidneys increase salt retention and worsening our high blood pressure.
High insulin levels directly stimulate the adrenal glands to make both adrenaline (worsening our high blood pressure) and even more steroid hormones – which further raise our blood sugar and make us fatter. The ovaries are hit hard, causing them to make lots of cysts (PCOS) and transforming their supporting cells to actually resemble testicles. These damaged ovaries make too much testosterone. This gender-bending doesn’t stop here. Insulin also alters the way women and men process their sex hormones. Overly-robust insulin levels cause women to make too much testosterone and estrogen, while losing progesterone. They get “estrogen-dominance,” PMS, acne, facial and body hair growth and male-pattern baldness. In contrast, insulin causes men to convert their testosterone to estrogen. They lose muscle mass and gain abdominal fat; get breast and prostate enlargement and all the symptoms we call “low-T,” including early death.
The last bad thing we’ll look at is the role of high insulin in causing heart attacks and strokes. Insulin is a pro-inflammatory hormone. Research shows it damages the lining of our blood vessels in many ways. This damage leads to narrowing and hardening of the arteries. This in turn leads to heart attacks and strokes, as well as kidney failure, amputations and retinal disease.
Metabolic Syndrome
All this information is the fruit of research conducted in the last two decades. Until 1988, doctors believed IR was no more than a risk factor for diabetes – they thought high blood sugar levels caused all the ills of the diabetic. Now we know that high insulin damages our bodies for decades before diabetes develops – and indeed, may cause premature death even when blood sugar levels have never been high.
The constellation of problems caused by high insulin is called the “Metabolic Syndrome.” Decades ago, physicians saw that people who became diabetic had a similar history. They had been overweight with high blood triglycerides and cholesterol, high blood pressure and trouble keeping their blood sugar level for many years. This Metabolic Syndrome is caused by IR and the effects of high insulin. All this is preventable.
Solutions
Understanding the cause of the Metabolic Syndrome and of the problems it creates allows us to prevent them. There are four approaches to keeping us healthy: Diet, life-style, supplements and drugs/ herbs. Our goals are to improve insulin sensitivity and reduce the need to make insulin. That’s all it takes!
Diet
Here’s where we reduce the need to make insulin. The best diet for IR can be described in three ways: Low-Glycemic Index; slowly-accessible glucose and low Insulinemic Index. Let’s examine each of these briefly.
Glycemic index (GI) measures the amount of blood sugar (as glucose) a particular food gives us. It was “invented” in 1981 as a way to help diabetics keep their blood sugar under control and reduce their insulin requirements. It has been proven to help people with insulin-resistance, too. Because IR is about insulin more than about blood sugar, though, the Glycemic index by itself is not sufficient.
The second important feature of a good diet for IR is “slowly-accessible glucose.” We must understand that a healthy diet should give 40 to 50% of its calories as “slow” carbohydrates. All carbohydrates are made of sugars, the way words on a page are made of letters. To reduce the need for insulin, we must eat “carbs” that will release these sugars slowly. When a person with IR eats rapidly-accessible glucose (“fast-carbs”), it is like putting gasoline into a kerosene lantern – it just makes a real mess! “Slow-carbs” are vegetables – green, yellow, orange, red and purple.
The third feature of a healthy diet for IR is a low Insulinemic Index. While the GI shows how much a given food raises the blood sugar, the Insulinemic Index shows how much insulin release a food will provoke. There’s a big difference between the two! Of course, if a healthy diet minimizes the amount of insulin we must make, it will be a low-Insulinemic Index diet, right?
Most diet studies have been performed before Insulin Resistance was understood. Once, doctors believed only the amount of calories we eat was important for weight control. Low-fat, calorie-restricted diets are still commonly recommended and they work for some people. Recently, researchers began to understand IR. They have compared the calorie-restricted, low fat diets against low-GI, slow-carb and low-insulinemic index diets like the Mediterranean and Atkins diets. For people with IR, Atkins and Mediterranean are significantly better. Restriction of calories is not as important as what kinds of foods you eat, and how your body responds to them.
Which brings us to sweeteners: Sugar is sweet and sweets cause our body to release insulin – which makes us fat. Our body “wants” to be fat; it is an energy savings account – so our body craves sweets and it is fun to make deposits. Sweeteners, even natural ones like stevia, have a zero glycemic index. They give us a nice, sweet taste without raising our blood sugar. However, they have a high insulinemic index, just like sugar.
