Latest articles by Rachael Rettner
What are the systems of the body? Fast facts about the human body and how it works
Reference Learn all about the human body's many systems and some of its individual organs, both vital and vestigial.
What's the rarest blood type?
Blood typing is particularly important for blood transfusions.
RSV: Symptoms, treatments, antibodies and vaccines
In healthy children and adults, RSV typically causes mild, cold-like symptoms, but it can cause more serious disease in infants, young kids and older people.
Coronavirus variants: Facts about omicron, delta and other SARS-CoV-2 mutants
Here's a look at the science behind SARS-CoV-2 variants, including the now-dominant omicron and its many defunct relatives.
Musician's head injury triggered rare synesthesia, causing him to 'see' music
A man's head injury resulted in a rare neurological condition that caused him to "see" music, and simultaneously, he became more creative.
Most melatonin gummies have higher doses than what's on the label
A new analysis reveals that most melatonin gummies sold in the U.S. contain more of the hormone than noted on their labels.
Fatal drug overdoses have quadrupled in US seniors
The rate of fatal drug overdoses among U.S. seniors has quadrupled in the last 20 years.
What is DNA?
DNA is a molecule that contains the instructions an organism needs to develop, live and reproduce.
Breast cancer: Symptoms, treatment and prevention
Breast cancer is the second most common cancer among women in the United States.
Italian woman's rare 'foreign accent syndrome' caused her to sound Canadian
A woman's strange case of "foreign accent syndrome" left doctors unsure of its cause.
Insomnia: Causes, symptoms and treatment
Insomnia is a sleep disorder that makes it difficult to fall or stay asleep.
Sleep apnea: Symptoms, causes and treatments
Sleep apnea is a condition in which people experience pauses in breathing, or shallow breathing, during sleep.
1 billion teens and young adults risk hearing loss from listening devices
More than one billion teens and young adults worldwide may be at risk for hearing loss, a new review study suggests.
Powerful 8.1-magnitude earthquake off New Zealand triggers tsunami warnings
The powerful earthquake occurred at 8:28 a.m. local time near New Zealand's Kermadec Islands.
Weight Loss Triggered When One Fat-Absorption Gene Is Blocked
Scientists have discovered a chain of events occurring inside cells that control the amount of fat the body takes up.
The flu (influenza): Causes, symptoms and treatment
The flu (short for influenza) is a respiratory virus that affects the throat, nose, bronchi and, sometimes, the lungs.
Heartbeats Hint at Personality Traits
Aspects of our personality can be revealed in a heartbeat, literally.
Men's and Women's Personalities: Worlds Apart, or Not So Different?
Men and women's personalities are worlds apart, a new study says, but other researchers say it ain't so.
Some Personality Traits Affect How You Smell
It may be possible to get a hint of an individual's personality through his or her scent.
Men's and Women's Personalities: World's Apart, or Not So Different?
Men and women's personalities are worlds apart, a new study says, but other researchers say it ain't so.
'Helicopter' Parents Have Neurotic Kids, Study Suggests
Children with so-called "helicopter parents" are more likely to be dependent, neurotic and less open, a new study finds.
Nearly 50% in US Believe in Medical Conspiracy Theories
About half of Americans agree with at least one medical conspiracy theory, a new study suggests.
Vitamins from Food — Not Supplements — Linked with Longer Life
Certain vitamins and minerals are linked with a lower risk of early death, but only if the nutrients come from food, not supplements.
