Fitness Rocks

Boosting Your Immunity to Reduce Your Risk of the Common Cold

In this episode of Fitness Rocks we look at ways you can strengthen your immune system that may help you avoid the common cold.

Healthy eating and regular exercise is an effective route.  The evidence for Echinacea and other dietary supplements is not convincing.

 

I apologize for the slow play of the podcast on the "PuPu Player"- I don't know why this occasionally happens.  It plays slow with the "listen now" button - but the good news is that it plays fine if you listen via iTunes.  I'm definitely not a sound engineer, so if anybody has an idea why this podcast doesn't play right on the "PuPu Player" please send me an e-mail.

 

References:

Nutritional Strategies to Counter Stress to the Immune System - ACSM Health and Fitness Journal

Exercise and the Incidence of the Common Cold

An Evaluation of Echinacea in Experimental Rhinovirus Infections - NEJM

Music:

Charlie Crowe - Crowe Jam

Jon Schmidt - All of Me

Spinach - It's Still a Good Thing

Spinach is loaded with nutrients that will keep you healthy.  We've all heard about the abundant vitamins and minerals in spinach - vitamin C, beta-carotene (a precursor to vitamin A), riboflavin, folate, vitamin B6, and magnesium.  But spinach is also filled with disease-preventing phytonutrients like lutein and zeaxanthin.  These phytonutrients are especially important in preventing macular degeneration, a leading cause of blindness (see my blog about diet and eye health).  The mix of phytonutrients in a diet filled with a variety of different kinds of fruits and vegetables are essential to good health and preventing a host of chronic diseases, including heart disease and some cancers.

Unfortunately, spinach lately has been loaded with E-coli bacteria resulting in several illnesses and even some deaths.  This has made a lot of people, including me, afraid to eat spinach. 

But there is good news in this month's issue of the University of California Berkeley Wellness Letter.  They report that there has never been a case of an E-coli outbreak coming from frozen spinach.  According to the article in the Wellness Letter, frozen vegetables are not only washed before freezing, but they are also "blanched" in boiling water which generally kills most bacteria.

Cooking spinach also helps to kill any remaining bugs.

There is a lot of enthusiasm these days for eating vegetables raw.  Here's an interesting fact - many of the nutrients in spinach, and other vegetables, are not absorbed well by our digestive tract unless the vegetable has been cooked (not overcooked).  The carotenoid phytonutrients in spinach are fat-soluble which means that they will be better absorbed by our body if they are cooked with a small amount of olive oil.

So that's the news for today - the Wellness Letter says frozen spinach is okay.

Monte Ladner, M.D.

Genetic Modification of Food Crops

In follow-up to yesterday's blog I have received two responses to e-mails I sent out to the scientists in the NPR report on declining nutrient levels in fruits and vegetables.  Today I will post the response (with permission) of Dr. John Juvik, a plant geneticist at the University of Illinois.  The text in black is my questions; the text in red is Dr. Juvik's answers.

1.  The differences in glucosinolate levels in broccoli you mentioned as being a consequence of genetics and environment.  Are these naturally occurring genetic differences, or the result of genetic modification?  Or both?

We have surveyed over 50 genotypes (varieties) of broccoli and observed substantial "natural" genetic variability in tocopherol (vitamin E), carotenoid (including vitamin A precursors), and glucosinolate form and content in the heads. Depending on the compound the concentrations ranged between the lowest and highest genotypes from 3 - 20 fold. Again, depending on the particular compound the proportion of the variation attributed to genetic differences among the varieties ranges from about 25-75%, with most of the remainder of variation due to the growing environment.  These differences are due to natural occurring variation that was fixed into these lines during the process of their selection in plant breeding programs to develop commercial varieties. 

There are currently no existing broccoli commercial genotypes that carry transgenes or are considered genetically engineered (GMO).  All have been developed through conventional sexual hybridization and selection by man. I am making the assumption when you use the term genetic modification you are referring to genetic engineering via plant transformation with a "transgene". Technically, conventional breeding is also genetic modification.     

2.  When a food crop is genetically engineered to be more resistant to insect infestation, I would assume this is done by boosting the plant's production of particular chemicals that are toxic to the insects.  What are the implications of this for humans who eat the plant?

