Dental Floss: Your Daily Biofilm Demolition

We've all heard that flossing should be part of our daily oral hygiene routine, but why?? Less than half of us (in the U.S.) actually follow this recommendation. I suspect* it has something to do with the following:

1) Flossing is fundamentally strange and appears to be more an act of masochism than one of self-care. If a dentist were to describe flossing to someone unfamiliar with the practice it would go something like this: "Now, I want you to take this string and force it between your teeth. Then slide it all the way up into the space between your gum and tooth. Don't worry if you have a mouth full of blood, that will go away after you get used to it. Repeat that for every tooth in your mouth" Ummm, that's supposed to be good for me?

2)  Flossing, from the perspective of the human eye, offers little instant gratification. On occasion, a visible food particle might get removed but mostly there isn't much to see. Should you skip a day, or even a week of flossing, you likely won't notice any difference. Fail to brush your teeth and you'll have retched breath. Skip bathing and soon you'll be oily and stinky. But hey, nobody has to know that you were tired and skipped flossing last night, right? And then you skipped the night after, and the night after...

As you can probably guess, this post is not about why you should never floss. Here's the deal: flossing is actually incredibly important but its daily impact occurs on the microscopic level. With an understanding of this impact, you may learn to appreciate the power of dental floss.

We all have mouths full of bacteria - some are helpful and others can lead to the development of cavities, gum disease, and other oral health maladies. Our teeth are prime real estate for the formation of biofilms, which are communities of bacteria that adhere to surfaces and surround themselves with tough, protective matrices. Just like other organisms, bacteria find safety in numbers and are able to accomplish greater feats as a team than on their own. On a daily basis, biofilms begin to form on your teeth within minutes after brushing. Go ahead, feel your teeth right now - notice that slimy quality they have? That, my friend, is a biofilm referred to as dental plaque. The longer these bacterial communities are left undisturbed, the tougher they become. When we brush, the biofilm foundations are damaged and the bacteria are prevented from advancing too far in their building efforts (do you really want bacteria building sky scrapers and condos on your teeth?). There are crevices in your mouth that a toothbrush can't reach, such as between your gum line. Though you can't see this with your naked eye, flossing is like a dynamite explosion to the plaque taking up residence between your teeth and gums. Without this daily demolition, plaque continues to build up and eventually hardens into dental tartar (also called calculus, but not the kind you learn in math class), which can only be removed by the scraping of  professional dental instruments (a far more terrible and awkward experience than flossing). If not removed, dental plaque and tartar can contribute to a wide array of periodontal disease, not to mention an unsightly and malodorous smile.

There you have it, the truth behind why you really should slide that string between your teeth every day.

*This suspicion is based purely on my personal reflections and observations and is not (to my knowledge) backed by a reputable source of scientific data. If someone would like to turn this into a testable hypothesis, please be my guest.

Your belly is a bacterial bonanza (and that's a good thing)

Get this: it turns out your body is analogous to a planet. A planet inhabited by trillions of microbes (bacteria, archaea, viruses, and fungi)* which add up to comprise 1-3% of your total body mass. That means if you weigh 150 pounds, you are carrying 1.5 - 4.5 pounds of bacteria (and other microorganisms) around with you everywhere you go (as a point of comparison, the average adult human brain weighs 3 pounds). In terms of mass, your cells outweigh those of your microbial inhabitants. But, don't be fooled: microbial cells are much tinier than human cells. You actually have 10 times MORE microbial cells in and on your body than you do human cells. In other words, you are 90% microbial cells. BOOM - that was the sound of my mind (and probably yours) being blown.

Now before you try to swallow a bottle of antibiotics or scrub your skin raw, you should know that you need most of these microbes to survive. Nasty bacteria that cause infection and illness have been giving friendly bacteria a bad reputation - until now! Science is just beginning to unravel the complex relationships between our bodies and the microbes that normally inhabit us. While there are commonalities in the types of bacteria that tend to colonize specific regions of the body, every person's microbial population is unique in its demographics (much like no two cities have identical census data). The types of microbes that call your body home, and the ratio of different species, can affect your health in different ways.

