Archive for October, 2011

Getting it off versus keeping it off

Saturday, October 29th, 2011

What should you do when your scale calls for help?

I saw an interesting New York Times article on the 26th and kept it on my Kindle. It mentioned an article which just was published in The New England Journal of Medicine on why people who succeed in losing weight often find it difficult to not regain the pounds they've lost. Prior studies have speculated that a dieter's metabolism changes with altered hormone levels bringing about increases in appetite.

I just looked at the short form of the NEJM article online; I don't subscribe to that publication anymore and will have to get the whole article at the local hospital's medical library. It's a small but significant study, done by researchers in Melbourne, Australia utilizing fifty overweight or obese patients on an extreme ten-week diet, measuring levels of a number of hormones involved in appetite both at the end of the diet period and one year later.

The goal was to have the subjects lose ten percent of their body weight. Then they were to go on a maintenance diet to keep the weight off. Only thirty-four finished the diet period with the goal weight loss, some quit the study and others lost less than 10%.

So it's really a very small group, thirty-four successful dieters, who were followed for an additional year. They started at an average of 209 pounds, ate only 500 to 550 calories a day for the initial ten-week study period and lost an average of 29 pounds (14%) of their initial weight. A year later the average patient had gained back half what they had lost and the hormone measurements, especially of leptin, ghrelin and peptide YY, all involved in appetite one way or the other, were still not totally back to normal.

Maybe that's the reason so many people gain weight back after dieting. This may not have  been a large-scale study, but it speaks volumes.

Eat a healthy diet, not a 500-calorie/day plunge

The Los Angles Times commended on the article and on dieting in general. They noted that four out of five initially successful dieters regain their weight, sometimes more than they lost by dieting. Of course most of them hadn't gone on such a stringent diet. It makes much more sense to me to lose weight gradually, a pound or so a week is a reasonable goal.

I did that back in early 2009, losing ~30 pounds, and this morning I was still 27 pounds down. I also decided to make exercise a must in my busy schedule and go to the gym six days a week on the average. I can burn ~550 calories on the recumbent bike before I do stretches and work on a few machines. I also walk our new dog twice a day for 20-30 minutes.

Many people say they can't find that much time in their day and yet they find time for TV or movies or their email.

I think it's time to change priorities; take some of the time you spend sitting and walk or exercise instead. Gradual weight loss combined with an increase in calories burned makes much more sense than going on 500-calorie diets. I'd like to see measurements of those same hormones in a group who try this approach.

Otherwise you're just paraphrasing Admiral David Farragut at the 1864 Battle of Mobile Bay, "Damn those hormone levels; full speed ahead."

 

 

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Posted in medically-oriented background info, Obesity, Publications, Weight Loss | No Comments »

Which study should I believe?

Wednesday, October 26th, 2011

Vitamin E has this chemical structure

I just read the recent (Oct 12, 2011) JAMA article on "Vitamin E and the Risk of Prostate Cancer." It was a long-term, prospective, randomized study of 33,533 men followed in 427 study sites in the US, Canada and Puerto Rico. The investigators were from major academic centers, Duke, the Cleveland Clinic, Brigham and Woman's Hospital (e.g., Harvard) and the National Cancer Institute among them.

This was an impressive study of the effects of Vitamin E and/or selenium versus placebo that began in 2001 with the subjects being "relatively healthy men." Seven years after it began, in September 2008, the independent data and safety monitoring committee decided that the supplements should be stopped as there had been no positive results (reduction in prostate cancer detection) and futility analysis (a statistical tool) said the results were quite likely to be negative (more cases of prostate cancer). I hadn't heard of that term and found a medical website that discussed a number of reasons for ending a study prior to the intended date. I'll paste in the URL if you want to read a one-pager on what is called "interim analysis."

http://www.childrensmercy.org/stats/plan/interim.aspx

In this study, though the researchers stopped giving supplements and published an article (JAMA.2009;301(1):39–51) on the results to date, which showed a higher (but not statistically significant) number of cases of  prostate cancer in the groups receiving Vitamin E, selenium or both, they also continued following the patient group.

