The Science Behind It

Are Brown Eggs Healthier than White Eggs?

And if so, what about blue or green eggs???

What is behind it? Many people believe that brown eggs are healthier than white eggs. While brown bread and brown rice are usually better for you than white bread and white rice, this is not true for eggs. Like dogs or cats (or almost any other domestic animal), there are different breeds of chicken (there are well over 100 breeds). The colour of the shell is determined by the breed of the hen. Most of the chickens that produce eggs for grocery stores are Leghorns, which lay white eggs, but chicken eggs can also be light to dark brown, blue, green, and even pink. And it doesn’t even have to be Easter.


What does the Science Say? All eggs start off white when they are still in the hen and
pigments called porphyrins get added before they are laid. The pigment tints the whole shell and doesn’t just sit on the surface.  Porphyrin is the same pigment that makes the red blood cells red. In chickens that lay brown eggs, the pigment is called protoporphyrin and comes from the hemoglobin in the blood. Araucanas are one of the few breeds that lays blue eggs, and the blue pigment is called oocyanin. It gets produced by the liver. Which pigment goes into the shell is determined genetically and crossing a brown egg layer with a blue egg layer produces hens that lay green eggs.

The take home message. Unless you eat the shell, the nutritional value of eggs depends on what is inside, and that depends on the bird’s diet, not genetics.  Free-range eggs are in fact better for you than commercial eggs, because free chickens eat a better diet.
Once thought to increase LDL cholesterol in your blood (which is bad), experts now say that eggs are good for you. The connection between the cholesterol you eat and what’s in your blood is not as clear cut as we once thought so eating cholesterol does not automatically turn into blood cholesterol. In fact, they are one of the few foods that contains nearly every nutrient we need.

Ovaries Key to Longevity. Sorry, guys. Wrong pair.


We’ve known for some time that on average, women live longer than men. Here’s a theory for why.

photo: (C) 2007 K.Becker

What is behind it? How do you live to be 100? When researchers compared Rottweilers that had lived to be at least 13 years old (their average lifespan is 9) they found that “female Rottweilers that kept their ovaries for at least six years were four times more likely reach exceptional longevity” than those who had been spayed before they were 4. When it comes to people, women are more likely to reach 100 than men – 4 times more likely in fact. But when they looked at women who lost their ovaries before they were 50 they lost the usual female survival advantage. In other words their life expectancy became the same as men.

What does the Science Say? Clearly many issues are involved in aging, but the ovaries are more important to women’s health than we thought. We don’t yet know enough about the science of aging, and it is time to ask some new questions about the processes that influence the rate of aging. Postmenopausal women have the same rates of cardiovascular disease as men, and women who have their ovaries removed before age 50 do too. Curiously, the researchers also found that removing the ovaries before menopause increases the risk of dying from lung cancer. Go figure.

The take home message. Doctors used to remove people’s tonsils to avoid serious throat infections but we have since discovered that tonsils actually play a role in preventing infections. Many doctors tell women to have their ovaries removed when they’re done having kids because it helps prevent breast and ovarian cancer. Now it seems that ovaries play a role in women’s health that goes beyond reproduction, in ways we don’t understand. The message here is: don’t have anything removed that doesn’t really need to be. (Note: Women with a family history of breast or ovarian cancer should talk with their doctor about the issues of having their ovaries removed.)

I wonder if there is something we can learn from this to benefit aging in men?

More info: Center For Exceptional Longevity Studies

‘Clan of the Cave Bear’ is Not Entirely Fiction

Ancestral Modern Humans and Neandertals Might Have Had Children Together. (A Draft Sequence of the Neandertal Genome in Science (2010) 328: 710-722)

What’s behind it?
Scientists keep track of different organisms by giving them strategic names.  You might recall the mnemonic “King Philip Cried Out For Goodness Sake” to remember kingdom, phylum, class, order, family, genus, and species.  Organisms sharing the same phylum are considered to be more related than those that only share the same kingdom, and only if you are members of the same species are you similar enough to mate and have children.  There’s much debate about the proper scientific name for neandertals:  are they ‘Homo neanderthalensis’ or ‘Homo sapiens (subspecies) neanderthalensis’?  If the former, they are considered a separate species.  If the latter, they could interbreed to have children, just as Jean Aule stated in her now-classic book series “Clan of the Cave Bear“.  Currently at the Smithsonian Institute in Washington D.C., there’s a new exhibit on Human Origins that insists on the label “Homo neanderthalensis” for the neandertal group – meaning they’re a different species from us.  Are they right?

