A serious complication of getting older is the loss of muscle mass and strength.  The weaker, smaller muscles that come with aging have serious consequences: lower quality of life, more falls and subsequent fractures (which lead to surgeries, long hospital stays, and nursing home admissions), and reduced independence.

One perspective missing in the understanding of aging muscle is what changes occur naturally in the muscle tissue of healthy, older adults (over 70); specifically, what happens to the quality of the muscle and how much fat gets deposited in the muscle tissue over time.

Led by researchers from Pitt, scientists followed nearly 1,700 men and women (white and non-white, all over age 70) for five years.  During that period, researchers measured changes in body weight and body composition (fat vs. fat-free mass), muscle strength (specifically of the thigh muscles), and muscle size.  The adults in this study had a high level of functioning, but were not physically active beyond doing daily chores and walking around.

The changes were dramatic: both men and women had more fat deposits in their muscle tissue at the end of five years, regardless of whether they gained or lost weight during the study period.  The fatty tissue likely contributed to both a decline in muscle function and a low level of persistent inflammation that is thought to foster many chronic ailments.  Men lost 16% of their leg strength, while women lost 13%. In fact, both men and women lost muscle strength much faster than they lost muscle size.  This means that the quality of their muscle tissue declined; this is possibly to do the loss of connectivity between the nervous system and individual muscles that occurs with age.

This was not an exercise study, so there was no intervention to understand how different fitness activities might stem these changes. However, previous research in older adults tells a compelling story about the benefits of both strength and aerobic work.  Older adults who strength train, for example, actually build both muscle mass and strength.  In addition, the loss of efficiency between the nervous system and individual muscles (known as ‘denervation’) can be blunted by exercise, especially activities that are sometimes vigorous or intense.  And, although, everyone declines eventually, a higher level of fitness gives you a better quality of life for as long as you are willing to work for it.

You will get only one chance to age well. A successful late middle-age and beyond largely derives from sound choices made with foresight and a clear-eyed recognition of the consequences of choosing badly.  Choose well: build an activity program that has both aerobic and strength components and that gradually expands and diversifies as you get older.

Source: Delmonico, MJ, et al.  Longitudinal study of muscle strength, quality, and adipose tissue infiltration.  Am. J. of Clinical Nutrition.  Dec. 2009. 90:6; 1579-1585.

Some things to consider as we prepare for the food hurricane known as Thanksgiving.

• Make physical activity your eating ally: the simple act of taking a long walk (an hour or more) on Thanksgiving morning will help you process the calories that you eat later in the day.  The activity has specific benefits:
• It reduces fat circulating your bloodstream by up to 16%; for people who are regularly active, this benefit may rise to as much as 30%;
• It helps improves the use of fat for energy for up to six hours after you eat; and,
• It improves insulin sensitivity and, thus, glucose metabolism.

Don’t despair, however, if you miss activity on Thanksgiving morning.  Taking a long walk AFTER eating can also help you by improving blood flow through arteries. 

The CAKE Study, published in 2007 showed, in a very simple and elegant way, the adverse impact of a single high-fat meal.  Meals high in saturated fats impede the ability of HDL (good cholesterol) to do its job, making artery walls were more susceptible to damage after a meal high in saturated fats compared a meal high in unsaturated fats. 

Enjoy Thanksgiving, but eat wisely and remain as active as possible.  Make positive choices and you can come through this holiday weekend with a strong sense of gratitude for your own positive decision making.      

Source: Nicholls, S, et al.  Consumption of saturated fats impairs the anti-inflammatory properties of high density lipoproteins and endothelial function.  J. of the American College of Cardiology.  August 15, 2007.  48:4; 715-720.

With flu season (both seasonal and H1N1) in full swing, one of the more common questions asked me of is whether exercise will help to ward off or prevent the worsening of common upper respiratory infections (URIs), such as the flu or the common cold.  This question about viral URIs is important because respiratory viral infections account for over 200,000 hospitalizations each year, and the flu alone produces 36,000 deaths (mostly among the very young and the very old).  Indeed, the Centers for Disease Control and Prevention (www.cdc.gov) estimate that 22 million Americans have gotten H1N1.  So the question of whether (and what kind) of physical activity might reduce this risk is critically important, because a personal-fitness-based strategy is cheap, achievable by nearly anyone, and good for you in many ways that go beyond infection prevention.

There is good evidence that regular, moderate exercise helps to promote healthy immune system, and that doing so improves your immune system’s response to the viruses that cause URIs.  The studies, however, were not perfect, because they often relied upon self-reported information about both exercise activity and the symptoms of the infection.  Nonetheless, they produced consistent results, showing that people who are sedentary have an increased risk of more URIs, and of having more severe symptoms when they get sick. 

