Sunday, November 18, 2012

Does Alcohol Tolerance Mean Anything? -from John in Eden Prairie, MN

Here's John's full question on alcohol tolerance: 

1)   What is the physical mechanism by which drunkenness occurs, and how does a person’s alcohol tolerance play into that?

2)   If a person with a high alcohol tolerance consumed 6 beers, and another person of similar body composition with a low alcohol tolerance consumed 6 beers, would both people’s blood alcohol content be relatively similar?  i.e. Does a person’s tolerance affect alcohol absorption in the body or does it change the person’s reaction (drunkenness) to alcohol in the body?

John, thanks for the fun alcohol question!  Your questions are all about the pharmacology and metabolism of alcohol.  First, some important points about alcohol - it is a small molecule drug that is quickly absorbed in the gastrointestinal tract, and undergoes metabolism in the liver.  People have been consuming alcohol for ages.  Alcohol is one of the first anesthetics used for surgery before the discovery of modern anesthetics.  Surgeons would get people drunk enough to pass out or be disoriented for limb amputations or the like.  Alcohol also thins the blood - so those unfortunate patients were in danger of bleeding out during those surgeries.

 Alcohol has a complicated metabolic pathway, and is broken down by numerous different enzymes to several byproducts.  "Drunkeness" occurs via alcohol's effects on the the brain - alcohol binds the opiate receptors in neurons and impacts the release and re-release of dopamine.  Heroin, cocaine, and other addictive drugs also affect the opiate receptors.  That is a common feature between drugs of addiction.  That's where the "fun" part of alcohol comes into play - euphoric feelings, boisterousness, in other words, happy drunks because of altered dopamine release.  The physical effects of alcohol - dizziness, memory loss, vomiting, headache, sleepiness or lack of sleep, etc. are also partly due to alcohol's effects on the brain.  However, the byproducts of alcohol, such as acetaldehyde and lactic acid, contribute in a big way to alcohol's unpleasant effects.  Those are the two biggies that give you a hangover, make you feel sick.  Athletes get lactic acid build-up in muscles during tough, long work-outs - and sore muscles or "hitting the wall" can result from too much lactic acid.  A night of heavy drinking can cause lactic acid build-up throughout the body, causing all those unpleasant physical effects.  Alcohol metabolism also interferes with the natural breakdown of other wastes through competition with liver resources.   Hopefully that answered your first question.

Now - about differences between people who drink similar amounts of alcohol.  The two characteristics that have the biggest impact on drunkeness are body weight and amount of food consumed prior to drinking.  Bigger people have a larger volume with which to dilute the alcohol they consume, and a full stomach slows down alcohol absorption, allowing natural alcohol metabolism to "keep up" with the rate of drinking.  Everyone gets drunk faster on an empty stomach.  Individual variations come from genetic factors or subjective experiences.  Men tend to metabolize alcohol faster than women, so a man and a woman of the same body weight, eating the same meal, drinking the same drinks, will usually result in the woman being a bit more tipsy.  Aside from that, people have genetic variations in cytochrome P450 enzymes - some of the liver enzymes involved in alcohol breakdown.  Some CYP450 variants are "fast" variants or "slow" variants.  Some people with fast CYP450 variants have to be dosed with higher amounts of prescription meds for serious illnesses.  Also, other over-the-counter drugs and even foods can stimulate CYP450 production, making your liver more or less "prepared" to metabolize alcohol.   

Alcohol flush syndrome" or more commonly "the Asian flush" is due to a mutation in acetaldehyde dehydrogenase - causing accumulation of acetaldehyde in the body.  This causes flushing of the face, neck, and other areas, and more sick feelings from alcohol consumption due to acetaldehyde build-up.  People with seemingly "high tolerance" to alcohol might be fast metabolizers, or they may have so much practice drinking that they handle the effects better.  Some people have a subjectively lower threshold for "feeling drunk" compared to others.  Other people just don't react as obviously to alcohol - "quieter, more reserved" drunks, making them appear less drunk.  Alcoholics get very adept at appearing sober when actually drunk.  They can function almost normally with a high blood alcohol content.  

Lastly, if two people of the same body weight, same body composition, same age, and same CYP450 variants ate a standardized meal (clinical speak for controlled intake) and consumed the same amount of alcohol at exactly the same time, they should achieve the same peak blood alcohol content. In reality, there are so many variables that this would be hard to compare.  And still, those two people might appear drunk differently.  

