An Ounce of Prevention
James Kenney
A fairly recent book, The Last Well Person, by Nortin M. Hadler, MD, seeks to help individuals understand the perils of the Western medical system – with its heavy emphasis on drugs and surgery.
Diet and lifestyle intervention can prove to be far superior to drugs and surgery in terms of longevity and quality of life. Why? Logically, the first step in preventing and usually treating a disease is to identify the cause of the disease, and eliminate the causal agents whenever possible. The causes of hypertension, atherosclerosis, obesity, type 2 diabetes and most common cancers have been largely identified. Poor diet, inactivity, smoking and heavy drinking are largely responsible for causing the diseases that kill most Americans.
Throughout the book, Hadler, who is a professor of medicine and microbiology/immunology at the University of North Carolina at Chapel Hill, builds the case that physicians today fail to meet the expectations and needs of their patients by relying on too many tests, procedures and drugs that drive up costs, but provide little health benefit.
Lower Cholesterol Increases Life Expectancy
Data from the Framingham Heart Study followed men in their 30s for 30 years. They found that those in the highest quartile of serum cholesterol levels in their 30s were more than twice as likely to be dead in their 60s compared to those with the lowest cholesterol!
• Treatment of high cholesterol levels with statin drugs only reduces cardiovascular disease (CVD) mortality by 20-30%. The drugs have only a negligible impact on total mortality, increasing life expectancy by just a few months after years of treatment.
• Atherosclerosis is not reversed by drugs in most people; whereas a very-low-fat, near-vegetarian diet has been shown to reverse atherosclerosis and dramatically cut the risk of dying.
• The treatment of coronary artery disease with angioplasty and bypass surgery does little or nothing to reduce one’s risk of dying from CVD and has no impact on longevity.
Diabetes Doubles Risk of Dying
People with type 2 diabetes are about twice as likely to die in any given year as those the same age with normal glucose tolerance. The figure below summarizes the best epidemiological data and indicates that at least 90% of all type 2 diabetes cases could probably be prevented with a healthier diet and lifestyle.
Cancers Can Be Prevented
Most of the common cancers (lung, breast, colon, ovarian, pancreatic, and prostate) are largely the result of smoking, inactivity, poor diet, weight gain, and/or heavy drinking. In a recent commentary in the Journal of the American Dietetic Association, Dr. Frank Hu states: “…the current overemphasis on pharmacologic treatment could lead to exaggeration of benefits of drug treatment in primary prevention and deflect attention from diet and lifestyle modifications.” Dr. Hu argues epidemiological and clinical trials strongly suggest that a healthy diet and lifestyle could cut the risk of developing many common cancers by about 70% or more. Dr. Hu also maintains a healthy diet and lifestyle could cut the risk having a heart attack or stroke by at least 70% and probably more.1
Death from Old Age
There is good data showing that the total mortality doubles in humans every 8 years and a large proportion of this increased risk of dying is a result of the aging process itself, something no drug or other medical intervention can impact.
However, a recent study that showed obese women appeared 9 years older biologically than those who were normal weight. This same study showed that women who smoked until they were 60 years old were also about 9 years “older” on average.
Bottom Line:
The benefits of a much healthier diet and lifestyle for reducing type 2 diabetes, cardiovascular diseases, many common cancers and many other ills are potentially far greater than drugs and surgeries.
By James J. Kenney, PhD, RD, FACN.
