Team McCallum

R&D for Lifetime of Life

Walking v diabetes+.

Dr Terry Dwyer and colleagues have found that walking cuts the risk of diabetes in a study of 600 adults in Tasmania. While the team focussed on diabetes, the results suggest a protective effect against metabolic syndrome and cardiovascular disease.

Roughly 600 adults aged around 50 in 2000 were tracked for 5 years.  At the start, most were overweight or obese and as a whole, the group gained weight over the period.

The volunteers were fitted with pedometers for 2 days in 2000. One finding was that those with higher daily step counts at this start time ended with a better body mass index (BMI), better waist to hip ratio and better insulin sensitivity, compared to those less active.

After 5 years, the group wore pedometers for another 2 days. As a whole, the group gained weight and became less active.  However, one third stayed active or increased their steps in the period, and again these were the ones with better measures on BMI, waist-hip ratio and insulin sensitivity.

The following figures are for those walking 10,000 steps, which is about 5 miles or 8km.

For a person of average height, weight dropped was just under 3kg, or about 6lbs. This corresponds to a BMI reduction of 0.83kg/metre squared. Insulin sensitivity increased by about 12%, with men doing slightly better than women.

These results are all ‘dose-dependent’. In other words, walking less still resulted in some improvements.

When the researchers factored in BMI, the differences between those active and those not disappeared, so the team attributed the improvement to a cut in body fat.

The researchers were looking at diabetes, and the improvement in insulin sensitivity would result in a considerably reduced risk of the disease.

The figures also strongly suggest there would be an improvement in other diseases linked to BMI and larger waists, including high blood pressure, metabolic syndrome, cardiovascular disease and more.

The impact on the waist is interesting, since fat stored around the waist is linked to adiposopathy (sick fat), and this study suggests that walking is a way to burn ‘sick’ fat preferentially to ‘healthy’ fat, reducing the waist to hip ratio.

January 17, 2011 Posted by | Accelerometer, Activity, Adiposopathy - sick fat, Aging, BMI - body mass index, CVD - cardiovascular disease, Diabetes, Exercise, High blood pressure, Metabolic syndrome, Success, Waist circumference, Walking, Weight management | Leave a comment

Udiet: the battlefield.

2010 was stuffed with debate over the reasons why people in developed countries are getting heavier.

 The most simplistic explanations focussed on overeating, or inactivity, or both. HFCS (high fructose corn syrup) also came in for a beating. The problem with this is that Europe imports very little HFCS, but countries in Europe are reporting more and more problems associated with obesity.

 www.obesitymyths.com comes up with a much larger range of interesting possibilities. But in 2005, the New York Times linked this site to sponsorship from fast food producers such as Coca-Cola and McDonald’s, in this article.

Two reputable groups of scientists published work where they found that the mantra of ‘eat less and exercise more’ doesn’t cover all of the potential reasons.

 A government group in the UK called Foresight was asked to predict what will happen there over time, based on best evidence, and building in realistic assumptions. In order to do so, they had to scour published research to identify the drivers of obesity and build a very detailed model of which drivers are most important. Written in simple English, this is probably the best explanation there is of the obesity epidemic.

The full report is available as a free PDF download here. However, at over 160 pages, it won’t be everyone’s cup of tea.

The second group of scientists published a summary of obesity drivers in November 2009. Again, this is available free using this link.

Their findings outline the battlefield for the Udiet.

1. Overeating, particularly re heavily marketed energy dense foods.

2. Underactivity, again with an organisation driver behind it.

3. Infection caused by bacteria and viruses.

4. Epigenetics, whereby prenatal and early postnatal exposure to the environment alters how genes are expressed without changing the genes. For example, babies born very underweight at birth who are incubated and fed rich diets to catch up weight have a higher risk of obesity and associated issues later in life.

5. Increasing maternal age. Animal studies have shown that babies born to older mothers are fatter than those born to younger mothers.

6. BMI breeding effect. Studies have found that those with a body mass index somewhat above average are producing slightly more children, on average, than the rest of the population, causing the population BMI to increase over time.

7. Assortitative mating is taking place. This hypothesis is that those with higher BMI prefer partners of similar kind, and due to the genetic effect, this leads to even heavier children. A wide range of population studies support this idea.

