Brisk walk can strengthen heart

Brisk walk can strengthen heart

- -Saturday 15^th November, 2003

http://news.bbc.co.uk/2/hi/health/3260525.stm

A good brisk walk is enough to strengthen your heart, researchers have found.

Some experts believe that only strenuous activity has any beneficial effect.

But a study of obese adults found moderate exercise was enough to raise the heart beat to recommended levels.

The researchers, from the University of Massachusetts, Boston, reported their findings at a meeting of the American Heart Association.

Advisory groups recommend that exercise must push the heart rate up to at least 55% of its maximum to have any positive impact.

Many believe that vigorous exercise is the only way to do this - but the latest study suggests this is not necessarily true.

Rather than the old adage that there is "no pain, no gain", they believe that "if the pace feels right, it probably is".

Lead researcher Professor Kyle McInnis said: "A large segment of the population still believes exercise must be vigorous, demanding or involve more complicated activities than walking to adequately raise one's heart rate.

"This perception of 'no pain, no gain' can discourage people from starting to exercise at all."

Treadmill tests

The researchers studied 84 obese adults who were seeking professional advice on a safe level of exercise.

At the first visit, researchers measured heart rate and oxygen use, while the subjects walked on a treadmill with a gradually increasing steepness until they felt tired.

On a different day, the subjects walked one mile on the treadmill with instructions to maintain a "brisk but comfortable" pace.

Participants completed the walk in an average of 18.7 minutes, at an average speed of 3.2 miles per hour.

During the self-paced walk, all the participants achieved the recommended levels of exercise intensity, based on their previous heart rate measures.

Thirteen were at moderate intensity (55-69% of maximum heart rate), 58 at hard intensity (70-89%) and 13 at very hard intensity (90-100%).

Professor McInnis said: "Comparison with the treadmill tests showed that when participants self-selected a speed that was comfortable but brisk, their heart rate and level of exertion was in a safe range but high enough to improve their cardiovascular fitness.

"You really can get your heart rate up to the level that your doctor would recommend, and you don't have to jog or run to do it."

Forget the gym

Dr Kevin Channer, a consultant cardiologist at the Royal Hallamshire, told BBC News Online he was concerned that many people thought it was too tough to try to get fit.

"If you do nothing at all then your cardiovascular risk is higher than somebody who takes exercise, but if you are obsessive about exercise and run for 15 miles every day, then your risk starts to rise again," he said.

"Being healthy isn't difficult. People don't need to play sport or go to the gym, they simply need to get out of their cars and go for a walk."

Dr Hugo Crombie, of the Health Development Agency, said everybody should try to take a minimum of 30 minutes moderate activity on at least five days of the week.

He said: "Walking is excellent exercise - not only does it provide the sort of activity to benefit health but it does not need any special skills, equipment or access to a gym.

"The evidence shows that people can be encouraged to walk more and that this increase can be maintained over the years."

A British Heart Foundation cardiac nurse said: "Brisk, regular walking is the ideal way for people to get the exercise they need to benefit their health: it's free and easy for most people to fit into their daily life and can influence weight loss, blood pressure, diabetes and cholesterol levels.

"It also provides a cardiovascular workout without putting too much strain on the heart."

Statins - how safe & good are they

Dangers of Statin Drugs:

What You Haven’t Been Told About Popular Cholesterol-Lowering Medicines

14th June, 2004

- Sally Fallon & Mary G. Enig.

Mary G. Enig, PhD is an expert of international renown in the field of lipid biochemistry.

Read up from the following link and be well informed before
your take statin.

http://www.westonaprice.org/moderndiseases/statin.html


-----------------------------------

Statins

Thursday 1^st September, 2005, BBC Radio 4

Having an abnormal level of cholesterol in the blood is a proven cause of heart attack.
Cholesterol can be controlled by the use of Statins, drugs that reduce the risk of heart problems by about 30 per cent.

Unfortunately, they usually require long-term use, and they do have side effects including tummy upsets, muscle ache and liver problems.

In addition a recent study by Heart UK has found that up to 50% of patients on statins fail to reach their cholesterol lowering target. They have been called the "Forgotten Fifty". . . . . . . . .

(http://www.bbc.co.uk/radio4/science/checkup_20050901.shtml)

Gift of Life - Avoid Childhood Overweight

Dr. James O Hill

(University of Colorado Health Sciences Center, Center for Human Nutrition)

Excess Weight in Childhood Means Health Problems as an Adult

Posted on 10:33AM (EST) on 2007-12-31

A landmark study published in the New England Journal of Medicine shows clearly that excess weight in children leads to an increased risk of heart disease in adulthood. The study followed over 270,000 Danish children over time. Those who were overweight - even a few pounds overweight - at ages 7-13 years were much more likely to develop heart disease between the ages of 25 and 71 years of age.