What does the science say?
Scientists were able to sequence DNA taken from three neandertal fossils and compared it to five present-day humans from different parts of the world.  A group of genes that are inherited only through the mother show that neandertals as a whole were not simply an ancestral group leading to modern humans: we didn’t evolve through a “Neandertal Phase” of evolution nor are they an isolated offshoot from the evolutionary tree.  Perhaps they were a different group of humans.  Despite being different, there are several genes that suggest contribution of genes from neandertal to anatomically modern humans of Eurasian lineage, but not for other groups of anatomically modern humans.

The take home message:
This means that if you’ve got a European background, there’s genetic evidence for a great (great, great,…, great) grandfather of you who was a card-carrying neandertal (well, they didn’t have paper, cards or writing, so that’s  quite a stretch).  The species concept as described here is rather oversimplified.  Some organisms are different species but on occasion breed and have young together.  You might ask is “were neandertals the same species as our modern human ancestors?”  Why did only some of us get only a few of their genes if they mated together?

Fighting Crime with Videogames

Examine the crime scene to seek the truth.

image: game: Crime Scene – The Game (for DS)
categories: science, technology, forensic science

The ability to recreate a crime scene as a virtual world may change how forensic scientists collaborate.

What is behind it? Forensic science has changed a lot in recent years but the way the forensic scientists work has not. Now, researchers at North Carolina State University are using the Unity game engine to build a tool to let Crime Scene Investigators (CSIs) work together in a virtual world. They’ll be able to take a 3D scan of a crime scene and re-create it in a game world, complete with avatars they can use to act out different scenarios. Just like on Bones, they’ll be able to try out different ideas about how the crime was committed to see if it fits the evidence.

What does the Science Say? The Scientific Method is about developing a theory, designing a way to test that theory, and then carrying out those tests to see if they could be right. When we are dealing with crimes, we are often also dealing with things that are dangerous. Until now, forensic scientists had limited abilities to re-create crime scenes. For example, it just isn’t practical to set up a live experiment to test out a theory about how someone was killed, or to shut down a large museum to test a theory about a theft there. However, we can do this in a virtual world, and with the ability to scan an actual crime scene we can increase the accuracy of the mock-up and thereby increase our confidence that we are testing something realistically.

The take home message:
Videogame technology has many applications beyond entertainment. Serious games have become a new way to communicate and learn. Videogames are now used for everything from military recruitment to health, social change, advertising and politics. We are only just starting to understand how and what people learn in video games, and you can expect to see games being used for serious purposes like CSIs more and more.

Coke as addictive as Coke!?

The same brain processes behind drug addiction can also explain your craving for triple-cheese meat-lovers pizza.

What’s behind it? A recent study has shown that the brain pathways involved in forming addictions to drugs are the same ones involved in overeating high-fat/high-calorie or “junk food”. Our brains are just as capable of developing addictions to Twinkies as they are to cocaine. Obesity is growing to become a major health crisis, particularly for the youngest generation. Understanding how our brains react to junk food can help us figure out why we repeatedly decide to binge on Big Macs. But can we really become dependent on our junk food fix?

What does the science say? There are specific parts of our brains that are called “reward” pathways. Essentially it’s the way your brain makes sure you repeat behaviours – it “rewards” you with a pleasurable feeling for your good work. Your typical drugs of addiction like heroine and cocaine activate these pathways and over time cause you to need more and more of these drugs to get that “reward”. You also can start to develop serious negative side-effects until you get your fix. This study says that junk food addiction also acts through these same pathways. The animals in the study easily became addicted to a diet of cheesecake, bacon and sausage-like items, and they continued to overeat even when anticipating receiving electric shocks.

The take home message: Your Mom is right – having unlimited access to junk food can be harmful. It now seems that our chocolate bar habit can develop into an addiction, one we may have serious trouble fighting. We tell kids about the dangers of drugs – do we now include cheesecake and bacon in our pamphlets? Food for thought.