One of the areas of our bodies that is rife with bacteria is, no surprise, our gut.  Studies about gut microbes are beginning to pile up evidence to indicate that these bacteria are no small players. You need bacteria in your digestive tract to produce enzymes for digestion, to aid in vitamin synthesis, and to produce products for your immune system. Your metabolism depends on them! Additionally, the variety and amount of bacteria in your gut can have far-reaching implications. Your gut microbes could play a role in how much you weigh. They might positively or negatively influence your risk for cardiovascular disease. They could affect how efficient your body is at breaking down certain nutrients. Gut microbes may even shift in composition to accommodate alterations in metabolic demands, such as in pregnancy.

Not only are these new findings exciting for the future of science and medicine, they are also paradigm-shifting in how we view metabolism. As we all know, our society tends to place quite a bit of blame on individuals who struggle with obesity: but what if some obese people just have overly efficient gut microbes? Chew on that.

As if all this news isn't wonderfully mind-boggling and curiosity-piquing enough, YOU can actually contribute to the future understanding of how gut microbes affect our well-being: http://www.indiegogo.com/americangut

If that's not cool, I don't know what is.

*This post focuses on bacteria, since they are currently the main type of microbe under investigation in studies related to the human microbiome. I suspect that in time we will advance our scientific knowledge to equally understand the role of each of these microbes. It's going to be super-exciting, health and life-changing stuff. You can quote me on that.

Let Your Meat Take the Heat!

If you live in the U.S., chances are that you looked at the calendar this week and were surprised to realize that Thanksgiving is next Thursday. That's right folks, time to plan your menus because the government is giving us the day off to stuff our faces. Don't despair, I'm not about to tell you that your soon-to-be heaping plate of thanks is unhealthy. I'm a firm believer of everything in moderation (Alright, not everything. Heroin in moderation generally doesn't work out). In other words, just don't eat like it's Thanksgiving every day and you'll be fine.

What you should know, if you're an omnivore who plans to partake in gobbling up some turkey meat, is safe tips for preparing your holiday fowl. If all that meat is not thawed, cooked, and stored properly, the only thing you'll be thankful for is your toilet. You see, if you aren't careful, there are plenty of opportunities for your turkey to become overgrown with types of bacteria that cause food borne illness. To keep your Thanksgiving food-poisoning-free, here are some guidelines for safe turkey cooking:

• There are three thawing methods that have been deemed safe for turkeys: in the refrigerator, in cold water, or in the microwave. Detailed instructions on each method can be found here. 

• A meat thermometer is an essential Thanksgiving Day tool! Cook your turkey until it reaches a minimum internal temperature of 165 degrees Fahrenheit. Be sure to check the temperature where the turkey is thickest (breast and innermost portion of thigh and wing).

• Not all cooking methods are equal. Deep fried turducken anyone??? A variety of safe cooking methods can be found here.

• If you choose to stuff your turkey (yes, it's as dirty as it sounds), be sure to do so immediately before cooking. The stuffing should also reach a minimum temperature of 165 degrees Fahrenheit.

• As should be done whenever handling raw meat, be sure to wash all surfaces and utensils that come into contact with uncooked turkey as soon as possible. Please do not cut your sweet potatoes on a cutting board contaminated with raw turkey juices. That would be a tragedy on many levels.

• Leftovers, because that's bound to happen, should not be kept out at room temperature for longer than two hours. Before you take a nap, put the turkey in the refrigerator! Leftover turkey can be safely stored in the refrigerator for up to four days or in the freezer until it turns into a freezer burned icicle (about 6 months). 

Happy turkey day to all and remember to let your meat take the heat!

Don't Let the Flu Mess with You

The fall air brings much delight: jack-o-lanterns, apple pies, and piles of crunchy, multicolored leaves to jump in. It also brings some not-so-delightful things, like influenza. Every year, as you sip your first pumpkin latte of the season or buy your favorite pumpkin ale, you should think to yourself "now would be a great time to get a flu shot".

