Category Archives: Longevity

What’s More Important For Longevity: Level of Fitness Or Minutes of Exercise Per Week?

She can increase intensity by increasing the weight of those dumbbells

She can increase intensity by increasing the weight of those dumbbells

You’ve heard that “sitting is the new smoking,” right?

Regular physical activity prevents disease and prolongs life. But if you nevertheless still spend to much time sitting around either at work or home, the sitting tends to counteract the benefits of your exercise.

A new study says that your fitness level is more important for long-term health than the number of hours you exercise. Fitness level in this context was cardiorespiratory fitness, probably measured by a maximal-effort treadmill or bicycle test.

Some of your fitness level is inherited, but you can also improve your fitness with the proper intensity or duration of exercise. Rather than exercise longer, I prefer more intensity. Just strolling around the mall at 2 mph for two hours isn’t going to improve fitness in most folks.

From MNT:

“The team conducted a cross-sectional study of 495 women and 379 men from Norway aged between 70-77 years. Sedentary time and physical activity were assessed by accelerometers, while cardiorespiratory fitness was determined by peak oxygen uptake (VO2 peak) – the measurement of the volume of oxygen that the body can utilize during physical exertion.

Researchers compared different levels of activity with fitness levels and cardiovascular risk factor clusters. A cardiovascular risk factor cluster was defined as the presence of three to five risk factors for heart disease.

These risk factors included: elevated waist circumference, elevated blood triglycerides or reduced “good” cholesterol levels, high blood pressure or treatment for hypertension, and elevated fasting blood sugar levels – combined symptoms commonly referred to as metabolic syndrome.

High cardiorespiratory fitness reduced risk of heart diseaseFindings – published in Mayo Clinic Proceedings – showed that when compared with women and men who were the least sedentary, women and men from the most sedentary group were 83 percent and 63 percent more likely to have cardiovascular risk factors from extended time sitting, respectively.

However, when the team took participants’ level of fitness into consideration – measured by having high age-specific cardiorespiratory fitness – they found that the fittest 40 percent had a decreased likelihood of cardiovascular risk factors from prolonged sitting.This finding held true even though the fittest participants spent between 12-13 hours per day sedentary and did not meet current moderate to vigorous physical activity guidelines.”

Source: Fitness, not physical activity, mitigates negative effects of prolonged sitting – Medical News Today

PS: If you’re new to exercise, I teach you how to get started in my books.

Living at Higher Altitude May Prolong Life

Adult life is a battle against gravity. Eventually we all lose.

Adult life is a battle against gravity. Eventually we all lose.

From P.D. Mangan:

“Death rates from both of these cancers [breast in women, colon in men] were about half as high at an altitude of greater than 1000 meters (3300 feet).  The study also found about a 30% reduction in deaths from coronary artery disease at >1000 meters.

This accords well with a number of other studies. For example, “Lower Mortality From Coronary Heart Disease and Stroke at Higher Altitudes in Switzerland“. This study found 22% less heart disease death for every +1000 meters in altitude, and 12% less stroke death.

Association Between Alzheimer Dementia Mortality Rate and Altitude in California Counties“: This study found about half the death rate from Alzheimer’s at an altitude of 1600 meters vs that at sea level.

There’s less diabetes at high altitude.”

Source: Higher Altitude Means Much Lower Death Rates – Rogue Health and Fitness

RTWT.

Intensive Program Extended Life By Eight Years in T2 Diabetes

MedPageToday has some details:

“Type-2 diabetics lived nearly 8 years longer when treated with an intensive, multifactorial approach that employed behavioral and pharmacological interventions.

The 160 patients with type-2 diabetes mellitus and microalbuminuria, now followed for 21 years, received either conventional or intensified therapy.

Thirty-eight intensive-therapy patients died during the follow-up period compared with 55 conventional-therapy patient deaths during the same time. This translated to a median survival period 7.9 years longer for the intensive-therapy cohort, as well as a median delay of 8.1 years to a first cardiovascular event, the investigators reported in the journal Diabetologia.

“The outcome of our study is very encouraging and emphasizes the need for early and intensified treatment of multiple modifiable risk factors for a poor prognosis of patients with type 2 diabetes,” said lead study author Peter Gaede, MD, of the University of Southern Denmark in Odense, in a statement.”

Source: Intensive Program Extends Lifespan in T2D Patients | Medpage Today

Parker here.

Study participants were northern Europeans (Danes) who had small amounts of protein (albumin) in their urine and were mostly in their 50s when the long-term study started.