The more overweight the child, the more likely they were to develop heart disease. The risk remained even if the child later lost the excess weight.

This study provides clear evidence that childhood overweight leads to serious adult health problems. This is a wake up call for parents to be concerned about the weights of their children. The best solution is to ensure that your children achieve a health lifestyle and learn the importance of

good nutrition and regular physical activity.

Given that childhood obesity has tripled over the past three decades, how can we expect anything less than a major increase in heart disease in the future?

If your children are normal weight, help them stay there. If they are overweight, see your pediatrician to develop a plan for addressing their weight. Don't wait until they are adults with serious health problems. If you are thinking about New Year resolutions, how about a resolution to improve your family's lifestyle?

Thin People May be Fat on the Inside

Thin People May be Fat on the Inside

Every now and then a story comes along in the media that really supports my belief about the importance of physical activity for overall health. Research from London has used very sophistical imaging techniques to look at where people store body fat.

They report that people who use food restriction (ie. dieting) alone to lose weight may be at a lower weight than before but they appear to still have too much fat, particularly too much fat around their internal organs.

We know that fat around the internal organs is particularly bad and increases the chances of developing chronic diseases such as type 2 diabetes and heart disease.

This work suggests that you can use diet to lose weight but unless you also increase physical activity, you may be thin on the outside and fat on the inside. You may not be as healthy as you think.

This issue of fitness and fatness is vigorously debated in the scientific literature. Some people, such as my friend Dr. Steve Blair, at the University of South Carolina, argues that

many people who are overweight and physically active may be healthier than others who are at a lower body weight but sedentary.

The point here is that weight is important but so is diet and physical activity. Your genes help determine your body weight. You may be someone who is genetically prone to be thin or someone who is genetically prone to be overweight. If you are genetically prone to be overweight or obese, it may be very hard for you to ever be thin. What you can do, however, is to be at the healthiest weight you can be given your genetics. I believe that for most of us, our genes permit us to be at a healthy weight. This may require more work for some people than others.

The bottom line is that the scale is important but it is not sufficient. If you are at a healthy weight, make sure you are also eating a good diet and getting regular physical activity. Most people who are overweight or obese would improve their health by losing some weight. To maximize the improvement in health, pay attention not just to your weight but also to your lifestyle. Achieving a lower weight is good but achieving a lower weight and an active lifestyle is even better. This shows that just looking at someone’s outside is not enough to know if they are really healthy on the inside.

Tuesday, January 22, 2008

How Excess Fat Tissue Slowly Destroys You

The weight of research into the biomechanisms of fat tissue continues to grow. It just isn't sensible to be overweight - at least if long-term health and longevity happen to be on your list of goals. Here's the latest update on one of the ways in which excess fat tissue slowly destroys you from the inside: a team of University of Michigan Cardiovascular Center scientists reports direct evidence of a link between inflammation around the cells of visceral fat deposits, and the artery-hardening process of atherosclerosis. ... The discovery came partly by chance. He and his colleagues had been studying mice that lack the gene for leptin, a hormone generated by fat cells that plays a role in appetite and metabolism as well as reproduction. In an effort to get these obese mice to produce some leptin, the team developed a technique to transplant clusters of fat cells from normal mice of the same strain, into the leptin-deficient mice. The result surprised them. “In addition to producing leptin and preventing obesity, the fat transplants became inflamed, attracting immune cells called macrophages” Eitzman explains. “Since the mice were genetically identical except for leptin, this shouldn’t have happened. But the inflammation was there, and it was chronic.” The inflammation occurred around individual fat cells, or adipocytes. Further tests showed it was regulated by the same factors that regulate the inflammation that other researchers have seen in the naturally occurring fat deposits of obese mice - specifically a chemokine called MCP-1. But because the fat was transplanted, the inflammation could be attributed directly to the fat, and not to overfeeding of the mice, or the metabolic problems that overfeeding and obesity bring, such as diabetes. Armed with this discovery, the researchers set out to see what was causing inflammation to occur, and what implications it had.... “There appeared to be an interaction between the macrophages causing the inflammation in the visceral fat, and the process of atherosclerosis,” says Eitzman, who notes that blood vessels far from the site of the fat transplant developed increased atherosclerosis. All that excess fat hanging around over the years generates atherosclerosis, which then kills you: Most commonly, soft plaque suddenly ruptures, [causing] the formation of a thrombus that will rapidly slow or stop blood flow, that is, within 5 minutes, leading to death of the tissues fed by the artery. This catastrophic event is called an infarction. One of the most common recognized scenarios is called coronary thrombosis of a coronary artery, causing myocardial infarction (a heart attack). Another common scenario in very advanced disease is claudication from insufficient blood supply to the legs, typically due to a combination of both stenosis and aneurysmal segments narrowed with clots. Since atherosclerosis is a body-wide process, similar events occur also in the arteries to the brain, intestines, kidneys, legs, etc. ... According to United States data for the year 2004, for about 65% of men and 47% of women, the first symptom of atherosclerotic cardiovascular disease is heart attack or sudden cardiac death (death within one hour of onset of the symptom). This is one of the many reasons why people who keep in shape and stick to the health basics tend to live longer, healthier lives.

