The Diabetes Code. Dr. Jason Fung
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Fatty liver disease
NON-ALCOHOLIC FATTY liver disease (NAFLD) is defined as the storage and accumulation of excess fat in the form of triglycerides exceeding 5 percent of the total weight of the liver. This condition can be detected using an ultrasound to examine the abdomen. When this excess fat causes damage to the liver tissue, which can be revealed through standard blood tests, it is called non-alcoholic steatohepatitis (NASH). Current estimates suggest that NAFLD affects 30 percent and NASH 5 percent of the U.S. population; both are important causes of liver cirrhosis (irreversible scarring of the liver).21
NAFLD is virtually non-existent in recent-onset type 1 diabetes. By contrast, the incidence in type 2 diabetes is estimated at upwards of 75 percent. The central role of fatty liver is more fully explained in chapter 7.
Infections
DIABETICS ARE MORE prone to all types of infections, which are caused by foreign organisms invading and multiplying in the body. Not only are they more susceptible to many types of bacterial and fungal infections than nondiabetics, the effects also tend to be more serious. For example, diabetics have a four- to fivefold higher risk of developing a serious kidney infection.22 All types of fungal infections, including thrush, vaginal yeast infections, fungal infections of the nails, and athlete’s foot, are more common in diabetic patients.
Among the most serious infections for diabetics are those involving the feet. Despite adequate blood glucose control, 15 percent of all diabetic patients will develop non-healing foot wounds during their lifetime. Infections in these wounds often involve multiple microorganisms, making broad-spectrum antibiotic treatment necessary. However, the decreased blood circulation associated with PVD (see above) contributes to the poor wound healing. As a result, diabetics have a fifteen-fold increased risk of lower-limb amputation, and account for over 50 percent of the amputations done in the United States, excluding accidents. It is estimated that each of these cases of infected diabetic foot ulcers costs upwards of $25,000 to treat.23
There are many contributing factors to the higher rates of infection. High blood glucose may impair the immune system. As well, poor blood circulation decreases the ability of infection-fighting white blood cells to reach all parts of the body.
Skin and nail conditions
NUMEROUS SKIN AND nail conditions are linked to diabetes. Generally, they are more of an aesthetic concern than a medical one; however, they often indicate the underlying serious condition of diabetes, which requires medical management.
Acanthosis nigricans is a gray-black, velvety thickening of the skin, particularly around the neck and in body folds, caused by high insulin levels. Diabetic dermopathy, also called shin spots, are often found on the lower extremities as dark, finely scaled lesions. Skin tags are soft protrusions of skin often found on the eyelids, neck, and armpits. Over 25 percent of patients with skin tags have diabetes.24
Nail problems are also common in diabetic patients, particularly fungal infections. The nails may become yellowy-brown, thicken, and separate from the nail bed (onycholysis).
Erectile dysfunction
COMUNITY-BASED POPULATION studies of males aged 39–70 years found that the prevalence of impotence ranges between 10 and 50 percent. Diabetes is a key risk factor, increasing the risk of erectile dysfunction more than threefold and afflicting patients at a younger age than usual. Poor blood circulation in diabetics is the likely reason for this increased risk. The risk of erectile dysfunction also increases with age and severity of insulin resistance, with an estimated 50–60 percent of diabetic men above the age of 50 having this problem.25
Polycystic ovarian syndrome
AN IMBALANCE OF the hormones can cause some women to develop cysts (benign masses) on the ovaries. This condition, called polycystic ovarian syndrome (PCOS), is characterized by irregular menstrual cycles, evidence of excessive testosterone, and the presence of cysts (usually detected by ultrasound). PCOS patients share many of the same characteristics as type 2 diabetics, including obesity, high blood pressure, high cholesterol, and insulin resistance. PCOS is caused by elevated insulin resistance26 and increases the risk of developing type 2 diabetes three-to fivefold in young women.
TREAT THE CAUSE, NOT THE SYMPTOMS
WHEREAS MOST DISEASES are limited to a single organ system, diabetes affects every organ in multiple ways. As a result, it is the leading cause of blindness. It is the leading cause of kidney failure. It is the leading cause of heart disease. It is the leading cause of stroke. It is the leading cause of amputations. It is the leading cause of dementia. It is the leading cause of infertility. It is the leading cause of nerve damage.
But the perplexing question is why these problems are getting worse, not better, even centuries after the disease was first described. As our understanding of diabetes increases, we expect that complications should decrease. But they don’t. If the situation is getting worse, then the only logical explanation is that our understanding and treatment of type 2 diabetes is fundamentally flawed.
We focus obsessively on lowering blood glucose. But high blood glucose is only the symptom, not the cause. The root cause of the hyperglycemia in type 2 diabetes is high insulin resistance. Until we address that root cause, insulin resistance, the epidemic of type 2 diabetes and all of its associated complications will continue to get worse.
We need to start again. What causes type 2 diabetes? What causes insulin resistance and how can we reverse it? Obviously, obesity plays a large role. We must begin with the aetiology of obesity.
SIMON
When he came to the Intensive Dietary Management (IDM) program, Simon, 66, weighed 267 pounds, with a waist circumference of 135 cm and a BMI of 43. He had been diagnosed with type 2 diabetes eight years earlier and was taking the medications sitagliptin, metformin, and glicizide to control his blood glucose. In addition, he had a history of high blood pressure and part of one kidney had been removed because of cancer.
We counseled him on a low-carbohydrate, healthy-fat diet and suggested that he start fasting for 24 hours, three times per week. Within six months, he was down to a single medication, canagliflozin, which he continued taking for a period of time to help with weight loss. After another year, we discontinued this medication as Simon’s weight and blood glucose had significantly improved. He has not needed any medications since.
At his last checkup, Simon’s hemoglobin A1C was 5.9%, which is considered nondiabetic, and he had maintained a 45-pound weight loss for two years and counting. Today, he is ecstatic about the change in his overall health. He has gone from wearing a size 46 pant to a 40, and the type 2 diabetes, which he believed was a lifelong disease, has completely reversed. Simon continues to follow a low-carbohydrate diet and fasts once or twice per week for 24 hours.
BRIDGET
When we first met Bridget, 62, she had a ten-year history of type 2 diabetes, chronic kidney disease, and high blood pressure. She was severely insulin resistant, requiring a total of 210 units of insulin every day to keep her blood glucose under control. She weighed 325 pounds, with a waist size of 147 cm and a BMI of 54.1.
Determined to get off insulin, she started with a seven-day fast but felt so well and so empowered that she continued for another two weeks. By the end of the 21 days, she had not only stopped all her insulin but required no diabetic medications at all. To maintain her weight loss, she switched from fasting continuously to fasting for 24 to 36 hours every other day, and she resumed taking dapagliflozin to help control her weight. During this time her A1C was 6.8%, which was actually better than when she was taking insulin.
Before starting the IDM program, Bridget had very low energy levels and could barely make it into my office