|HEALTH & FITNESS|
Excessive exercise bad
New drug combo to
reduce heart attack risk
Asthma immunity may
lie in dust
How cancer is
Cancer has emerged as a major public health problem and still remains a lethal disease. In many countries more than a quarter of the deaths reported are attributable to cancer. According to a WHO report, 6.2 million people died of cancer in 2000. Global cancer rates could further increase by 50 per cent to 15 million by 2020. Is cancer an avoidable disease?
An avoidable cause of cancer is any contributing factor that increases the risk of cancer and is amenable to social or personal interventions that can ultimately keep people from developing the disease.
Evidence that cancer is preventable derives from observations of time trends and geographic patterns of cancer, birth cohort changes, high risks in groups with well-defined exposures, and experimental studies. Unfortunately, the magnitude and extent of the preventable causes of cancer are subjects of intense debate. There is much agreement, however, about the exposures that increase the risk —- notably, tobacco, alcohol, diet, radiation, medications, occupational exposures, general environmental exposures, and infectious agents. Interactions between carcinogenic exposures and genetic susceptibility are also important.
Nearly 50 per cent cancer cases are thought to be avoidable simply by stopping the use of tobacco and tobacco products, eliminating excessive alcoholic beverages, eating more fruit and vegetable-based diets, exercising to become more slim and fit and reducing/eliminating exposures to chemicals.
The incidences and mortalities can be further reduced by reducing exposures to "biological agents" known to cause cancer (e.g., hepatitis viruses, usually related to liver cancer, papilloma virus with cervical cancer, exposure to radiation and chemicals like benjene, arsenic, cadmium, asbestos, etc).
There is universal agreement that tobacco is the single most important avoidable risk factor for cancer. It causes not only lung cancer but also cancer of the bladder, mouth, esophagus, pharynx, larynx and cervix. Tobacco accounts for some 20-30 per cent of all kinds of cancer. Reduction in lung cancer in the US and the UK goes on to show the effect of reductions in smoking. In the US, strong public opinion has been built up against smoking. Excessive consumption of alcohol leads to a wide spectrum of harmful consequences.
Nearly 30 per cent of the cancer cases are in some way related to diet. Diets high in fat increase the risk of cancers of the breast, colon, prostate and uterus. Low fat diet renders some protection through the anti-carcinogens found in vegetables, fruits, nuts, and grains. High-fibre diet may protect against breast and prostate cancer. However, the possible roles of fat, red meat, fruits, vegetables and other factors need to be carefully assessed. More research is needed in this very difficult area. Diet-related cancer can never be eliminated, but it should be possible to reduce the risk based on the current knowledge.
A growing body of experimental and human evidence has identified other risk factors for cancer in addition to smoking. Because cancer is a disease with multiple causes, many of which are not susceptible to human intervention, any single contributing factor usually accounts for only a proportion of all cases. Currently at least 78 "agents" have been identified as causatively carcinogenic to humans with another 61 considered likely carcinogenic to humans. Still, efforts to identify these avoidable causes are a vital part of the public strategies to reduce the disease burden and promote health.
No matter how efficient we may become at delivering healthcare, we must also seek to reduce demand by keeping people from developing diseases in the first place. Recent analyses of cancer patterns indicate that we need to make a concerted effort to identify the avoidable causes in addition to smoking, and to apply knowledge already obtained about dietary, workplace, and other hazards to reduce the present cancer burden.
We must develop plans to avoid or modify the known cause of cancer. Scientists have an obligation to pursue opportunities to prevent cancer. Public education on the avoidance of identified risk factors like smoking and benefits of a healthy diet can help considerably in avoiding cancer.
The writer is Professor and Head, Department of General Surgery, PGI, Chandigarh.
Excessive exercise bad
With increasing health and fitness awareness, the battle of the bulge is becoming a ground reality. Since losing weight quicker has become an obsession with obese people, they tend to over-exercise. In such cases, the theory "more the merrier" does not hold true.
Patience and determination are the golden rule to lose weight systematically and effectively. Excessive training with the objective of shedding off the extra kilos quickly may lead to trouble.
Over-training is usually caused by periods of excessive training, which is more than the body’s ability to recover and adapt to the training schedule load.
Enthusiastic youngsters join a gym with the ambition to develop muscles like Salman Khan in a short span. These youngsters ultimately suffer from muscle injuries in the back, the neck and the shoulders. The rat race of engaging personal trainers or inexperienced coaches who have little formal training does not help.
Moderate exercise/training lowers the risk of heart disease, depression and day-to-day ailments. Problems start creeping in when one works too hard and too often or too long. Overtraining carries the risk of injury, muscle soreness, fatigue, depression, etc. Therefore, exercise should be progressively increased over a period of time. It is important to understand that exercise is a stress on the body, which has to adopt this stimulus by building up muscles and strengthening the cardiovascular and respiratory systems. By attempting to be too fit too fast, one does not strengthen one’s body through exercise; one actually attacks it and this may lead to health risks as mentioned below:
Symptoms of over-training
The ideal fitness regime is three days’ strenuous training (working 60-70 per cent of the maximum heart rate) and three days’ normal exercise (45 minutes to one hour) with one day’s rest. The off-day helps reduce muscle soreness/fatigue and rejuvenate the individual.
Your body needs to be recharged like batteries. After using it continuously for six days a week, one-day rest is a must.
The writer is a former doctor/physiotherapist, Indian cricket team.
LONDON: A combination of modern anti-hypertensive drugs can reduce a patient’s risk of stroke and heart attack to a greater extent than standard treatments, according to a study published in The Lancet.
In the Anglo-Scandinavian Cardiac Outcomes Trial (ASCOT), Bjorn Dahlof (Sahlgrenska University Hospital, Sweden) and colleagues compared the effect of combinations of older drugs-atenolol and thiazide-with newer drugs, amlodipine and perindopril.
Dr Dahlof comments: "The preferential reduction in cardiovascular events associated with an antihypertensive regimen of a calcium- channel blocker (amlodipine) with the addition of perindopril, if necessary, particularly when used in combination with effective lipid lowering, results in the prevention of most major cardiovascular events associated with hypertension. We hope these results will be used to inform clinical practice in ways that should greatly reduce the burden of cardiovascular disease to which patients with hypertension are exposed." — ANI
LONDON: In a new study scientists have found that knowing exactly which type of dirt provides the best "education" for the immune system could be the key to providing new treatment for diseases such as asthma.
Speaking at the launch of the BA Festival of Science, Professor Peter Openshaw explains that a lack of exposure to dirt and common viral infections among children could be behind the rise in the levels of asthma.
Professor Openshaw, from Imperial College, London, and based at St Mary’s Hospital, says: "Although we have seen a dramatic decline in many previously common childhood infections over the past 100 years, we have also seen a considerable rise in the prevalence of diseases such as asthma. The increase in asthma cannot be blamed purely on changes in genetic risk, so must be down to environmental factors."
Scientists have called this the "hygiene" hypothesis, with a lack of exposure to viruses and other environmental factors meaning children are not able to build up resistance, and can become more susceptible to disease later in life. They also believe having many older siblings, attending day care at an early age, or growing up on a farm can help in promoting resistance to disease.
Studies have shown that most common colds can help protect against wheezing in later childhood, and other childhood infections such as chickenpox also provide a level of protection.
Professor Openshaw adds: "The
challenge now is to find ways of reproducing the protective effects of
early childhood infections, while reducing the burden of actually
getting these infectious diseases.. — ANI