Overweight? You might not know it.

Overweight? You might not know it.

Medical Research Council, United Kingdom

11th December 2006

People who look slim and fit may not be as healthy as they appear. New research reveals that many people carry an unhealthy cushion of fat around their internal organs. As part of his research into type 2 diabetes, Professor Jimmy Bell of the MRC’s Clinical Sciences Centre at Hammersmith Hospital used magnetic resonance imaging (MRI) to scan more than 300 people to determine how and where the body stores fat.

MRI scan of a slim male, the green colouring shows external fat, the yellow highlights fat deposited around internal organs.

Professor Bell’s team discovered that potentially dangerous fat is often deposited around internal organs. The result is that the carriers appear healthy because they are slim.

The MRI scans suggest that up to 40% of the population could be carrying fat around and even in organs such as the liver, gut, heart and pancreas. Disused muscle may also be streaked with hidden fat that could provoke serious conditions like diabetes and heart disease in later life because the fat has a detrimental effect on chemical functions such as how energy is released from food.

Professor Jimmy Bell warns that looking good is not enough to stay healthy:

"The important message is people shouldn't be happy just because they look thin, it's not about looking fit or looking thin, it is about being healthy. You can look healthy but have a lot of fat internally which can have a detrimental effect. When you exercise you tend to burn the internal fat. Lifestyle changes have to include physical activity, it’s not enough simply to diet."

In fact, evidence suggests that yo-yo dieting could force the body to lay down fat around vital organs.

Professor Bell’s discovery challenges the assumption that a thin body is healthy by virtue of having little external fat. Instead he has shown that some underweight or slim people could actually be storing fat in a dangerous way.

Professor Bell continues:

“Traditional ways of measuring body fat such as Body Mass Index (BMI) give people the wrong idea of how much fat they have as it says nothing about internal storage. People have become obsessed with dieting but doing this without exercise means they may be putting fat in the wrong places.’’

“Through our research we are developing a full understanding of how genetic and environmental factors determine how much fat we deposit and where we put it. In the future we hope to use this information to change people’s lifestyles without going to the extremes of giving people drugs or operating on them.”

Video clip on cancer and obesity

** Obesity may increase cancers **
Soaring obesity levels could result in up to
12,000 cases of weight-related cancer
annually in the UK by 2010, say experts.

< http://www.bbc.co.uk/mediaselector/check/player/nol/newsid_6200000/newsid_6208600?redirect=6208690.stm&news=1&bbram=1&bbwm=1&nbram=1&nbwm=1 >

Importance of waist line and waist/hip ratio . . .

Measuring of the waist size at the level
of the navel when the abdomen is at
relaxed state gives a better indication
of whether there is too much fat around
the abdomen.
















To stay in low risk category:
The waist / hip ratio for female is to be
less than 0.8.

The waist / hip ratio for male is to be
less than 1.0.

Body Mass Index - a rough guide on over/under-weight

Avoiding cancer - Be Slim

Mediteranean diet 'cuts baby asthma risk'

Mediterranean diet

'cuts baby asthma risk'

Pregnant women who eat a Mediterranean diet may help protect their children from asthma and other allergies, researchers say.

The Crete team studied 468 mothers and their children from pregnancy to six and a half years after the birth.

They found asthma and allergies were significantly less common in children whose mothers ate lots of vegetables, fruit, nuts and fish during pregnancy.

The Thorax study also found eating high levels of red meat increased the risk.

It made that conclusion in cases where red meat was being eaten more than three to four times a week.

More than five million people in the UK have asthma, and one in 10 children is affected.

Previous work by the same team, from the University of Crete, found that children who ate a Mediterranean diet appeared to be protected from asthma and allergies.

The latest study suggests that the protective effect of the diet may kick in an even earlier stage.