8. Sleep debt is happening, and leads to increased eating, increased fat deposition and lowered activity. Research shows metabolic changes occur to support this, and also leads to higher risk of diabetes and heart disease. For example, one study shows that getting one and a half hours less sleep than ideal over a two week period results in a diabetic-like profile for glucose and insulin.

9. Endocrine disruptors interfere with estrogen and androgen signalling, and have been building up in the human environment for some time.  These have been found to be involved in obesity in animals and in humans.

10. Commonly used medicines are known to contribute to weight gain. These include medicines for diabetes, high blood pressure, steroids, contraceptives, and anti-histamines.

11. Artificial ambient temperature. The hotter your environment, the less energy you burn keeping warm. The UK home went from 13 centigrade in 1970 to 18 centigrade by 2000. US homes went from 18 centigrade in 1923 to nearly 25 centigrade in 1986.

12. Mothers input. The state of the mother’s glucose and insulin handling systems directly affect the number of fat cells and the fat cell content of the baby.

13. Reduction in smoking rate. The scientists considered this so well documented they excluded it from their list.

14. Altered US demographics. A 2006 article along the same lines had found that alterations in the US population were increasing the races which tend toward higher BMI, therefore  increasing the average BMI of the nation.

The aim of the scientists’ report was not to remove the first two reasons from focus, but to show that the battlefield is considerably more complex than simply food and exercise.

These 14 points are not comprehensive. For example, other researchers have found that altering the circadian rhythm, by staying up late in artificial light and not synchronising your body clock to early morning light, is also a risk factor for weight gain. Also, breastfeeding v formula milk wasn’t mentioned, although formula milk is associated with higher risk of obesity.

January 9, 2011 Posted by | Activity, BMI - body mass index, Breastfeeding, Child Health, CVD - cardiovascular disease, Diabetes, Environment, Epigenetics, Exercise, HFCS - high-fructose corn syrup, High blood pressure, Obesity, Pregnancy, Pregnancy, Success, Thermogenesis, UK, United States, Weight management | Leave a comment

How smart is your dog?

John W Pilley and Alliston K Reid decided they would like to find out how much a dog can learn, given extensive training over a long period. The dog in question was a border collie called Chaser. Pilley and Reid couldn’t find Chaser’s limit after 3 years, when the dog could remember the names of over a thousand different objects and was still learning new ones.

The 1,022 objects were toys that Chaser used, each with a different name. However, Chaser also understood verbs, so the dog could combine the correct object with what was supposed to be done with that toy.

Further, Chaser understood a few groups. For example, there were objects that collectively could be referred to as balls, while others fell into the frisbee group.

Finally, Chaser could remember, at least for a short while, that a particular toy was excluded from the group to which it apparently belonged. For example, a particular ball was not to be counted as a ball. This remembering for a short time then forgetting is displayed by children when they learn.

As noted, Pilley and Reid did not find Chaser’s limit. They simply stopped trying to find it after the 3 years was up.

The other point of interest is that these things were toys to Chaser – fun, enjoyment, a real incentive to learn, and this be the main carry over message for humans.

But the next time you talk to your dog just be aware that the dog may understand more than you think.

January 9, 2011 Posted by | Activity, Brain, Exercise, Fun, Health, Language, Learning, Nature, Psychology, Success | Leave a comment

Eating well?

Two stories published today illustrate the difference between how well people think they eat and how well they really eat.

In Ecuador, Dr Simin Nikbin Meydani examined the diet and health of 350 men and women aged 65+ living in 3 poor neighbourhoods around the capital, Quito. Despite being poor, these people seemed to be eating well, with 33% of the men overweight and 55% of the women overweight.

In reality, their diet was heavily based on white rice, potatoes, sugar and white bread. Foods to provide micronutrients, such as chicken, legumes, fruit and vegetables, were sparse.

Using standard definitions, the team found that 19% of the men and 81% of the women had metabolic syndrome. High levels of C-reactive protein, a marker associated with cardiovascular disease risk, were found in 50% of the population. By analysing diet components, the team was able to tie risk of metabolic syndrome to under-consumption of vitamin C and vitamin E in this population.

The research was published in Public Health Nutrition.

