How Much Radiation Exposure Occurs with a CT Scan? X-ray? Sunlight?

A common concern now is how much radiation exposure occurs with common radiological testing such as x-rays and CT scans, especially given the small increased risk of cancer with accumulated exposure over years. Of note, ultrasounds and MRI scans do not emit radiation. MRI scans use magnets while ultrasounds use sound waves in order to obtain imaging information. So, here's a chart comparing such tests with common environmental radiation exposure such as sunlight. Information taken fro…

Continue Reading

Why Do Humans Have Weak Sense of Smell

Compared to nearly all other animals, humans have the weakest sense of smell. You would think that humans and our closest evolutionary cousins (chimpanzees, apes, etc) would have similar sense of smell, but humans still have a much weaker olfactory sense. Why might that be? Well, research from Karolinska Institutet have discovered that humans are the ONLY mammals whereby no new neurons are formed in the olfactory bulb after birth. Or if there is any, it is VERY little. In all other …

Continue Reading