Prostatic cancer under the microscope

The later data, though July 5, 2011, was quite impressive. There was a 17% higher incidence of prostate cancer in the group taking Vitamin E. In most scientific studies a p-value of 0.05  is felt to be significant. That translates to a probability of 5% or less that whatever happened did so by chance. If the data calculates to a p- value of 0.01, there's a 1% chance this was a random occurrence. Here, after ~eleven years the p-value for Vitamin E increasing the chance a man was diagnosed with prostate cancer was 0,008. (I'll paste in a website that explains more of this stuff if you're remotely interested).   http://www.childrensmercy.org/stats/definitions/pvalue.htm

Why all the math and statistics?

Well, for starters, a few years back a large study showed the exact opposite, but in a highly selected group: men in Finland who were smokers. Another study, done with physicians as the subjects, showed no effect on the incidence of prostate cancer. A post by a physician harshly criticized the SELECT trial as part of a lengthy defense of supplements, but made sweeping pronouncements without supplying data or references to specific articles.

I read the articles, the blog post and the new study in detail. I know that medical research projects often come to conclusions that, a few years later, are "proven" incorrect. But I think this study was carefully done, had a clear-cut purpose in mind and included a large enough group of subjects that I'm going to believe its conclusions.

Plus I'm certainly not a Finnish smoker.

 

 

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The Five-Second Rule revisited

Friday, October 21st, 2011

don't wind up here, or worse

When I was a kid, we often used the Five-Second Rule, that meant food falling on a relative clean surface could be eaten if it was picked up in less than that amount of time. In recent years I've heard jokes about this rule: when parents have their first child, they use five seconds as a safe time, with the second, it's ten seconds and with later children, it's wipe off the mud and let them eat whatever dropped.

I received the November issue of the Center for Science in the Public Interest's Nutrition Action Healthletter several days ago  and noticed this month's focus was "Safe at Home: How to keep your kitchen from making you sick." I haven't had time to read much of the issue, but leafed through it and saw a brief blurb titled "Ignore the five-second rule."

So today I re-read that section, then went online and found the original article in the Journal of Applied Microbiology and Googled the lead author. Dr. Paul Dawson is a Professor of Food Science at Clemson, got his PhD at North Carolina State University, then did a two-year post-doctoral fellowship. Since joining the Clemson faculty he's published over 80 research manuscripts.

He was on a CNN TV show in 2010 discussing the 5-second rule, double-dipping (chips into a cheese or salsa dip) and, most recently was working on a project on the bacteriologic safety of blowing out birthday candles (See link below).

I read the online 2006 version of the original article in the Journal of Applied Microbiology, which appeared in paper format in April of 2007. Some of the background data is of interest: over 75,000,000 cases of food-borne illness occur in the United States each year and 5,200 of these result in deaths. Dawson's experiments were performed using Salmonella bacteria, which is found in a substantial percentage of poultry, roughly 10% in two studies by the USDA.

Every surface is a danger zone

My take on Dawson's results is 1). bacteria excrete chemicals allowing them to adhere to nearly any kind of surface (e.g., tile, rugs, cutting boards); 2). once they do so they have "biofilms," microscopic layers that allow them to survive for extended periods of time; 3). they can transfer from those surfaces to a variety of foods (Dawson used bread and bologna) very rapidly; so 4). the five-second rule is invalid and we all need to work on more effectively cleaning "food contact surfaces (counter tops and cutting boards come to mind).

I enjoyed watching the CNN interview with Dr. Dawson and will be intrigued to find out what his birthday candle research will show. In the meantime, I'll quit picking up food that has fallen on what appear to be clean surfaces; they're not.

http://newsroom.blogs.cnn.com/2010/08/01/five-second-rule-urban-myth-or-scientific-fact/

 

 

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Posted in Food safety, Food-related disease, Healthy eating, medically-oriented background info | 2 Comments »

Do I need to eat my words?