Medical intervention included diet changes, drugs for diabetes/blood pressure/lipids, and exercise. Therapy for the intensive therapy group was “target-driven, with stepwise implementation of both behavioral and pharmacological treatment following a structured approach.”

If you’re a researcher and want to test how my diabetes diets would perform in a study like this, contact me for a discount on books.

Steve Parker, M.D.

DietDoctor Shares More Practical Tips for Fasting 

This guy had long spans of time between meals, perhaps days

This guy had long spans of time between meals, perhaps days

Yet another good post from DietDoctor! Why fast? Among many reasons is that fasting turns on autophagy, which helps clear the debris of daily living out of your cells, probably leading to longer life.

Click here for P.D. Mangan’s post on fasting and autophagy.

Dr. Fung at DietDoctor also warns about the danger of hypoglycemia for certain folks with diabetes. Read that part carefully.

Anyway, here are Dr. Fung’s top eight tips:

“Drink water: Start each morning with a full eight-ounce glass of water.

Stay busy: It’ll keep your mind off food. It often helps to choose a busy day at work for a fast day.

Drink coffee: Coffee is a mild appetite suppressant. Green tea, black tea, and bone broth may also help.Ride the waves: Hunger comes in waves; it is not continuous. When it hits, slowly drink a glass of water or a hot cup of coffee. Often by the time you’ve finished, your hunger will have passed.

Don’t tell anybody you are fasting: Most people will try to discourage you, as they do not understand the benefits. A close-knit support group is often beneficial, but telling everybody you know is not a good idea.

Give yourself one month: It takes time for your body to get used to fasting. The first few times you fast may be difficult, so be prepared. Don’t be discouraged. It will get easier.

Follow a nutritious diet on non-fast days: Intermittent fasting is not an excuse to eat whatever you like. During non-fasting days, stick to a nutritious diet low in sugars and refined carbohydrates.

Don’t’ binge: After fasting, pretend it never happened. Eat normally, as if you had never fasted.”

Source: More Practical Tips for Fasting – Diet Doctor

Steve Parker, M.D.

PS: I don’t feature fasting in any of my books, but I’ve gradually come around to seeing the potential benefits.

Obesity Paradox Resolved?

Not familiar with the obesity paradox? Read about it at Wikipedia, which may or may not be accurate.

From a recent article at MPT:

“A massive meta-analysis pooling data from millions of people in several countries reaffirmed that body mass index (BMI) has a J-shaped relationship with mortality, with the lowest death rates among those in the traditional “normal” range of 20-25.

The study of nearly four million people revealed that those in every BMI category above and below the normal range had significantly higher mortality rates.The elevation in risk applied to even mildly overweight people, and was highest for those with overt obesity, according to researchers with the Global BMI Mortality Collaboration, a part of the University of Cambridge.”

***

“Our results challenge recent suggestions that overweight and moderate obesity are not associated with higher mortality, bypassing speculation about hypothetical protective metabolic effects of increased body fat in apparently healthy individuals,” wrote the authors. Their data showed the J-shaped relationship maintained for every age group, albeit attenuated somewhat among those in the 70-89 age range.”

Source: Study: Higher BMI Signals Earlier Death | Medpage Today

Accidents Replace Stroke as 4th Leading Cause of Death in U.S.

Nothing to do with accidents

Nothing to do with accidents

For most of my medical career, stroke was the third leading cause of death in the U.S., behind heart disease and cancer. Just a few years ago, chronic lower respiratory tract disease surpassed stroke.

Stroke continues to fall in rank and fell recently to fifth place, overtaken by accidents (unintentional injuries).

Even non-fatal strokes can be devastating.

Reduce your risk of stroke by maintaining normal blood pressure, not smoking, exercise regularly, living at a healthy weight, limiting your alcohol consumption, don’t get diabetes, and limit your age to 55. It’s also important to seek medical attention if you have a TIA (transient ischemic attack).

I wouldn’t be surprised if the paleo diet helps prevent stroke, but we don’t have much evidence yet.

Steve Parker, M.D.

Paleobetic Diet-FrontCover_300dpi_RGB_5.5x8.5

Obesity Soon to Affect Average Life Span in U.S.

That excess weight can shorten your life

That excess weight can shorten your life

“The medical community seems to be under a fog that we can constantly and forever reduce death rates, and that’s simply not true,” said Professor Olshansky, who published a study in 2012 showing that life spans for white women without a high school diploma had declined, a rare event in developed countries.

