The radiation exposure is extremely small, and the cancer risk has been called "truly trivial."

Safe is a tricky, eye-of-the-beholder word and concept. If safe means absolutely zero risk, then the answer to the "Are they safe?" question for scanners that use low-level x-rays is probably no. But if safe means a very small increase in risk — so small that a reasonable person shouldn't be seriously concerned about it — then the answer seems to be yes, they are safe, according to a persuasive article published in 2011 in Archives of Internal Medicine.

Two types of full-body scanners The ...

Statins and lower cholesterol … According to the National Center for Health Statistics (NCHS), the percentage of Americans ages 45 and older taking a statin drug jumped from 2% in 1988–94 to 25% in 2005–08. There are roughly 117 million Americans over age 45, so that means there are almost 29 million statin users, or the equivalent of the entire populations of Florida and Georgia combined. Here is a graph from the NCHS that shows the increase:

The fact that one in every four Americans older than the mid-40s is taking a statin is really kind of stunning (presuming, of course, ...

The timing and the contents of breakfast make it perhaps the most important meal of the day.

Whether it features soup in Vietnam, biscotti in Italy, or scrambled eggs in the United States, breakfast revs up the body after a night's sleep, giving us energy and nutrients to face the day. Studies suggest that eating breakfast regularly is associated with good health — and that the timing of the meal, as well as what's in it, matters.

Eating first thing As we sleep, chemicals in our bodies are at work digesting food from the previous night. By morning, we are ...

Pharmaceutical pollution doesn't seem to be harming humans yet, but disturbing clues from aquatic life suggest now is the time for preventive action.

Although maybe not as tasty as an ice-cold gulp from a mountain spring, the water that flows through most American kitchen faucets is generally clean, clear, and safe. Approximately 170,000 public water systems are monitored for nearly 80 harmful substances. The prohibited nasties include bacteria, viruses, pesticides, petroleum products, strong acids, and some metals.

But water quality experts and environmental advocates are increasingly concerned about another kind of water pollution: chemicals from prescription drugs and over-the-counter medications ...

Q. There's a lot of publicity about omega-3 fats being beneficial for heart, mind, joints, eyes, and so on. There are over-the-counter products of varying size. So, this is my question: is there a daily upper limit on fish oil consumption?

A. There isn't an official upper limit, but for most people, I'd be inclined to draw the line at a gram — 1,000 milligrams (mg) — of omega-3s from fish oil a day.

One of the main concerns about high omega-3 consumption has been that it could "thin the blood" and thus increase the risk of bleeding and, more ...