By Dr. Frank Sabatino

Blood sugar (glucose) control is one of the most important functions of the body. Only plants can take the direct energy of the sun and produce glucose that is transformed  and stored as energy reserves in the energy factories of your cells (mitochondria). The body is always concerned that we have enough glucose in our blood to meet our energy needs. When you eat plants, the glucose in your blood satisfies these energy needs, especially for brain and red blood cells that are the primary glucose-dependent cells in the body. (1) The brain is only 2% of your body weight , but requires 20% of your energy!

The body is devoted to the idea of always keeping our blood sugar level within a well-defined, healthy range of normal. If the blood sugar level goes up above this healthy range, it becomes one of the most toxic, aging influences known to man. Just think about the incredible damage and disease that can occur in diabetics with chronic high blood sugar: devastating heart and kidney damage, loss of eyesight, and amputation of limbs. So, the body is tasked with the challenge of keeping blood sugar within a normal range.

To accomplish the task, the body releases the hormone insulin from small islands of cells in the pancreas into the bloodstream. Insulin circulates and attaches to special proteins (receptors) on the surface of cells. The insulin receptors are designed to exactly match the shape of insulin, like the lock on a door matches its key. When insulin attaches to its receptors, a signaling pathway inside the cells opens the door in the cell membrane and allows the glucose in the blood to enter the cell. This regulation enables blood sugar to be effectively utilized to satisfy current energy needs and be stored for future needs. 

Typically, normal dietary intake of carbohydrates exceeds the needs of the cells, and additional glucose can go into liver and muscle cells where it is stored like a savings account, as an energy reserve, for a future time of need. In a time of stress or increased activity, when we need additional energy, stored glucose stored can be mobilized back into the bloodstream and made available for energy demands.

The primary destination of excess dietary sugar is the skeletal muscles that move the body. (2) Think about all the activity that the body has to perform on a daily basis and all the energy our muscles have to exert to accomplish this action. In fact, in the fed state when the body is responding to the hormone insulin, skeletal muscle has the greatest impact on the removal of excess sugar from the blood, accounting for as much as 60-70% of glucose removal. (3) The liver accounts for the smallest fraction of excess sugar removal. (4)

Several nutrition and lifestyle factors have a significant impact on insulin function. If you eat a high fat diet, especially the saturated and processed fats in animal and junk foods, fat can be rapidly absorbed into muscle cells, basically taking up space in these cells and making them less available for the needed entry and storage of sugar (glucose). The excessive fat in muscle cells will also alter the receptors for insulin, making insulin less able to attach. This interference with insulin attachment, and the blockage of insulin’s ability to effectively promote sugar entry into  cells, is calledinsulin resistance. Other factors also promote insulin resistance, including aging, fatness, decreased exercise, chronic stress, and sleep deficiency. 

To visualize insulin resistance more clearly, imagine changing a lock on a door, then trying to open the door by sticking the old key in the new lock. It wouldn’t work, of course, and you would not be able to open the door. These nutrition and lifestyle factors change the ability of cells to access blood sugar (glucose) by altering the cells’ “locks”, so that insulin can no longer open the cell “door” for sugar entry. As cells resist the attachment of insulin, circulating sugar cannot enter muscle and liver cells effectively, and the glucose (sugar) levels in the blood will continue to increase, posing a potentially toxic threat to the body. Since sugar can not enter cells effectively, cells become starved for sugar and energy, increasing the craving for sugar. 

When there is insulin resistance and blood sugar levels rise, the body begins to act as if there’s an insulin deficiency. It signals the pancreas to make more and more insulin to help drive the excess glucose into the cells. In fact, it can produce and release as much as two to three times more insulin than is found in a lean, young, healthy person. It has been known since the 1960s that the excessive release of insulin is a characteristic feature of obesity and weight gain.¹Elevated levels of insulin in the blood (hyperinsulinemia) increase the risk of heart disease, brain damage, and cancer. Elevated insulin also produces increased hunger, increased food intake, and a heightened perception of the pleasantness of sweet taste and processed foods loaded with refined sugar.⁽⁴⁾

When insulin is not working effectively, this cycle continues chronically, and sugar continues to stay elevated despite increasing insulin levels. Type 2 diabetes can develop as a result. For years, the traditional medical view has incorrectly portrayed this purely as a sugar problem telling people to avoid even healthy carbohydrate plant food while advocating high-fat, high protein animal products as the solution, only reinforcing the true role of high fat as a major cause of insulin resistance. The good news is that it is a fixable problem. To avoid this, and to effectively treat it, it is essential to adopt appropriate lifestyle changes, including a high-fiber, low-fat, high-carbohydrate, plant-exclusive approach to nutrition, consistent activity, better sleep and stress reduction.

