Here's a finding so, well, weird that you may have forgotten about it: Obesity can spread from one person to another like a fad or the flu.

If one spouse is obese, the other is 37 percent more likely to blow up within two to four years. Brothers affect brothers, friends affect friends - even when living on different continents.

The research - led by Harvard Medical School, published in the prestigious New England Journal of Medicine and involving more than 12,000 people tracked over 32 years - was lauded as brilliant, stunning and groundbreaking.

Other head-scratchers:

Diet soda is just as bad for you as regular. Drinking as little as one can a day of either type is associated with a 44 percent higher risk of developing metabolic syndrome (a predictor of both diabetes and heart disease), and a 31 percent higher risk of obesity. Researchers aren't sure why.

Working the graveyard shift is a probable cause of cancer. Scientists suspect the reason is that melatonin, a tumor-suppressing hormone, is normally produced at night but the trigger goes awry when overnight work disrupts the body's biological clock.

Most people are sexually active well into their 70s, and even when sex stops, it's mostly due to lack of a partner. "You have fewer orgasms," said a 78-year-old sex educator not in the study, "but they're more appreciated and more enjoyed." - Don Sapatkin