Interestingly, hard exercise may actually tip people over the edge and make them more vulnerable to infection and to more severe infections, by shifting the immune system’s response in an unhelpful direction.  

Hence, it appears that the relationship between immune function and the risk of a URI, such as the flu or a cold, is J shaped.  People who are sedentary are at the far left end of the J…they do no regular activity, and, thus, have a less powerful immune response to infection.  As physical activity goes up so, too, does the immune system’s response (the vertical portion of the J).  This happens up to a point, when, it appears that prolonged, hard exercise, can start to depress immune response.  Studies in animals and controlled trials in people support this theory, showing that elite athletes get sick more often than recreational athletes. 

We are now deep into cold and flu season, and people are justifiably concerned about the impact of both the seasonal flu and the H1N1 flu on their health.  You could waste your money on any number of unproven supplements that claim to help ward or cure common viral illnesses (http://abcnews.go.com/Health/ColdFlu/story?id=4380374&page=1) , or you can do what is scientifically sound, sensible, and achievable: eat well, making sure that you minimize your intake of highly processed foods, and enjoy plenty of fruits, vegetables, and whole grains; exercise regularly at a moderate intensity (about 4 or 5 on scale of 0 to 11); minimize very hard workouts (7 or over on the same scale), and DO NOT work out if you are already sick; wash your hands regularly and avoid touching your eyes, nose, and mouth, all of which are entry points for URI viruses ; stay away from people who are obviously sick; get plenty of sleep; and, stay home if you are sick.  Oh, and, of course, get your vaccinations.  These strategies will all help, are evidence-based, and have virtually no incremental cost, except for the $20 or so to get a flu vaccine.

For good, reliable advice on the seasonal flu, visit http://www.cdc.gov/flu/; go to http://www.cdc.gov/h1n1flu/ for information specifically about H1N1.  

Source: Martin, SA, et al.  Exercise and respiratory tract viral infections.  Exercise and Sports Sciences Reviews.  October 2009.  37:4; 157-164.

The words “whole grain” now have increased importance as the nation deals with both the obesity crisis and the elevated risk of heart disease that comes with it.  It is important, however, to understand not all whole grains are alike in terms of their benefits, and that federal law limits the claims that food companies can make about the benefits of whole grains in two important ways (the US Food and Drug Administration [FDA] regulates these claims).  First, there are unqualified claims, which have strong supporting evidence, but not necessarily unanimous agreement in the scientific community.  The second are qualified claims, in which the manufacturer can make a claim about the benefit of whole grains, as they related heart disease, for example, as long as the claim is backed by an authoritative scientific statement from a federal health agency or the National Academy of Sciences. 

Even amongst whole grains (whole wheat, oats, barley, etc.), the benefits are not uniform.  For example, the FDA has approved the claim that whole oats and whole barley can both lower cholesterol and reduce the risk of coronary artery disease (an unqualified claim), because they are both high in soluble fiber.  However, studies of whole wheat, for example do not show the same heart disease benefits.  Whole wheat, however, is generally good for you when it is part of a diet high in plant foods, because these kinds of foods help to reduce heart disease, as well as many cancers (a qualified claim).

So, when you choose whole grains (instead of refined carbohydrates, such breads or baked goods made with white flour), aim for grains that will help you achieve your particular health goals.  For example, if you specifically want to help control or lower your cholesterol, the only grains proven to do this, and carrying an FDA-approved claim for this benefit, are whole oats and whole barley.  Because of the obesity crisis, food labeling likely will get more complicated in the years to come, as regulators and manufacturers struggle with how to get the right kind of information into consumers’ hands at the point of purchase.  You can help yourself by building your label-reading skills now.  Look specifically for the amount of fiber in a whole grain product (at least 3 grams per serving is a good starting point) and the first ingredient listed…it should begin with the word ‘whole.’  And, it should have little or no added sugar (every 4 grams of added sugar is the equivalent of about 1 tsp of sugar). 

De Moura, F, et al.  Applying the FDA definition of whole grains to the evidence for cardiovascular disease health claims.  J. of Nutrition.  139: 2220S-2226S.  Supplement, published online September 23, 2009.

Might seem like an odd statement, but it is an important one in learning the differences between people who are normal weight, those who are overweight or obese, and those who successfully lose weight and keep it off. 