Despite historical evidence that influenza is nothing to mess around with, its power is often drastically minimized. The flu is not just a bad cold. Have you ever heard of someone being killed by a cold? I didn't think so. Influenza has the potential to be so deadly that it is responsible for one of the worst epidemics ever recorded: the 1918 flu , also called the "Spanish flu", which killed at least 20 million people. Though most flu strains aren't this dangerous, even seasonal flu causes thousands of deaths every year. And as 2009 reminded us, flu pandemics are not an event of the past. 

It's true that most people who get the flu won't die or suffer complications such as pneumonia, but they will be miserable, bed-ridden sacks of viruses. If you've had the flu, you know that it confines you to a horizontal position for about a week (sorry, no such thing as the "24-hour flu") while you alternate between fever-induced delusions and writhing in pain from body aches. It's not a good time. Not even worth some sick days. Trust me, the movies you've been wanting  to watch will not be funny if you have the flu.

If that's not reason enough to make you want to avoid the flu, consider what your infected respiratory droplets might do to those around you. Oh, you're home alone watching movies and won't get anyone else sick? WRONG - that strategy won't work. When you become infected with the flu, you are contagious for one day before you begin having symptoms.

Your best bet for protecting yourself and those around you is to get vaccinated each fall. While the flu vaccine doesn't provide immunity for all flu variations, it does guard against the three strains which are expected to be most common during a given season. Because there are so many strains of flu virus, and the virus is constantly mutating, the vaccine changes every year. Researchers around the world monitor flu activity in order to determine how the vaccine should be formulated for each flu season (talk about a stressful job). It's important to note that the vaccine is made from killed viruses, in other words the viruses cannot make you sick! The part of the virus that your immune system needs in order to produce antibodies against the pathogen remains. However, it is impossible for the flu vaccine to cause the flu (unless the nurse who gave you the shot sneezed on you).

Flu season generally peaks in winter, so now is the time to get vaccinated. Be smart and don't let the flu mess with you!

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Babies come from gametes: The truth about the birds and bees

If "the talk" your parent(s) gave you about the birds and the bees was anything like mine, it probably went a little something like this...

Mom: "When a man and a woman love each other... blah, blah, blah."
Me: (rolls eyes) "I already know this stuff, mom. I read about it in the encyclopedia."
Mom: "Blah, blah, blah."
Me: (looks disgusted because mom is talking about genitals)
Mom: "Blah, blah, blah.. and that's how a baby is made. Do you have any questions?"
Me: "No."

My mom deserves a huge round of applause because she did a great job handling that painfully awkward conversation. Not to mention, she let me live even though I was a little smart ass who thought looking up the terms "intercourse" and "reproduction" in a book somehow made me an authority on the subject. She also said many important, intelligent things that were not "blah" but that's how my know-it-all, embarrassed, 11 year-old self interpreted the content. Sorry, mom.

I won't pretend to know how to explain the origins of babies to children, but since we are all adults here (or seriously advanced children... does your mom know you're reading this?) we can say it like it is: there are lots of ways that babies are made!

First off, all babies might be gooey balls of love, but not all of them come from love. Sometimes babies are products of lust or failed birth control or too much tequila. Whatever the reasons behind conception, the worth of the baby is no different.

Secondly, not all babies are made by a man and a woman. To be accurate, all human babies are made from a sperm and an egg. But how this happens and who is involved in the baby-making varies from zygote to zygote. Here are some baby-making methods that were probably missing from your birds and bees talk:

• Eggs without sperm: Two people with eggs in a relationship, whether they be two women or a woman and a transman or any other combination, still have lots of options for pregnancy. One or both of the partners may choose to attempt pregnancy using donor sperm (preferably they try at different times because one pregnant person per household is plenty). They may choose a donor from a sperm bank or use a donor that is known to them (a friend or relative that is willing to donate). Once the sperm supply is identified, the partner attempting pregnancy may be inseminated in a clinic that offers alternative insemination services or choose to inseminate at home. Another option, in the case of partnered women each with a functional uterus, is to use one partner's egg and have the other partner carry the baby. This would occur through in vitro fertilization: the eggs would be retrieved from one partner, fertilized by donor sperm in a petri dish, and then implanted into the uterus of the partner carrying the baby. Single women who want to get pregnant without a partner, may also opt to use the alternative insemination techniques previously described.