The researchers found that by the time the children were six-and-a-half years old their diet appeared to have little impact on their risk of asthma and allergy.

However, their mother's diet during pregnancy appeared to be much more important.

This is of particular significance to mothers in the UK as we have one of the highest rates of childhood asthma worldwide - Leanne Male, Asthma UK

Beneficial nutrients

Consumption of vegetables more than eight times a week, of fish more than three times a week, and of legumes more than once a week, seemed to be particularly protective.

The researchers said the Mediterranean diet tended to be well balanced and full of foods which contained beneficial vitamins and minerals.

In particular, the diet was high in antioxidants, which help to keep tissues - including those in the lungs - healthy.

Fatty acids from fish were known to help cut potentially damaging inflammation.

The Thorax study continues: "Further studies are needed to better understand the mechanisms of this protective effect and the most relevant window of exposure."

Leanne Male, assistant director of Research at the charity Asthma UK, said: "This supports our advice to pregnant mothers to eat a healthy, balanced diet.

Obesity ' fuels cancer in women '

BBC NEWS - http://news.bbc.co.uk
Last Updated: Wednesday, 7 November 2007, 01:02 GMT

Obesity ' fuels cancer in women ' About 6,000 middle-aged or older women in the UK develop cancer each year because they are obese or overweight, a Cancer Research UK-funded study says. The study, which looked at 45,000 cases of cancer in 1m women over seven years, says this is about 5% of such cases. It is published online by the British Medical Journal and blames excess fat for 50% of cases of womb cancer and a type of oesophageal cancer. Last week an international study warned of the link between cancer and weight. CANCERS LINKED TO OBESITY Womb Oesophagus Bowel Kidney Leukaemia Breast Multiple myeloma (bone marrow) Pancreatic Non-Hodgkin's lymphoma Ovarian 'Bigger impact' The World Cancer Research Fund warned that carrying excess weight significantly increased the risk of cancer. Figures indicate that about 23% of all women in England are obese and 34% are overweight. The latest study looked at how often cancers occurred in 1.2m UK women aged 50 to 64 over a seven year period. More than 45,000 cases of cancer and 17,000 cancer deaths occurred during that time. Lead researcher Dr Gillian Reeves, from Oxford University, said: "We estimate that being overweight or obese accounts for around 6,000 out of a total 120,000 new cases of cancer each year among middle-aged and older women in the UK. "Our research also shows that being overweight has a much bigger impact on the risk of some cancers than others. "Two thirds of the additional 6,000 cancers each year due to overweight or obesity would be cancers of the womb or breast." Age difference The research found that the link between weight and risk ofcancer depended on a woman's stage of life. Invest in a healthier lifestyle today and we can reap the benefits of reduced disease risk and longer life tomorrow - Dr Ian Campbell - Weight Concern For example, being overweight increases the risk of breast cancer only after the menopause and the risk of bowel cancer only before the menopause. Sara Hiom, from Cancer Research UK, said: "This research adds to the evidence regarding the impact of being overweight or obese on developing cancer and dying from the disease. "While most people readily associate carrying extra weight with being a general health risk, many do not make a specific link with cancer." Dr Ian Campbell, medical director of the charity Weight Concern, said: "Whereas it was once thought there was little one could do to prevent cancer, it's now clear that lifestyle impacts greatly on overall cancer risk. "The message is clear. Invest in a healthier lifestyle today and we can reap the benefits of reduced disease risk and longer life tomorrow."

Visceral Fat - Fat surrounding organs - silent killers

What is Visceral Fat?

- health wellness

Visceral fat is different from other body fat. Visceral fat, also called intra-abdominal fat, refers to the fat that surrounds the internal organs. Subcutaneous fat, on the other hand, is body fat that is close to the skin's surface and is considered less dangerous, and easier to lose, than visceral fat.

Studies have shown that those with visceral fat are more susceptible to heart disease, stroke, diabetes and hypertension. Sedentary people, smokers and drinkers have been shown to have more intra-abdominal fat, or visceral fat, than active people who are non-smokers and non-drinkers. Stress may also be a factor in the storage of visceral fat on the body.

Visceral fat is harder to lose than subcutaneous fat because it is more deeply embedded in the body's tissues.

Visceral fat is only measured accurately by an imaging machine that can see how much of the abdomen is made up of visceral fat. (*) A person may be within a healthy weight range, but still have too much intra-abdominal fat around the internal organs.

