FOOD ESTHMA

Dr. P.N.B. Wijekoon MBBS (Cey), FRCP (Lond), FCCP
Consultant Chest Physician, Central Chest Clinic, Colombo

Diet was recognised as a possible contributory factor in asthma as long ago as the 19th century. Salter (1870) classified the provoking causes of asthma under three headings; “respiratory irritants, alimentary irritants and irritants affecting the nervous system.”

By the early 20th century dietary restrictions were (and still are, in eastern cultures) part of standard advice given to patients.

However, in the late 1940’s, it was increasingly recognised that dietary restrictions may do more harm than good, possibly by causing deficiencies in essential vitamins and trace elements such as pyridoxine, ascorbic acid, nicotinic acid, sodium, magnesium, selenium and polyunsaturated fatty acids.

Some of these deficiencies have been postulated (but not proven) to worsen asthma.

Asthmatic patients’ attribute

In Sri Lanka, many asthma patients attribute exacerbations of their asthma to various foods, especially sour plantains, king coconut water, tomatoes, aubergines, pineapples and iced carbonated drinks. Indeed, some patients in Sri Lanka chiefly attribute worsening of their asthma to changes in weather, bathing in cold water and certain foods.

Whether these factors actually worsen asthma is unsubstantiated, as no definitive controlled studies have been done. However they cannot be dismissed out of hand. In the western countries, peanuts are such a potent factor in causing exacerbations of asthma, even death, that many food items display prominently on the package whether they do or do not contain nuts.

In the same way, it is possible that some foods indigenous to Sri Lanka, and the pesticides they may contain, do cause exacerbations of asthma. Some foods can produce bronchospasm via an IgE mechanism in sensitized individuals. These include nuts, fish, shellfish, eggs and various seeds. Co-existence of unstable asthma and peanut allergy is particularly dangerous and has led to a number of deaths.

Food additives

Several chemicals that are used as additives in food and drug preparations have been associated with worsening of asthma and should, wherever possible, be avoided.

Tartrazine

Tartrazine, (E102), a yellow dye, is used as yellow colouring in many foods, confectionaries, beverages such as cordials, carbonated drinks and drugs. Tartrazine sensitivity may affect up to 4% of asthmatics, especially children, and cause bronchoconstriction and urticarial rashes.

Metabisulphites

Bisulphites and metabisulphites are antioxidants used as preservatives in several foods such as sausages, fruit cordials, salads, beer and certain medications. They typically produce bronchoconstriction within 30 minutes of ingestion and this is probably related to the release of sulphur dioxide (SO2) after ingestion, since sulphur dioxide is known to provoke bronchoconstriction in some asthmatic subjects.

Monosodium Glutamate

Monosodium glutamate (MSG, E621) is a flavour enhancer, used in soy sauce, Chinese food, hamburgers and spices. Some people react with sweating, flushing and numbness of the chest. In patients with asthma, this may be accompanied by wheezing (Chinese Restaurant Asthma Syndrome). An attack of asthma induced by MSG may be severe and it may be difficult to establish cause and effect as symptoms may not appear until 12 hours after ingestion.

Cow’s milk allergy

There is widespread belief in some communities that cow’s milk allergy is a potent cause of asthma. This is not true. Cow’s milk allergy usually presents as cutaneous and/or gastro intensital symptoms. Respiratory manifestations are uncommon.

Breast Feeding: The evidence for a protective effect of breast feeding against the development of asthma is conflicting. A systematic review and meta-analysis involving 8183 subjects followed for 4 years revealed a significant protective effect. However a more recent study involving 1246 patients found that breast feeding was associated with a reduced risk of infant wheeze but with an increased risk of asthma at six years.

Dietary manipulation

Minerals: Low magnesium intakes have been associated with higher prevalence of asthma. Studies of sodium, magnesium, and antioxidant supplements such as selenium and vitamin C have produced little or no evidence of benefits amongst patients with asthma.

(Courtesy: SLMA guidelines on The Management of Asthma - sent by Mrs. Chissy Aloysius President Doctors Wives Association)

Jealous about the slim neighbour?

Yah... Watching neighbours is a pastime for some. Anyway do you know anything about their eating habits. Yes, she’s slim... Don’t feel jealous. It’s the science of nutrition. Let’s dig deeper into this issue. How can some people seem to eat whatever they want and not put on weight, while others seem to pile weight on just by looking at food?

While this is a gross exaggeration of what really happens, there is certainly some truth in the fact that some ‘thin’ people seem to be able to eat more and gain less. One of the reasons for this is “metabolism”, or more correctly, the rate of “basal metabolism”. Big words ha..

Basal Metabolism

Your Basal Metabolic Rate (BMR) is the number of calories you burn just by sitting or lying in an inactive state. Breathing, maintenance of your body, including body examples of functions that help contribute to the rate of basal metabolism. A number of things affect your basal metabolic rate. Ever noticed that every year, it becomes harder to eat whatever you want and stay slim? That’s because your BMR decreases as you age.

Decreases your BMR the completely opposite effect to the one you desired.

In compact, increasing lean mass (including muscle) can increase your basal metabolic rate. Taller people and men also have a higher BMR.

Obviously you can’t do too much about your height, but you can reduce your body fat content and increase your lean muscle mass.