Reference:
1. JADA, November 2005, page 1718.
Thursday, April 8, 2010
Wednesday, April 7, 2010
Stress
Stress and Hormones
Stress can actually contribute to your risk of metabolic syndrome by increasing your body fat. When you're under stress, your body produces the hormone cortisol, which encourages the body to pack on fat, particularly around the abdomen. Manage your stress levels by cutting back on your responsibilities where you can, learning relaxation techniques and healthy ways to blow off steam, and making time for yourself to unwind. Getting at least seven hours of sleep a night will also go a long way toward relieving stress
Stress can actually contribute to your risk of metabolic syndrome by increasing your body fat. When you're under stress, your body produces the hormone cortisol, which encourages the body to pack on fat, particularly around the abdomen. Manage your stress levels by cutting back on your responsibilities where you can, learning relaxation techniques and healthy ways to blow off steam, and making time for yourself to unwind. Getting at least seven hours of sleep a night will also go a long way toward relieving stress
Tuesday, April 6, 2010
High Blood Pressure
90% Headed for Hypertension
James Kenney
Many people assume that if they have not been diagnosed with hypertension by the time they are 65 years old, they are out of the woods. Not so, according to a new study. Americans in their 50s, 60s and 70s who still have normal blood pressure should not feel very confident that hypertension is not in their future. What do we know so far? Earlier studies have shown that about 70% of all women age 65-75 have already developed hypertension, and by age 65 almost 80% of black women in the US have hypertension.1
New study shows 90% of Americans destined to develop hypertension
A recent study examined the residual lifetime risk of developing hypertension in men and women with normal blood pressure at age 55 or 65. Table 1 below shows the results of this new study.2 Consider these statistics:
• For people whose blood pressure is still within the normal range at age 55, over half will develop hypertension in the next 10 years and over 90% will develop hypertension in the next 25 years.
• For those lucky enough to make it to age 65 without being diagnosed with hypertension, about two in every three will develop hypertension within the next 10 years.
This data should serve as a wake-up call to many older Americans who have become complacent about their chances of developing hypertension.
What is the source of this false complacency?
Much of the confusion about the lifetime risk of developing hypertension can be traced to distorted information from the Salt Institute. The Salt Institute has claimed for many years that only about 20 to 25% of Americans have hypertension. This is true in a narrow sense, but very misleading since most of those without it today will eventually develop it.
They also claim that people do not need to avoid salt unless they already have hypertension and are also "salt-sensitive.” They maintain that most people with hypertension are not "salt-sensitive." This implies that about 90% of Americans have nothing to worry about when it comes to dietary salt. This is false.
The simple truth is that in every human population studied in which little or no salt was added to their diet, there was a virtual absence of hypertension.3 By contrast, in every human population group ever studied in which salt is customarily added to the diet, hypertension is common. Wherever salt is added to the diet, most people develop hypertension by the time they reach their 60th birthday.4
The rise in blood pressure with age in the US and all other modern societies led most doctors to believe that this was a normal part of the aging process. For many years doctors told their patients that a systolic blood pressure of up to 100 plus one's age was "normal." By contrast, most doctors always suspected that cigarette smoking caused most lung cancer and emphysema because these illnesses were far less common in their non-smoking versus smoking patients. However, nearly all Americans consume far too much salt. This means that doctors in the U.S. never see patients who don’t consume excessive salt. Further, the few doctors that did travel to far away lands were so struck by the absence of hypertension in older people where salt was not used that they came to believe that salt must be the primary causal agent causing hypertension.5
The bottom line
The more added salt from the saltshaker or processed foods is reduced in the diet the healthier Americans will become. Excessive dietary salt has been linked to hypertension, strokes, heart attacks and kidney failure but also to stomach, esophageal and kidney cancer. Osteoporosis, kidney stones, and headaches have also been tied in part to excessive dietary salt. The DASH-2 study proved that reducing sodium to 1500 mg per day reduced blood pressure more than reducing it to only 2400 mg in both normal and hypertensive subjects. The good news is that dramatically reducing salt intake will slow, stop or often reverse the cellular damage leading to these all too common health problems. The reduction in disease risk for those who cut out all salty foods can be as dramatic as the reduced risk of lung cancer, emphysema and heart disease in people who quit smoking.