The liver metabolizes visceral fat and releases it into the bloodstream as cholesterol. Harmful, or "bad" cholesterol, which is Low-Density Lipoprotein (LDL), builds up into a plaque that blocks the arteries. Losing weight through proper diet and effective exercise can help reduce visceral fat. How much fat a person eats does matter as studies have shown that those who eat 30% or more of their diets as fat usually have high amounts of visceral fat.

Walking is considered by many health and fitness experts to be a much better way of helping to control visceral fat than by doing exercises such as swimming where gravity keeps the body afloat. Walking at a fairly fast pace for a half an hour six days a week has been shown to help reduce visceral fat, while walking only three days a week has not been shown to have much affect on the reduction of visceral fat. However, doing no exercise at all has shown to increase the amount of visceral fat in the body.

* - Now portable body composition scanners are available which can give fairly good indication of visceral fat, etc. Such scanners are easy to operate and very cost effective.
(Ask for a free body composition scan - KL / Klang Valley areas only. HP:+6012-221 4122, cktan22@gmail.com)

Reversing Metabolic Disorder - Syndrome X

Sunday April 27, 2008 – the Star

Reversing the metabolic syndrome

BY LIM WEY WEN

Losing weight can be effortless if you overcome your insulin resistance, says expert.

Syndrome X. The Metabolic Syndrome. The Insulin Resistance Syndrome.

They may be different names, but all three point to the same set of health concerns affecting both the developed and developing world – expanding waistlines along with high blood pressure, cholesterol levels and raised blood sugar levels.

The Metabolic Syndrome, which increases the chances of people developing type 2 diabetes and dying from heart attacks, is now considered to be the driving force for a new cardiovascular disease epidemic, says the International Diabetes Federation.

“Eventually, after (years of) inactivity, poor diet and unhealthy lifestyle, people eventually tip over to develop the Metabolic Syndrome, which is really, the insulin resistant syndrome,” said Dr Ray Strand, author of the book Preventing Diabetes and Healthy for Life, while he was in Kuala Lumpur recently.

But, Dr Strand says that you can reverse the insulin resistant syndrome by applying a triad of healthy practises – eating a low glycaemic diet, increase moderate exercise and supplementing your diet with nutrition that helps insulin sensitivity – and lose weight without even trying.

Insulin resistance, the glycaemic index (GI) and the metabolic syndrome

When we eat or drink food that contains sugar (from simple sugars to complex carbohydrates) it breaks down to its basic units, glucose.

Family physician and author Dr Ray Strand ... You can reverse insulin resistance by applying a triad of healthy practises – eating a low glycaemic diet, increasing moderate exercise and supplementing your diet with nutrition that helps improve insulin sensitivity

Our body produces insulin (a hormone) to help muscle and liver cells absorb glucose from our blood to be used to produce energy or form energy stores.

However, when we consume food with high levels of sugar, our blood sugar levels rise rapidly and our body compensates by producing more insulin to bring the blood sugar levels down.

Soon, our cells may develop a resistance to insulin, and more insulin is needed for the cells to bring glucose from the bloodstream into our cells to maintain the blood sugar levels at a certain range.

So, if our body can produce enough insulin to counter insulin resistance (which prevents cells from taking in glucose), our blood sugar levels will remain the same.

It is when our insulin production drops, and insulin resistance stays the same; our blood sugar levels will increase, says Dr Strand.

But not all foods that contain sugar and carbohydrate have the same effect on our blood sugar levels. Some of these foods break down gradually (low glycaemic index) while some break down rapidly (high glycaemic index) during digestion to release glucose into the bloodstream, raising blood sugar levels at varying speed.

Dr David Jenkins, who was credited for the development of the glycaemic index, found in his first study in 1981 that “great differences (of GI) were seen not only between but also within most of the food groups, e.g. among cereals, the GI for wholemeal bread was 72% while for wholemeal spaghetti, it was 42%”.

That means if you eat wholemeal bread, your blood sugar levels will raise to a higher level over two hours as compared to wholemeal spaghetti.

The problem with spiking (rapidly raising) your blood sugar levels by eating high glycaemic foods is you over-stimulate the production of insulin, which subsequently cause blood sugar levels to drop below the normal range, says Dr Strand.

The low blood sugar levels will in turn, stimulate the release of stress hormones – cortisol and adrenaline – that causes hunger or craving for food, he added.

“So, what we’ve been calling emotional eating all this while is actually a natural response of the body,” he explained.

In the Metabolic Syndrome, insulin resistance raises blood sugar levels and the excess glucose is diverted into storage in the form of fat, says Dr Strand.

Reversing the Metabolic Syndrome

After years of studying medical literature and conducting clinical studies on the syndrome, Dr Strand, a family physician who specialises in nutritional medicine, could recite research statistics from memory if you asked him about his findings.

