Does Alcohol Keep Me Warm?

Yesterday I was listening to this rather entertaining story on NPR's "All Things Considered" involving variations on eggnog/holiday drinks: Don't Knock the Nog Until You've Tried this One.  I am definitely in the "eggnog is icky" camp (and I'm dairy allergic) but I like hearing tales of recipe improvement, so I was listening happily until the person being interviewed made the off the cuff remark about "some booze to keep you warm."  Some of you might be wondering if this is true, particularly if you remember the Bugs Bunny cartoons where St. Bernard dogs were used in avalanche "rescues" like this one:

Some of you might also get a warm, flushed feeling when you drink alcohol, as do I.  Unfortunately, whether it's brandy, rum, or even the gin in the martini (assuming cartoon St. Bernard dogs prefer gin), the booze will not serve to keep you warm while you're skiing, working outside, or chasing rabbits.  When you drink alcohol, even a swallow or two, the blood vessels under your skin artificially dilate and your warm blood moves closer to the skin, so you feel a temporary wave of warmth.  The problem, however, is that the warm blood moves away from your internal organs and causes your core temperature to drop.  If you were going to be outside in cold temperatures for a long period of time, you will be at an even higher risk of hypothermia.  Also, if you drink enough to impair your judgement, you might not come inside out of the cold when you need to, putting you at more risk.  So if you are planning on being outside for a long period of time, avoid the alcohol until you have the opportunity to be in a heated room.

While we are talking about myths, apparently the belief that St. Bernard's carried mini kegs of brandy around their necks while working as rescue dogs isn't true either.  The belief started after a 17 year old painter named Edwin Lanseer painted Alpine Mastiffs Reanimating a Distressed Traveler in 1820 after being impressed by the site of these personable dogs trained by monks for alpine rescue.    There is no other evidence that they actually carried brandy casks or that the monks actually thought it would be a good idea.

Take home message--Avoid alcohol if you are going to be working or playing out in the cold.

Supplement Specifics

This week is not starting of well for those who hope to make money from selling vitamin supplements, particularly multivitamins.  As summarized in this article three major studies published indicated that the use of a multivitamin did help ward off problems that strike fear into the hearts of many Americans: cancer, cognitive decline, and cardiovascular events.  

One of the highlights of this article was this quote: "I think this is a great example of how our intuition leads us astray," Salzberg told Shots. "It seems reasonable that if a little bit of something is good for you, them more should be better for you. It's not true. Supplementation with extra vitamins or micronutrients doesn't really benefit you if you don't have a deficiency." (emphasis mine).

When I pasted this article on my Facebook feed I people point out that they take [insert vitamin here] for [insert medical problem here].  Yes, of course you do.  You are taking a SPECIFIC vitamin at a SPECIFIC dose for a SPECIFIC problem.  That is different than throwing a random bunch of things and a problem that may or may not exist and not have any evidence that it's helping you.  "But I don't eat right" is another admission that I've heard from my patients over the years.  Well, you probably don't, but if you take a multivitamin to make up for your, lack of vegetables, you might still be getting too much of one thing and too little of another to really help.  And of course, as stated in the news article, some people take a multi w/o regard for how certain vitamins might actually increase the risk for certain conditions at high doses, might exacerbate a condition you already have, or might interact with a medication that you are taking.

I have actually covered a similar topic over a year ago in this post, which includes info on why taking a multi probably doesn't help your less than stellar diet, and also talked about who may or may not benefit from a vitamin D supplement.  Some of you are probably still wondering if you might need to have a supplement for a specific condition, so here are some questions to ask yourself.  And of course, get a blood test to verify that you are deficient and discuss your supplementation with a trusted physician and/or pharmacist so that you do not do yourself any harm.

1) Do I have a health condition that might keep my body from absorbing certain vitamins or minerals?  For example, if you have had gastric bypass surgery, you might need to supplement with B-12 as you may not produce enough of a substance call intrinsic factor to effectively absorb this from food.

2) Do I follow a diet that eliminates certain food groups/is considered restrictive by the culture I live in?  For example, if you are vegan, you won't get B-12 from plant sources because plants do not typically store B-12.  The "usual" plant sources, like seaweed, can actually contain substances that can keep you from absorbing B-12 (link), so you might be better off taking a supplement.