By James J. Kenney, PhD, RD, LD, FACN
References:
1. Harvard Women's Health Watch. 1996;III:2-3
2. JAMA 2002;287:1003-10
3. Hypertension 1985;7:628-37
4. Am J Clin Nutr 1979;32(suppl):2659-62
5. The Hague: Martinus Nijhoff 1980:489-508
James Kenney
Many people assume that if they have not been diagnosed with hypertension by the time they are 65 years old, they are out of the woods. Not so, according to a new study. Americans in their 50s, 60s and 70s who still have normal blood pressure should not feel very confident that hypertension is not in their future. What do we know so far? Earlier studies have shown that about 70% of all women age 65-75 have already developed hypertension, and by age 65 almost 80% of black women in the US have hypertension.1
New study shows 90% of Americans destined to develop hypertension
A recent study examined the residual lifetime risk of developing hypertension in men and women with normal blood pressure at age 55 or 65. Table 1 below shows the results of this new study.2 Consider these statistics:
• For people whose blood pressure is still within the normal range at age 55, over half will develop hypertension in the next 10 years and over 90% will develop hypertension in the next 25 years.
• For those lucky enough to make it to age 65 without being diagnosed with hypertension, about two in every three will develop hypertension within the next 10 years.
This data should serve as a wake-up call to many older Americans who have become complacent about their chances of developing hypertension.
What is the source of this false complacency?
Much of the confusion about the lifetime risk of developing hypertension can be traced to distorted information from the Salt Institute. The Salt Institute has claimed for many years that only about 20 to 25% of Americans have hypertension. This is true in a narrow sense, but very misleading since most of those without it today will eventually develop it.
They also claim that people do not need to avoid salt unless they already have hypertension and are also "salt-sensitive.” They maintain that most people with hypertension are not "salt-sensitive." This implies that about 90% of Americans have nothing to worry about when it comes to dietary salt. This is false.
The simple truth is that in every human population studied in which little or no salt was added to their diet, there was a virtual absence of hypertension.3 By contrast, in every human population group ever studied in which salt is customarily added to the diet, hypertension is common. Wherever salt is added to the diet, most people develop hypertension by the time they reach their 60th birthday.4
The rise in blood pressure with age in the US and all other modern societies led most doctors to believe that this was a normal part of the aging process. For many years doctors told their patients that a systolic blood pressure of up to 100 plus one's age was "normal." By contrast, most doctors always suspected that cigarette smoking caused most lung cancer and emphysema because these illnesses were far less common in their non-smoking versus smoking patients. However, nearly all Americans consume far too much salt. This means that doctors in the U.S. never see patients who don’t consume excessive salt. Further, the few doctors that did travel to far away lands were so struck by the absence of hypertension in older people where salt was not used that they came to believe that salt must be the primary causal agent causing hypertension.5
The bottom line
The more added salt from the saltshaker or processed foods is reduced in the diet the healthier Americans will become. Excessive dietary salt has been linked to hypertension, strokes, heart attacks and kidney failure but also to stomach, esophageal and kidney cancer. Osteoporosis, kidney stones, and headaches have also been tied in part to excessive dietary salt. The DASH-2 study proved that reducing sodium to 1500 mg per day reduced blood pressure more than reducing it to only 2400 mg in both normal and hypertensive subjects. The good news is that dramatically reducing salt intake will slow, stop or often reverse the cellular damage leading to these all too common health problems. The reduction in disease risk for those who cut out all salty foods can be as dramatic as the reduced risk of lung cancer, emphysema and heart disease in people who quit smoking.
By James J. Kenney, PhD, RD, LD, FACN
References:
1. Harvard Women's Health Watch. 1996;III:2-3
2. JAMA 2002;287:1003-10
3. Hypertension 1985;7:628-37
4. Am J Clin Nutr 1979;32(suppl):2659-62
5. The Hague: Martinus Nijhoff 1980:489-508
Monday, April 5, 2010
When To Eat
When to Eat?
Q: Is it better to eat a meal before or after a workout? Why?