Hope this helps, John, when trying to drink others under the table.     

 

Sunday, May 13, 2012

How can we prevent altitude sickness? -Tim in Dubuque, IA

Question:  My wife and I traveled to the Rocky Mountains, and she experienced extreme altitude sickness and didn't feel well at all.  We spent the day in Denver first, and she drinks gallons of water.  We bought this product, ChlorOxygen, from a health food store.  Will that help?  Anything else we can do? 

Thanks Tim, for the question!  What you described sounds like Acute Mountain Sickness, and can include nausea, headache, dizziness, fatigue, insomnia, and a general feeling of being unwell.  These symptoms are caused by a lack of oxygen in the blood from the lower atmospheric pressure.  Altitude sickness is tricky, and each person responds differently to changes in altitude.  It can happen to anyone - fit people, young, old, overweight, it doesn't matter.  However, fit people who exercise more often tend to experience less severe symptoms, and adjust faster.  There are exceptions though - altitude sickness can strike fit people too, sometimes very suddenly.

So what can you do?  Sounds like you are already taking some good steps by stopping first in Denver to acclimate, and drinking lots of water.  Here's a longer list of things you can do to prevent or reduce altitude sickness symptoms:

1.  Ascend slowly.  Spend a day in Denver, a day in Frisco or Dillon, and then go higher. 
2.  Drink plenty of fluids, avoid caffeine and alcohol which can dehydrate you or cause their own version of headaches.
3.  Take it easy the first few days.  Go shopping or visit tourist sites before skiing or climbing  a mountain.
4.  Exercise regularly to keep your red blood cell count up.  While it's not a sure thing, being a regular exerciser can increase your oxygen carrying capacity and reduce altitude sickness symptoms.
5.  Make sure you're not low in iron.  Iron is essential for hemoglobin, the protein in red blood cells that binds oxygen, to work correctly.  If your wife has low iron, this could be part of her troubles. She should get checked for chronic anemia.
5.  If you have recurrent, severe symptoms, consider asking your doctor for a prescription drug called Diamox  (Acetazolamide).  This drug causes the blood to become slightly more acidic and your respiration rate to increase, increasing oxygenation of the blood.  It can have upleasant side effects though, so use this only if you really need to.  I have friends who tried this drug and they experienced numbness of the feet, hands, and lips.  Not everyone has side effects though.
6.  Act like a tourist and try one of the oxygen bars.  Estes Park, Breckenridge, Vail, Aspen, and other touristy towns often have several oxygen bars where you can hang out and oxygenate your blood with fellow altitude sickness sufferers.  This is not a long-term solution though!

I checked out your herbal supplment, ChorOxygen. The active ingredient is chlorophyll, the pigment which gives plants their green color and enables them to produce oxygen from carbon dioxide. Unfortunately, you are not a plant.  Chlorophyll is not going to work the same in a human as it does in the leaves and needles of plants.  We don't have the right biochemistry or physiology to make chorophyll work for us.  If we did, we could just eat lettuce and dandelion leaves (yes, just eat the plants - those contain lots of chorophyll) and go sit outside in the sun and stop breathing.  Sorry, I doubt that herbal supplement does anything better than a big green salad.

Hope this helps.  Happy travels.

 


Wednesday, December 14, 2011

Iodine deficiency and testing for iodine deficiency

Andi, from Dubuque, Iowa, has sent in a very thoughtful question on the reasons, causes, and cures for iodine deficiency.  I will attempt to address each point:
Iodine deficiency can eventually result in thyroid problems, as the thyroid requires iodine to self-regulate and stay healthy. 
Yes, people on healthy (lower sodium) diets could eventually achieve iodine deficiency, because iodized salt is a main source of iodine in our diets.  People on low-salt diets (such as for blood pressure) can get plenty of iodine by using iodized sea salt sparingly.  It really doesn't take much! 

As for the similarities between chlorine, fluoridne, and iodine, check out the Periodic Table of the Elements here:  http://www.ptable.com/    You'll notice that these three elements are in the same column, column 17.  That means they all have the same number of electrons in their outer shell (7) which determines the chemical reactivity of the element.  Chlorine, bromine, and iodine have some similarities in terms of reactivity.  However, the body is generally very good at distinguishing between chemical species.  Chlorine in drinking water, at low levels, might displace some iodine in the body, but without more details from the "lock" and "key" analogy your nutritionist described (he is probably referring to an enzyme, or a cell-membrane transporter/channel for iodine) I cannot be certain. I need more information on that question.

