With all the publicity about a Type 2 diabetes epidemic, an equally scary rise in rates of Type 1 has been ignored. What is causing the surge in Type 1 diabetes? Does it have anything to do with the Type 2 explosion?
First the numbers. Type 1 diabetes has always existed, but it was rare. According to an exhaustive study by Dr. Edwin A. M. Gale of the University of Bristol, rates of Type 1 were on the order of 4 cases per 100,000 children prior to 1950.
In the early 50’s, Type 1 started increasing at a rate of 2% to 4% a year in the US and Europe. That may not sound like much, but now there are 3–4 cases per 1,000 children in these countries. This increase is actually as sharp as the increase in Type 2. It just started from a much lower point, so it’s still under most people’s radar.
Sometime in the 60’s and 70’s, Asian countries also started experiencing the Type 1 increase, and now most (but not all) countries in the world are seeing it.
It’s still happening. In a June meeting of the American Diabetes Association, researchers reported a 23% rise in Type 1 in the USA over an eight-year period ending in 2009. Prevalence of Type 2 diabetes over the same period increased 21%, the researchers found. So Type 1 is going up even faster than Type 2.
What Causes Type 1?
Type 1 diabetes is considered an “autoimmune” disease. Autoimmunity is present when our immune systems damage and destroy healthy cells. Autoimmunity can hit anywhere in the body. In rheumatoid arthritis, it attacks the joints; in multiple sclerosis it’s the nerves; in lupus, mostly the kidneys. In Type 1 diabetes, the immune system destroys the pancreatic beta cells that produce insulin.
But what causes autoimmunity? We don’t know. Many experts believe it’s the thousands of new chemicals that are constantly added to our environment. Our immune systems get confused and may lose the ability to distinguish harmful invaders from the body’s own tissues.
Interviewed on our Web site, Donna Jackson Nakazawa, author of The Autoimmune Epidemic, said, “There are
We often hear from uninformed people that Type 1 is “genetic,” while Type 2 is caused by “lifestyle.” In reality, Type 2 may have a stronger genetic component than Type 1. Only about 20% of people with Type 1 have a close relative with the disease.
There are genes that predispose people to Type 1, as there are with Type 2. But without exposure to environmental stressors that turn those genes on, people don’t get sick.
Obviously, something happened around 1950 that has turned on more of those autoimmune genes. Not only are more children getting Type 1, but it’s being diagnosed at earlier ages on average, just as Type 2 is hitting younger people.
What’s in the Environment?
There are five leading theories on how environmental change has increased Type 1.
• The “accelerator hypothesis” holds that faster growth in early life is putting stress on beta cells, setting off the autoimmune attack. So diabetes is just an unfortunate side effect of kids’ getting bigger. I doubt this.
• Another theory, the “hygiene hypothesis,” holds that children in a modern society face fewer parasitic, viral, and bacterial invaders, because we’re so clean and use so many antibiotics. “Because it is getting less of a workout, the immune system turns evil on itself,” said Robin Goland, of the Columbia University Medical Center in New York.
There is some evidence for this. According to Dr. Gale, mice exposed to pinworm infections have lower rates of Type 1. People used to get pinworms, too, so perhaps eliminating them is what set off the Type 1 surge. Research is being done on using worms to prevent or treat autoimmune disease.
• Some believe that diabetes increased when people started spending more time indoors. We got less sun so made less vitamin D. Low D levels may lead to autoimmunity. People who live in sunny places tend to get less autoimmune disease than people in higher latitudes and cloudier climates.
• Cow’s milk has been blamed by many. As I wrote here, a particular milk protein, A1 beta-casein, seems to be associated with most cases of Type 1. Perhaps the increased use of cow’s milk has led to the worldwide Type 1 surge.
However, Dr. Gale found that “[22%] of American women breastfed in 1972, rising to 60% in the 1980’s and 1990’s. [But] the incidence of childhood diabetes [increased steadily.]” So maybe it’s not the cows’ fault.
• Environmental chemical pollution seems a top contender. We have been reporting for years on studies showing that air pollution, and exposure to chemicals such as bisphenol Aand phthalates lead to an increased risk of Type 2. Researchers are finding that heavy metals and organic chemicals like dioxins can disrupt the immune system.
These chemicals have already been strongly associated with Type 2, as with Agent Orange, the chemical sprayed by the military on Vietnam. So what I’m wondering is, are the two diseases more closely related than we had thought? In both cases, your genes make you vulnerable, but it’s the environment that sets them off.
To me, it seems the increased loads of starches and sugars people eat now are among the biggest environmental triggers. But the pollution, cow’s milk, and hygiene theories may explain a lot about both types. What do you think? What should we do about it?