A: Both. Here's what I like to do: have my breakfast at 9 a.m., work out from 10:30 to 12, and eat by 1 p.m. Here's why:
Back in the old days, people thought they should train on an empty stomach in order to burn more fat, but that has turned out to be FALSE. In fact, your body needs some glucose (blood sugar) for fuel in addition to what it can use from fat stores when you're working out. If you don't have any blood sugar available, your body will eat the muscles' glycogen, or stored glucose it. Low blood sugar will also make you tired and sluggish during your training session. For these reasons, I suggest you eat something 45 minutes to an hour before training — you'll have more energy and endurance to work harder, burn more calories, and improve your muscle tone.
After training, during a period known as the golden hour (45 to 60 minutes after a workout), muscles absorb the most nutrients, and glycogen is replaced the most efficiently. You don't have to have a huge meal — just a little something that contains both protein and carbs will give the best results.
Throw Out Your Junk Food
That's right — go through your kitchen and get rid of all the junk food and processed garbage immediately. Why? Because you can't eat it if it's not there! And don't go out and buy more of that stuff, either. Just eliminate it from your kitchen entirely. Even if you have to put up with a little whining from the kids or your spouse or whomever, just remember, you're not the only one who's going to be better off not eating that crap. Reacquaint yourself with the local supermarket; find the healthy sections, and try to avoid the snack food, junk food, and ice cream aisles. Avoid any foods that make you feel powerless.
Q: Is it better to eat a meal before or after a workout? Why?
A: Both. Here's what I like to do: have my breakfast at 9 a.m., work out from 10:30 to 12, and eat by 1 p.m. Here's why:
Back in the old days, people thought they should train on an empty stomach in order to burn more fat, but that has turned out to be FALSE. In fact, your body needs some glucose (blood sugar) for fuel in addition to what it can use from fat stores when you're working out. If you don't have any blood sugar available, your body will eat the muscles' glycogen, or stored glucose it. Low blood sugar will also make you tired and sluggish during your training session. For these reasons, I suggest you eat something 45 minutes to an hour before training — you'll have more energy and endurance to work harder, burn more calories, and improve your muscle tone.
After training, during a period known as the golden hour (45 to 60 minutes after a workout), muscles absorb the most nutrients, and glycogen is replaced the most efficiently. You don't have to have a huge meal — just a little something that contains both protein and carbs will give the best results.
Throw Out Your Junk Food
That's right — go through your kitchen and get rid of all the junk food and processed garbage immediately. Why? Because you can't eat it if it's not there! And don't go out and buy more of that stuff, either. Just eliminate it from your kitchen entirely. Even if you have to put up with a little whining from the kids or your spouse or whomever, just remember, you're not the only one who's going to be better off not eating that crap. Reacquaint yourself with the local supermarket; find the healthy sections, and try to avoid the snack food, junk food, and ice cream aisles. Avoid any foods that make you feel powerless.
Saturday, April 3, 2010
Sugar
Hidden Sources of Sugar
Let's get something straight — I want you to stay far, far away from high-fructose corn syrup (HFCS). Seriously, this stuff really puts the "junk" in junk food! It's the most abundant source of calories in a lot of foods out there and it's terrible for you because it boosts your fat-storing hormones. Look at your labels and you'll find HFCS in so many foods that line the shelves in our grocery stores. But just because high-fructose corn syrup is evil doesn't necessarily mean halos are hovering over other sugars. There's more sweet stuff out there that you need to avoid!
We still have far too much of the noncorn variety of sugar in our diets, and it's definitely not doing anything good for our health or our waistlines. The average American eats more than 30 teaspoons of sugar a day — that's more than 114 pounds of sugar a year!
While sugar is everywhere, you must do your best to eat it in extreme moderation. The World Health Organization recommends no more than 12 to 15 teaspoons a day, or 48 to 60 grams. I prefer that you keep the amount as low as possible. Check your food labels — anything with "sugar" should obviously be avoided. However, sugar has many aliases. I'll give you a hint: Anything that ends in "-ose" is a sugar. See what I mean in the list below, and beware of these sweeteners in the foods you eat!
