Can't lose weight? It could be a problem with insulin.
Insulin resistance causes obesity, heart disease, polycystic ovarian syndrome and rapid ageing. It also increases the risk for cancer, Alzheimer's disease, menopausal symptoms and osteoporosis.
How could one little hormone do all that?
What is insulin?
Insulin is an ancient, anabolic hormone, which is found in all forms of animal life.
Insulin's main function is to stimulate the cell to store nutrients. This was important in the days when starvation was a real possibility for our ancestors. In our modern era of abundant food, "nutrient storage" is not something that we want to promote in our bodies.
Hormone of ageing
Insulin does more than store nutrition. It has been shown to limit the lifespan of cells. In other words, it is the chemical signal that determines when a cell has lived long enough and it's time to die. In this way, insulin can be thought of as the hormone that promotes ageing. Certainly, in humans, excess insulin accelerates the rate of ageing.
Insulin sounds bad, and yes, in excess it is harmful, but do not forget that it is essential for life. Without insulin, our cells cannot use food for energy. Before the invention of injectable insulin, diabetes was a life-threatening disease.
What is insulin resistance?
Under normal circumstances, insulin is tightly controlled by a natural homeostatic feedback mechanism. Every time that you eat, and every time that protein and carbohydrates enter your bloodstream, your pancreas releases insulin. Your insulin receptors, which are located in every cell, then respond to the hormone. Your cells take up the carbohydrates and other nutrients, which drops your blood glucose, which then feeds back to your brain and your pancreas to reduce the production of insulin.
The problem starts when the tissue fails to respond to insulin. When this happens, the sugar in the blood remains high despite the presence of insulin, and the body has no choice but to release more insulin. It becomes a vicious cycle because it is actually the presence of insulin that makes the tissue more and more resistant to it.
This is how insulin exposure determines the rate of ageing: with every insulin release, cell membranes become a little bit more insulin resistant. A gradual increase in insulin concentration over time is normal, but the current epidemic of severe insulin resistance is a modern phenomenon.
Insulin resistance may be the cause of many of your health problems
When your body becomes resistant to insulin, it cannot metabolise carbohydrates properly. Untreated, this leads to Type 2 diabetes, which affects 1 in 200 Australians.
Decades before it becomes diabetes, however, Insulin Resistance can cause real problems. As the master hormone, it's presence in excess can lead to many different conditions such as:
- high cholesterol
- high blood pressure
- heart disease
- Alzheimer's Disease (3)
- polycystic ovarian syndrome
- breast cancer (4)
- prostate cancer (5)
- under-active thyroid
- premature ageing
A problem with insulin worsens menopausal symptoms
- Low libido. Women with insulin resistance are more likely to experience a drop in libido with menopause. (6)
- Osteoporosis. Women who are overweight and/or diabetic are more at risk for osteoporotic fractures. This overturns the conventional belief that body weight protects against osteoporosis. Overweight women often have normal bone density scores, but they go on to suffer fractures anyway. Excess insulin causes bone remodeling cells to degrade into fat cells. In this regard, osteoporosis can be viewed as "obesity of the bone".(7,8,9)
- Hot flushes. A new study from the University of California has found that women who are overweight are more likely to suffer hot flushes. Weight loss causes a significant improvement in symptoms. (10)
Perhaps you take different medications for your cholesterol, blood pressure, and thyroid but those are only band-aids. They do not address the insulin resistance that may be the single problem that is causing the other conditions.
Do you have insulin resistance?
As many as 25% of Australians may suffer from this underlying problem of insulin resistance. Most are not aware that they have it.
Insulin Resistance is such an important health condition, and yet it may be completely off your doctor's radar. Forget your cholesterol and your female hormone readings on a blood test, and look deeper.
Ask yourself this very important question: "Are you a pre-diabetic?" Here are some warning signs:
- fasting glucose greater than 5.0 mmol/L (the official reference range is 3.5-6.0)
- elevated triglycerides and bad cholesterol (LDL)
- elevated ALT on liver function test
- waist measure greater than 80cm for women and 90cm for men
- high blood pressure
The definitive pathology test for insulin resistance is the Glucose Tolerance Test (GTT) with insulin. One hour after the glucose load, normal insulin should be less than 60mU/L. Other useful tests include fasting insulin, fasting glucose, liver function test, lipid profile, C-RP, thyroid function and serum vitamin D.