For good thyroid health, use moderate amounts of iodized sea salt.  The hormonal changes due to peri-menopause and menopause can also cause thyroid problems, and many women in middle age experience hypo- or hyper-active thyroid disorder.  Also, general fatigue can be caused by hyponutremia (low sodium levels) if you drink a lot of water and avoid salt in foods. 
Hope this helps!        

On geology, oil, and mountains

Another geology question from David:  "Obviously oil and gas "pools" are quite deep under the surface of the earth.  Science tells us that the tectonic plates and their forces cause wrinkles or mountains.  These wrinkles go up.  What is the process for oil or decayed fossils to go down and then covered over with layers of rock?  The same forces apparently with the addition of sea bottom sediment and then a rise again?  There must be some intermediate process that causes the pool to stay together or are pools formed because the oil is trapped?"
Dear David,
Tectonic plates pushing mountains up is one kind of geologic process, and occurs due to the movement of the continental plates on the earth's crust.  Oil and natural gas formation is a different process, and generally much closer to the surface.  Oil, coal, and natural gas form when decaying plant or animal material gets covered and trapped by sedimentation, and eventually gets buried deeply by more sedimentation, or processes like landslides and volanic eruptions.  For oil and gas formation, trapping the material and providing pressure is key.  If left exposed, the material will decay into the soil instead of forming fossil fuels.  Fossil fuels are continuously forming right now, but at a much, much slower rate than we are using them.  The geologic processes that move continental plates (millions of years) are much slower then for fossil fuel formation (thousands of years) - the vast time scale of geology is something that we humans find very hard to grasp. 
Thanks for your question!

Monday, August 8, 2011

Does the hCG diet work? Is it safe?

Have you heard the ads on the radio?  Or seen all the internet ads for the hCG diet?  Have you tried it, or wondered if it's safe? 
Well DON'T TRY IT.  The SL cannot be emphatic enough on this one folks, the hCG diet is useless and dangerous.  hCG stands for human chorionic gonadotropin.  It is a hormone made by the embryo and the placenta during pregnancy.  It is excreted in urine during pregnancy, and detection of hCG is a common type of pregnancy test.  Diet ads will tell you eating or injecting hCG will aid weight loss - but it's bunk.  See also this article on Web\MD:  http://www.webmd.com/diet/features/truth-about-hcg-for-weight-loss
Any weight lost during the hCG diet is due to extreme calorie deficiency! 

Not only that, it's very dangerous.  The hCG being sold on the internet and other outlets is a biological therapeutic that is completely unregulated by the FDA.  There is no guarantee of the safety, purity, concentration, or even identity of the hCG you can buy.  Injecting an impure, questionably produced hormone into your own body can have serious side effects.  In fact, you could eventually have an immune reaction to hCG, a reaction that could make carrying a pregnancy impossible, as hCG is a critical hormone for successful pregnancy.  The real therapeutic hCG products are actually used to treat infertility, but those have been tested and approved by the FDA, which oversees the quality of the therapeutic product. 

Bottom line:  Do not try the hCG diet!  Most of the nutrition tips and diets I discussed on this blog are harmless, but this one is especially bad.  As always, magical secret cures are usually false. 

Friday, June 24, 2011

Is hydraulic fracking dangerous for ground water? - from David in Dubuque, Iowa

Here is David's full question:
"As I understand it, hydraulic "fracking" to extract natural gas is a process of drilling a mile or so deep and pumping in a special toxic fluid and shattering rock thereby releasing natural gas.  My question is, Is it reasonable to assume that the drill passes through an aquifer and if so, the casing will someday corrode or somehow the toxic fluid will find its way upward to the aquifer eventually.  Might we be making whole aquifers unfit for any use?  Naturally the gas companies say it's safe despite the famous flaming tap water video.  I hope you know some geology."

Great question!  Unfortunately the SL is not a super geology expert. However, the SL has a friend who happens to be a geophysicist. What luck! 
Here is the expert friend's opinion:
"It is unknown what the public health risks of hydraulic fracking used in natural gas extraction are. To the best of my knowledge, there hasn't been a scientific study with definitive results. The EPA is doing a study that should be out in a few years.