This situation leads to a profound example of the wisdom of the body. It’s important to note that fat provides us with 9 calories of energy per gram compared to protein and carbohydrates which only provide 4 calories per gram. That’s why eating a lot of fat can remarkably increase calorie density and weight gain. However, it also means that fat will provide the most abundant reserve of  potential energy for every gram that you store in your fat tissue. So, when the body is confronted with elevated blood sugar, it converts this toxic threat into the most energy-efficient material that it can possibly create—fat—and stores it in your fat cells. (5)(6)

The stored body fat has a purpose: it supplies the body with significant energy reserves that it is able to access and utilize for additional energy, if and when needed. Unfortunately, many of us have stored more of this material than we can ever use in a lifetime. To put a positive spin on it, you can make the case that the pandemic of obesity is fundamentally a direct effect of the body’s wise attempt to protect itself against the toxic elevation of blood sugar.

In addition to promoting potential weight gain, elevated blood sugar is a form of toxic chemical stress on the body that provokes the glands of stress, the adrenal glands, to elicit a fight-or-flight stress response and release the hormone cortisol to mediate this response. Unfortunately, cortisol has an affinity, a love affair, with fat cells in your abdominal region and can increase abdominal belly fat, the riskiest weight gain of all, significantly increasing the risks of heart disease and diabetes.

Cortisol has a direct impact on the fat-making enzyme lipoprotein lipase. This enzyme is located in small capillary beds in fat tissue, especially in visceral fat around the abdomen. It helps metabolize triglycerides in lipoproteins into a pool of circulating fatty acids that increase fat production and storage. Not only does cortisol directly increase the activity of lipoprotein lipase, but cortisol can also directly access and affect the genetic machinery of your cells to stimulate the production of it. This lends credence to the important role of stress management in general, and toxic stress reduction in particular, in fat and weight gain.

This information strongly suggests that ongoing insulin resistance may be the most significant hormonal imbalance of many people with weight and other health problems. Unless insulin resistance is healed over time, it is virtually impossible to handle sugar in a manner that will allow you to keep your weight under control. But the exciting news is that a simple whole food plant focused diet, together with consistent exercise, improved sleep and stress management can heal and reverse insulin resistance and dramatically improve a diversity of health promoting metabolic functions.

References

1. Björntorp P, Brodoff BN. Obesity. Philadelphia, PA: JB Lippincott Co.; 1992: Chapter 40.
2. DeFronzo RA, Ferrannini E, Hendler R, Felig P, Wahren J. Regulation of splanchnic and peripheral glucose uptake by insulin and hyperglycemia in man. Diabetes. 1983;32(1):35-45. doi:10.2337/diab.32.1.35
3. Björntorp P, Sjöström L. Carbohydrate storage in man: speculations and some quantitative considerations. Metabolism. 1978;27(12 Suppl 2):1853-1865. doi:10.1016/s0026-0495(78)80004-3
4. Rodin J. Insulin levels, hunger, and food intake: an example of feedback loops in body weight regulation. Health Psychol. 1985;4(1):1-24. doi:10.1037//0278-6133.4.1.1
5. Jackson RA, Roshania RD, Hawa MI, Sim BM, DiSilvio L. Impact of glucose ingestion on hepatic and peripheral glucose metabolism in man: an analysis based on simultaneous use of the forearm and double isotope techniques. J Clin Endocrinol Metab. 1986;63(3):541-549. doi:10.1210/jcem-63-3-541

Foley JE, Thuillez P, Lillioja S, Zawadzki J, Bogardus C. Insulin sensitivity in adipocytes from subjects with varying degrees of glucose tolerance. Am J Physiol. 1986;251(3 Pt 1):E306-E310. doi:10.1152/ajpendo.1986.251.3.E306