Not necessarily, the current GMO example that is in broad commercial use involves corn, soybean, potato, cotton, etc. (but not broccoli or other fresh vegetables) varieties that have been transformed with the Bt endotoxin protein.  This protein is synthesized in extremely low concentrations in these transformed plant tissues and is not toxic to mammals at doses thousands of times greater. Development of crops by conventional breeding with resistance to insects has on some occasions been due to increasing the concentration of phytochemicals that are toxic to the insect. More often the mechanism of resistance is unknown or related to a change in the plant that renders it less attractive or palatable to insects. In the case of the glucosinolates and some other compounds enhancing concentrations will result first in increasing anticancer activity and health promotion, further increases will result in reduced advantageous bioactivity, and ever higher levels could lead to toxicity. Obviously any such modifications must be carefully evaluated prior to commercial release.  

3.  Most, if not all studies, looking at the health benefits of diets rich in fruits and vegetables have shown convincing evidence of improved health among people with primarily plant-based diets.  Conversely, there is essentially no good evidence that taking mega doses of single nutrients in the form of dietary supplements is good for us, and in some cases may be harmful.  The conclusions of many epidemiological researchers has been that it is the mixture and proportions of nutrients occurring naturally in plants that makes them good for us.  If we genetically engineer a plant to produce more of a particular phytonutrient - beyond its normal production and out of proportion with other nutrients in the plant won't we be creating a "supplement phenomenon" and very likely be doing more harm than good?

This is a question that has not been resolved.  Current information suggests that many dietary supplements are not very effective because they suffer from reduced uptake or poor targeting of bioactive components to necessary organs. This also results in a "burst" of  bioactive compounds in regions of the gut (stomach or small intestine) that may have limited effectiveness for uptake.  It is believed that health promoting phytochemicals that are presented and integrated in a masticated food matrix show improved uptake in more absorbent portions of the gut.  This form of presentation is also more gradual and can result in a greater dose of uptake due to longer duration of the compounds in more areas of the gut. Many of the compounds that researchers are working on in fruits and vegetables related to improving their health promotion are no where near levels that would cause any toxicity even with dramatic enhancement. 

It is my belief that it is not necessary to use genetic engineering to improve the health promoting properties in our fruits and vegetables. Existing variation can be utilized in conventional breeding programs.   

4.  The evidence for the benefits of a plant-based diet is clear and convincing.  I don't think the problem is in the random variation in nutrients among vegetables, I think it is that so few people eat a plant-based diet.  Wouldn't we be better off letting plants keep the genetic make-up they evolved with (the same genetic make-up we evolved to eat)?

Of course, this is the core of the problem, but what is a more achievable approach - dramatically changing the diet of the majority of humans or breeding a fruit or vegetable that is only eaten once a week or month to deliver more of the compounds that can reduce the incidence or cancer or heart disease?

5.  What are your concerns about the genetic modification of food crops regarding the implications for human health?

I think that any such modification, even through convention breeding, must be approached with great caution and careful evaluation for possible antagonistic outcomes.  

Are vegetables as nutritious today as they used to be?

National Public Radio did a report this past week that I am sure will become part of a new marketing campaign for the dietary supplement industry.  Researchers looking at archived USDA data from 1950 and 1999 regarding the levels of 13 nutrients in fruits and vegetables found that 6 of the 13 nutrients showed declining levels over time.

The claim that fruits and vegetables no longer contain adequate amounts of essential nutrients has already been in the marketing message of supplement manufacturers; I expect this will only add fuel to their fire.

Before you stop buying fruits and vegetables and start stocking up on supplements, let's try to look at the facts.  First of all, there are hundreds, if not thousands, of different phytochemicals in plants.  This study looked at thirteen nutrients and minerals.  We don't know about the others.  Secondly, there are several studies looking at the health of people consuming primarily plant-based diets during this time frame from 1950 to 1999, and beyond, and the overwhelming evidence is that these people are much healthier than people who don't eat fruits and vegetables. 

One genetics researcher mentioned in the report talked about the wide variation in broccoli content of plant compounds called glucosinolates - phytochemicals linked to a possible reduction in the risk of some cancers.  He pointed out that between individual broccoli plants there may be as much as a fifty-fold difference in glucosinolate content based on genetic differences between the two plants and the environments in which the two plants were grown.  As far as I can tell this is a naturally occurring difference and the obvious answer to this problem is to make sure you eat broccoli, and other plants, several times a week.

There is abundant evidence for the health benefits of diets high in fruits and vegetables.  There is scant, if any, evidence for the health benefits of taking supplements that provide mega doses of single nutrients, and in some cases (beta-carotene) mega doses of single nutrients may be harmful.

I have e-mailed three of the researchers involved in this report with questions about this issue.  If I get any responses I will report them here in this blog.

In the meantime, it is a very safe bet that eating apples and broccoli is still way better for you than eating cheese balls and candy bars.

Monte Ladner, M.D.  