3) Do I take medications that can cause me to be deficient in certain vitamins/minerals? I have a lot of patients that are on diuretics ("water pills") for congestive heart failure, etc.  This medicine also can cause them to lose a lot of potassium in the urine, and so they need to take potassium supplements to compensate.  The supplements are usually pretty large doses, however, so they need regular lab work to make sure the potassium doesn't go to high (which could be fatal).

4) If I have a known deficiency, can I realistically eat the amount of food required to measure up to the amount in a supplement? For example, if you go to donate blood and find that your blood test was a tenth of a point off, you could probably just be extra conscious about your iron intake until your next attempt at giving blood.  If your iron levels are low enough that your physician is recommending a supplement, however, you might have to eat the equivalent of 2-2.5 pounds of liver per day to get the supplement equivalent.  I like liver, but not that much, nor would I want to pay for it.  I would take a supplement.

5) Do I have a condition that can be helped by large doses of a certain vitamin/mineral (that is backed by evidence)? See my previous post about supplementation with omega-3 in the presence of high triglycerides in HIV/AIDS patients treated with anti-retrovirals.  And remember, you will have to be monitored frequently to make sure that the potential side effects of those large doses are not outweighing the benefits.

Take home message--Find out if you really are deficient in something before taking a supplement that you don't need or could actually harm you.  If you do need to supplement, work closely with your physician to make sure you are getting the amount that you need of that specific vitamin/mineral.

Too (En)Riched for My Blood?

I just got a reminder e-mail for my regularly scheduled blood donation at one of our local blood donation centers.  I always appreciate the reminders mostly so I can make sure my smartphone/calendar reminders are set up, but also because the donation also changes my eating/drinking/exercise habits around that time.  I usually do not have a problem with the before donation tests that assesses my hemoglobin (the protein in my red blood cells that carries iron), but I know plenty of people that have shown up for their donation and were told that they did have a low hemoglobin.  So this was on my mind when this particular infographic showed up in my Facebook news feed:

And so the "is this true?" part begins.

First of all, I have a problem with the use of the word "anemia."  Anemia by itself means that there is a reduced number of red blood cells and/or hemoglobin in the blood; however, there are hundreds of different types of anemia and a variety of causes depending on what type you have (Which you can read more about here).  If you are "anemic" because of blood loss from falling and cutting yourself on a sharp object, for example, then you are going to need a transfusion and eating certain foods isn't going to help you.  Hopefully that type of example would be obvious, but I try not underestimate what people what people will and won't do, particularly if medical care is not readily available to them for whatever reason.  But for the sake of seeking out the original intent of this infographic, however, we will assume that this infographic speaks to anemia as a result of limited intake of iron.

Second of all, we also need to recognize the type of iron that your body absorbs the best from from food (aka the most bioavailable) is a type of iron called "heme iron" that is only found in animal protein sources (Link with links to other sources).  So if someone is looking to get what is truly best absorbed, vegetable sources or non-heme iron simply does not fit the bill.  The other related problems are that sometimes you are not going to eat enough of a certain food, like garlic, to be considered a good source of iron, and most plant tissue contains something called phytic acid which can prevent iron from being absorbed by the body (Phytic acid by itself is not bad, it's how plants store the mineral phosphorus and might actually play a role in keeping us from absorbing too much of certain minerals. Like anything else, it's the amount that matters).  So as a primary way of preventing anemia, I wouldn't put any of these on my top eight list.

"That's nice SkepticRD, but I refuse to eat animal products for [insert reason here] or I have trouble buying sources of heme iron for [insert reason here] and what I really want to do is see if there is something I can do to help me absorb non-heme iron better."
Fair enough.  First of all, go back to this link to find other, and sometimes better, sources of non-heme iron that are not listed here.  Second of all, when it comes to beans, nuts, and grains you can try soaking (48 hours or more), sprouting, and cooking to activate the enzymes in the plants that break down phytic acid.  Third, you can include more vegetables that have been fermented in your diet.  Fourth, you can make sure that you eat the non-heme iron foods with vitamin C rich fruit and vegetables.  Fifth, be aware of foods that you are eating that are rich in calcium as they can also prohibit absorption of iron rich foods.  Sixth, you can realize that there is a lot of work involved in doing all of the above steps, and you might want to have some compassion on those who choose to get their iron from heme sources.

Take home message---If you have anemia, discuss this with your physician to try to determine what type of anemia and potential causes.  If you need to improve your diet, go for the heme sources or be prepared to do a little more work for the non-heme ones.