Meanwhile, in the US, a survey of over 1,200 people found that many thought they were eating better than they really were.

53% thought their diet was somewhat healthy, 32% thought very healthy and 6% thought extremely healthy.

However, only 30% ate their 5 portions of fruit and vegetables a day, only half watched how many sweets they ate and 43% drank at least one can of sugar-sweetened beverage each day.

Of those who said they were at a healthy weight, 30% were clinically in the overweight range, and 35% were obese.

While 81% claimed to be active, the average amount of time spent moderately active was one hour, with a large chunk clocking up 5 hours per day sitting down.

The study was conducted by Consumer Reports.

January 4, 2011 Posted by | Activity, CVD - cardiovascular disease, Diet, Fruit, Gender, Health, Metabolic syndrome, Obesity, Soft drinks, Success, Sugar, United States, Vegetables, Vitamin C - ascorbic acid, Vitamin E, Weight management | Leave a comment

Long life and health.

In Feb 2010, our top story was that researchers in Australia had found that the body mass index (BMI) guidelines used for the general public are not the best ones for seniors. Later in the year, this article was cited by another one entitled “Survival of the Fattest”.

The BMI ranges used by the Australian team were 18.5 to 25 as normal, 25 to 30 as overweight, over 30 as obese, and under 18.5 as underweight.

The research published in the Journal of the American Geriatrics Society compared all-cause mortality, and cause specific mortality (cardiovascular disease, cancer, chronic respiratory disease) across the groups. Nearly 5,000 men and 5,000 women aged 70 to 75 at the start of the study were followed for a period of 10 years.

Compared to the normal weight group, those overweight had an 18% less risk of dying during the study. Even the obese group came in at the same risk as the normal weight people.

Another key finding was that being physically active made a large difference. Compared to an active lifestyle, men who were sedentary increased their risk of death by 28%, while inactive women more than doubled their risk.

The short meassage was fatten up a bit, but make sure you stay active. (Staying active is a theme we’ll return to in the rest of the year’s highlights).

This Australian research has already been cited by 5 other articles published in 2010.

In Sep 2010, 2 researchers wrote an article in the Journals of Gerontology Series A entitled ” Adaptive Senectitude: The Prolongevity Effects of Aging.”

This raised the question that some of the effects we normally think of as declines in old age, (including high blood pressure, metabolic syndrome, and obesity) may in fact be protective, while anti-oxidants and hormone supplements may be damaging. Or in other words, we don’t yet understand optimal aging.

Today, 29 Dec 2010, a group of scientists which appears to be related to those carrying out the February study has published in the Australasian Journal on Ageing, uder the title ” Are the national guidelines for health behaviour appropriate for older Australians? Evidence from the Men, Women and Ageing project”.

Here is their recipe for long life and health.

“Current BMI guidelines may be too narrow because BMI in the overweight range appears to be protective for both older men and women. Across all levels of BMI, even low levels of physical activity decrease mortality risk compared with being sedentary. Our findings suggest that consideration should be given to having different alcohol guidelines for older men and women and should include recommendations for alcohol-free days. The benefit of quitting smoking at any age is apparent for both women and men.”

December 29, 2010 Posted by | Activity, Aging, Alcohol, BMI - body mass index, Health, High blood pressure, Metabolic syndrome, Obesity, Smoking, Success, Weight management | Leave a comment

Vitamin D in high-risk seniors.

The International Osteoporosis Foundation (IOF) has responded to the recent publication by the Institute of Medicine (IOM) that recommended vitamin D levels. The IOF recommends levels 50% higher for high-risk seniors.

The IOF actually published its own finding for seniors in April 2010. In this, the IOF focussed on research into vitamin D in those aged 60 plus, relating to the impact on falls and fractures.

High-risk seniors are considered to be those in this age range who are also one or more of – obese, suffering from osteoporosis, limited in sun exposure (such as those in institutions or homebound), absorb vitamin D poorly, or are from populations suffering from low vitamin D levels, such as the Middle East and South East Asia.

The IOF recommends that blood levels of vitamin D are first established, then a formula used to calculate the supplements required, then blood levels are tested after 3 months for adequacy.