“You need to look at the health status of the living,” not the mortality statistics of the dead, he said, adding that obesity is afflicting younger generations in a way that will eventually make the numbers worse.

RTWT at The New York Times. 

Do something about your obesity before it’s too late.

Steve Parker, M.D.

 

Paleobetic Diet-FrontCover_300dpi_RGB_5.5x8.5

Book Review: “Stop the Clock: The Optimal Anti-Aging Strategy”

dementia, memory loss, Mediterranean diet, low-carb diet, glycemic index, dementia memory loss

“I wish we could have read PD Mangan’s book thirty years ago!”

I read P.D. Mangan’s 2015 book, Stop the Clock: The Optimal Anti-Aging Strategy. I give it five stars in Amazon’s rating system. High recommended.

♦   ♦   ♦

I approached this book with trepidation. I like PD Mangan even though I’ve never met him. We’ve interacted on Twitter and at our blogs. You can tell from his blogging that he’s very intelligent. I don’t know his educational background but wouldn’t be surprised if he has a doctorate degree. My apprehension about the book is that I was concerned it would be brimming with malarkey and scams. Fortunately, that’s not the case at all.

Twin studies have established that 25% of longevity is genetic. That leaves a lot of lifestyle factors for us to manipulate.

I’m not familiar with the anti-aging scientific literature and don’t expect it will ever be something I’ll spend much time on. But it’s an important topic. I’ll listen to what other smart analysts—like Mr. Mangan—have to say about it.

It’s quite difficult to do rigorous testing of anti-aging strategies on free-living humans. So the best studies we have were done with worms, rodents, and monkeys; the findings may or may not apply to us. For example, long-term calorie restriction—about 30% below expected energy needs—is known to prolong life span in certain worms and rodents, with mixed results in rhesus monkeys. It’s the rare person who would follow such a low-calorie diet for years as an experiment. I doubt I would do it even if proven to give me an extra five years of life. I like to eat.

There are several prominent theories of how and why animals age. The author thinks the major factors are:

  1. oxidative stress
  2. inflammation
  3. a decline in autophagy (perhaps most important)

An effective anti-aging program should address these issues.

In the anti-aging chapter of his book, The South Asian Health Solution, internist Ronesh Sinha says that “Lifestyle practices that reduce excess inflammation in the body will help delay the aging process.” Dr. Sinha is a huge exercise advocate and low-carb diet proponent.

Mr. Mangan makes a convincing argument that a good way to forestall aging is to apply hormetic stress. Hormesis is a phenomenon whereby a beneficial effect (e.g., improved health, stress tolerance, growth, or longevity) results from exposure to low doses of an agent or activity that is otherwise toxic or lethal when given at higher doses.

Needs a bit more hormetic stress

Needs a bit more hormetic stress

In case you’re not familiar with hormesis, here’s a major example. Lack of regular exercise leads is linked to premature death from heart disease and cancer. Starting and maintaining an exercise program leads to greater resistance to injury and disease and longer life span. On the other hand, too much exercise is harmful to health and longevity. We see that in professional athletes and excessive marathon runners. Something about exercise—in the right amount—enhances the body’s intrinsic repair mechanisms. That’s the hormetic effect of exercise; one mechanism is by turning on autophagy.

Autophagy is the body’s natural process for breaking down and removing or recycling worn-out cellular structures. This wearing-out occurs daily and at all ages.

If you’re thinking Mr. Mangan recommends exercise as an anti-aging strategy, you’re exactly right. Especially resistance training and high intensity training. His specific recommendations are perfectly in line with what I tell my patients.

Calorie restriction is another form of hormesis; the body reacts by up-regulating stress defense mechanisms. As a substitute for calorie restriction, the author recommends intermittent fasting. Intermittent fasting increases insulin sensitivity, which leads to enhanced autophagy. Fasting seems perfectly reasonable if you think about it, which very few do. Many of us eat every three or four hours while awake, whether a meal or a snack. If you think about it, that’s not a pattern that would be supported by evolution. In the Paleolithic era, we often must have gone 12–16 hours or even several days without food. Hominins without the resiliency to do that would have died off and not passed their genes down to us.

Steve Parker MD, Advanced Mediterranean DIet

Naturally low-carb Caprese salad: mozzarella cheese, tomatoes, basil, extra virgin olive oil

Another anti-aging trick is a low-carb diet, defined as under 130 grams/day, or under 20% of total calories. It may work via insulin signaling and weight control.

