Ban antibiotics in animal feeds

alt

Several studies on our meats like chicken (both imported and local), beef, mutton and frozen burgers have found an alarmingly high incidence of antibiotic-resistant bacteria in them.  Eating foods contaminated with such bacteria can cause life-threatening complications as the treatment of such cases may be difficult.

The indiscriminate use of antibiotics in animal feeds has caused the spread of antibiotic-resistant bacteria in farm animals. The spread of such bacteria in our meats is alarming and poses a serious health threat to consumers.

In a study carried out by the Department of Veterinary Services (DVS) in 2012, half of the domestic chickens were resistant to ampicillin, sulphonamide and tetracycline. The situation was worse with imported chicken: 87% ampicillin-resistant, 75% nalidixis acid-resistant, and 50% streptomycin- and sulphonamide-resistant.

The study also found 13.5% Tetracycline-resistant Salmonella; 5.4% Polymixin B and Erythromycin-resistant Salmonella and 2.7% Chloramphenicol, Penicillin G and Trimethoprim-resistant Salmonella in local chicken.

Food samples such as beef, mutton and chicken had antibiotic-resistant Salmonella. About 6.28% of the resistant Salmonella was isolated from imported products (44.2% beef and 18.6% chicken).

Salmonella causes diarrhoea (sometimes bloody), fever, and abdominal cramps. Resistant infections are more severe and have higher hospitalisation rates. Salmonella is showing resistance to more classes of antibiotics and is a serious public health threat.

In another study of live chickens sold at wet markets in Selangor, of the 90 chickens examined 68 (75.6%) were positive for Campylobacter. The most frequently observed resistance was to cephalothin (95.5%) followed by tetracycline (80.8%), erythromycin (51.4%), enrofloxacon (42.4%) and gentamicin (24.4%). Multidrug resistance (resistant to three or more antibiotics) was detected in 35.3% isolates (bacteria samples).

Like Salmonella, Campylobacter spreads from animals to people through contaminated food, especially raw or undercooked chicken. It causes diarrhoea (often bloody), fever and abdominal cramps, and sometimes causes serious complications such as temporary paralysis, and even death. Resistant Salmonella, Campylobacter and E.Coli infections have spread worldwide through travel and food trade.

In 2005, the USFDA withdrew approval of fluoroquinolones used in poultry (currently used in Malaysia) as this class of antibiotics causes resistant Campylobacter in poultry which are transferred to humans and may cause fluoraquinolone resistant Campylobacter infections to develop in humans.

In addition, local researchers also found the presence of multidrug-resistant strains of Listeria monocytogenes bacteria in frozen burger patties taken from supermarkets and other retail shops in the country.

Commonly found in raw foods, L. Monocytogenes can cause listeriosis. Common symptoms include gastrointestinal upset, headaches, fever and in severe cases, brain infection and or blood poisoning.

This study examined the susceptibility of L. Monocytogenes isolated from raw beef, chicken and vegetarian patties to 11 different antibiotics. 28 out of 41 bacteria samples were resistant to at least one and 19 were resistant to at least two antibiotics. Tetracycline, followed by erythromycin resistance, were the most common forms of resistance.

Antibiotics widely used in animal feeds

alt
In livestock production, antibiotics are given to animals for a number of different reasons: treatment, prevention of disease and primarily growth promotion. Antibiotics are routinely added to animal feed or their drinking water. Antibiotics that are used as growth promoters are generally not even considered as drugs and are either not licensed or licensed solely as feed additives.

Most, if not all, of the antibiotics given to animals are medically used for humans. According to the World Health Organization (WHO), use of antibiotics in animal husbandry is generally not based on sound scientific principles.

In Malaysia, there are currently 97 antibiotic drugs registered for use. Most of these registered drugs are used in poultry and pig farms, less in cattle and goat farms. More than half of the antibiotics (active ingredient) registered with the Ministry of Health for food animals are not recommended for veterinary use by the WHO.

It can be seen that antibiotics are widely used in food-producing animals and this contributes to the emergence of antibiotic-resistant bacteria in these animals, which are of particular concern because these animals serve as carriers.

Marketing and promotional practices of antibiotics for therapeutic, proplylactic or growth promoter uses in animals by industry influence the prescribing patterns and behaviour of veterinarians, feed producers and farmers.