The IOF position paper showed that supplementation of vitamin D increased lower body strength in seniors and cut falls by 20%. There was also a cut of 20% in fractures. In both of these, supplementation below the amounts recommended by the IOF did not produce these benefits. The IOF did not recommend higher levels because no research has been carried out at higher levels.

The IOM recommends a blood level of 20 ng/ml (50 nmol/L). The IOF recommends a blood level of 30 ng/ml (75 nmol/L) for high-risk seniors as this is where the research found the benefits.

Supplementation at 10 micrograms/day (400 IU/day) produced no improvement. For this reason, the IOF recommended that high-risk seniors should take 800-1,000 IU/day, noting that this is well below the 4,000 IU/day toxic limit published by the IOM.

December 3, 2010 Posted by | Activity, Aging, Health, Obesity, Osteoporosis, Success, United States, Vitamin D | 1 Comment

Vitamin D v metabolic syndrome.

Researchers from the University of California Davis Medical Center found that patients with metabolic syndrome (but otherwise healthy) were much more likely to have insufficient vitamin D in their blood than controls without metabolic syndrome.  The patients came from around Sacramento, a part of northern California with plenty of sun, making the results more surprising.

Dr Ishwarlal Jialal and team compared 44 patients who had metabolic syndrome, but without diabetes or cardiovascular disease (CVD), against 37 healthy controls matched for age and gender.

The Institute of Medicine (IOM) has very recently published recommended levels of calcium and vitamin D, and based on best evidence, worked on a level of 20ng/ml of vitamin D in the blood as sufficient.

Dr Jialal found that 8% of controls had insufficient vitamin D at the IOM level, but in the metabolic syndrome group it was 30%.

The average value of vitamin D in blood in the metabolic syndrome group was found to be 23.1ng/ml, which suggests the IOM recommended level of 20 ng/ml may be too low. In the control group, it averaged 27.8ng/ml.

Dr Jialal also found there was no difference in levels in winter and summer, which reinforces the finding that in northern California, normal activity in sunlight is not enough to generate adequate vitamin D levels. This contrasts with southern California, where research has shown there in no difference in vitamin D between those with and without metabolic syndrome, while in Florida (even farther south) diabetics do not tend to have low vitamin D.

Sacramento is about 39 degrees north. As most of Europe is at or north of this, it would put most Europeans at risk, unless they are out in the sun more than this US sample, or getting it from food sources.

Metabolic syndrome is a risk factor for diabetes, CVD and stroke.

December 2, 2010 Posted by | Activity, CVD - cardiovascular disease, Diabetes, Health, IOM - Institute of Medcine, Metabolic syndrome, Stroke, Success, United States, Vitamin D | Leave a comment

Pay attention to be happy?

What’s the recipe for being happy? The media have recently reported that research shows when our minds wander we tend, on average, to be unhappy. So should we simply pay attention to improve our happiness? The same research shows the answer is most definitely not. And buried in the detail is what we should really do for more happiness.

According to Matthew A Killingsworth and Prof Daniel T Gilbert, both of Harvard University, as published in Science, “We developed a smartphone technology to sample people’s ongoing thoughts, feelings, and actions and found (i) that people are thinking about what is not happening almost as often as they are thinking about what is and (ii) found that doing so typically makes them unhappy.”

2,250 people took part. Their smart phone went off and they answered whether they were focussed, or if they weren’t, whether they were happy, neutral or sad. Plus they said what they were doing.

Just under half had minds-a-wandering when phoned. Out of 22 possible activity answers, 21 resulted in thinking of other things at least 30% of the time.

The only exception was sex. When people who were involved in sex were phoned – at least of those who actually answered the call – most were focussed on – sex.

Killingsworth and Gilbert concluded from another check they ran that mind wandering did indeed cause unhappiness, as we worked on more unhappy things than happy things. If so, it might make sense to pay attention to be happy, though the researchers recommended otherwise.

Here’s a quite different view that has been around for a while. It’s called creativity, or ‘flow‘. If you are being really inventive, really creative, having a much better time, or simply much more into the activity, what do you do when your smart phone goes off?

Perhaps you’ll just ignore it. Perhaps you’ll answer, and say you were really involved in what you were doing. After all, the activity that headed up this list was having sex. More people who reported having sex said their mind was on the job than for any other activity.