Dextrose
Evaporated cane juice
Fructose
Fruit juice concentrates
Galactose
Glucose
Honey
Invert corn syrup
Lactose
Malt
Maltose
Malt syrup
Maple syrup
Molasses
Rice syrup
Sucrose
Sugar in Fruit
Want to avoid wild blood sugar spikes? Eat whole fruits instead of fruit juices. Not only will they help your blood sugar stay in check, you'll also get beneficial fiber from the whole fruits as well. Just be aware that some fruits are high in sugar — even though they're nutritious and relatively low in calories. Some of the highest-sugar fruits are mangoes, pineapples, and bananas. I'm not saying to avoid these. (Trust me, you'd have to eat more fruit than you can imagine for it to be deemed unhealthy.) However, if you've been diagnosed with prediabetes or diabetes, it's time to limit your intake. If you want to eat fruits with less sugar, go for berries, tomatoes, and oranges.
Let's get something straight — I want you to stay far, far away from high-fructose corn syrup (HFCS). Seriously, this stuff really puts the "junk" in junk food! It's the most abundant source of calories in a lot of foods out there and it's terrible for you because it boosts your fat-storing hormones. Look at your labels and you'll find HFCS in so many foods that line the shelves in our grocery stores. But just because high-fructose corn syrup is evil doesn't necessarily mean halos are hovering over other sugars. There's more sweet stuff out there that you need to avoid!
We still have far too much of the noncorn variety of sugar in our diets, and it's definitely not doing anything good for our health or our waistlines. The average American eats more than 30 teaspoons of sugar a day — that's more than 114 pounds of sugar a year!
While sugar is everywhere, you must do your best to eat it in extreme moderation. The World Health Organization recommends no more than 12 to 15 teaspoons a day, or 48 to 60 grams. I prefer that you keep the amount as low as possible. Check your food labels — anything with "sugar" should obviously be avoided. However, sugar has many aliases. I'll give you a hint: Anything that ends in "-ose" is a sugar. See what I mean in the list below, and beware of these sweeteners in the foods you eat!
Dextrose
Evaporated cane juice
Fructose
Fruit juice concentrates
Galactose
Glucose
Honey
Invert corn syrup
Lactose
Malt
Maltose
Malt syrup
Maple syrup
Molasses
Rice syrup
Sucrose
Sugar in Fruit
Want to avoid wild blood sugar spikes? Eat whole fruits instead of fruit juices. Not only will they help your blood sugar stay in check, you'll also get beneficial fiber from the whole fruits as well. Just be aware that some fruits are high in sugar — even though they're nutritious and relatively low in calories. Some of the highest-sugar fruits are mangoes, pineapples, and bananas. I'm not saying to avoid these. (Trust me, you'd have to eat more fruit than you can imagine for it to be deemed unhealthy.) However, if you've been diagnosed with prediabetes or diabetes, it's time to limit your intake. If you want to eat fruits with less sugar, go for berries, tomatoes, and oranges.
Friday, April 2, 2010
Warming Up and Cooling Down
How to Warm Up and Cool Down
Q: What do you suggest for warm-up and cool-down exercises?
A: The best kind of warm up before a tough workout is a few minutes of cardio (such as jumping rope or jumping jacks) followed by dynamic stretching. We were taught years ago to sit or stand and stretch one muscle group at a time. Contrary to popular belief, this kind of static stretching — which helps prevent muscle soreness and improves flexibility — is best performed AFTER a workout, when your muscles are very warm and loose.
In the past several years, fitness experts have discovered that there is a much more effective and healthy way to stretch BEFORE a workout: the dynamic stretch. Dynamic stretching is basically stretching with motion, so your body gets a chance to warm up the muscles slowly and in a functional way. It's a 1-2-3 punch: You warm up your body, get your heart rate up, and stretch all at the same time!
Below are some examples of dynamic stretches. Do them on a level surface for a total of about five minutes before you begin your workout. You will notice that with time the exercises will become easier and they will help improve your coordination, flexibility, and balance. Start by performing the exercises over a distance of about 30 yards; increase to 50 yards as you get more comfortable.