Resistant bacteria can contaminate the foods that come from those animals and people who consume these foods can develop antibiotic-resistant infections. There is now increasing evidence linking newly emerging resistant bacteria in animals being transmitted to humans mainly through meat and other food of animal origin or through direct contact with farm animals.

Food borne disease causing bacteria like Salmonella and Campylobacter have become resistant to classic treatment in humans as a result of the use of certain antibiotics in agriculture.

In the most recent tragedy in the first week of October, four people died and 60 others were hospitalised after eating contaminated food during a wedding feast in Kedah. The Health Department has singled out the chicken dish as the possible cause of food poisoning from Salmonella contamination (New Straits Times, 2 October 2013).

Antibiotics in food animals also leads to transfer of resistance genes which could be passed from animals to humans via harmless bacteria in food products and the resistant genes could then be transferred to disease causing bacteria in the human gut. The presence of similar vancomycin and cephalosporin resistant genes in both human and animal bacteria supports this view.

Because of the link between antibiotic use in food-producing animals and the occurrence of antibiotic-resistant infections in humans, antibiotics should be used in food producing animals only under veterinary supervision. According to the US Centers for Disease Control and Prevention antibiotics should only be used to manage and treat infections for animals.

It is clear the high incidence of antibiotic resistant bacteria in our meats that there are problems with the Livestock Farm Practices Scheme (SALT) which is to ensure that farms practising Good Animal Husbandry Practices (GAHP) produce safe and wholesome food of good quality, in sustainable and environmentally friendly conditions.

SALT certification is awarded to farms that meet criteria of GAHP, Animal Health Management, Bio-security, good infrastructure and prudent use of drugs. The certification scheme covers all types of livestock i.e. beef cattle, dairy cattle, broiler chicken, layer chicken, breeder chicken, deer, goat, sheep and pig.

Yet more than half of the domestic chicken harvested from the SALT certified farm in the DVS study were resistant to three classes of antibiotics i.e. ampicillin, sulphonamide and tetracycline. The situation was worse with imported chicken, as noted above.

Urgent and strong measures needed

There are clear indications that some SALT certified farms are unable to meet Good Animal Husbandry Practices. It is unclear if the causes are lapses in hygiene standards, imprudent use of drugs or lack of the required infrastructure. The fact that imported meat products have shown higher percentages of resistant strains of Salmonella points to lapses in monitoring and enforcement.

In view of the above, CAP urges the Ministries of Health and Agriculture to:

• Ban antibiotic use in animal feeds in light of the EU ban on antibiotics in animal feed.
• Create a national system to monitor antibiotic use in food animals. This includes actions to improve and refine the collection of data on antibiotic use in the country. Quantities and classes of antibiotics used in food animals according to animal species need to be documented. This is necessary for risk analysis, interpreting resistance surveillance data and to assess the impact of interventions to promote prudent use;
• Monitor resistance and track changes in antibiotic resistance through on going surveillance at local, state and national levels. This will identify emerging health problems so that timely corrective action to protect human health is taken;
• The containment of antibiotic resistance must be made a national priority. There is a need to create a national intersectoral body or task force comprising healthcare professionals, veterinarians, academics, agricultural scientists, consumers, the media, to raise awareness about antimicrobial resistance (AMR), prioritise research, collect data, recommend policy measures to contain AMR eg formulating principles for a new Animal Health Law;
• Develop guidelines for veterinarians to reduce the overuse and misuse of antibiotics in food animals;
• Provide education and training for livestock farmers on responsible use of antibiotics;
• Encourage good farming practices and best practices in disease control eg appropriate housing design for animals, good disinfection procedures, isolation of sick animals, use of vaccines and disease eradication programmes;
• Monitor imported meat products for antibiotic resistant contamination and the stringent enforcement of rules;
• Identify foods local and imported responsible for outbreaks of Salmonella infections and other food borne contamination;
• Monitor the spread of Salmonella among animals on farms to prevent their spread.
• Educate consumers and food workers about safe food handling practices and how to avoid Salmonella infections.     

Press Statement – 10 January 2014

bull; Educate consumers and food workers about safe food handling practices and how to avoid Salmonella infections.