Finally, exercise also increases your BMR, so you get the dual beneficial effect exercise burns energy (which can come from your fat stores), and it also increases your basal metabolic rate. So even when you’re sitting still, you’re burning up calories. Courtesy Slimlife

An egg a day increases risk of death

Dr D.P. Athukorale

People who ate one egg or more eggs per day had an almost 25 percent increased risk of death in a 20 year period compared with those who generally avoided eggs according to Harvard Physicians Health Study. For participants with diabetes, the risk of death was two fold. The study included 21327 participants with an average 20 year follow-up.

One large egg contains approximately 215 milligrams of cholesterol more than any other common food. Eggs also contain saturated fat and animal protein.

Reference: Djousse L and Gaziano J.M., American Journal of Clinical, Nutrition, 2008, 87, 964-969

 

Scientists develop new cancer-killing compound from plant

Researchers at University of Washington have updated a traditional Chinese medicine to create a compound that is more than 1,200 times more specific in killing certain kinds of cancer cells than currently available drugs, heralding the possibility of a more effective chemotherapy drug with minimal side effects.

The new compound puts a novel twist on the common anti-malarial drug artemisinin, which is derived from the sweet wormwood plant. Sweet wormwood has been used in herbal Chinese medicine for at least 2,000 years, and is eaten in salads in some Asian countries.

The scientists attached a chemical homing device to artemisinin that targets the drug selectively to cancer cells, sparing healthy cells. The compound kills 12,000 cancer cells for every healthy cell, meaning it could be turned into a drug with minimal side effects. The results were published in the latest issue of journal Cancer Letters.

“The compound is like a special agent planting a bomb inside the cell,” said Tomikazu Sasaki, chemistry professor at UW and senior author of the study.

A cancer drug with low side effects would be more effective than currently available drugs, since it could be safely taken in higher amounts, he said. In the study, the UW researchers tested their artemisinin-based compound on human leukemia cells. It was highly selective at killing the cancer cells.

The researchers also have preliminary results showing that the compound is similarly selective and effective for human breast and prostate cancer cells, and that it effectively and safely kills breast cancer in rats, Sasaki said. – Enditem

Policy on commonly used antibiotics urgently needed

Professor Sanath Lamabadusuriya last week stressed on the need for the health authorities to formulate a policy on the use of some of the commonly used antibiotics to save some of the diseases causing bacteria building up resistance to them.

He said medical professionals have been talking for sometime to the Health authorities on this but unfortunately upto now they seem to have not moved on this and the doctors find the problem of controlling some of the common diseases with less expensive commonly used antibiotics.

Prof. Lamabadusuriya was speaking on a Edna pharmaceuticals organised talk on the implications of pneumonia in infants and children in Sri Lanka at Taj Samudra Hotel Colombo.

Prof. Lamabadusuriya observed the consequences of a drug being used and misused on a large scale are once again beginning to emerge. Only this time, the drug involved, is one of the most potent to fight bacterial infections responsible for killing nearly one million young children every year in the world.

The drug in question is Penicillin, one of the wonder drugs of the last century. And the bacterial infections being discussed are Pneumococcal infections - pneumonia, meningitis and sepsis, which are caused mainly by two types of bacteria (Streptococcus Pneumonia and Hemophilus influenza). According to WHO, pneumococcal infections are becoming difficult to treat as bacteria are turning more resistant to the commonly used antibiotics.

Serious pneumococcal infections occur throughout life, but young children (especially those under 2 years old) and the elderly are at the highest risk for severe pneumococcal disease. According to the SAPNA surveillance pneumococci is responsible for 31 per cent of Meningitis, 33 per cent of Sepsis and 33 per cent of Pneumonia in Sri Lankan children. The mortality rate due to meningitis is very alarming. Even if children escape death, morbidity is severe. They very often develop residual damage such as, hearing loss and paralysis of the limbs.

What is more appalling is that, with both types of bacteria (S. pneumonia and H. influenza) causing pneumonia, meningitis and sepsis, mere clinical observations sans laboratory testing difficult to identify the causative bacteria, which makes treatment more difficult.

Treatment with antibiotics without confirmed laboratory test reports is a sure bet for bacteria developing resistance to drugs. Even when properly treated, the drug gets into the environment and in due course helps the bacteria develop resistance to it. Its misuse only aggravates and hastens the process.

There is a compelling need to put in place proper systems that will ensure that drug resistance does not set in. And for that to happen, equal responsibility rests with all stakeholders - government, doctor’s and patients.

The government for strengthening the laboratory facilities in hospitals, doctors for prescribing correct drugs and in correct dosages and only when required, and finally the patients who should adhere to and complete the regimen.

Laughter the Best Medicine

One day a teacher came into her classroom and found a very rude word chalked on her blackboard. “I’m not going to scold, she said. We are going to take care of this by the honour system. We will all close our eyes, and I will count up to 100. When we open our eyes whoever wrote that would have tiptoed up to the board and rubbed it out.”

Everyone closed their eyes. ‘One... two... three... pitter patter... 48... 49.... 50 squeak, squeak... 99, 100.’

Everyone opened their eyes and there, on the board, was another, even filthier word and above it was chalked, ‘The phantom writer strikes again.’

(Courtesy - Playground Jokes)

Feed children.... not too much

A review article published in the Journal of the American Dietetic Association suggested that overnight and morning fasting (skipping breakfast) had a negative effect on memory for children who were at risk (data on children who were well-nourished to begin with was inconclusive).

Another study suggested that children who eat breakfast had gains in maths, reading and vocabulary.

So, do not fear to feed your children. Good diet is a must for a future president! But, you think about the food pyramid, which we designed for you. Balance it.... It’s the secret.