High-Knee Walking
Purpose: To bend your hips and knees, stretch your glutes and hamstrings, and warm up your arms and calves.
The stretch: Take an exaggeratedly high step, driving your knee as high as possible, and simultaneously drive your opposite elbow forward. Make sure that you push up onto your toes so that your calf gets involved. Use a normal running arm motion, with a 90-degree angle at the elbow; elbow goes from chin level to as far back as possible while maintaining forward straight posture.
Key points: Drive your knees up as high as possible; get up as high as you can on your toes; and drive your arms with each step.
Deep Side Lunge
Purpose: To bend your hips and knees, and stretch your glutes and your groin.
The stretch: Keep your torso upright and take a wide step out to the side. Lower your body so you are in the sumo squat position. Recover by bringing your feet together and standing upright. Never cross your feet. Keep your hands on your hips.
Key point: The lower you lunge, the greater stretch you will achieve.
Trunk Rotation
Purpose: To stretch your lower back.
The stretch: Stand with your hands on your hips. Place your feet shoulder-width apart, toes pointing straight in front of you. Rotate from the waist to the right, then left. Go as far as you can while keeping your feet in the same position. Do the rotation about 25 times.
Key point: Start slowly; as you get going, you can go a little faster, with more rotation.
Butt Kicks
Purpose: To stretch your quads.
The stretch: This can be done walking or jogging. As you walk or jog, exaggerate the knee bend so that you are trying to kick yourself in the butt. You want your knee to point straight to the ground as your heel comes toward your butt. Keep your arms pumping in the normal running motion.
Key point: The higher you get your heel and the more you keep your knee toward the ground (instead of coming up in front of you with hip flexion), the more of a quad stretch you'll get.
Arm Swing
Purpose: To stretch your pecs and loosen your upper back.
The stretch: Stand with your feet shoulder-width apart. Raise your arms out to your sides and swing them forward, crossing one over the other, so that you hug yourself, then open them up and out to the sides so you feel a stretch in the front of your shoulders. Keep your stomach tight as you do this exercise and start slowly. Increase your speed and range of motion as you get warmed up. Repeat about 30 times.
Key point: Cross your arms right over left and then left over right so you get equal stretching on both sides.
Attention, Clock-watchers!
When you're working out, how many of you watch the clock? Trust me, I know how it is — I'm one of you. But I want you to try something. Next time you're working out, cover up the clock. Instead of focusing on how you have another 10 minutes to go and you feel like killing yourself, focus on the workout, how your body feels, and how great it is that you're getting fit. Use the time and energy to empower yourself. The worst thing that could happen is you end up running a little over!
Q: What do you suggest for warm-up and cool-down exercises?
A: The best kind of warm up before a tough workout is a few minutes of cardio (such as jumping rope or jumping jacks) followed by dynamic stretching. We were taught years ago to sit or stand and stretch one muscle group at a time. Contrary to popular belief, this kind of static stretching — which helps prevent muscle soreness and improves flexibility — is best performed AFTER a workout, when your muscles are very warm and loose.
In the past several years, fitness experts have discovered that there is a much more effective and healthy way to stretch BEFORE a workout: the dynamic stretch. Dynamic stretching is basically stretching with motion, so your body gets a chance to warm up the muscles slowly and in a functional way. It's a 1-2-3 punch: You warm up your body, get your heart rate up, and stretch all at the same time!
Below are some examples of dynamic stretches. Do them on a level surface for a total of about five minutes before you begin your workout. You will notice that with time the exercises will become easier and they will help improve your coordination, flexibility, and balance. Start by performing the exercises over a distance of about 30 yards; increase to 50 yards as you get more comfortable.
High-Knee Walking
Purpose: To bend your hips and knees, stretch your glutes and hamstrings, and warm up your arms and calves.