High concentrations of the hydraulic fracking fluid used in natural gas extraction is something I would definitely stay away from. To some extent, it gets diluted once it is pumped into the ground (usually several thousand feet deep). There is no definitive study that shows if/how this fluid gets into drinking water.

The fracking fluid is pumped in early in the well's life cycle. Once the cracks are made, sand or some other porous solid is put in place to keep the cracks open.  By the time a well casing starts to corrode, the fracking fluid stage will have been longer past. It is very possible that the well casing may crack or blow out though."

So hydraulic fracking sounds risky, and dangerous for drinking water! We cannot "assume" that any drilling will go through an aquifer though. Aquifers are not everywhere. We hope that drilling companies do some geological surveys first, and drill around the ground water. I would think a major aquifer would really screw up a drilling operation.  This is a great example of why we REALLY need the EPA, and why Congress' budget proposal to de-fund and strip the EPA of authority is a BAD idea. Big companies do not have our health as high on the priority list. Write your congressman! 

Better to be safe than sorry.  I recommend filtering your drinking water (not bottled water!). See my other blog post about clean drinking water here:  http://asksciencelady.blogspot.com/2010/12/what-is-best-way-to-ensure-clean.html

I cannot comment specifically on the video with flaming tap water.  You'd have to sent me the specific link.  Spills and leaks due to fracking are widespread, though, and the regulations are weak at best.  Right now it is up to the states to regulate fracking, and most of them are behind Big Oil in scrambling to keep up with what industry is doing. 

Wednesday, June 1, 2011

Sorry for the absence!

Dear Readers,
The Science Lady is sorry she hasn't been posting new questions over the last few months. She just started a new job and has been crazy busy!  The SL is ready to accept your questions again... so bring them on! 

Sincerely,
The Science Lady

Wednesday, February 23, 2011

What should I look for in a protein/snack bar? -from Tim in Dubuque, Iowa

Here's the question:  What’s the skinny on power bars?  I’m headed skiing in Colorado and want to eat something at lunch with my PB sandwich that helps me get through the afternoon. I’m confused by calories, sodium, sugar.  I want to eat something healthy.  What are some good guide lines for power bars?

Thanks for your question, Tim! You have a great question for athletes on the go. It's tough to carry something easy, healthy, and filling for a day of skiing, hiking, or other activity. Protein/snack bars are convenient, a great way to go. However, if you walk down that section in the grocery store, there are literally 100s of varieties. The key lies in the details on the nutrition label: you want maximum protein and not loads of sugar, and also some complex carbs. Athletes need protein and carbs to fuel the body. Sugar provides some quick energy for those afternoon energy slumps. For athletes, some sodium is fine, since you're going to drink lots of water and sweat a lot. The other thing to look at is the ingredients list. You don't want anything hydrogenated (trans fats), fake colors, preservatives, or a bunch of fake junk if you can avoid it. The actual Power Bar brand is not very good because they are highly processed. Also, the Myoplex, Atkins, and muscle-milk brands are very fake and processed. They contain lots of processed sugars and sugar alcohols.
The Clif bar brand is pretty good. It contains mostly all-natural ingredients and good amount of protein.  The Lara bar brand is very natural, only 5 ingredients, and is sweetened with dates instead of sugar. However, every flavor tastes a little bit like dates, so don't buy those if you don't like dates! Odwalla bars are quite tasty and all-natural, but a little light on the protein. For an athlete, you really want something with at least 9 or 10 grams of protein in a bar. Supplement a low protein bar with a piece of string cheese, or something else high-protein. For best results, buy a couple different kinds and see what you like best.
Another option is making your own protein bars! It's more work, but you can customize it. One of my favorite recipes combines Kashi Go-Lean cereal (very, very high protein and fiber) with peanut butter or almond butter, honey, and mix-ins like chocolate chunks or dried fruit. Dried cranberries and cherries work really well. Happy skiing!    

Sunday, February 6, 2011

Do people really need to sleep? Why?