But, he got a shock when he found out that nine to 10% of adult Malaysians have developed diabetes.

“We have a worldwide problem, and its not just in the US and Canada, but also in New Zealand and Australia,” says Dr Strand.

And the metabolic syndrome (that increases the risk of diabetes) is said to affect 25% of the US and Canadian adult population, according to the Journal of American Medical Association, he said.

Despite extensive publicity and research, doctors are also diagnosing the disease (diabetes) too late, he added.

He said that according to a diabetologist in the US, more than 60% of the people whom physicians diagnose with diabetes already had some form of cardiovascular disease and 80% of them may die prematurely of a cardiovascular event.

You can’t lose weight if you have underlying insulin resistance, Dr Strand says.

“They (people with insulin resistance) hold on to fat like a sponge holds on to water. It’s an abnormal metabolic state where calories are no longer a culprit because the muscles can’t utilise the calories normally,” says Dr Strand.

“In my medical practise, I started to think: since the problem (in the metabolic syndrome and diabetes) is insulin resistance – which means that we are not as sensitive to our insulin as we once were – we need to make lifestyle changes to improve insulin sensitivity. It is just common sense,” said Dr Strand.

Improving insulin sensitivity

To find out how insulin sensitivity can be improved, Dr Strand referred to medical literature for answers.

And what he found was research showing that when people don’t make their blood sugar levels rise suddenly (by eating food with high GI), their body responds by secreting less insulin hormones (fat storage hormone) and more glucagon hormones (fat releasing hormones).

“This improves insulin sensitivity from a certain type of mechanism,” he said.

And that is not the only way to do it. Exercise can also do the trick, albeit a different way, Dr Strand says.

“A modest aerobic activity will improve your insulin sensitivity, but not weight resistance training,” he said.

So if you go for a 30-minute brisk walk or do an equivalent of aerobic activity five days a week, you would significantly improve your insulin sensitivity, he added.

Also, research has shown that supplementing some nutrients at an advanced level (more than the Recommended Dietary Allowance) also increases insulin sensitivity through yet another mechanism, says Dr Strand.

And so, in the year 2005, Dr Strand and his partners decided to put a combination of these three approaches to test in a pilot study on 25 people (five men, 20 women) who were at risk to develop full-blown Metabolic Syndrome.

By putting participants through a 12-week lifestyle modification programme involving low-glycaemic functional foods (meal replacements), a low glycaemic diet, and modest exercise, they wanted to see if the programme could reverse some of the symptoms of Metabolic Syndrome in affected people.

On average, the participants lost about 6% of their initial body weight, their BMI and waist circumference declined and other parameters of the metabolic syndrome improved.

Blood pressure, for example, declined from a baseline average of 131/86mmHg to 121/80mmHg (normal blood pressure is 120/80mmHg). Average total cholesterol, low-density lipoprotein (LDL) cholesterol and fasting blood sugars also dropped after 12 weeks on the programme.

The study concluded that these changes are consistent with a reversal of the Metabolic Syndrome with significant improvements in cardiovascular and metabolic health, says Dr Strand.

A subsequent study done at the University of Colorado on 60 people revealed similar results, he added.

Another study done by a doctor who gave a group of 12-year-old boys a low glycaemic breakfast or lunch and another group a high glycaemic equivalent found out that the group who ate high-glycaemic breakfasts or lunches ate about 80% more calories compared to their counterparts who ate low glycaemic meals. And similar results were also found when the doctor switched the groups, said Dr Strand.

Not ‘no carbs’, but take ‘good carbs'

Is it difficult to sell the idea of a low glycaemic diet to Asia where carbohydrate is staple?

“Yes it is. But it is difficult in the US, too,” Dr Strand said.

“All of our grains are processed and high glycaemic, and we (in the US) have the same problem as yours.” That is why it is about food choices we make rather than abstinence or cutting out carbohydrates, says Dr Strand.

It is like saying: “I’m going to take this bread and this rice (that is low glycaemic) rather than this (high glycaemic),” he added.

For Dr Strand, anything with a GI of over 60 is considered high and those with a GI between 40 and 60 is considered moderate.

Describing his experience in encouraging his patients to go on a low glycaemic diet, Dr Strand says, “(In the end), my patients come back to me and say ‘what is so hard about never getting hungry, feeling good, having more energy, more focus, seeing health parameters improve and losing weight without even trying?’”

For information about the glycaemic index of foods, please visit the University of Sydney School of Molecular and Microbial Biosciences Human Nutrition Unit database at www.glycemicindex.com.