Wednesday, October 19th, 2011

Different choices for different ages

An old friend forwarded an article on vitamins yesterday, one that I read with special interest. It came from MedPage Today, an online medical news service for healthcare professionals that partners with the University of Pennsylvania School of Medicine to offer physicians continuing medical education credit (CME) for reading articles and then answering a few questions.

The article was titled "Vitamin Studies Spell Confusion for Patients" and extensively quoted Dr. David Katz fromYale's prevention research center. He is an adjunct Associate Professor at Yale's School of Medicine and an internationally renowned authority on nutrition. He comments that, based on the recent study I mentioned several posts ago, many clinicians say they've written off supplements for good.

Yet 50% of Americans take supplements; many take more than just a multivitamin.

Then Dr. Katz offers some caveats as I did, stating the Iowa study is "merely observational and can't prove cause and effect." He still recommends omega-3 fatty acids (AKA "fish oil") and vitamin D for most of his patients and adds calcium for women and prenatal vitamins and folic acid for pregnant women. otherwise he only uses vitamins when there are deficiencies.

A recent pole of clinicians found that 70% favor annual screening of specific vitamin levels to treat deficiencies. Which vitamins (and minerals) might be measured as part of an annual focused screening examination and whether medical insurance plans would cover such laboratory tests has not been delineated, as best I can find.

But I'm seventy, and articles from 2005 to 2010 in authoritative sources, talk about seniors needing much more B12, having multiple minor, but significant, vitamin deficiencies, and not eating well-balanced, healthy diets, even here in the United States, much less in other spots around the world. I'm lactase deficient and small-boned; do I need a calcium supplement?

clearly the best way to get your vitamins

I agree with Dr. Katz that eating a balanced diet would be a better answer, at least for those who are younger. The concept of "eating your colors," i.e., having multiple suit and vegetable dishes over the day which contain different phytochemicals as represented by the color of the food itself, makes great sense.

How many Americans do that at present or are likely to do that even if medical figures recommend such?

I regard this as an ongoing discussion. Dr. Katz is certainly correct in saying that vitamins have been shown to treat disease states, but not to prevent chronic disease. The surmise in the article in MedPage seems sound to me: vitamin isolates are less effective on their own and a full blend of antioxidants and phytochemicals (again, best found in those whole fresh fruits and vegetables, may be the key to obtaining maximum benefits.

This discussion is likely to go on and on, so I'll supply two URLs that may help you, in consultation with your own physician, make choices that are relevant to your nutritional status, age and degree of health.

http://www.uspharmacist.com/content/d/senior%20care/c/21981/

http://www.fda.gov/Food/DietarySupplements/ConsumerInformation/ucm110493.htm

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Listeria

Friday, October 14th, 2011

The culprits, this time.

Reading "USA Today" online, I found an article detailing the repercussions of the recent/ongoing outbreak of disease linked to cantaloupes coming from one specific farm in Colorado. That operation, Jensen Farms, re-called its fruit in mid-September. The Food and Drug Administration and the Seattle-based Institute for Environmental Health have not yet found the root cause of the outbreak. Since the normal shelf life for cantaloupe is ~two weeks, none of the Jensen Farm product should still be in stores. And no other sources have been implicated. Nonetheless, cantaloupe producers in California and Arizona, the two states with the largest crops of this fruit, are seeing sales plummet 80% or more.

That probably shouldn't surprise us. Spinach sales, devastated by the 2006 E. coli outbreak, are still down nearly a third in one California county.

As of October 12, the current outbreak had led to 116 illnesses and 23 deaths, making it the deadliest in more than a quarter century. There was another outbreak in Texas in October of 2010; that one was related to celery and resulted in 10 total illnesses and five deaths.

I went to several online medical sites to refresh my memory on Listeriosis. When I dealt with infections from this bacteria it was in immuno-compromised patients. Listeria is found worldwide, often in association with farm animals, many of which are otherwise healthy carriers of the bacterium. People can also be carriers and perhaps five to ten percent of us have Listeria in our bowel flora.