Stay away from soft drinks

alt
Consumers Association of Penang (CAP) calls upon the Malaysians to stay away from sweetened soft drinks which have proven to be a threat to our health.  
Soft drinks contain approximately 6 to 12 teaspoons of sugar and the number of these drinks being consumed by Malaysians is increasing daily.  According to a recent news report 1,000 canned drinks are consumed every minute in Malaysia.
Due to our warm and humid weather, soft drinks are a craze for Malaysians who look for a quick thirst quencher. In doing so, we actually end up consuming a substantial amount of sugar in the drinks which actually dehydrates our bodies further. Children have a greater desire for soft drinks due to its high sugar content and which come in attractive colours and flavours.  The easy availability of soft drinks at affordable prices makes Malaysian consumers fill their shopping trolleys with a variety of soft drinks when they go shopping.  Their children take this opportunity to grab their choice of soft drinks without any objection from their parents.

Most soft drinks are nothing but carbonated, coloured, acidified, flavoured, sweetened water which spells danger to our health.  Despite this soft drinks are the beverage of choice for millions of Malaysians.   They are also a prime source of extra calories that can contribute to unhealthy weight gain.  Once thought of as an innocuous refreshment, soft drinks now come under scrutiny for their contributions to the development of type 2 diabetes, heart disease and other chronic conditions. 

According to some scientists, fructose sugar in some soft drinks acts like a fat.  Unlike other sugars, which are broken down by other organs of the body, fructose heads straight to the liver and is deposited as fat.

High phosphoric acid levels in soft drinks inhibits the growth of bone. Studies show that children who frequently drink soft drinks are more vulnerable to broken bones in addition to childhood obesity and diabetes.  

Questions may arise in the minds of Malaysians as to what to serve to their families and friends if not soft drinks especially during festive seasons.  As we are all aware, Malaysians inherit a very rich food culture.  If we could make an effort to revive traditional recipes we could create our own soft drinks which are healthier and cheaper. These traditional drinks are not only tasty and refreshing but also carry medicinal values.  Elderly people in our homes could guide us on this.  A bit of extra work can do wonders to preserve our health.

The festive season is meant to be a season of joy and it is our responsibility to ensure that this joy manifests itself in health and longevity.  Enjoying festive seasons with sugary soft drinks and ending up with life threatening diseases defeats the very purpose of the festival.  

Press Statement – 7 September 2010

See the actual amount of sugar found in soft drinks in CAPs Sugar Infoslides

 

Malaysians are the 8th largest sugar consumers in the world

The Consumers Association of Penang (CAP) is concerned that sugar consumption among Malaysians is increasing at an alarming rate. The high sugar intake is reflected by the serious health problems and debilitating diseases striking Malaysians each day.
Early in 2009 Datuk Shahrir Abdul Samad the former Minister of Domestic Trade and Consumer Affairs announced that Malaysia is the 8th highest sugar users in the world.

In the 1970s, Malaysians consumed about 17 teaspoons of sugar a day. This figure went up to about 21 teaspoons a day in the 1980s. By the 1990s Malaysians were consuming an average of 24 teaspoons of sugar per day but now the figure has jumped to 26 teaspoons.

Sugar is a very widely eaten nutrient-free food which, unfortunately, is not generally seen as a dangerous substance. Sugar is totally unnecessary from the physiological point of view. According to the World Health Organisation journals, it is not necessary to have even an ounce of sugar in the diet.

Professor John Yudkin, author of the highly acclaimed book on the hazards of sugar, Pure, White and Deadly agrees. In his opinion, “All human nutritional needs can be met in full without  having a single spoon of sugar, white or brown, on its own or in any drink or food.” In other words, sugar is not a necessity in our diet.

Sugar has been linked to over 60 ailments from cancer, diabetes, obesity, heart problems, osteoporosis and kidney problems to asthma and allergies. Some of these killer diseases are showing worrying upward trends in just a few years.

According to the Health Ministry’s statistics, 11.6 million of the 16 million adults nationwide are sick with a non-communicable disease like diabetes, hypertension or cancer.

Malaysia has the most overweight and obese people in Asia. 54% of the adult population is either obese or overweight, compared to only 24.1% 10 years ago. As a result, 7 out of 10 Malaysian adults suffer from chronic diseases.

For example, according to the International Diabetes Institute, Malaysia has the 4th highest number of diabetics in Asia. From 800,000 recorded diabetics in 2007, the number is expected to increase to 1.3 million in 2010.