The stretch: Take an exaggeratedly high step, driving your knee as high as possible, and simultaneously drive your opposite elbow forward. Make sure that you push up onto your toes so that your calf gets involved. Use a normal running arm motion, with a 90-degree angle at the elbow; elbow goes from chin level to as far back as possible while maintaining forward straight posture.
Key points: Drive your knees up as high as possible; get up as high as you can on your toes; and drive your arms with each step.
Deep Side Lunge
Purpose: To bend your hips and knees, and stretch your glutes and your groin.
The stretch: Keep your torso upright and take a wide step out to the side. Lower your body so you are in the sumo squat position. Recover by bringing your feet together and standing upright. Never cross your feet. Keep your hands on your hips.
Key point: The lower you lunge, the greater stretch you will achieve.
Trunk Rotation
Purpose: To stretch your lower back.
The stretch: Stand with your hands on your hips. Place your feet shoulder-width apart, toes pointing straight in front of you. Rotate from the waist to the right, then left. Go as far as you can while keeping your feet in the same position. Do the rotation about 25 times.
Key point: Start slowly; as you get going, you can go a little faster, with more rotation.
Butt Kicks
Purpose: To stretch your quads.
The stretch: This can be done walking or jogging. As you walk or jog, exaggerate the knee bend so that you are trying to kick yourself in the butt. You want your knee to point straight to the ground as your heel comes toward your butt. Keep your arms pumping in the normal running motion.
Key point: The higher you get your heel and the more you keep your knee toward the ground (instead of coming up in front of you with hip flexion), the more of a quad stretch you'll get.
Arm Swing
Purpose: To stretch your pecs and loosen your upper back.
The stretch: Stand with your feet shoulder-width apart. Raise your arms out to your sides and swing them forward, crossing one over the other, so that you hug yourself, then open them up and out to the sides so you feel a stretch in the front of your shoulders. Keep your stomach tight as you do this exercise and start slowly. Increase your speed and range of motion as you get warmed up. Repeat about 30 times.
Key point: Cross your arms right over left and then left over right so you get equal stretching on both sides.
Attention, Clock-watchers!
When you're working out, how many of you watch the clock? Trust me, I know how it is — I'm one of you. But I want you to try something. Next time you're working out, cover up the clock. Instead of focusing on how you have another 10 minutes to go and you feel like killing yourself, focus on the workout, how your body feels, and how great it is that you're getting fit. Use the time and energy to empower yourself. The worst thing that could happen is you end up running a little over!
Thursday, April 1, 2010
Diet, Exercise and Cancer Risk
Diet, Exercise and Cancer Risk
In November 2007, the results of an expert panel reviewing the scientific evidence linking diet and other lifestyle factors to the development of various types of cancer was published. This distinguished panel of experts was put together by the American Institute of Cancer Research and the World Cancer Research Fund to review more than 7,000 published studies. The final report is on line at dietandcancerreport.org and is 537 pages. The report contains no real surprises but does provide a useful summary of the strength of the research linking various dietary and lifestyle factors to the development of all the most common types of cancer.
The panel’s recommendations included:
• Limiting the consumption of salt, alcohol and red and processed meats
• Consuming mostly minimally processed foods of plant origin
• Being as lean as possible within the normal range.
• To avoid excess body fat, the panel recommended people be active daily and avoid sugar-rich drinks and calorie-dense foods, which promote excessive energy intake and weight gain over time.
Research in numerous animal species has consistently shown the most powerful dietary measure for dramatically reducing the risk of most cancers is a reduction in energy intake.
Research in studies with people show that weight gain increases the amount of growth factors, anabolic hormones, and inflammatory substances while reducing the levels of sex-hormone binding proteins (SHBP). All of these risk factors are associated with an increased risk of numerous cancers in people.1
Growing data suggests that one of the most potent promoters of cell growth and cancer development is insulin-like growth factor-1 (IGF-1). Weight gain, increased calorie intake, and increased protein intake increase IGF-1 levels in short-term studies.