For other symptoms, see our Insulin Resistance Quiz.
Why does it happen?
- Sugar or fructose. Please read The Case Against Sugar.
- Pollution: A study published in Diabetes Care has found that people who have the highest level of stored toxins were 38 times more likely to have diabetes than people with a lower level of stored toxins. Even if they were overweight, people with low level of toxins did not develop diabetes.
- Herbicides: Rats exposed to low doses of the common herbicide Atrazine gained 10% more abdominal weight over 5 months than non-exposed animals. The cells of the exposed rats were found to contain damaged mitochondria, which prevents normal cell response to insulin. Blood tests showed significantly higher blood sugar and insulin levels. (13)
- Smoking: Toxins in cigarette smoke damage the insulin receptor, and cause distinctive weight gain around the waist. (14) No more smoking to stay thin!
- Inflammation: New research from the University of Maryland has correlated inflammatory products in the blood with insulin resistance. This means that inflammation caused by infection, stress and pollution may be a direct contributor to insulin resistance and its outcomes: obesity, diabetes and heart disease. (15)
- Trans Fat: Trans fats are damaged polyunsaturated fatty acids, found in processed vegetable oil such as margarine, deep-fried food, or commercially prepared oil. Conventionally touted as the healthy oils, these Frankenstein molecules have become a large part of the modern diet. They are damaged, distorted molecules, and when they are incorporated into the cell membrane, then interfere with the functioning of the insulin and other receptors.
- Vitamin D deficiency has been linked with Insulin Resistance.
- Birth control Pill worsens insulin resistance.
- Lack of exercise
- Problems with digestion. (unhealthy intestinal bacteria)
Natural Treatment for Insulin Resistance
The good news is that insulin resistance is reversible with diet and lifestyle.
- Detoxify. Help your body to remove stored residues of pollutants, cigarette smoke and herbicides.
- Intermittent fasting. Research from the Institute on Aging has shown that intermittent fasting improves insulin sensitivity. When participants skipped the evening meal, their fasting insulin improved, and they had fewer inflammatory markers on blood tests. (17)
- Quit sugar. Please see my quit sugar post.
- Eliminate refined sugar from your diet. Sugar is the worst kind of carbohydrate.
- Eat protein regularly. Protein curbs the release of insulin and stimulates the production of the hormone glucagon, which opposes insulin. (Do not increase protein if you have kidney problems, and do not exceed 90-100 grams of protein per day.) Good sources include 2 eggs (12 grams protein), 1 chicken breast (25 grams protein), 2 lamb chops (29 grams protein), 25 grams whey protein (23 grams protein).
- Avoid Trans fat. Eliminate soy oil, corn oil, cottonseed oil or any generic "vegetable oil". Particularly bad are margarine, vegetable oil spreads, and deep-fried food. Eat only naturally occurring fats such as butter, avocado, olive oil, coconut milk, meat, fish, and nuts and seeds. It can take up to 6 months to give your cell membranes an "oil change".
- Exercise. Strength training dramatically improves insulin sensitivity. When the muscles increase their energy expenditure, they re-learn how to use carbohydrates rather than store them. Weight loss occurs not simply because of the calories burned, but because of a shift in metabolism. Exercise is also effective to relieve stress, a common cause of inflammation and insulin resistance.
- Avoid Wheat. Gluten generates inflammation and disrupts the insulin receptor, thereby worsening insulin resistance. (18) Avoid flour-containing bread, pasta, cereal, and biscuits. If you do have flour, choose flour made from rice, oats, barley, spelt, and rye. Ordinary "flour" is wheat.
- Mediterranean diet. Newly diagnosed diabetics can reduce their need for medication by following the Mediterranean diet. Only 44% of patients on a Mediterranean diet required sugar lowering medication compared to 70% of patients who followed a standard low-fat diet.(19)
- Nutritional supplements and herbs. Chromium, magnesium, selenium and omega 3 fatty acids will improve insulin's effectiveness at the cell membrane. B-vitamins and amino acids assist the liver to remove pollutants. Antioxidants such as vitamin C and vitamin E will act as natural anti-inflammatories. Gymnema and Bitter Melon have been documented to improve insulin sensitivity. Vitamin D should be supplemented once a deficiency has been determined on blood test.
