Cardiovascular disease (CVD) and diabetes are perhaps the most consequential diseases in America in terms of deaths, economic impacts, and effects on quality of life. Despite intensive efforts and millions of dollars worth of studies, our understanding of CVD and diabetes remains incomplete.
The fine work of Chris Kuzawa from Northwestern University shows how environmental influences during development can cause diabetes. Please complete the reading prior to class. It will also be hard to do the writing project without first doing the reading.
Reading: also on eReserve
1. Kuzawa – Diabetes and Development
There appears to be switch activated in underweight babies that leads to diabetes later in life. Early on, many underweight babies are insulin resistant. Insulin resistance is a pre-diabetic state. In these small babies, less glucose gets metabolized by muscle tissue. As a result, less energy is devoted to growth and building muscles and bones. On the flip side, more glucose is available for other uses ‐ like the brain and perhaps white blood cells.
Kuzawa proposes that because humans have particularly large brains (recall Dr. Trevathan’s lecture) glucose gets diverted to the brain from the rest of the body in times of stress. In this view, insulin resistance feeds the brain.
1) Try answering this: What might be the consequence of slower growth, and higher blood sugar in these infants? Are there situations in which more energy available to the brain or immune system might be helpful?
2) If that is too tough, try this: Large brains appear to have benefits and costs to the developing baby. Try to name three downsides to having a very large brain in an infant. What might be the benefit?
3) Extreme extra credit. Can genetic conflict (recall two lectures ago) have something to do with insulin resistance in an infant?