It is difficult to do long-term studies in people because long-term compliance with diet and exercise recommendations is generally not good.
To get around this problem researchers examined 3 groups of people. The control group followed a typical modern diet and were moderately overweight (mean BMI = 26.70). By contrast, the two other groups of subjects were thin by modern standards either because they were following a low calorie/low protein diet high in fiber or because they were long-term endurance runners (BMI = 21.3 and 21.1, respectively).
Compared to the control subjects both the endurance runners and those consuming a low protein and low calorie diet had levels of numerous plasma components associated with a reduced risk of cancer and longevity in animals.
However, while the IGF-1 levels were somewhat lower in the endurance runners than the control group, IGF-1 levels were not nearly as low in the runners as they were in those following the low calorie, low protein and higher fiber diet.2
Bottom Line:
There is no doubt that remaining thin, regular exercise and a healthful, low-calorie diet all help prevent numerous types of cancer in people. Increasing research in animals and people suggests that a low calorie dense diet consisting mostly of minimally processed plant foods is best for reducing calorie intake. Fewer calories appears to be the single most important way to cut the risk of cancer and increase longevity.
By James J. Kenney, Ph.D., RD, FACN
References
1. Nat Rev Cancer 2004;4:579-91
2. Am J Clin Nutr 2006;84:1456-62
In November 2007, the results of an expert panel reviewing the scientific evidence linking diet and other lifestyle factors to the development of various types of cancer was published. This distinguished panel of experts was put together by the American Institute of Cancer Research and the World Cancer Research Fund to review more than 7,000 published studies. The final report is on line at dietandcancerreport.org and is 537 pages. The report contains no real surprises but does provide a useful summary of the strength of the research linking various dietary and lifestyle factors to the development of all the most common types of cancer.
The panel’s recommendations included:
• Limiting the consumption of salt, alcohol and red and processed meats
• Consuming mostly minimally processed foods of plant origin
• Being as lean as possible within the normal range.
• To avoid excess body fat, the panel recommended people be active daily and avoid sugar-rich drinks and calorie-dense foods, which promote excessive energy intake and weight gain over time.
Research in numerous animal species has consistently shown the most powerful dietary measure for dramatically reducing the risk of most cancers is a reduction in energy intake.
Research in studies with people show that weight gain increases the amount of growth factors, anabolic hormones, and inflammatory substances while reducing the levels of sex-hormone binding proteins (SHBP). All of these risk factors are associated with an increased risk of numerous cancers in people.1
Growing data suggests that one of the most potent promoters of cell growth and cancer development is insulin-like growth factor-1 (IGF-1). Weight gain, increased calorie intake, and increased protein intake increase IGF-1 levels in short-term studies.
It is difficult to do long-term studies in people because long-term compliance with diet and exercise recommendations is generally not good.
To get around this problem researchers examined 3 groups of people. The control group followed a typical modern diet and were moderately overweight (mean BMI = 26.70). By contrast, the two other groups of subjects were thin by modern standards either because they were following a low calorie/low protein diet high in fiber or because they were long-term endurance runners (BMI = 21.3 and 21.1, respectively).
Compared to the control subjects both the endurance runners and those consuming a low protein and low calorie diet had levels of numerous plasma components associated with a reduced risk of cancer and longevity in animals.
However, while the IGF-1 levels were somewhat lower in the endurance runners than the control group, IGF-1 levels were not nearly as low in the runners as they were in those following the low calorie, low protein and higher fiber diet.2
Bottom Line:
There is no doubt that remaining thin, regular exercise and a healthful, low-calorie diet all help prevent numerous types of cancer in people. Increasing research in animals and people suggests that a low calorie dense diet consisting mostly of minimally processed plant foods is best for reducing calorie intake. Fewer calories appears to be the single most important way to cut the risk of cancer and increase longevity.
By James J. Kenney, Ph.D., RD, FACN
References
1. Nat Rev Cancer 2004;4:579-91
2. Am J Clin Nutr 2006;84:1456-62
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