Brain food

newscientist.com/ eat-your-way-to-dementia

Diabetes of brain and body

Type 1: Only about 5 per cent of people with diabetes have type 1, also called juvenile diabetes, which is typically diagnosed in children and young adults. It starts when an autoimmune response destroys the insulin-producing cells in the pancreas, meaning the body can no longer regulate levels of blood sugar. Insulin therapy helps these individuals lead a healthy life.
Type 2: Most people with diabetes have type 2. Here, the pancreas either does not produce enough insulin or the muscle, liver and fat cells ignore the insulin and fail to suck excess sugar from the blood. This can lead to both high insulin levels and high blood sugar - the hallmarks of type 2 - which can raise the risk of heart disease, stroke, blindness, nerve damage and amputation. Being overweight, particularly if you have excess abdominal fat, increases your risk of developing type 2 diabetes.
Type 3: This controversial new category, coined by Suzanne de la Monte, refers to Alzheimer's disease, which she and a growing number of other researchers believe arises when brain tissue becomes resistant to insulin. In that sense it is like type 2 but primarily concerns the brain.

Food for thought

Brain food isn't just an expression. Recent studies have revealed that consuming a lot of foods high in saturated fat and sugar or anything with a high glycaemic index are bad for your brain because they keep your insulin levels high.
A recent study from the University of California, Los Angeles, showed that rats consuming water laced with high-fructose corn syrup, a sweetener in soft drinks, condiments and many processed foods, had learning and memory problems after just six weeks, and their brain tissue became less responsive to insulin.
But certain dishes may offer some protection against these effects. Rats consuming high-fructose corn syrup water alongside omega-3-fatty acids from flaxseed oil seemed to escape the cognitive problems the other group encountered (Journal of Physiology, vol 590, p 2485). Omega-3 acids are also found in oily fish.
There is also some tentative evidence that certain compounds called flavonoids, found in tea, red wine and dark chocolate, can reduce the risk of dementia. All of which may explain why the Mediterranean diet is associated with less cognitive decline, dementia and Alzheimer's disease. This diet is known to be rich in fish and vegetable oils, non-starchy vegetables, low glycaemic fruits, less added sugar and a moderate helping of wine (Current Alzheimer Research, vol 8, p 520).