Insulin Resistance and a Plant-Based Diet: What You Need to KnowOne Green Planet
In the book How Fat Works, author Philip A. Wood defines insulin resistance .. Veganism and its relationship with insulin resistance and intramyocellular lipid. The pooled odds ratio (OR) for diabetes in vegetarians vs. .. Dornhorst, A.; Frost , G.S. Veganism and its relationship with insulin resistance. This is particularly prevalent when it comes to terms such as “insulin sensitivity” and “insulin resistance”. While one of these is a precursor to the.
In fact, genetic scientists have come to believe that many, if not all, diseases have a genetic component. While some diseases develop directly from a single, inherited genetic mutation, others develop as a genetic response to environmental stressors such as poor diet, viruses, or toxins.
Elder and colleagues connected every component of the metabolic syndrome, including insulin resistance, with a genetic link and determined that genetics had more of an influence on the development of the metabolic syndrome than did environmental influences.
The Effect of Diet Some research suggests that a diet high in total, trans, and saturated fat may promote insulin resistance. Kuopio, Finland; Aarhus, Denmark; Naples, Italy; Wollongong, Australia; and Uppsala, Sweden, subjects from these countries received isocaloric diets that differed only in fat quality, not quantity. The authors concluded that the type of fat in the diet impacted insulin resistance, but quantity of fat also was important.
In the SLIM study Lifestyle Intervention on Postprandial Glucose Metabolismresearchers also demonstrated improved glucose tolerance and insulin sensitivity among participants who reduced their intake of both saturated fat and total fat.
All these studies suggest that a diet low in saturated fat but also moderate in total fat content improves insulin sensitivity.
Role in CVD Insulin resistance is a central part of a cluster of metabolic abnormalities called the metabolic syndrome. Originally discovered and labeled by Reaven as syndrome X,28 metabolic syndrome is described as the concurrence of conditions, including elevated triglycerides, central obesity, low levels of HDL cholesterol, hypertension, and impaired fasting glucose. Some long-term studies have demonstrated that insulin resistance increases the risk of CVD.
In the San Antonio Heart Study, individuals with insulin resistance had a twofold to 2. In vivo and in vitro animal and human studies have demonstrated that insulin, especially at high doses, promotes LDL cholesterol transport into cultured arterial smooth muscle cells, augments collagen synthesis and arterial smooth muscle cell proliferation thus increasing carotid intimal media thickness and reducing vascular elasticityand may turn on genes that promote inflammation, which is known to accelerate atherogenesis.
In this study, researchers measured insulin sensitivity and first-phase insulin response in participants with normal glucose tolerance and individuals with impaired glucose tolerance. At five years, both insulin sensitivity and first-phase insulin response predicted conversion to diabetes, regardless of ethnic group. While individuals with a family history of diabetes and those with a higher BMI and larger waist circumference also were more likely to develop diabetes, insulin sensitivity, and first-phase insulin response still were more significantly correlated.
The researchers drew no conclusions regarding the exact physiologic mechanisms involved. Unger and Grundy were the first to postulate that continuous overstimulation of pancreatic beta cells resulting from insulin resistance and hyperglycemia eventually could lead to beta-cell failure.
Researchers have continued to implicate the direct toxic effects of hyperglycemia and hyperlipidemia on beta-cell function as well as the effects of whole-body oxidative stress resulting from hyperglycemia in the conversion of insulin resistance to overt diabetes. Weight Loss and Improved Insulin Sensitivity Several studies have demonstrated the importance of weight loss, especially when resulting from a reduction in visceral fat mass, on the reversal of insulin resistance.
A four-year intervention involving participants in the Finnish Diabetes Prevention Study demonstrated a strong correlation between changes in insulin resistance and weight. Although this study was small researchers could follow only 52 people for the entire length of the studythe results were remarkable. Both groups experienced comparable improvements in insulin sensitivity, and researchers attributed this improvement to weight loss alone, not to the specific macronutrient makeup of the diets.