There are roughly 2,500 US cases of Listeria infections yearly and about a fifth of those infected die. Most are isolated cases, not major outbreaks The bacteria isn't transferred from person to person with the exception of pregnant women and their fetuses or newborn babies.

This is a foodborne illness, most commonly associated with improperly processed deli meats or unpasteurized milk products.

About 30% of all reported US cases occur in pregnant women. As opposed to the majority of us, who may have nonspecific symptoms, or none at all, pregnant women can transmit the infection to their fetuses or to their newborn infants. They also may have minor symptoms, if they are otherwise healthy, but Listeria can lead to miscarriages, stillbirth, premature birth or, potentially, to serious disease or death of newborn babies.

Others at higher risk for serious disease when infected with this bacterium include the elderly, diabetics, cancer patient, AIDS patient, those with significant kidney disease and anyone on immunosuppressive drugs.

It's tough to diagnose Listeria infections: the most common signs and symptoms include fever, muscle aches, nausea and/or diarrhea. There are no reliable tests for the bacteria, so the diagnosis is difficult in the absence of a history of exposure to a potentially contaminated food source during an outbreak.

Most of us clear the infection without any treatment; those at higher risk should be considered for immediate IV antibiotics and consultation with an Infectious Disease specialist is recommended (and if a pregnant woman has the inception, an Ob-Gyn specialist and a Pediatrician should be involved.

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Posted in environmental issues, farm-worker issues, food and food-producing animals, Food producers and less-healthy foods, Food safety, Food-related disease, Governmental Efforts, medically-oriented background info, Publications | No Comments »

It's Yo-Yo time again

Wednesday, October 12th, 2011

take pills or eat right, is that the question?

 

 

 

 

A recent edition of The Wall Street Journal had an article titled "Supplements Offer Risks, Little Benefit, Study Says." It quoted a long-term study of Iowa women, uniform Caucasian and with a mean age of 61.6 in 1986 when the research began. This was not a prospective, randomized controlled trial (RCT), but a cohort study, i.e., a number of people grouped together for a particular reason.

When I Googled the original purpose of the research project I found the following statement:

The Iowa Women's Health Study (IWHS), started in 1986, is a cohort of 41,836 postmenopausal women aged 55-69 at baseline. The primary aims of the study were to:

1) Determine if the distribution of body fat (waist/hip) predicts incidence of chronic diseases, with the primary endpoints being total mortality, and incident cancers of the breast, endometrium, and ovaries, and

2) Determine to what degree diet and other lifestyle factors influence risk of chronic disease.

So who could resist this incredible pool of data?  I was intrigued to note the authors of this paper were from Finland, Minnesota, South Korea and Norway; three were PhDs and one had a Doctorate in Pharmacy + a Masters degree in Public Health. I somewhat doubt they were the originators of the IWHS.

I found other papers stemming from this study: one concluded that drinking lots of decaf coffee was associated with less type 2 Diabetes, another looked at rheumatoid arthritis, another at colon cancer incidence.

I renewed my long-expired membership in the American Medical Association this morning (it's very inexpensive for an older retired physician) in order to have access to the full article.These authors looked at vitamin and mineral supplement use in 38,772 of the women. I agree with their take on supplement use in general (it helps in those clearly deficient; the rest of us who take them do so in hope of preventing chronic diseases and lowering our risk of dying prematurely).

The data from numerous studies, in terms of mortality risk, has been inconclusive. There have only been a few RCTs (mostly looking at calcium supplementation and vitamin use) that have said it's good to take supplements. Others have said not only do they not help, they may harm.

I read the conflicting reports with a jaundiced eye, but this one has a lot of accumulated data and it's at least worth paying close attention to. The basic conclusions in this particular population set (white women in Iowa) were that calcium supplements are good, iron supplements are bad and the rest don't help.

There are a few, maybe more than a few caveats. This is an association, not a causation, although the authors tried to eliminate many of the possible differences between those who did and those who did not take supplements. The fact that this wasn't an RCT meant the two groups differed in a number of fundamental ways. This was not a study originally set up to test if supplements helped or hurt or neither.