Is Your Job Killing You?

Job stress has been linked to higher risks of developing high blood pressure and coronary heart disease. 

In this episode of Fitness Rocks we talk with Psychologist Dr. Mary Guarino about following individual passions to find a fulfilling career.

For most of us our job plays a big role in defining who we are as human beings - whether we like it or not.  Wouldn't it be great to have a job that excited you, a job that you actually loved doing and that gave meaning to your life? 

Dr. Mary Guarino owns Stellar Self in Washington, DC and is the author of It's Your Time Now: What Will You Do With It. 

Listen to what Dr. Guarino has to say about turning your passion into your life's work.

References:

Mary Guarino, Ph.D.

Job Strain and High Blood Pressure

Job Stress and the Risk of Coronary Heart Disease

Music:

Charlie Crowe - Crowe Jam

Jon Schmidt - All of Me

Effective Weight Loss Strategies

A listener wrote me recently about his struggle to lose a lot of weight.  He was proposing to follow a couple of the popular fad diets - I won't mention which ones in order to avoid the wrath of supporters of these diets.  For the record - I think all of the "lose-weight-quick" diets should be avoided in favor of developing sensible eating and exercise habits. 

For the inaugural Fitness Rocks blog I thought I would post my response to his e-mail question about how to proceed with the challenge of losing weight and regaining health.  Here it is: 

Dear Fitness Rocks listener (not his real name), 

Before I answer your question let me say that a really good book to get you going in the right direction is Eat, Drink, and be Healthy by Walter Willett, M.D. 

The two popular diets you mention have both been shown to result in weight loss at six months that is greater than other diets - but by one year the results of most popular diets are about the same - and pretty modest.  All fad diets have dismal long-term adherence rates. 

All of the discussion in the popular media about which fad diet is the best for quick weight loss completely misses the point.  The real answer is about developing a sustainable and healthy lifestyle. 

When I talk to people about weight loss I tell them the real goal should be developing healthy eating patterns and regular exercise, the weight loss will come as a secondary phenomenon.  That may sound like an irrelevant distinction, but let me tell you why it's not.  Being overweight or obese increases your risk for type 2 diabetes, high blood pressure, heart disease, prostate cancer, colon cancer, breast cancer, and other cancers, as well as osteoarthritis, and other unwanted chronic diseases.  Weight loss will bring those risks down - but the way you lose weight is important in how much you bring those risks down.   

For example, insulin resistance is common in overweight people and can lead to full blown type 2 diabetes.  Starting an exercise program will almost immediately reduce insulin resistance.  This reduction in insulin resistance will begin even before you lose a single pound purely as a consequence of the physiologic effects of exercise on your muscles. 

Changing your diet to a primarily plant-based diet with lots of fruits and vegetables (8 - 10 servings per day), along with whole grains, nuts, beans, only small amounts of lean meat, and nonfat or at least low-fat dairy products (if you eat dairy products) will begin to lower your blood pressure within two weeks - even if you haven't lost any weight at that point!  Losing weight will lower your blood pressure even more. 

This same plant-based diet (the so-called Mediterranean diet) will also give you a more favorable cholesterol panel, and is associated with lower premature death rates. 

Don't misunderstand me - your long-term health depends on you losing weight and maintaining that weight loss.  But if you work to change your food choices to healthier ones you will be creating habits that will improve your health and help you lose weight. 

Remember that there is more in food than just calories, fat, carbohydrates, and protein.  Fruits, vegetables, nuts, beans, and whole grains are loaded with hundreds, maybe thousands, of "phytonutrients," plant chemicals, that are essential to good health.  You can't get these in pills in the same way that nature gives them to us in whole foods - so don't waste your money on expensive supplements to make up for a bad diet! 

Typical American processed foods not only have the wrong kind of carbohydrates (highly refined white flour), and the wrong kind of fats (saturated and trans fat), but these processed foods are devoid of the health-promoting phytonutrients that whole grains, fruits and vegetables give us. 

Here's another example:  You're overweight and that is associated with an increased risk of prostate cancer.  While you are working to lose weight doesn't it also make sense to be eating whole foods that are known to decrease the risk of prostate cancer - like tomatoes? 

More good news about selecting plant-based foods as the mainstay of your diet is that they are relatively low in calories.  If you consider what a powerful nutritional punch they provide you're really getting the most bang for your buck with fruits and vegetables at a comparably low caloric cost.  Example: an average candy bar can have around 240 calories, and absolutely nothing in it that is good for you.  That is about the same number of calories that you would get by eating four medium sized apples!  And the apples are loaded with nutrients that promote your health.  Eat an apple, save 180 calories, and get healthier in the process. 