Level of fitness, as measured by aerobic capacity, was strongly correlated with insulin sensitivity in this study group. While dieting can reduce visceral fat mass and improve insulin sensitivity, caloric restriction also results in the loss of some lean body mass.
One study by Barnard and colleagues demonstrated the effects of a week, low-fat vegan diet on weight loss and insulin sensitivity.
In this study, 64 overweight, postmenopausal women were randomly assigned to a low-fat vegan diet group or a control diet group following National Cholesterol Education Program guidelines.
All About Insulin and its Relationship to a Plant-Based Diet - One Green PlanetOne Green Planet
Neither group had calorie restrictions. Participants who ate the vegan diet lost 5. Insulin sensitivity improved in both groups, with no significant difference between the two. However, the vegan group demonstrated significantly improved pancreatic beta-cell function and a reduction in intramuscular fat deposits, both indirect indicators of improved glycemic control and insulin sensitivity. Choosing carbohydrate-dense foods that are low on the glycemic index also may have beneficial effects, especially when combined with a reduction in calories and regular exercise.
A study by Kirwan and colleagues demonstrated that combining a low-glycemic diet with exercise resulted in a greater decrease in insulin resistance in older obese adults than did exercise and calorie reduction without regard to glycemic index. They cited evidence from clinical trials supporting the beneficial effects of fruit and vegetable pigments, bitter melon, green tea, cinnamon, and hops on maintaining normal cellular insulin signaling function, the key to preventing insulin resistance.
Moderate caloric restriction that facilitates the loss of abdominal fat seems to be important to improving insulin sensitivity, as does regular aerobic exercise. Some evidence suggests that replacing saturated fat with polyunsaturated fat also may contribute to reduced visceral fat mass.
Helping patients devise a diet and exercise program that facilitates the loss of 1 to 2 lbs of body weight per week eventually may help improve their insulin sensitivity. Saturated and trans fat seem to reduce insulin sensitivity more than poly- and monounsaturated fats, but total fat intake still needs to be controlled.
Encouraging patients to follow a plant-based diet featuring vegetables, fruits, beans, whole grains, nuts, and seeds also is a sensible approach. The USDA MyPlate guidelines can be an easy first step many patients can take toward including more phytochemical-packed plants and fewer foods containing saturated fats in their meals. In general, foods that are less processed tend to rate lower on the glycemic index scale.
For example, rolled oats have a lower glycemic index than instant oats. Overall, however, current research seems to indicate that the exact macronutrient balance of the diet may be less important than sustained activity, maintaining a healthy body weight and, perhaps, the micronutrient content of the foods patients consume in preventing and treating insulin resistance.
After completing this continuing education course, nutrition professionals should be better able to: Evaluate the major risk factors for developing insulin resistance. Explain how central obesity and a high-fat diet may influence the development of insulin resistance. Analyze the role insulin resistance may play in the development of type 2 diabetes and cardiovascular disease. Assess the lifestyle modifications that may improve insulin sensitivity and reduce insulin resistance.
Which of the following may trigger insulin resistance at the cellular level? Insufficient mitochondrial fatty acid oxidation b. Excessive pancreatic beta-cell insulin production d.
Decreased levels of fatty acid and glucose oxidation 2. Which of the following is a risk factor for insulin resistance? Excess fat in the hips, buttock, and thighs c. Excess visceral fat d. Exercise appears to improve insulin sensitivity and reduce insulin resistance only when individuals lose weight. In which of the following ways may central obesity contribute to the development of insulin resistance? Reducing pancreatic beta-cell activity b.
Increasing the amount of glucose circulating in the blood c. Raising blood pressure d. Releasing excess fatty acids into the blood 6. Exercise may reduce insulin resistance by influencing how well cells use which of the following for energy?
Both glucose and fat d. Insulin resistance is a major component of the metabolic syndrome. Another component of this syndrome includes which of the following? Facial hair growth in women b. Elevated levels of HDL cholesterol d.
