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

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

What did grandad eat?

First, there was genetics, which was going to tell us the whole story simply by sequencing our genes. However, when our genes got sequenced, the picture only got a little clearer.

Then there was epigenetics (epi means above, so epigenetics is above genetics). With epigenetics, your gene sequence does not change, but genes can be switch on or off (pretty much like lightbulbs) by events that happen. Things are getting more complex if you have to account for both the genes and the environment, and the picture is harder to read.

Now comes inherited epigenetics. This means information about the parents’ environment that is passed to offspring, even if the parent never sees the offspring alive (which cuts out passing this by the more simple route of learning). The genes aren’t altered in the child, but expression (whether on or off) is controlled by the environment of the child’s parent.

Various conditions in the mother’s environment appear to get passed on epigenetically, but in this type of study it is hard to rule out mechanisms such as shared environment while in the womb.

So scientists trying to unravel this puzzle are looking at situations where the parent involved is the father, and does nothing more than supply the sperm (with no other influence in the life of the mother or child).

Dr Oliver J Rando and team have been trying to make headway in this using mice. The father was fed a low-protein high-sugar diet, allowed to mate with a female on a standard diet, but with no other contact. Compared to controls (father on standard diet, mother on standard diet) it was found that the offspring had 1600 genes which expressed differently and 500 where the difference was major. This affected blood fat profiles and cholesterol production.

The team couldn’t say whether it was low protein that was important, or high sugar, or some other factor such as low micro-nutrients. And they couldn’t work out how, precisely, this information was passed on, since they couldn’t find a difference in the sperm of the mice.

Unless you are a scientist this is barely interesting. However, the authors point out that two studies have shown inherited epigenetics in the paternal line at work in humans – but it skips a generation.

To at least a certain extent, you are what your grandfather ate.

In 2002, a research team published “Cardiovascular and diabetes mortality determined by nutrition during parents’ and grandparents’ slow growth period”.

In 2006, another team published “Sex-specific male line transgenerational responses in humans”.

These show that a severely restricted diet at key points in your grandfather’s time increase your risk of obesity, diabetes and cardiovascular death, as you are pre-programmed by granddad’s famine-like environment.

December 29, 2010 Posted by | Cholesterol, CVD - cardiovascular disease, Diabetes, Diet, Epigenetics, Genetics, Health, Obesity, Success | Leave a comment

Oranges v supplements.

Is an orange just a source of vitamin C say, as per a supplement, or is there more going on?

Prof Tory L Parker and team established the components of a standard orange and the amounts of each found in whole fruit. The team then systematically checked each combination of these compound to see whether the effects were the same as whole orange, more beneficial or less beneficial.

Whenever we eat carbs and fat, we release free radicals that increase the risk of hardened arteries and heart disease. Eating fruit as a dessert protects us from this, as these contain anti-oxidants that mop up the free radicals for a few hours.

The question is – which combination of anti-oxidants works best? Can you just throw everything together and it works?

The anti-oxidants (individual phenolythic compound) in a navel orange are quercetin, hesperidin, luteolin, myricetin, p-coumaric acid, naringenin and chlorogenic acid.

By systematically checking the Oxygen Radical Absorbance Capacity (ORAC) for every possible mix, it was found that some had very high benefit, but one component actually reduced this. This means that while whole orange is good, it isn’t at the optimum.

The team found that hesperidin and naringenin were synergistic, giving an effective that is stronger than merely additive.

The university where the research was conducted has applied for patents on the results, in navel oranges and for similar work done on blueberries and strawberries. No doubt supplements with these mixes will be forthcoming.

In the meantime, remember you can get most of the benefits by ditching the sweet after a meal and eating an orange instead.

December 25, 2010 Posted by | CVD - cardiovascular disease, Diet, Fruit, Health, Success | 1 Comment

Eat yourself healthy.

First published in January 2010, here’s a list of food that not only tastes great, but also improves your health profile.

Almonds. Research just published in Dec 2010 show that these improve insulin resistance in those beginning to develop diabetes.

Apples (unpeeled) for quercetin. Located just under the skin of an apple, quercetin has been found to kill viruses directly. It also increases the level of sirtuin 1. Sirtuin 1 helps in the repair of damaged DNA, and is linked to improvements in type 2 diabetes, aging, and Alzheimer’s. It also appears to increase exercise capacity.