Bottom line: the paper is impressive, but won't change my own use of supplements in any way

 

 

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Eating our way across Portugal

Thursday, October 6th, 2011

 

 

We started just west of Lisbon

 

 

We're on a three and a half week trip, almost all in Portugal. I wasn't planning to add any posts, but brought my iPad2 and realized I could find Wi-Fi connections in many places. So now we're on a two-day farm stay in the Duoro Valley, heart of the Port wine grape industry and we're eating well, perhaps too well.

I'm not normally a chocolate eater but the Mousse de Chocolata" here has been wonderful. I realized today that I've eaten more desserts and more bread (freshly made) than usual, but my slacks still fit and I' using the same belt notch.

So what's keeping me from gaining a significant amount of weight?

To begin with we're often eating one main meal, one smaller one and a fruit or yogurt snack. Breakfasts here have freshly squeezed orange juice, rolls that don't need butter and some cheese. Our lunches have often been eaten in transit and, more often than not, have been light.

Then too we're walking 45 minutes to two hours a day, often up and down hills.

Today for lunch we returned to the same wonderful gourmet restaurant we'd been to last night. As in the previous meal portions were smaller than we get at home. We ate slowly savoring each bite and drank a third of a glass of a late harvest wine the chef had sent us. My wife had a fruit and vegetable salad, while I ate a fish fillet. We really dawdled for an hour and forty minutes, talking, putting our forks down between smaller-than-usual bites and talking...a lot.

I realized we'd spent two and a half hours over dinner the previous evening. This was a European way of dining I noticed as I looked around. Nobody was in a hurry and, tellingly, nobody seemed significantly overweight.

So I've learned a lesson or two on this trip and, in doing so, have enjoyed my food more.

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Eating and drinking in Europe: part two

Wednesday, October 5th, 2011

I may switch to red wine

I've been reflecting about our wine drinking in Europe. Here I normally have one glass of sweet white wine (e.g., Riesling Spatlese) three times a week.  It's very rare that I'll have a second glass and when that occurs it's almost always at home. When we're at an evening event we routinely have a "designated drinker" and a designated driver. That's been our pattern for more than twenty years, ever since I saw an Army senior physician, about to move into a choice command position, make the irrevocable error of over-consumption of liquor at a party.

I've noticed a few months ago that other countries have considerably lower blood alcohol limits for drivers than ours in the United States: that altered my own behavior. Rarely in the past, if we were going to spend three or four hours at a party, I might have one drink at the start of the festivities and drive home some hours later. That no longer makes sense.

However, in Portugal, we almost always walked to restaurants and we almost always drank red wine: vino verde (I discovered this meant "young wine", not "green wine), Port or regional products. We were sitting next to a German couple at one delightful meal and started talking about our imbibing habits. They had a white wine bottle on their table while we were trying a local red . They said at home they usually have wine with dinner and drink a bottle every three days. On vacation, they were drinking a bottle a night.

We brought a half bottle back to the hotel and finished it the following evening sitting on the third-story terrace.

Normally, if I do have a second glass of wine I feel a slight buzz. That wasn't happening on this trip. When I thought about it I realized we weren't drinking standing up at a reception, but sitting down at a prolonged meal. Our typical dinner in the States lasts an hour; here we averaged two and a half hours. So both the length of time and our food intake played a part in moderating the effect of the alcohol we were consuming.

We're home now and back to our normal pattern. We ate at our favorite local restaurant yesterday and I had a Thai Ice tea and no wine.

I'm not suggesting any of you should start drinking wine if you don't now, and for those of you who do drink wine now I'm certainly not pushing for increased amounts (having seen far too many cases of cirrhosis). The medical data for a favorable effect of moderate red wine consumption is suggestive, but not definitive as I mentioned in my comments extracted from a Mayo Clinic website. At age seventy, with no history of overconsumption in my family, I'm choosing to err on the side of  the vino. I may even switch from white to red wine.

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Posted in beverages, Healthly lifestyle, Life extension, medically-oriented background info, scientific controversies | No Comments »