Elevated levels of small, dense lipoproteins 8.
Veganism and its relationship with insulin resistance and intramyocellular lipid.
Which of the following diet modifications does research suggest can reduce insulin resistance? Reduced total caloric intake b. Increased intake of protein c. Reduced intake of polyunsaturated fat d. Increased intake of fiber 9. Insulin resistance can trigger the liver to produce and release glucose into the bloodstream in the fed state.
Veganism and its relationship with insulin resistance and intramyocellular lipid.
Insulin resistance ultimately can lead to the development of type 2 diabetes because the body eventually does which of the following? Undergoes complete beta-cell failure and absolute insulin deficiency b. Creates antibodies against insulin c.
Develops some beta cell failure and relative insulin deficiency d. Loses all of its cellular insulin receptors References 1. Plasma insulin concentrations in nondiabetic and early diabetic subjects.
Determinations by a new sensitive immune-assay technique. The syndromes of insulin resistance and acanthosis nigricans. Insulin-receptor disorders in man. N Engl J Med. Relationship between fasting plasma insulin level and resistance to insulin-mediated glucose uptake in normal and diabetic subjects.
Over the course of 11 years her weight fluctuated significantly, peaking at pounds in the middle of In the early part of just before starting the Mangoman Nutrition and Fitness Program, she weighed pounds and was still considered more than 50 pounds overweight.
For many years she had attempted to lose weight unsuccessfully, and at pounds she could feel the strain that extra weight was placing on her bones, joints, skin, digestive system and brain. Low Energy One of the most classic symptoms of living with diabetes is a near complete loss of energy. Many people feel that living with diabetes is a constant battle for increased vitality and energy, and no matter what food they eat, the energy never seems to come. Cynthia recalls feeling very lethargic in the morning, having to sleep until at least 8AM or 9AM just to get out of bed.
In the same way that thyroid hormone deficiency can cause a strong feeling of lethargy, living with type 2 diabetes drained Cynthia of energy, irrespective of the amount of sleep she got.
Life-Threatening Hypoglycemia Cynthia was no stranger to hypoglycemia. She had experienced 5 life-threatening episodes, and recalls her experiences here: At first, I felt weak and nauseous, and my legs felt very heavy.
I could hear things, but everything was black. These episodes were scary. She wore sunglasses all the time, and put filters on her computer screen to dim the incoming light. Sometimes people joked that she looked like a drug dealer, wearing sunglasses both indoors and at night. In addition, she found it very difficult to think clearly and stay focused.
She wanted to understand more, but was intrigued by the approach and intuitively knew that this was the right approach for her. Immediately, Cynthia applied the methods that I described in painstaking detail, including: Many markers of her overall health started improving right away, and her ability to control blood sugar improved as a result. Weight Loss In March of Cynthia weighed pounds.
She looks incredible and feels better than she has ever felt. Over the course of the next month, her fasting blood sugar values came down predictably and reliably. Within a few weeks of eating a low-fat high-carb diet, she began backing off on her daily dose in order to prevent low blood sugars. No More Insulin Cynthia started using insulin inin order to reduce her blood sugars beyond that which Metformin could do. Starting in she used 28 units of Novolin N every day, then added 15 units per day of Novolin R in September of Despite this, her blood sugars consistently ran high.
Cynthia is now insulin free. In consultation with her doctor, Cynthia stopped injecting insulin altogether in July of Getting off insulin was an amazing and liberating experience. It is the first time in eleven years of taking drugs, that I actually feel like I am living in a normal body again. Reduced A1c Values When Cynthia was first diagnosed with type 2 diabetes in her hemoglobin A1c value was 9. By Julyher A1c value peaked at Currently, her A1c value is the lowest it has ever been sinceat 7.
Even though her A1c remains elevated from the ideal upper limit of 6. I am very confident that within the next months her A1c values will be less than 6.