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.

Advertisements

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

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

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

Preventing falls in older adults.

The US Preventive Services Task Force is reviewing its recommendations on primary care and preventing falls in the elderly. A team of scientists has analysed extensive research studies to conclude that vitamin D supplements and exercise are the top treatments.

The report in the Annals of Internal Medicine shows that the team evaluated nearly 3,500 published studies to identify good quality randomised control trials that related to primary care interventions for falls in elderly adults living in the community. Amongst other results, they ended up with 16 studies relating to exercise and 9 relating to vitamin D.

The exercise trials included gait, balance, or functional training, typically along with strength, resistance, or general exercise.

The exercise studies averaged a 13% reduction in the risk of falls, while the vitamin D trials averaged a 17% reduction.

Other approaches such as vision correction, medication assessment, home-hazard modification, and behavioral counseling weren’t found to be effective in reducing falls.

December 23, 2010 Posted by | Aging, Exercise, Health, Success, Vitamin D | Leave a comment

Vitamin D and women seniors.

A large study of elderly women in the US has found that there appears to be a u-shaped link between vitamin D and frailty and death. The optimal range was found to be 20 to 30 ng/ml, with poorer outcomes below and above this range.

Over 9,700 women aged 65+ had blood levels of vitamin D checked and their level of frailty tested.

To be considered frail, women has to have at least 3 of the following factors – recent bodyweight loss of at least 5% – grip strength in the lowest fifth of those tested – walking speed in the lowest fifth – self-reported lethargy – weekly walking duration in the lowest fifth.

Taking those in the 20 to 30 ng/ml group as the reference, those with 15 to 19.9 ng/ml appeared to be more likely to be frail, though this just failed to reach statistical significance. In those with under 15 ng/ml, the risk of being frail was 47% higher, while in those above 30 ng/ml, the risk was 32% higher. The researchers noted that this U-shaped relationship existed even if those taking supplements were removed from the calculation, so the result is not skewed by those taking supplements because they are frail.

Follow up checks were offered at 6 years (when 6,300 took part) and at 10 years, and the women were tracked for an average of 4.5 years.

Considering the 4,500 women who were not frail at the start, those in the under 20 ng/ml category appeared to be more likely to die or to become frail.  Again this failed by a small margin to be statistically significant, except for the under 15 ng/ml group, which was 40% more likely to die.

The research appears in the Journal of Clinical Endocrinology and Metabolism. In an editorial, independent researchers concluded that getting blood levels into the 20 to 30 ng/ml range appeared to be safe and efficaceous.

December 9, 2010 Posted by | Aging, Health, Success, Vitamin D | 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 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

Calcium and vitamin D by IOM.

The Institute of Medicine (IOM) was asked by US and Canadian health authorities to conduct an independent, evidence based review of the dietary requirements for calcium and vitamin D.

Overall, the committee concludes that the majority of Americans and Canadians are receiving adequate amounts of both calcium and vitamin D. Further, there is emerging evidence that too much of these nutrients may be harmful.”

Prof A Catherine Ross chaired the committee conducting this update, the first since 1997. The team reviewed over 1,000 studies on vitamin D and calcium and took further evidence from experts.

The review covered all health outcomes,  including cancer, cardiovascular disease, high blood pressure, diabetes, metabolic syndrome, falls, immune response, neuropsychological functioning, physical performance, preeclampsia, and reproductive outcomes. It found that only in relation to bone health are the results unequivocal, and based its recommendations on this.

The committee noted that studies appearing in the media re population levels of deficiency are using arbitrary levels that have not been established by a central authority, and so have little validity.

Based on available data, the committee found almost all individuals get sufficient vitamin D when their blood levels are at or above 20 nanograms per milliliter as it is measured in the US, or 50 nanomoles per liter as measured in Canada.

Also, the committee considered that few people are getting their vitamin D from sunlight, and based their recommendations on this.

A full breakdown of the recommendations by age range and gender is at the IOM short report on calcium and vitamin D. Please note a number of special situations are omitted from this but are covered by the full 678 page report, so check with your physician.

Some subgroups—particularly those who are older and living in institutions or who have dark skin pigmentation—may be at increased risk for getting too little vitamin D.

National surveys in both the United States and Canada indicate that most people receive enough calcium, with the exception of girls ages 9-18, who often do not take in enough calcium. In contrast, postmenopausal women taking supplements may be getting too much calcium.

Too much calcium is linked with kidney stones, while too much vitamin D is linked to kidney and other tissue damage. The short report therefore gives 3 values for each group – the estimated average amount (enough for the average person), the recommended dietary allowance (the level at which nearly everyone gets enough) and the upper level intake (the level at which more will cause harm rather than good).

In conclusion, “the committee emphasizes that, with a few exceptions, all North Americans are receiving enough calcium and vitamin D. Higher levels have not been shown to confer greater benefits, and in fact, they have been linked to other health problems, challenging the concept that “more is better.””

November 30, 2010 Posted by | Aging, Calcium, Canada, Cancer, Child Health, Cognitive decline, CVD - cardiovascular disease, Diabetes, Gender, High blood pressure, IOM - Institute of Medcine, Metabolic syndrome, Success, United States, Vitamin D | Leave a comment

Brain use v Alzheimer’s.

Dr Fergus IM Craik and two other researchers in Canada have found that life-long bilingualism delays the impact of Alzheimer’s by about 5 years.

211 patients who were diagnosed with probable Alzheimer’s were checked for factors known to delay the appearance of Alzheimer’s, such as educational status, plus fluency in one or more languages. In this sample in Canada, almost 50% were bilingual. The groups happened to be well matched for factors already known to make a difference, so any residual difference was linked to whether the patient was monolingual or bilingual.

On average, the bilingual patients were diagnosed 4.3 years after those speaking one language, and the onset of symptoms appeared just over 5 years later in bilingual versus monolingual speakers.

The doctors did not attribute this to Alzheimer’s actually starting later in bilingual speakers, but rather to a ‘cognitive reserve’, a greater store the disease had to work through before symptoms became evident.

Since educational attainment is a known instance where the symptoms of Alzheimer’s are delayed, the language factor is unlikely to be limited to languages. Rather, it appears to be a case of the more you use your brain (whether on languages or otherwise) the later in life you lose it if you are affected by Alzheimer’s.

The team reported a similar delay in 2007 when looking at the broader topic of dementia.

So the message for your brain is simple – use it or lose it.

November 21, 2010 Posted by | Aging, Alzheimer's, Brain, Cognitive decline, Dementia, Health, Success | Leave a comment