Glutathione within our cells is a tripeptide antioxidant critical for clearing harmful reactive oxygen species (free radicals). We need adequate glutathione to prevent or slow aging. Cysteine is the peptide that tends to limit our body’s production of glutathione. We increase our cysteine supply either through autophagy (which recycles protein peptides) or diet. Dietary sources of cysteine are proteins, especially from animal sources. Whey protein supplements and over-the-counter n-acetyl cysteine are other sources. Fasting is another trick that increases cysteine availability via autophagic recyling.

I don’t recall the author ever mentioning it, but if you hope to maximize longevity, don’t smoke. Even if it has hormetic effects. Maybe that goes without saying in 2015.

When I read a book like this, I always run across tidbits of information that I want to remember. Here are some:

  • those of us in the top third of muscular strength have a 40% lower risk of cancer (NB: you increase your strength through resistance training not aerobics)
  • exercise helps prevent cognitive decline and dementia, at least partially via enhanced autophagy
  • exercise increases brain volume (in preparing to do this review I learned that our brains after age 65 lose 7 cubic centimeters of volume yearly)
  • optimal BMI may be 20 or 21, not the 18.5-25 you’ll see elsewhere (higher BMI due to muscle mass rather than fat should not be a problem)
  • Scientist Cynthia Kenyon: “Sugar is the new tobacco.” (in terms of aging)
  • phytochemicals (from plants, by definition) activate AMPK, a cellular energy sensor that improves stress defense mechanisms and increases metabolic efficiency
  • curcumin (from the spice turmeric) activates AMPK
  • coffee promotes autophagy
  • he does not favor HGH supplementation
  • in the author’s style of intermittent fasting, you’re not reducing overall calorie intake, just bunching your calories together over a shorter time frame (e.g., all 2,500 calories over 6-8 hours instead of spread over 24)
  • mouse studies suggest that intermittent fasting could reduce risk of Alzheimer’s disease and Parkinsons disease
  • consider phytochemical supplements: curcumin, resveratrol, green tea extract
  • calorie-restriction mimetics include resveratrol, curcumin, nicotinamide, EGCG, and hydroxycitrate
  • supplemental resveratrol at 150 mg/day improved memory and cognition in humans

The author provides very specific anti-aging recommendations that could be followed by just about anyone. Read the book for details. Scientists are working feverishly to develop more effective anti-aging techniques. I look forward to a second edition of this book in three to five years.

Steve Parker, M.D.

PS: People with certain medical conditions, such as diabetics taking drugs that can cause hypoglycemia, should not do intermittent fasting without the blessing of their personal physician. If you have any question about your ability to fast safely, check with your doctor.

PPS: If you have diabetes or prediabetes and want to reduce your carbohydrate consumption, consider my Low-Carb Mediterranean Diet or Paleobetic Diet.

Are Low-Carb Diets Lethal?

Adult life is a battle against gravity. Eventually we all lose.

Adult life is a battle against gravity.

Japanese researchers say low-carb diets are causing premature death. I’m skeptical.

It’s a critically important issue because many folks with diabetes restrict their carbohydrate consumption to keep their blood sugars under control. Maybe it’s crazy, but they think they’ll live longer and have fewer diabetes complications if their glucose readings are under 200 mg/dl (11.1 mmol/l) most of the time.

The potentially healthful side effects linked to low-carb eating include reduced weight, higher HDL cholesterol, and lower triglycerides and blood pressure. The aforementioned Japanese investigators wondered if the improved cardiovascular risk factors seen with low-carb diets actually translate into less heart disease and death.

How Was the Study At Hand Done?

The best way to test long-term health effects of a low-carb diet (or any diet) is to do a randomized controlled trial. You take 20,000 healthy and very similar people—not rodents—and randomize half of them to follow a specific low-carb diet while the other half all eat a standard or control diet. Teach them how to eat, make damn sure they do it, and monitor their health for five, 10, or 20 years. This has never been, and never will be, done in humans. In the old days, we could do this study on inmates of insane asylums or prisons.

What we have instead are observational studies in which people voluntarily choose what they’re eating, and we assume they keep eating that way for five or 10+ years. You also assume that folks who choose low-carb diets are very similar to other people at the outset. You depend on regular people to accurately report what and how much they’re eating. You can then estimate how much of their diet is derived from carbohydrate and other macronutrients (protein and fat), then compare health outcomes of those who were in the top 10% of carb eaters with those in the bottom 10%. (We’ve made a lot of assumptions, perhaps too many.)