- Correct Gut flora. Friendly bacteria in the intestine assist with weight loss. Changing the gut flora may improve insulin sensitivity and promote weight loss. (20) Intestinal flora is negatively affected by junk-food diet, antibiotics, and Pill use. Lactobacillus supplements may be of benefit.
For more information on weight loss, click here.
- Eaton SB, et al. An evolutionary perspective enhances understanding of human nutritional requirements. Journal of Nutrition 1996:126:1732-1740.
- Ron Rosedale. Insulin and its Metabolic Effects. 1999. Designs for Health Institute.
- De Felice et al. Protection of synapses against Alzheimer's-linked toxins: Insulin signaling prevents the pathogenic binding of A%u03B2 oligomers. PNAS, 2009; DOI: 10.1073/pnas.0809158106
- DelGiudice, ME et al. Insulin and Related Factors in Premenopausal Breast Cancer Risk. Breast Cancer Res Treat 47
- Wolk A. et al. Insulin-like growth factor 1 and prostate cancer risk: a population-based, case-control study. J Natl Cancer Inst. 1998 Jun 17;90(12):911-5
- Chedraui, P et al. Hyperglycemia in postmenopausal women screened for the metabolic syndrome is associated to increased sexual complaint. Gyn Endocrin 2010; 26(2): 86-92
- Zhao,Lan-Juan. Relationship of obesity with osteoporosis. J Clin Endocrinol Metab. 200. 92(5): 1640-1646.
- Khalil, N et al. Menopausal bone changes and incident fractures in diabetic women: a cohort study. Osteoporosis International 2010; aop:10.1007/s00198-010-1357-4
- Rosen CJ et al. Mechanisms of decrease: is osteoporosis the obesity of bone? Nat Clin Pract Rheumatol 2006; 2(1): 35-43.
- Huang, Alison J et al. An Intensive Behavioral Weight Loss Intervention and Hot Flushes in Women. Arch Intern Med. 2010;170(13):1161-1167
- Lee, DH et al. A strong dose-response relation between serum concentration of persistent organic pollutants and diabetes: Results from the National Health and Examination Survey 1999-2002. Diabetes Care. 2006: 29: 1638-1644.
- Porta, M. Persistent organics pollutants and the burden of diabetes. Lancet. 2006: 368: 558-559.
- Lim S et al. Chronic Exposure to the Herbicide, Atrazine, Causes Mitochondrial Dysfunction and Insulin Resistance. PloS One. 2009; 4(4): e5186
- Weitzman M et al. Tobacco Smoke Exposure Is Associated With the Metabolic Syndrome in Adolescents Circulation 2005 :S1524-4539
- Ryan, A. Inflammation linked to postmenopausal glucose metabolism. Diabetes Care 2004; 27: 1699-705
- Elliot, SS et al. Fructose, weight gain, and the insulin resistance syndrome1,2,3. American Journal of Clinical Nutrition 2002 76(5): 911-922
- Mattson, MP et al. Beneficial effects of intermittent fasting and caloric restriction on the cardiovascular and cerebrovascular systems. The Journal of Nutritional Biochemistry 2005. 16(3): 129-137
- Yevdokimova, N. and Andrej Yefimov. Effects of wheat germ agglutin and concanavalin A on the accumulation of glycosaminoglycans in pericelluar matrix of human dermal fibroblasts. A comparison with insulin. Acta Biochemica Polonica 2001, 48(2):563-572
- Esposito, K et al. Effects of a Mediterranean-style diet on the need for antihyperglycemic drug therapy in patients with newly diagnosed tyep 2 diabetes: a randomized trial. Ann Intern Med. 2009; 151(5): 306-314.
- Vrieze A et al. Metabolic effects of transplanting gut microbiota from lean donors to subjects with metabolic syndrome. EASD 2010; Abstract 90.