• Sperm without eggs: Making babies when neither partner has eggs or a uterus is a little trickier but science can help with this too. One of the partner's sperm can be used to impregnate a surrogate. The surrogate can be known or someone who is found through a surrogacy agency. Depending on the arrangement, the surrogate may be directly inseminated with the sperm (using her own egg) or, as is typically the case, eggs will be obtained through an egg donor. In the case of a donor, the eggs will be fertilized with sperm via in vitro fertilization and then implanted into the surrogate's uterus. This is more common as the surrogate then has no genetic relationship to the baby she carries, avoiding messy legal repercussions. 

Alternative insemination techniques or in vitro fertilization may also be used when a man and women have difficult conceiving "the old-fashioned way".

Additionally, making a baby doesn't have to involve your own gametes (reproductive cells). No, I'm not referring to storks. I'm talking about adoption, an option for many families who can't conceive on their own or just opt not to.

So, now you know the truth: babies come from gametes. The rest is variable. And you're welcome. Your answer to "where do babies come from?" just became a lot less awkward. 

Lady Mosquitoes: Free Rides for Pathogens

Itchy welts left behind by mosquitoes are one thing, but the microscopic friends they can leave behind are another thing all together

Mosquito-borne diseases have been making national headlines recently through record-breaking numbers of West Nile virus and emerging cases of Eastern equine encephalitis. Though these are certainly newsworthy trends, there is nothing new about how good mosquitoes are at transmitting infectious diseases. It should come as no surprise given all the extra time they've had to evolve.While mosquitoes have been flying around Earth for approximately 220 million years , modern humans emerged only 200,000 years ago. This means that to mosquitoes, we really are nothing but fresh meat. At least to lady mosquitoes.

Female mosquitoes are the only ones interested in feeding on us as they need protein from our blood to develop their eggs. They track us down by scent, visual clues, and heat detection - all so they can use us as a blood meal for the purpose of laying up to 300 eggs. Unlike vampires, mosquitoes don't actually bite. Why are they called mosquito bites? Good question. Instead of biting, they actually pierce our skin with a mouth part called a proboscis. This is basically a needle-like structure that is used to suck our blood.

Since lady mosquitoes are essentially sticking us with used needles* every time they feed on us, it's no wonder they have an affinity for being disease vectors. With all the blood they drink, mosquitoes often slurp up blood-borne pathogens (viruses, bacteria, and parasites that cause illness). These pathogens then get a free ride to a new host without causing any harm to the mosquito, thanks to her anciently refined immune system. Transmission occurs through the mosquito's saliva, which is injected prior to feeding (it contains anticoagulants which are substances that prevent your blood from clotting). In addition to the aforementioned West Nile virus and Eastern equine encephalitis, mosquitoes can also infect humans with several other diseases including:

• Malaria
• Dengue fever
• Western equine encephalitis 
• Japanese encephalitis
• St. Louis encephalitis
• La Crosse encephalitis
• Yellow fever
• Rift Valley fever

The upshot? Not all pathogens survive after they've been ingested by a mosquito and therefore cannot be transmitted to a new host. Thankfully, this is the case for HIV. In case you didn't catch that the first time: mosquitoes do not transmit HIV!

Mosquitoes may have millions of years of evolution in their favor, but our big brains have found some ways to make ourselves seem less tasty to wannabe mama mosquitoes. Here are some ways you can prevent yourself from being used as a blood meal when participating in outdoor activities during mosquito season:

• Use an insect repellent containing DEET, picaridin, oil of lemon eucalyptus (also called PMD), or IR3535.
• Minimize skin exposure and wear light-colored clothing when in mosquito infested areas (e.g. wooded areas or areas with large bodies of standing water).
• Minimize areas of standing water around your home.
• Don't keep windows and doors open unless you have intact screens. 

Another safety measure you can take is to follow recommendations for prophylactic medications and vaccines when traveling to countries with high rates of mosquito-borne diseases.

When I was a teenager I thought smelling like bug spray was worse than putting up with itchy mosquito bites. I would like to officially retract that opinion.