In the first National Health and Morbidity Survey (NHMS) carried out in 1986, the prevalence of diabetes was 6.3%. The figure increased to 8.3% in 1996 and the latest 2006 NHMS revealed that the diabetes prevalence has increased to 14.9%.

Diabetes and end stage renal failure are already a big health problem in Malaysia. It is estimated that there are 13,000 kidney patients undergoing dialysis and every year 2,500 people join the ranks of end-stage renal failure patients.

Another major health concern is that 4 out of 5 people with diabetes will die of heart disease (the number 1 killer in the country). 6 new cases of stroke occur every hour in Malaysia.

Most people find it hard to believe or accept that they can be consuming an average of 26 teaspoons of sugar a day. That is because we may be thinking only of the “visible” white sugar we see and buy for use at home. However, an increasing amount of sugar consumed by the public is in industrially-prepared drinks and food.

Some soft drinks contain an average of at least 7 teaspoons of sugar per can. CAP surveys noted a number of the commercial drinks and food contained over 10 teaspoons of sugar in just one serving. Consumers are often unaware of how much sugar they consume in total in a day.

In view of the alarming health condition Malaysians are facing, urgent action needs to be taken to curb our national sugar consumption.

CAP calls on the Government to:

– Work with manufacturers to reduce sugar in their products.
– Require manufacturers to amend their labels to clearly indicate the amount of sugar in their food. In order for consumers to understand the information, the sugar content could be shown graphically in terms of the number of teaspoons of sugar. (One teaspoon is approximately equivalent to 5g).
– Institute “traffic light” labelling to enhance consumer awareness. This has been effective in enabling consumers to assess the significance of nutrient levels within a particular product, and allows for comparison between products. Under this scheme, red, orange and green colour coding would indicate whether the levels of these ingredients of concern are high, medium or low. The presence of the red, orange or green signals on food packaging would serve as an instant notice for consumers – even children or those with limited nutritional knowledge or numerical skills would easily be able to comprehend these signals.
– Stop the advertisements of highly-sugared and other junk food and drinks during children’s television viewing hours.
– Educate school children on the dangers of excessive sugar intake through health education, home science and cooking lessons. Educate the public on the dangers of sugar intake through the media.
– Encourage children to avoid sweet drinks in schools by providing drinking water in water dispensers around school premises. Sweet drinks should not be sold in canteens so that children learn to select water as a first-choice drink.
– Ban the sale of junk food in school canteens and food hawking within a fixed perimeter around schools so that schoolchildren are not tempted to purchase unhealthy food.
– Initiate the removal of vending machines dispensing junk food and sugary drinks from areas such as hospitals, airports and schools. Instead, provide drinking water in water dispensers at these places.
– Launch a massive campaign in the mass media to educate the public on the ill effects of sugar.

Read more about the destructive effects of sugar in the CAP Guide, How Sugar Destroys Your Health

 

Heart dangers of caffeinated energy drinks

A recent report of a life-threatening heart attack in a young healthy male suggests care is needed with caffeinated energy drinks.

Caffeinated energy drinks are widely promoted to give people the buzz and lift needed to get through a tough day. One such tough day became even more “arresting” for a healthy 28-year-old male.

As reported in the Medical Journal of Australia (2009;190:41-43), a motocross rider looking for that little bit extra consumed up to 8 cans of caffeinated energy drink throughout a tough day of competition.

Around 3pm, 20 minutes after his last race, he collapsed. When paramedics arrived, his heart was fibrillating (fluttering). Emergency cardiac shock treatment and drug administration saved his life. He was rushed to the local hospital where he remained under close observation for the next 6 days.

Sudden deaths, or near misses, are extremely rare in people under the age of 40, especially in those without obvious risk factors. In this man’s case, the likely culprit was the ingestion of the caffeine. Each can contains 80mg of caffeine, giving a total dose of around 640mg over the 7-hour period.

Reports of life-threatening responses to caffeine at the level consumed by the rider are rare. However, some energy drinks, including the brand consumed by this man, also contain the amino acid taurine. Taurine, like caffeine, affects the functions of calcium in cells. Calcium is required for electrical signals, critical for heart function. The cardiologists who managed this person in recovery have suggested that perhaps the combination of high caffeine and taurine intake in susceptible people could trigger a heart attack.