Baked beans for soluble fibre. This helps lower blood sugar levels and cholesterol. Research published in Jan 2010 found that higher blood sugar levels (irrespective of body mass index) are linked to an increased risk of cancer.

Chillies. Linked to an increase in calories burned as you break down food, lasting up to 2 hours after you eat them. Easy weight control!

Dark chocolate (or cocoa). Various studies published in 2010 found that eating just a couple of cubes of dark chocolate a day, or a cocoa at night, was linked to lower risk of heart attack and stroke.

Frozen peas for vitamins B and C. The B vitamins help the nervous system, the vitamin C helps cut the length of colds.

Green tea. Too many benefits to list! Research published in Jan 2010 found it cut the risk of lung cancer, in both smokers and non-smokers.

Oily fish for omega-3. Another one with too many benefits to list. In an area of the US known as the ‘stroke belt and buckle’, which has much higher rates of stroke than normal, Dec 2010 research linked this to low consumption of oily fish, and with high consumption of fried non-oily fish, which greatly increases uptake of omega-6, to the detriment of omega-3.

Grapefruit. Research in 2005 showed that eating fresh grapefruit before meal led to weight loss. Research published in 2010 tied this down to the active ingredient naringen. Check out all medications before using grapefruit because this potent chemical interferes with quite a wide range.

New potatoes. When new, these have a better glycemic profile, breaking down more slowly and providing a long acting, less peaked energy response than baked potatoes. And in December the head of the US potato marketing board finished a month of eating absolutely nothing but potatoes, to show that they get more criticism than they deserve.

Oats for beta glucan. This soluble fibre lowers ‘bad’ cholesterol.

Olives for monounsatured fat and phenolics. The list of research in 2010 on the benefits of olive oli on the cardivascular system goes on and on.

Parsley for chlorophyl. A good source of antioxidants, but chewing a little parsley after a meal mops up any unpleasant odours.

Poached or boiled eggs, but not fried, for lecithin. Research shows two eggs for breakfast will cut 400 calories from your overall intake during the day. If you are not interested in the weight loss angle, the lecithin gets converted into a neurotransmitter involved in good memory.

Pomegranate juice. A very small glass per day has been found to reverse artery damage caused by cholesterol.

Prunes for ferulic acid, which helps to keep your bowels regular.

Tomatoes. Another in the ‘too many benefits to list category’. As an example, eating tomato products is linked with a reduction in the risk of prostate cancer in men.

Wholewheat pasta. Another one that gives a long lasting energy source without pushing blood sugar levels through a dangerous peak. It has to be wholewheat!

Turmeric spice for curcumin. The active ingredient, curcumin, turned up ever so frequently in 2010, Protective against too many cancer types to list. Appears to protect the brain against the effects of stroke. Looks to have a neuro=protective effect in brain degeneration diseases, including MS, Alzheimer’s and more. Plus, it makes your rice look really nice!

December 25, 2010 Posted by | Aging, Alzheimer's, Cancer, Capsaicin - chillis, Chocolate, Cholesterol, Curcumin - turmeric, CVD - cardiovascular disease, Diabetes, Diet, Fibre, Fish, Fish oil, Glycemic index, Grapefruit, Green Tea, Health, Multiple sclerosis, Obesity, Olive oil, Omega-3, Omega-6, Parkinson's, Pomegranate, Stroke, Success, Vitamin C - ascorbic acid, Weight management, Whole grain | Leave a comment

Vitamin B1 v heart attacks.

A particular form of vitamin B1 called benfotiamine has been found to protect against heart attacks and aid recovery from heart attacks.

Vitamin B1 is also called thiamine and thiamin. It is water soluble. Benfotiamine is an analog of B1 (has the same action) but it is fat-soluble.

A team reported a study of heart attacks in mice with and without diabetes, in the Journal of Molecular and Cellular Cardiology. The aim was to find out whether a supplement of benfotiamine improved the chances of surviving a heart attack in diabetic mice. It turned out that the supplement improved the chance of survival of both diabetic and non-diabetic mice.

The mice study was backed up by a lab dish study of human heart cells. This showed that benfotiamine cut the risk of cell death when the cells were starved of oxygen, as happens in a heart attack.

There were other benefits, such as reduced diastolic blood pressure in diabetics before a heart attack, reduced blood pressure in both groups after a heart attack and growth of new blood vessels in the damaged area of the heart.