Researchers from four major universities and Pfizer studied how the brains of 51 adults responded to visual images of a wide variety of foods.  The study group included 18 people who were normal weight; 16 who were obese; and, 17 who had successfully lost weight (30 pounds or more and kept it off for at least three years).  The scientists displayed three kinds of images to each study subject: neutral images that would not stimulate a food-related response (i.e., trees, flower, rocks, etc.); low-energy density, nutrient-rich foods (whole grain cereals, fruit, salads, vegetables) and high-calorie, nutrient-poor foods (ice cream, hot dogs, French fries, cheeseburgers, cake, cookies).  While each subject viewed the images, an MRI machine took highly sophisticated images of his or her brain to see which areas activated and which ones did not.  The scientists theorized that visualization of a food (seeing it) is the first step in the process of deciding whether or not to eat, and that in each of these three groups, different parts of the brain would light up, indicating the potential interest in eating or control over consumption. 

They were right.  People who had successfully lost weight showed higher level of brain activity in the regions responsible for inhibition and control of behavior.  In other words, the parts of their brains that enabled them to not eat lit up, even more so than in normal weight people.  This finding is consistent with previous research showing the successful weight losers make a strong conscious effort to control their eating, track their consumption more diligently, workout more, and weigh themselves more often.

The brains of the obese adults lit up more in areas indicating that they were ready to respond to the visual food cue by eating.  They had relatively little activation of the brain areas responsible for inhibition of eating.

Your brain is much more plastic (trainable) than you think it is.  While our responses to food stimuli are very complex, it is clear that many of them are learned…from our friends and families, work and social environments, stress responses, advertising and marketing, etc.  If the way we respond to food is (in some measure) a learned behavior, it stands to reason that, with time and effort, we are capable of unlearning bad habits and learning new ones.  As Albert Einstein once said, “We cannot solve the problems created with our current pattern of thinking if we are not willing to change our current way of thinking.”  This study opens an important door on how the brain (which is where this whole process starts) parses those initial stimuli (such as the sight of food) and starts a cascade of responses that result either in eating or not eating.

Undoubtedly, Pfizer’s participation the study (the company did not pay for it) intimates their interest in pursuing a drug that may either help improve control of eating habits or dull the brain’s response to food stimulus.  However, you do not need to wait for (or eventually pay for) a new drug.  You can retrain your brain now, by leveraging the tools identified above that people who lose weight successfully use to their advantage: cut calorie intake, reduce the amount of fat calories in your diet, workout regularly and in increasing duration and intensity over time, weigh yourself, and strive to control passive eating.  Make conscious decisions about whether to eat or not eat and try not to eat reflexively.  No one thinks weight loss or weight maintenance is easy.  But, it is not as mysterious as the diet and supplement companies want you to believe.  We know what works and is safe and sustainable.  Make your brain work for you.  Start the retraining process today. 

Source: McCaffrey, JM, et al.  Differential functional MRI response to food pictures in successful weight loss maintainers relative to normal weight and obese controls.  Am. J. of Clinical Nutrition.  Oct. 2009. 90:4; 928-934.

The Archives of Internal Medicine this week published a study by Israeli scientists, showing that it truly is never too late to start exercise.  The team from Hadassah Hebrew University Medical Center followed 1,861 older adults (age 70 to 85) for 18 years, providing over 17,000 person-years of follow-up.  They wanted to know what difference regular physical activity made to the risk of death (from any cause) and to an adult’s ability to live independently.  The life preserving power of exercise was striking: at age 70, physically active adults reduced their risk of death by 39% compared to inactive adults; at age 78, physically active adults were 31% less likely to die; and, by age 85, they reduced their risk of death by 58%.  Importantly, regular physical activity was essential to living independently.  Active adults had fewer falls, joint problems, or loss of muscle function, and were much better able to perform activities of daily living.  This the first study to measure the impact of regular physical activity and risk of death in an older population for a long period.  Adults who started activity during the study got as much benefit as those who were active from the start. 

(Source: Stessman, J, et al.  Physical activity, function, and longevity among the very old.  Archives of Internal Medicine.  Sept. 14, 2009.  169:16; 1476-1483)

http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5834a6.htm?s_cid=mm5834a6_e

Click on the above link to see a chart just released from the Centers for Disease Control and Prevention about the proportion of American adults who participate in strength training regularly.  Shamefully, in no age group do more than 50% of either gender do so.  The trend line is especially troubling because the proportions decrease dramatically just when they should be increasing – through middle age into later life. 

The loss of muscle strength and mass should be regarded as a chronic illness itself.  Declining muscular strength increases your risk of nearly everything: high blood pressure, heart disease, diabetes, overweight, obesity, depression, arthritis…the list goes on.

