Type 1 Diabetes Mellitus occurs when the islet cells of the pancreas that produce insulin are destroyed (usually by antibodies to attack a virus but which incidentally destroy the islet cells). If the islet cells are destroyed, then the individual cannot create insulin. Without insulin the individual will die, and therefore Type 1 diabetics require treatment with insulin in order to live.
Before Dr. Banting (and Best, and Collip and maybe Macleod) created an injectable form of insulin in 1921, Type 1 Diabetes was a virtual death sentence. Parents would often just watch their children wither away and die. Here for instance is a picture of a 3-year-old child before he was given insulin and 3 months after being on insulin.
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| From Lilly Archives |
However, Type 1 diabetes (or the destruction of the pancreatic islet cells that create insulin) only accounts for approximately 5%-10% of diabetics in America. Most Americans with diabetes have Type 2 Diabetes.
Like obesity, Type 2 diabetes has increased dramatically in our country. Here is a nice graphical map from the Centers for Disease Control showing the increase in diabetes diagnoses and how it correlates with obesity.
The initiating insult in Type 2 Diabetes is usually insulin resistance. That means the cells that receive insulin are resistant to the insulin that the pancreas produces.
Some of the most insulin resistant cells of the human body are seen in the visceral fat. Visceral fat is the fat that surrounds the internal organs such as the heart, the liver, the pancreas and the kidneys. This visceral fat creates the central adiposity that can affect so many of us as we gain weight (“the beer belly”).
To counteract this insulin resistance, the pancreas initially produces more insulin in response. Thus early in the disease process (the pre-diabetic phase) the pancreas actually is producing too much insulin. This can occur 20-30 years before an individual is diagnosed with diabetes. The resistance of this visceral fat is often too great, and the pancreas eventually burns out, losing the ability to produce insulin. It’s like a car running out of gas. In fact, by the time most people are diagnosed with Type 2 Diabetes, the pancreas has already lost 50% of its ability to produce insulin.
One of the most effective ways to treat diabetes is likely to prevent it from occurring, particularly during this pre-diabetic phase.A large trial called the Diabetes Prevention Program, enrolled 3,234 individuals who were overweight and had pre-diabetes. The trial duration was nearly 3 years. Some participants received intensive dietary and lifestyle advice with a desire to exercise 150 minutes a week and lose 7% of their body weight, others received a diabetic drug called Metformin (850 mg twice a day) and a third group was the control group, receiving placebo pills and some basic literature on a healthy diet. Participants in the intensive lifestyle program reduced their risk of developing diabetes by 58% (and by 71% in those over 60 years of age). Approximately 5% of individuals in the intensive lifestyle group developed diabetes compared to 11% of the control group. Participants who used Metformin reduced their risk by 31% with 7.8% of individuals developing diabetes compared to 11% of the control group. Keep in mind that over 3 years the people in the Intensive Lifestyle group, only lost approximately 11 lbs.
Type 2 Diabetes Mellitus does not strike all people or groups equally. Individuals of certain races and nationalities often have increased incidence of diabetes. One of the groups with the greatest incidence of Type 2 diabetes is Native Americans that live in southern and central Arizona known as the Pima Indians. The National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) has studied this group for over 30 years. They have a dedicated section on the Pima Indians here.
A study by Schulz et. al compared adult Pima Indians who live in Arizona to the adult Pima Indians who live in Mexico. These individuals have the same genetic heritage but a different lifestyle and different environment with a remarkably different effect on their health.
Of the Pima Indians in America
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| (NIDDK) |
63.8% of males are obese (average BMI of 33.3)
74.8% of females are obese (average BMI of 35.5)
34.2% of males have diabetes
40.8% of females have diabetes
Of the Pima Indians in Mexico
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| (NIDDK) |
6.5% of males are obese (average BMI of 23.8)
19.8% of females are obese (average BMI of 26.3)
5.6% of males have diabetes
8.5% of females have diabetes
The striking difference in diabetes and obesity appears to be related to the different diet and energy activity among the different groups. One could simply state that the Pima Indians in America eat poorly, don't exercise and get diabetes. Yet, there appears to be more. Many different populations and groups may have similar body mass indexes to the Pima Indians in Arizona yet they don't have near the rate of diabetes. In 1962, the geneticist James Neel proposed the "Thrifty Gene" theory. That is, that certain populations are more apt to store energy. When they are working and living in a hard and difficult climate, they need the ability to store energy. This energy can be used during times of difficulty or famine. However, if you place such individuals in an environment where there is little activity and great amounts of nutrient-poor calories, their body will respond by rapidly absorbing calories from the environment.
Personally, I find James Neel's theory appropriately elegant. This ability to store energy may have led to an advantage for the individual who is living in a difficult environment. It allows the individual to survive harsh environments and gives them the ability to store energy for times of famine. Thus, in some respects, the ability to develop diabetes may be a sign of the strong organism -- an organism that can very effectively store energy. This is not "a problem", or "a disease" of the individual. Rather, it almost becomes a measure of a disease of a culture that doesn't respect the individual organism's ability to effectively store energy.
Look at the desert environment in which the Pima Indians have lived for thousands of years. Over generations they have had to develop the ability to survive the harsh climate. To survive, they may have developed this "thrifty gene" to endure months of famine and hardship. However, if you place such an individual in an environment where there are plenty of low quality food choices, then the organism will adapt by rapidly storing this energy as visceral fat.
Perhaps the problem isn't with the individual who has diabetes, per se, but rather the culture or environment that the individual finds him/herself in. It is like taking a Lamborghini and instead of putting in 93-94 octane you put 87 octane mixed with sugar in the gas tank. The Lamborghini, which requires high octane fuel to keep the car at peak performance, may suffer even more from such a concoction than a Ford Pinto that runs on leaded gas. That doesn't mean the Lamborghini is a more "defective" car, it just means that it uses energy very effectively and requires higher quality fuel to run. If one respects the beauty and power of the Lamborghini, then one might try to optimize the fuel that is placed in it.
Other groups can develop Type 2 diabetes very easily. Individuals from South Asia can have very high rates of Type 2 diabetes, up to 4 times the rates of other ethnic groups. As stated in the last post, there is even a South Asian BMI calculator which defines "overweight" as a BMI of 23.1 to 25 and obese a BMI greater than 25. Again, it seems to be related to their ability to store and develop visceral fat that is resistant to insulin.
The risk for all Americans for developing diabetes in their lifetime is approximately 11% by the age 70. However, there are certain genetic traits that rapidly increase that risk. If an individual has a parent that has diabetes, lifetime risk is approximately 33%. If an individual has 2 parents with diabetes, the risk is close to 50%. Again, certain ethnicities have significantly greater rates of diabetes than other groups. But again, it doesn't seem to be simply genetic. There is a strong environmental element as well. The lack of physical activity coupled with often large portion sizes and calories of poor nutritional value can foster a dramatic increase in diabetes, particularly among certain groups. This has led some researchers to conclude that we live in a "diabetogenic culture," particularly for certain groups.
So where does that leave you, dear reader? Do you have diabetes? If not, what is your risk of developing diabetes? Perhaps if your risk is high or if you have pre-diabetes or diabetes, hopefully some of this information can be empowering. If one does have diabetes or is at a high risk, I think it might be best to view oneself as possibly inheriting a body that can store energy very effectively. To maximize its energy storage ability, it will likely be very beneficial to eat a highly nutritious diet and maintain or create an active lifestyle. This is not to say that this is necessarily an easy process. To effectively tap into the power of a body that effectively absorbs energy means that the individual will have to respect its power and often fight the easy temptation to eat a diet high in processed foods and empty calories.
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