Of the observational studies the authors reviewed, the majority of the study participants were from the U.S. or Sweden. So any true conclusions may not apply to you if you’re not in those countries. In looking for articles, they found no randomized controlled trials.

The observational studies estimated carb consumption at the outset, but few ever re-checked to see if participants changed their diets. That alone is a problem. I don’t know about you, but I’ve had significant changes in my diet depending on when I was in college and med school, when I was a bachelor versus married, when my income was higher or lower, and when I had young children versus teenagers. But maybe that’s just me.

The researchers looked at all-cause mortality, deaths from cardiovascular disease, and incidence of cardiovascular disease. They don’t bother to define cardiovascular disease. I assume heart attack, strokes, and peripheral vascular disease. (But aren’t aneurysms, deep vein thrombosis, and pulmonary embolism vascular diseases, too?) Wouldn’t you think they’d carefully define their end-points? I would. Since they were going to all this trouble, why not look at cancer deaths, too?

What Did the Investigators Conclude?

Very low-carbohydrate dieters had a 30% higher risk of death from any cause (aka all-cause mortality) compared to very high-carb eaters. The risk of cardiovascular disease incidence or death were not linked with low-carb diets. Nor did they find protection against cardiovascular disease.

Finally, “Given the facts that low-carbohydrate diets are likely unsafe and that calorie restriction has been demonstrated to be effective in weight loss regardless of nutritional composition, it would be prudent not to recommend low-carbohydrate diets for the time being.”

If Low-Carb Dieters Die Prematurely, What Are They Dying From?

The top four causes of death in the U.S. in 2011, in order, are:

  1. heart attacks
  2. cancer
  3. chronic lower respiratory tract disease
  4. stroke

You’ll note that two of those are cardiovascular disease (heart attacks and stroke). So if low-carb diets promote premature death, it’s from cancer, chronic lung disease, or myriad other possibilities. Seventy-five percent of Americans die from one of the top 10 causes. Causes five through 10 are:

  • accidents
  • Alzheimer disease
  • diabetes
  • flu and pneumonia
  • kidney disease
  • suicide

Problem is, no one has ever linked low-carb diets to higher risk of death from any specific disease, whether or not in the top ten. Our researchers don’t mention that. That’s one reason I’m very skeptical about their conclusion. If you’re telling me low-carb diets cause premature death, tell me the cause of death.

Another major frustration of mine with this report is that they never specify how many carbohydrates are in this lethal low-carb diet. Is it 20 grams, 100, 150? The typical American eats 250-300 grams of carb a day. If you’re going to sound the alarm against low-carb diets, you need to specify the lowest safe daily carb intake.

For most of my career—like most physicians—I’ve been wary of low-carb diets causing cardiovascular disease. That’s because they can be relatively high in total fat and saturated fat. In 2009, however, I did my own review of the scientific literature and found little evidence of fats causing cardiovascular disease.

If you’re looking for a reason to avoid carbohydrate-restricted diets, you can cite this study and its finding of premature death. I’m not convinced. I’ll turn it around on you and note this study found no evidence that low-carb diets cause cardiovascular disease. The risk of cardiovascular disease had been the traditional reason for physicians to recommend against low-carb diets.

Steve Parker, M.D.

Reference: Noto, Hiroshi et al. Low-Carbohydrate diets and all-cause mortality: A systematic review and meta-analysis of observational studies. PLoS One, 2013; 8(1): e55050

This Just In! Obesity Reduces Lifespan

I'm worried about the kid's future health

I’m worried about the kid’s future health, too

MedPageToday has the details. A quote:

In a computer modeling study, very obese men lost just over 8 years of life compared with normal-weight men, and very obese women lost as many as 6 years, Steven Grover, PhD, of McGill University, and colleagues reported online in the Lancet Diabetes and Endocrinology.

They also found that very obese men and women (defined as a body mass index [BMI] of 35 and higher) lost about 19 years of healthy life, defined as living free of chronic disease such as diabetes and cardiovascular disease.

Note that “very obese” in this context has a specific definition: body mass index 35 or higher. Calculate yours.

The number of life years lost to obesity and disease were highest for those who were very obese in young adulthood and presumably stayed obese for years. In other words, becoming very obese at age 25 is more threatening than onset 60.

I first got interested in weight loss in the 1990s when I had an office-based primary care medical practice. It was obvious that many of the medical problems I was treating were related to years of obesity. Believe me, you’re much better off preventing those problems via diet and exercise.

Click for The Lancet study abstract.

Steve Parker, M.D.