What is Obesity?

(Ref: March 2004 issue of the Medical Journal of Malaysia, Volume 59, Issue No. 1)

U Shashikiran, V Sudha, B Jayaprakash, Department of Medicine, Melaka-Manipal Medical College, Jalan Batu Hampar, Bukit Baru, 75150 Melaka

Introduction

Obesity is a complex multifactorial chronic disease that develops from an interaction of genotype and the environment. Our understanding of how and why obesity develops is incomplete, but involves the integration of social, behavioural, cultural, physiological, metabolic and genetic factors.

In recent years, there has been a dramatic increase in the prevalence of obesity in Asia as well as in other regions of the world. Coincident with the high rates of obesity, the prevalence of other chronic diseases like type 2 diabetes mellitus, hypertension and coronary heart disease is also escalating, and this increase is expected to continue.

Measurement of Total Body Fat

A number of weight-for-height indices have been developed for measurement of body fat content of which the Body Mass Index (BMI) (defined as weight/height² [kg/m²]) is the most widely used. BMI generally correlated highly with adiposity, although it can sometimes misclassify total body fat content. For example, athletes who are muscular have a high BMI, due to muscle weighing more than fat, and will have BMI within the overweight range, even though they are not obese. The shortest and tallest subjects also tend to be misclassified as obese. It is possible to measure adipose tissue mass by various means, but most of these require sophisticated apparatus and techniques beyond the scope of most clinical practices. Although bio-electrical impedance (BIA) is easily applied, this technique requires further evaluation for its reproducibility in clinical and epidemiological population-based studies. Therefore, BMI, which is easy to calculate has been recommended as the measure of obesity for adults to be used in all studies.

Most studies that examine the risk of adverse health associated with obesity in Asian countries have been based on data from Europe or the United States. However, the increased health risks associated with obesity occur in people with lower BMI in the Asia-Pacific region when the standard criteria are used. Body fat in certain Asian ethnic groups was under-predicted by BMI when an equation derived from a Caucasian population was used. BMI / % body fat (% BF) ratios were also different among the Asian ethnic sub-groups. It has been recognized that the current WHO criteria to classify overweight and obesity in adult Europids using the BMI or waist circumference may not be appropriate in Asian or Pacific Island populations. There are many indications that in Asians, the risk of diabetes and other chronic diseases starts to increase rapidly when BMI or waist circumference are well within the accepted range for Europeans; therefore cut-off points recommended for white European populations will not help to identify Asian individuals at high risk.

The World Health Organization consultation on obesity proposed a system of classification based on BMI (Table I), similar to classifications used in a number of past studies on Europids. In these studies, the ranges for BMI (underweight, normal, overweight, obese) have been based on mortality outcomes where the confounding influences of cigarette smoking and co-existing chronic disease have been minimized. An individual with a BMI of 30 or more is considered obese. This applies to both men and women. For comparison, this would related to a direct measure of approximately 25% body fat in men and 30% body fat in women.

New Proposal

The steering committee of the Asia-Pacific perspective for redefining obesity, co-sponsored by the WHO Regional Officer for the Western Pacific (WPRO), the International Association for the Study of Obesity and the International Obesity Task Force has recommended different ranges for the Asia-Pacific region based on risk factors and morbidities (Table II). In Asians, the cut-offs for overweight (23.0 kg/m²) and obesity (25.0 kg/m²) are lower than the WHO criteria.

These are provisional recommendations which need to be revised in the light of further validation of studies and clinical experience. Some support for these cut-offs has come from data on Chinese living in Hong Kong where the morbidity risk increases with a BMI > 23 kg/m². Similar data have been published from the Chinese in Singapore. Hong Kong Chinese populations have a higher % BF for a given BMI which would partly explain why the health risks associated with obesity occur at a lower BMI. These results support the recommendations of using lower BMI cut-offs to define obesity in the Asia region.

In a study of North Indian population too, it was found that the conventional cut-off level of the BMI underestimates overweight and obesity when % BF is used as the standard to define overweight.

Distribution of Body Fat

In a study of the subjects with a BMI below 30 (not obese according to conventional BMI), about one-third of the men and almost one-half of the women were obese according to their measured levels of body fat. Some individuals who were found to be obese, judging by % BF had a BMI as low as 20. The conclusion is that BMI assessment produces significant numbers of false negatives - seemingly non-obese individuals by BMI who nevertheless qualify as obese by % BF.