The levels at which the mice were supplemented, 70mg/kilo, is far in excess of the human bodies normal storage capacity for water soluble B1 – about 30mg – which may be why the researchers chose the fat-soluble version.

Benfotiamine is available as a supplement for humans, while good sources of vitamin B1 are Quorn (30mg/100g), pork, milk, cheese, eggs, peas, beans, fish, wholegrain pasta and wholegrain bread.

Deficiency is rare in the developed world – it leads to beriberi – but studies have found that benfotiamine helps prevent other complications of diabetes.

December 7, 2010 Posted by | CVD - cardiovascular disease, Diabetes, Fish, Health, High blood pressure, Success, Vitamin B1 - thiamine, Whole grain | Leave a comment

Aspirin v cancer and death.

Prof Peter M Rothwel and team found that a small aspirin a day cut for middle-aged people cut cancer rates significantly and also cut the overall risk of death by about 10%, according to a study published in the Lancet.

The team looked at 8 studies, each lasting 4 years or longer, involving over 25,000 people in total. They found that aspirin cut the risk of dying of cancer by 21%.

Different types of cancer returned quite different rates of risk reduction, and details of these are contained in the article in the Lancet. However, the greatest benefit was seen in gastrointestinal cancers.

Prof Rothwell explained that the mechanism of protection is thought to be that aspirin helps cells with damaged DNA to die as they should (called apoptosis) rather than replicating as cancer cells do.

The risk of a serious bleed event from aspirin was put at 1 event per thousand years of use, with only 5% of these being fatal, thus resulting in the overall cut in the risk of death. The best profile appears to be starting aspirin at around age 45 to 50 and discontinuing at age 75, when bleed events become more likely.

The benefit appears to build up slowly and only becomes statistically significant after about 5 years of use. The trials appear to show that the benefit increases the longer that aspirin is used, with 20 year trials showing better figures than shorter term ones.

While the study did not include enough women to determine results for breast cancer and ovarian cancer, the overall figures apply to both men and women. They also apply irrespective of smoking status. Benefit increased with age, in keeping with the time at which cancer normally starts to develop.

The team found that 75mg/day was the dose at which these benefits appeared, and that doses higher than this did not confer any additional gains.

The overall cut in death risk is in keeping with previous studies, which have found that aspirin cuts the risk of death from strokes and heart attacks.

December 7, 2010 Posted by | Aging, Aspirin, Breast cancer, Cancer, CVD - cardiovascular disease, Health, Peter M Rothwell, Stroke, Success | Leave a comment

Preventing Alzheimer’s?

Earlier in 2010 TeamMcCallum published research showing that beetroot juice lowered high blood pressure. The mechanism was that beetroot is rich in nitrate, bacteria on the tongue convert this to nitrite, which in turn gets converted to nitric oxide. The nitric oxide dilates blood vessels and so lowers blood pressure.

Now Dr Zvonimir S Katusic and team from the Mayo Clinic in Rochester, Minnesota, have researched the apparent risk link between cardiovascular disease (CVD) and Alzheimer’s. The study involved looking at the function of the lining of blood vessels (endothelium) in the brain.

First, the team inhibited the generation of nitric oxide by the vessels. This triggered a series of events that led to increased production of the amyloid precursor protein (APP), and an enzyme that normally cuts APP up so it can be disposed of. This increase in production/disposal led to an increase in the production of beta-amyloid plaque, one of the two major things seen in Alzheimer’s.

They checked the result in mice bred to be deficient in production of nitric oxide. These mice are insulin-resistant and have high blood pressure. The results were the same – more APP, more enzyme to chop it up, and more beta-amyloid plaque production.

According to one of the team “On the cardiovascular side we’ve known for some time that preservation of healthy endothelium is critical to prevent major cardiovascular events. Now it seems this may have important implications for cognitive impairment.”

Risk factors for CVD (high cholesterol, diabetes, high blood pressure, smoking, sedentary lifestyle and aging) have all been associated with inability of the endothelium to produce enough nitric oxide. Now they are linked by this research to Alzheimer’s.

This explains the protective effect of, say, exercise. And beetroot juice too!

December 4, 2010 Posted by | Aging, Alzheimer's, Cholesterol, Cognitive decline, CVD - cardiovascular disease, Exercise, High blood pressure, Obesity, Smoking, Success | 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