Now hear this: Sweeteners including stevia make us fat. Though they give us no calories, sweeteners cause us to release insulin by a taste-reflex. Insulin causes our body to convert our blood sugar to fat for storage – and we end up with low blood sugar. Have you wondered why so many people carrying diet drinks also carry a bag of snacks? They are keeping their blood sugar from dropping!
Is this possibly right? References on file at the NIH National Library of Medicine web site “Pub Med” state that drug companies are trying to make proteins from stevia (called “steviosides”) into drugs to increase diabetics’ insulin production. Sweeteners, even “natural” ones, make us fat and people with IR should avoid them for that reason. If it tastes sweet on the tongue, it makes you release insulin.
Unless my patient is already diabetic or a “sugar-holic” who once started can’t quit eating it, I recommend following a careful diet for six days a week and then having a “Sabbath” day. Eat anything you want on that day and get it out of your system – it won’t hurt you nearly as much as a little, unsatisfying “cheat” every day. Knowing that glorious day is coming helps most people keep a good diet the rest of the week.
Lifestyle
Here, only two things are really important: Physical activity and adequate sleep. Since our muscles are the most important organ effected by insulin resistance, it makes sense that putting them in top physical condition would be essential. Indeed, just 30 minutes of some sort of physical activity daily greatly improves insulin sensitivity. This effect is many times stronger than that of our best drugs and it has been proven repeatedly in research studies.
Sleep seems a peculiar association with IR but only until we realize that the lack of sleep is very stressful. All sorts of stress worsen insulin resistance – a response our ancestors used to stay alive longer when they were sick, injured, freezing or starving. The lack of sleep very significantly worsens insulin resistance. It seems most adult humans need between 8 – 9 hours sleep every day to perform at their best.
Supplements
Many supplements are marketed to improve insulin sensitivity. Some of them act like drugs (berberine and vanadium, for instance). Chromium, however, is a nutrient that is essential to glucose uptake into our cells. Deficiency of chromium worsens insulin resistance and supplementation has repeatedly been studied and proven to increase insulin sensitivity, even to helping diabetics control their blood sugar. Although chromium picolinate is well-marketed, it is poorly-absorbed; at least 1,000 mcg must be taken daily. Chromium tri-chloride is much more easily absorbed. Biotics sells it as Aqueous Chromium; one drop (150 mcg) twice-daily is all you need – if you need it at all. About 70% of my patients say it helps and 50% report they completely lose their sugar cravings taking it!
Drugs
If all else fails, drugs help. Sometimes, a prescription is needed to get people “unstuck” out of the rut in which they’ve gotten caught. There are two classes of prescription drugs that can help. Stanford’s Dr. Reaven studied the TZD (or “glitazone”) drugs and proved them useful. The TZDs include Actos® and Avandia® and both are under withering scrutiny for causing complications. I believe this is because they don’t “fix” the problem that causes IR; they just make changes that mitigate many ill-effects of IR and increase some “good” effects of insulin. The down-side is that some of the bad effects of insulin may also be increased, like fluid retention and weight gain.
The second drug, metformin, seems to target the precise cause of IR (trafficking proteins that mobilize the GLUT-4 transporter in muscle and fat cells). However, it is not very strong. Its use has been repeatedly proven successful compared to placebo – though it may be no stronger than the herb berberine. Metformin’s greatest advantage is that taking it should not make you fatter, as the TZD drugs can. Harvard docs recommend using it to help significantly obese patients (BMI over 35) get “unstuck.” Its worst side-effect is blocking the absorption of sugar in your diet, which causes gut symptoms similar to lactose intolerance. Don’t take the metformin on your dietary-Sabbath day, OK?
Summary:
Insulin resistance is common and up to 40% of Americans carry that genetic program. It is a great advantage for surviving hard times. The combination of our modern diet and lifestyle with this gene has created our current epidemic of obesity, diabetes, chronic illness and premature death. Research has shown us the cause of IR. There are many strategies for coping with this condition. Research is beginning to show us good combinations among many that can be successful. While medical interventions are helpful, prevention is the key. Even the most insulin-resistant person can live a long and healthy life when he or she applies the principles we’ve outlined above.
Alan McDaniel, MD is a Board-certified Ear, Nose & Throat specialist with two sub-specialties. His work with dizziness and allergy in the 1980s led him to seek solutions for Chronic Fatigue Syndrome. Since 2003, Dr. McDaniel has taught physicians practicing on five continents to effectively employ nutrition and hormones for this and other issues in his two-day course titled “The New Endocrinology.” Dr. McDaniel has been working as a visiting physician at Gordon Medical throughout the past year.