It is not just the amount of fat but also its distribution that determines the risk associated with obesity. Abdominal or visceral fat is associated with the cardiovascular risk factors of the metabolic syndrome. The presence of excess fat in the abdomen out of proportion to total body fat is an independent predictor of risk factors and morbidity. In a study of Dutch men and women, the following waist measurements of > 102 cm in men or > 88 cm in women were found to be associated with a substantially increased risk of metabolic complications. Although the recent WHO report suggests that 94 cm in men and 80 cm in women should be the appropriate measures in Europids, these cut-offs are also not suitable for Asian populations as it has been observed that South Asians have high levels of abdominal obesity, although they may not be considered obese by conventional BMI criteria.

New Proposal

However, the steering committee of the Asia-Pacific perspective for redefining obesity has suggested different levels for defining abdominal obesity in Asians and proposed interpretation of waist circumference in the light of BMI also (Table III).

When using circumference measurements, it is important that standard anatomical locations are used. The WHO recommended methods are as follows. For waist or abdominal circumference, the subject stands with feet 25-30 cm apart, weight evenly distributed. Measurement is taken midway between the inferior margin of the last rib and the crest of the ilium in a horizontal plane. The measurer sits by the side of the subject and fits the tape snugly but not compressing soft tissues. Circumference is measured to nearest 0.1 cm. For hip circumference, the measure is taken around the pelvis at the point of maximal protrusion of the buttocks.

What is Obesity?

Thus, far we have been following the European conventional measurements of anthropometry to classify obese individuals. In our clinical experience too, we have observed that BMI severely underestimates the prevalance of obesity as defined by waist circumference and waist-hip ratio. So we were not certain about the prevalence of obesity in our population as well as in an individual patient. We compiled anthropometric data including BMI waist-hip ratio and waist circumference of 776 patients in our diabetes clinic. While only 28% patients were overweight (pre-obese) and 5.2% were obese by BMI, 69% were obese by waist circumference criteria when the conventional European values were used (Table IV). This had an abundance of subjects with increased waist circumference but 'normal' BMI and we were not clear in our mind whether to classify them as obese or not.

However, when we applied the proposed criteria, we found that about one-third of those patients who had abnormal waist circumference but normal BMI were 'appropriately' classified as either pre-obese/at-risk or obese. Though this illustrates that the proposed classification is suitable for our population, this has to be validated by studies in normal population with measurements of anthropometry including % body fat measures.

We believe that exclusive Asian anthropometric data and a classification based on that and validated by sophisticated anthropometric measurements will be very useful in identifying the subjects are risk for type 2 diabetes mellitus and cardiovascular diseases. This is especially relevant in view of the worsening 'epidemic' of non-communicable diseases in Asian countries which is resulting in significant morbidity and mortality apart from a great financial burden on these nations.

Table I : Classification of Weight by BMI in Adult Europids

Classification	BMI	Risk of Co-Morbidities
Underweight Normal Range Overweight > 25.0 Pre-Obese/At Risk Obese I Obese II Obese III	<> 18.5 - 24.9 25.0 - 29.9 30.0 - 34.9 35.0 - 39.9 > 40.0	Low Average Increased Moderate Severe Very Severe

Table II : Proposed Classification of Weight by BMI in Adult Asians

Classification	BMI	Risk of Co-Morbidities
Underweight Normal Range Overweight > 25.0 Pre-Obese/At Risk Obese I Obese II	<> 18.5 - 22.9 23.0 - 24.9 25.0 - 29.9 ≥ 30.0	Low Average Increased Moderate Severe

Table III : Co-Morbidities Risk Associated with

Different Levels of BMI and Suggested Waist

Circumference in Adult Asians

Classification	BMI	Risk of Co-Morbidities
		Waist Circumference
		<>	≥ 90 cm (men)
		<>	≥ 80 cm (women)
Underweight	<>	Low	Average
Normal Range	18.5 - 22.9	Average	Increased
Overweight	≥ 23.0
At Risk	23.0 - 24.9	Increased	Moderate
Obese I	25.0 - 29.9	Moderate	Severe
Obese II	≥ 30.0	Severe	Very Severe

Table IV : Classification of our Diabetic Population by

Conventional and Proposed Anthropometric Criteria

Classification	n = 776 (Type 2 Diabetes Mellitus Patients)
	Conventional European Criteria		Proposed Asian Criteria
Pre-Obese/At-Risk by BMI	218	28%	161	20.7%
Obese by BMI	41	5.2%	259	33.3%
Abnormal Waist Circumference	535	69%	598	77%

References & MCQs on What is Obesity? : Kindly refer to the March 2004 issue of the Medical Journal of Malaysia, Volume 59, Issue No. 1