Since the Science Lady hasn't gotten any new QUESTIONS lately, she's doing a several part series on Sleep. First off - do people really need to sleep? YES we do. Our furry companion cats and dogs sleep, as do all mammals and birds. Insects and fish don't really "sleep" like we do per se, but they sort of "zone out" and take mental rests. It seems that more social animals with larger brains require sleep. Why do we and other animals sleep? Several reasons: first, sleep provides a physical rest. It conserves energy. Our ancestors had limited food sources and had to conserve energy whenever possible, and sleep does that for us. Second, sleep gives the body opportunity to heal. Our sore muscles regenerate, the immune system fights infections, our skin cells renew themselves, etc. It gives the body a chance to "catch up" with everything we've done to it. Third, our brain is busy while we're sleeping. For adults, about 20-25% of our sleep is REM (random eye movement) sleep, and for infants, about 80% is REM sleep. REM sleep is when we have vivid dreams, and it's also thought to be critical for long-term memory formation. While we sleep, the brain sorts our memories and puts long-term memories into storage. Sleep deprived people have difficulty with short-term recall, attention, critical thinking skills, problem solving, and on and on. Sleep deprivation also elevates stress hormone levels, lowers our overall energy, causes mood problems, and overall makes us less efficient.

The current official record for sleep deprivation is held by Randy Gardner - a 17 year old who went for 11 days without sleep in 1964. Randy's case is still discussed in social psychology classes. Randy was supervised by a physician and a sleep researcher, William Dement. Randy was fairly high-functioning during the experiment, and they kept him awake using continuous games of pinball. However, Randy suffered from mood swings, loss of concentration, losing his temper, and had several hallucinations and delusions. On the fourth day he had a delusion that he was Paul Lowe winning the Rose Bowl, and that a street sign was a person. On the 11th day, when he was asked to subtract seven repeatedly, starting with 100, he stopped at 65. When asked why he had stopped, he replied that he had forgotten what he was doing. However, after 11 days of sleep deprivation, he could still speak coherently at a press conference. Randy slept for 14 1/2 hours afterward, then stayed awake for 24 hours, before resuming a normal sleep schedule. I wonder how this might have affected an older person, as a 17 year old might be able to bounce back better than most.

What about more normal sleep deprivation, such as when you get 4-6 hours of sleep per night repeatedly? You might not have hallucinations, but chronic sleep deprivation has been shown to increase moodiness,  increase stress hormones and "perceived levels of stress", drastically decrease mental performance and critical thinking skills, and also contribute to weight gain and risk of illness, including heart disease, viral infections, diabetes, etc. Next, the SL will tackle the common question: how much sleep is ideal? 

Friday, February 4, 2011

Is my mess making me fat? -insights on behavior, habits, and health

We've all heard it over and over again: eat healthy, exercise, yadda yadda to lose weight. We've also heard about the benefits of slowly changing our habits to accommodate a healthier lifestyle, such as working up to exercising more often, substituting unhealthy food for healthier food, etc. Habits are powerful things! Some interesting recent behavioral research suggests that overall lifestyle habits and personality types contribute to people being a healthy weight or overweight. For example, people who are better at waiting for "delayed gratification" are less likely to be overweight, less likely to be in debt, more likely to be financially stable, and tend to have cleaner, more organized houses. Evidently, balancing the checking account, taking care of our homes, and taking care of our bodies go hand in hand! It is unlikely that having a clean house causes a person to be healthy, rather, these habits are the result of persistence and discipline.  There is an abundance of reading on this topic, notably the book "Does this clutter make my butt look fat?" by Peter Walsh, and others.  Looking at this the other way around, people who go for instant gratification (like splurging on a new purse, or electronic gadget, or eating a giant cupcake) without considering the long-term consequences pay dearly with their credit score and their waistline. More disciplined folks are better at using household budgets, managing time, planning healthy menus, squeezing in exercise, and adhering to dietary restrictions.

So what is a procrastinating, disorganized, indebted person to do? Start somewhere! Habits can be changed, but it takes a lot of discipline to do so (which that person, by nature, doesn't have!). You can trick yourself into changing your habits, or enlist external forces to MAKE you do it. One resource is Stickk.com http://www.stickk.com/, which enables a person to make a commitment to do something (run a 5K, clean out the garage, pay of debt) within a certain timeframe or quite literally pay the price for not doing it. Announce lifestyle changes to supportive family members or close friends to make you accountable and add peer pressure to follow-through. Use positive reinforcement (i.e. rewards) for sticking to your goals. Notice and celebrate your progress! Take a "before" photo of yourself and the messy closet/garage, and compare as you go. And remember, not all things are changeable. Use your strengths to prop up your weaknesses. Example: The SL will NEVER be a Morning Person. It just ain't gonna happen. Despite all the "expert" advice about exercising first thing in the morning (those experts are definitely Morning People), the SL will continue to exercise in the evening, thankyouverymuch.