This research may show up something much simpler, and something much more important. Forget paying attention to scrape out a tiny little bit of extra happiness. Focus on sorting out the activities people were doing that caught their attention, and the ones where their minds wandered (to an even less happy place).

The 3 activities at the bottom the pile, where minds wandered the most, were resting, working, and using a home computer.

Out of the 22 activities surveyed, here are the top 3. Sex – exercise – having a chat.

Take your pick. It’s whatever you prefer most that will do you most good.

November 14, 2010 Posted by | Activity, Exercise, Health, Positive Psychology, Social networks, Success | Leave a comment

Yoga v walking for mood?

Dr Chris C Streeter of Boston University School of Medicine compared the effects of walking to yoga and the impact on mood in healthy people.

Previous research had shown that yoga increases a neurotransmitter, called GABA, in the brain. Increasing GABA is linked to less anxiety and depression, and cuts PTSD (post-traumatic stress disorder). Increasing levels of GABA is one approach used in medicines to treat these conditions.

The current study was designed to see if yoga’s known beneficial effects on mood were due to GABA effects, or simply due to exercising (which also improves mood, depression etc). So Dr Streeter tried to match the exercise content of walking with the exercise content of yoga, to see which would win.

Brain scans were used to check on activity in the thalamus. This is an area of the brain involved in mood, and it gets more active at higher levels of GABA.

This is where things went a bit different to what the research team thought would happen.

The yoga group showed a bigger improvement in mood than the walking group. And the yoga people appeared to show more activity in the thalamus, so more GABA. So far so good.

However, the number of people completing the study was small, and the improvement in GABA was not statistically significant. The groups also had a couple of key differences – the yoga group drank more alcohol, while the walking group exercised more when out of the yoga/walking comparison. Perhaps the walkers improved less because they were already getting lots of benefit from exercise.

Or could it be that the yoga group got certified instructors in lyengar yoga, while the walking group got to walk around the inside of gym for an hour per session?

The jury is out, but the research did turn up one key finding.

This study lasted 12 weeks and involved people new to yoga, and it produced about half the increase in GABA that previous studies with experienced practitioners had reported. So if you want to get the full mood benefits of yoga, you’re going to have to stick with it for a fair while.

November 13, 2010 Posted by | Activity, Anxiety, Brain, Depression, Exercise, PTSD, Success, Walking | Leave a comment

Sweet 16 tests cognitive decline.

The MMSE (mini mental-state exam) is a standard check used to determine whether cognitive decline has set in. It has a number of issues, such as the 10 to 15 minutes it takes to administer, the need for pen and paper, and the fact that it remains copyrighted, so there is a charge for use. Dr Tamara G Fong and colleagues developed the Sweet 16 to overcome these issues.

Then the team validated the test to prove that it is at least as accurate as the MMSE. The validation results are published in the Archives of Internal Medicine and on the web site of the developers, where you can also get the Sweet 16 test, how to administer it, how to score it, and which scores on the Sweet 16 correspond to scores used in the MMSE.

These validation results refer to the ‘sensitivity’ and ‘specificity’ of the Sweet 16 (and MMSE for comparison). Sensitivity means the rate at which it gets positives (those with the condition) correct, from 0 (none correct) to 1 (all positives correct). Specificity is the rate at which it gets negatives (those without the condition) correct, again from 0 to 1. The closer the test is to 1 on both sensitivity and specificity the better.

The Sweet 16 is free for non-profit use. It takes 2 to 3 minutes to ask the questions and score it. It doesn’t require that the patient uses a pen or paper. And the results were validated against results produced by specialised clinicians using live cases.

Perhaps best of all, it’s easy to use a few of these questions from time to time as a check on how your seniors are doing in this respect.

The developers point out that this is a gateway test, intended as a quick check to see if a specialist should be consulted.

Typically, an MMSE score of 25 or above (out of 30) is considered normal, and the MMSE <-> Sweet 16 paper shows this to be 14 or more out of 16 on the Sweet 16 test.

Click here for the Sweet 16 training manual, test, and comparison of MMSE/Sweet 16 scores.

November 9, 2010 Posted by | Activity, Brain, Cognitive decline, Health, Memory, MMSE cognitive test, Success, Sweet 16 cognitive test, Tamara G Fong | Leave a comment