Where are you on this chart?  Are you outperforming your peers or just going along with the pack and hoping that nothing goes wrong?  As for me, I have lifted weights consistently (2 to 4 x per  week) for 34 years.  At age 51, I still bench press about what I did in graduate school (about 280 pounds), which makes me stronger (adjusted for body weight) than 99% of men my age, and my muscle strength has helped me become a sound aerobic athlete.

Don’t be a lemming…build strength while the world around you gets progressively weaker.  You will be grateful that you did. 

Source: MMWR, Sept. 4, 2009

I recently had dinner with a pediatrician who is an expert in childhood obesity; she shared a terrific idea on how she teaches overweight kids to manage their daily calorie intake that will work just as well with adults: treat your calories as though they there were cash.  Say your daily goal is to eat 1,500 or fewer calories.  This means you start each day with $1,500 and each calorie is one dollar.  Every time you eat, you subtract the number of calories (dollars) for that meal.  Your goal is to finish the day with calories (dollars) left over, meaning that you did not use all your available calorie intake.  However, if you overeat, say you consume 1,700 calories, then you have to reduce the next day’s consumption by 200, to 1,300 calories, to bring yourself back into balance for this two-day period.  She told me that the kids she cares for love this approach and take to it instantly.

Give it a try to see if it helps you manage your calorie intake.  This method does not, obviously, take into account the calorie expenditure that comes from physical activity.  If you are physically active, and watching your intake, then you will create the daily calorie deficit necessary to produce weight loss.

The American Heart Association has released a new evidence-based guideline on how much added sugar Americans should have in their diets.  Added sugars are those added to processed foods, as well as the table sugar, honey, and syrups that we add to our foods when eating.  The recommendation excludes sugars that occur naturally in fruit, vegetables, and dairy products.  The AHA recommends that sedentary men eat no more than 150 calories per day (9.4 teaspoons) in the form of added sugars; the recommended limit is 100 calories per day for women (6.25 tsp).  On average, Americans eat 22 teaspoons of added sugar per day (355 calories) because of the volume of processed foods we consume.  Substitute water, a diet soda, or low-calorie/calorie-free sports drink for one 12 ounce sugared soda per day and you can eliminate 8 tsp. of sugar (130 calories).  This is a potential weight loss of 13.5 pounds in a year, without even accounting for increased physical activity and other wise dietary choices. 

If you are regularly physically active, you can increase these limits because your activity level gives you a greater margin for error.  This gives you the chance to consume more freely, and enjoy treats sensibly, while you simultaneously increase your fitness level through consistent, vigorous physical activity.  Take a look at the labels of the foods that you eat; you will undoubtedly be surprised to find added sugars everywhere, even in breads.  Over-consumption of added sugars is only part of the puzzle of energy imbalance, which also includes our increased consumption of fats and refined flours;  this overall rise in daily caloric intake, without more physical activity, increases the risk of overweight, obesity, diabetes, elevated blood triglycerides, and high blood pressure.

Source: Johnson, RK, et al.  Dietary sugars intake and cardiovascular health: a scientific statement from the American Heart Association.  Circulation.  Aug. 24, 2009.  Download the statement for free from: http://circ.ahajournals.org/cgi/content/abstract/CIRCULATIONAHA.109.192627v1?papetoc .

Data continue to emerge from large-scale studies around the world that lifestyle choices can literally make the difference between good and poor quality of life and, at the extremes, between life and death.  German researchers this week report on a nearly 8-year-long study of over 23,000 adults, looking at the impact of these four lifestyle habits: body mass index of less than 30; never smoking; at least 3.5 hours (210 minutes) per week of physical activity; and, health nutritional choices (lots of fruit, vegetables, whole grains, and little red meat).  People who had all four healthy lifestyle habits reduced their risk of developing diabetes or cancer or having a heart attack or stroke by about 80% compared to people who made none of these positive choices.  In this study, few people were at the extremes of the spectrum: 4% made none of these choices, but only 9% practiced all four positive lifestyle habits. 

Expressed another way, the scientists calculate that practicing all four positive lifestyle habits could prevent 75% of new diabetes cases, 45% of heart attacks, 18% of strokes, and 19% of cancer cases.  And, remember, diabetes is a powerful risk factor for cardiovascular disease; prevent diabetes, and you dramatically reduce the risk of heart attack or stroke.  With the exception of smoking cessation, which may be more likely with a formalized program or prescription drugs, these lifestyle choices are within your reach, with a modicum of planning, self-discipline and determination, and at very low cost.  Don’t try to do all four at once; be strategic and take small steps, building on each piece of progress that you make.  (Source: Ford, ES, et al.  Healthy living is the best revenge.  Archives of Internal Medicine.  Aug 10/24, 2009.  169:15; 1355-1362.)