When a person gets around to deciding to take control of their weight what they really need to do is take control of their health, let the weight loss come as a side effect of healthy living.   

Work closely with your doctor who can monitor you for all of the obesity-related chronic diseases that we mentioned above.  You will benefit from having your doctor follow your blood pressure, blood sugar, cholesterol and other important markers for disease.  While you're going through the process of changing your lifestyle and losing weight your doctor may discover that your blood pressure is too high, you already have type 2 diabetes (an estimated six million Americans have type 2 diabetes and don't know it), or your cholesterol is too high.  In these cases your doctor may prescribe medication to control these - that is a good thing and not necessarily a permanent thing.  If you successfully change your lifestyle, and lose weight, you and your doctor may be able to eventually get you off the medication. 

Your doctor will also send you to a registered dietitian who will be very useful in helping you plan your meals and select healthy foods. 

Start exercising, but not until after your doctor has evaluated you for obesity-related diseases and "cleared you" to begin exercise.  Regular exercise is essential for good health and successful long-term weight control.  There is no substitute for regular exercise, you have to do it. 

Don't forget to do all the simple things you've heard about to increase physical activity throughout your day - walk instead of driving whenever you can.  Take the stairs.  Park at the far end of the parking lot when you're shopping.  Turn your breaks at work into mini-exercise sessions by pacing the halls of your office building instead of chowing down on cookies and watching the television in the office break room.  It's all obvious and simple - but people don't do it. 

Form a support group of friends and family who are interested in losing weight and getting healthy.  This is

America - you don't have to look any further than the person sitting next to you to find someone who should be taking better care of themselves. 

Shameless plug for Fitness Rocks - post your story in the Fitness Rocks forum and start building an online support group. 

Finally, don't get discouraged.  This is a long fight - a lifelong fight.  You can be successful if you design a lifelong plan at the beginning.  Weight loss and weight control are not things you do for three months; you do them every day for the rest of your life.  The better you become at doing these things, the longer, and healthier, the rest of your life will be. 

Have a great workout, 

Dr. Monte 

References:

Dietary Approach to Stop Hypertension - article from NEJM

Dietary Approach to Stop Hypertension with Sodium Restriction - article from NEJM

Mediterranean Diet, Lifestyle and Risk of Premature Death among Elderly European Men and Women

Dietary Supplements and Weight Loss - Not Likely to Help - American Journal of Clinical Nutrition

A Descriptive Study of Individuals Successful with Long-Term Weight Loss - American Journal of Clinical Nutrition

Liposuction Does Not Improve Obesity-Associated Metabolic Abnormalities

Weight Loss - It Can Add Years to Your Life

In this episode we review a recent medical article from the New England Journal of Medicine about the relationship between overweight, obesity, and the risk of premature death.  Being even moderately overweight carries an increased risk of premature death.

But don't despair; we are also going to review the basics of successful weight loss in an interview with a Fitness Rocks' listener.  Jason is going to share with us how he lost 44 pounds over six months and has maintained that weight loss for almost a year.  It turns out that achieving weight loss, and maintaining that weight loss, is not complicated, at least in Jason's case.

Listen to what Jason has to say about his own experience with successful weight loss - maybe his program of healthier eating and regular exercise will work for you!

References:

Overweight, Obesity, and Mortality in a Large Prospective Cohort of Persons 50 to 71 Years Old - NEJM

Body Mass Index Calculator

Jason's Post in the Fitness Rocks Forum

Music:

Charlie Crowe - Crowe Jam

Jon Schmidt - To the Summit

Harnessing the Power of Positive Thinking for Weight Loss and Development of Healthy Lifestyles

In this episode of Fitness Rocks we talk to Dr. Kirsten Harrell, a psychologist specializing in the field of Positive Psychology.  Dr. Harrell will review with us the basic principles of developing positive attitudes that can help you succeed in your weight loss program as well as developing and maintaining healthy lifestyle habits.

Can you harness the power of your thoughts to enhance weight loss?  Can positive attitudes help you stick with a plan of healthy eating and regular exercise?  Listen to the show and hear what Dr. Harrell has to say about attitudes, weight loss, and healthy lifestyles.

References:

Dr. Kirsten Harrell

Positive Psychology Progress - Article

The Science of Happiness - Article from Time Magazine

The Happiness Formula - A BBC News Program on Happiness Research

University of Pennsylvania Authentic Happiness Website

WebMD Article on Positive Psychology

Music:

Charlie Crowe - Crowe Jam

Jon Schmidt - Homecoming