*While the proboscis of a mosquito resembles a needle, a feeding mosquito does not employee the same mechanisms of a hypodermic syringe. Used syringes (also called needles) pose a different set of threats and should not be confused with insects.

OMG Everyone Has Genital HPV

Ok, so not everyone has genital HPV but unless you've taken a vow of life-long celibacy (which you intend to take seriously) chances are you've already had a genital HPV infection, you have one now, or you'll get one in the future. Before you freak out and run to your nearest STD clinic for treatment, take a deep breath and read this post in its entirety.

HPV stands for human papillomavirus, an extremely common virus that infects skin cells, including cells that line body cavities such as the vagina, anus, and mouth. Of the 100+ types of HPV that have been identified, about 40 are able to infect the genital region. While HPV is the most common sexually transmitted infection, affecting at least 50% of sexually active individuals, it has many characteristics that make it complicated, confusing, and unlike other STIs.

To begin with, the outcomes of genital HPV infection are highly variable. Most people with HPV are asymptomatic, will never know they are infected, and will eventually rid themselves of the virus through the defenses of their own immune system. Those are the lucky folks. Some types of HPV result in the development of genital warts while other types cause cellular changes that over time can lead to the development of cancer. In fact, HPV is responsible for nearly all cases of cervical cancer. Speaking of cervical cancer, if you haven't read The Immortal Life of Henrietta Lacks, please stop reading this and proceed to your nearest bookstore immediately. It's that good.

How people become infected with HPV is rather clear: skin-to-skin contact including contact with mucous membranes. That means anyone who is rubbing their naked body on anyone else's naked body is at risk for genital HPV infection. It doesn't matter what your sexual orientation is or what type of specific sex acts you partake in (sorry kids, dry humping won't keep you HPV-free). Barrier devices such as condoms and dental dams can decrease the risk of HPV transmission but the virus can still be spread to or from areas that the device doesn't cover.

What remains rather murky regarding HPV transmission is when exactly people are contagious and how long people can be infected before displaying evidence of the virus. Also, it is completely possible to be infected with more than one type of HPV. These factors make it nearly impossible to tell how long a person has been infected, who they were infected by, and whether they are at risk for infecting their current or future partners.

Even if you are one of the aforementioned lucky folks, it does not mean that the person you share your HPV with will be so lucky. Different strokes for different folks in the world of HPV. Fortunately, prevention against four of the particularly nasty HPV types is now available in the form of a vaccine. The HPV vaccine Gardasil provides protection against HPV types 6, 11, 16, and 18 and is approved for use in females and males ages 9-26. HPV types 6 and 11 cause approximately 90% of genital wart cases, while HPV 16 and 18 are responsible for most cases of HPV-related cancers. Vaccinating against HPV provides a dramatic reduction in risk, for both yourself and your lover(s). And yes, preteens should be vaccinated before they are sexually active in order to save them the agony of genital warts or an HPV-related cancer. Will vaccinating against a STI cause children to run out and have sex (yes, this is actually a debate to some people)? You tell me - does vaccinating against chickenpox cause kids to run around looking for playmates covered in chickenpox since they are now protected from their oozing pox blisters?

For those of us who have aged beyond 26 or who may have acquired one or more types of HPV prior to vaccination, don't despair! There have been many advances in science and medicine that have allowed HPV-related cancers to become increasingly preventable. Just because you have one of the high-risk (cancer-causing) strains of HPV does not mean you have, or will get, cancer. If you follow your doctor's recommendations for routine health screenings, such as for Pap smears*, the early cellular changes that MIGHT eventually result in cancer, can be monitored and treated before any cancer develops.

HPV may be the most common sexually transmitted infection but there is plenty you can do to decrease its potential harm. Don't let HPV catch you with your pants down!


*While cervical Pap smears are routine for anyone with a cervix, anal Pap smears are not nearly as common. Anyone who frequently has anal sex, particularly MSM (men who have sex with men) who engage in anal receptive sex, should find a medical provider who is educated in LGBT health, or at least willing to become educated, and inquire about anal Paps for detection of HPV-related cellular changes. Paps are not fun but anal cancer is far worse.