Tweet of the Week, March 20

All-Natural Doesn’t Mean All-Safe

Some vegetarians love animals; others just hate plants H/T @deborahblum: Psst. Plants are out to kill you. 10/03/17

What is Behind It: It sometimes seems like I hear the benefits of all-natural things everywhere.  The kid on the commercial says that his ice-cream is “Naaatural, cuz’ it comes from Nature.”  People don’t want things in their food that they can’t pronounce.  Cleaning products are advertised as “chemical free”, so people who are afraid of chemicals will want them.  The problem is, it is impossible to avoid chemicals.  Everything you touch, eat, breath or are is made of chemicals.

What Does the Science Say: The link this week is to a blog about some poisonous plants people have in their homes.  Peace Lilies, Poinsettias and Holly regularly send people to the hospital.  Even some foods, if prepared improperly or eaten excessively have enough poisonous chemicals to make you ill.  Spinach, rhubarb, and beets all have oxalate, the chemical that makes Peace Lilies poisionous.  Oxalate is dangerous, no matter where it comes from, because it pulls the calcium out of your blood.  Without calcium, nerves and muscles won’t work, and those are kind of important.

The Take Home Message: Just because a chemist makes something doesn’t make it harmful, and just because a chemical comes from the earth doesn’t make it healthy.  Poisons were around long before chemists, and chemists make lots of chemicals you depend on every day.  People sometimes claim that some drugs are safe because they’re natural.  Just because the earth made it doesn’t mean it is safe.  By that argument, strychnine is just fine because it comes from a seed.

Tweet of the Week, March 12, 2010

Laser beams to the head can (maybe) fix what’s wrong

RT @stevesilberman Headline du jour: Gold Nanoparticles and Lasers Kill Brain Parasite That Causes “Crazy Cat Lady” Syndrome 2010/03/09

What is behind it? A parasite that infects rats and cats can also infect cat owners and cause an illness called Toxoplasmosis.  Toxoplasma Gondii, a single-celled creature that lives in cats can be passed on to animals (including us) that come in contact with cat feces.  The parasite affects an infected rat’s brain, and causes the rat to find a cat and get themselves eaten.  The reaction in people is a bit less extreme.  There have been studies that show a link between Toxoplasmosis in humans and psychiatric disorders like anxiety, depression and schizophrenia.  Generally though, for people with a healthy immune system, Toxoplasmosis only makes them feel like they have the flu.

What does the Science say? Researchers in Australia have found a way to make teeny-tiny pieces of gold stick to toxoplasma gondii.  The plan is to shoot the gold with a laser that can pass through body tissue harmlessly.  The gold would absorb the laser energy, heat up, and fry the critter it is attached to.   Since 15% of Americans have Toxoplamosis, a new treatment would be nice.

The take home message. The new science achievement in this story is the ability to attach gold nanoparticles to parasites.  Science has known for a while that shooting gold particles with a laser causes them to get super hot.  Two questions remain.  Can they find the right type of laser to go through the body harmlessly and still heat up the gold?  And can they convince the person down the street with two dozen cats that lasers and being injected with gold particles is a good idea?

Tweet of the Week, March 5, 2010

Marijuana Use Causes Psychosis (Or Does it?)

Psychosis may be a long term effect of smoking pot. Smoking pot may be self-medication for psychosis. 2010/03/02

What is behind it? A recent study shows that people who have used marijuana for several years have a higher than normal chance of also having trouble recognizing what is real.  Symptoms of psychosis, such as hallucinations and delusions, showed up twice as often in people who had used marijuana for six years or more.  Anyone familiar with TV sitcoms showing pot-smokers is not surprised at the correlation and headlines shout that pot causes psychosis.

What does the Science Say? The study shows that pot-smoking and psychosis often go together.  They are correlated.  It doesn’t show that pot causes the psychosis.  In fact, it may be the other way around.  Someone who is prone to psychosis might feel more normal when using pot and end up using it more often than other people as a form of self-medication.

The take home message: People, even the media, often jump to conclusions.  Just because things go together (correlation) doesn’t mean that one causes the other (causation).  It is easy to assume that smoking pot turns otherwise normal people into someone like Leo from That 70’s Show.  We can’t rule out, however, that maybe Leo tokes up because he was losing his connection to reality already.