With the same levels of caffeine in each drink as an espresso coffee, caffeinated energy drinks pack a real punch. They are not an ideal substitute for sports drinks (or even plain water) in providing effective hydration. — CHOICE Health Reader, March 2009

Red meat raises your risks of cancer, heart disease & diabetes

“Eating Meat May Increase Risk of Early Death, Study Finds,” ran the headline in The New York Times in March. “Dying for some red meat? You may be,” quipped the Los Angeles Times. The big news came from a study that tracked more than half a million Americans aged 50 to 71 for 10 years. Those who reported eating the most red meat were roughly 30% more likely to die mostly of cancer or heart disease than those who reported eating the least.
“You don’t have to be vegetarian to be healthy,” says Walter Willett, chair of the department of nutrition at the Harvard School of Public Health. “If you go from eating meat twice a day to once a week, you can eliminate most of the risk.”

Here’s the evidence that red meat is hazardous to your health.

Cancer, heart disease, diabetes… all have been linked to red meat (mostly beef and pork), processed meats (bacon, ham, hot dogs, sausage, and deli meats), or both.

The evidence is stronger for some diseases than others. “But even if only a couple were true, when you put them all together, that would be reason enough to keep red and processed meat consumption pretty low,” says Harvard’s Walter Willett.

Here’s what we know about the risks of eating red and processed meats, and how to minimise them.

The Study

In 1995, the NIH-AARP Diet and Health Study sent questionnaires about diet and lifestyle to 3.5 million members of AARP (formerly known as the American Asso­ciation of Retired Persons). 10 years later, researchers from the National Cancer Institute analysed results from half a million of them.

“At the high end, people who consumed 2,000 calories a day ate about 5 ounces of red meat a day,” notes Barry Popkin, director of the Nutrition Epide­miology Division at the University of North Carolina Gillings School of Public Health in Chapel Hill. “That’s just over 11/2  Quarter Pounders or Big Macs a day.”

Their risk of dying over 10 years — mostly of heart disease or cancer — was roughly 30% higher than the risk of those who ate the least red meat. “People at the low end averaged two-thirds of an ounce of red meat a day,” says Popkin.

Processed meats had less impact than red meats. People who ate the most ate almost 2 ounces a day. “That’s equal to about one hot dog a day,” says Popkin. It’s also a ham or smoked turkey sandwich. Their risk of dying was roughly 20% higher than the risk of those who ate the least processed meat. The “least” group ate the equivalent of one hot dog every 2 weeks, though the risk for the next-to-least group — which ate the equivalent of about one hot dog a week — wasn’t much higher.

And “white meat” — chicken, tur­key, and fish — posed no risk. In fact, those who ate the most had slightly lower odds of dying than those who ate the least.

The bottom line: “People really need to cut down on red and processed meat,” says Popkin, who wrote an editorial that was published along with the study. “You can’t stop to get a hot dog every day when you’re walking down the street.”

Of course, it’s also possible that some­thing else about meat eaters in the NIH­AARP study raised their risk of dying. “People who eat a lot of red meat eat and drink differently,” says Popkin. “The researchers did all they could to control for the differences.” They looked at everything from weight, education, and smoking to alcohol, vitamin use, fruit consumption, and more. But they could still have missed — or incompletely accounted for — something other than meat that raises a meat eater’s risk of dying.

“This is the biggest study to look at meat and mortal­ity, and it was done as well as you can do it,” says Popkin. ‘”The only way to get around differences in meat eaters is to do a clinical trial” — that is, to randomly assign people to ‘ diets with more or less meat and wait 5 or 10 years. “And you can’t do that on half a million people.”

How might meat raise the risk of dying? Here’s what we know so far.

Heart Disease

It’s no shock that meat eaters are more likely to die of heart disease. “A lot of the higher risk is coming from the high amount of saturated fat and cholesterol,” says Har­vard’s Walter Willett. It’s clear that saturated fat and choles­terol raise blood cholesterol, which boosts the risk of heart attacks. Although some cuts of meat — like sirloin, filet mignon, and pork tenderloin — are leaner than oth­ers, meat is still one of the largest sources of saturated fat in the average American’s diet. And you can’t trim the fat off ham­burgers, hot dogs, sausages, or bacon.

“In general, the best evidence comes from a combination of epidemiological studies that look at the disease itself plus risk factors like blood lipids and blood pressure,” explains Willett. “You’ve got that combination of evidence for red meat.” What’s more, what you eat instead of meat may protect your heart. “We’ve published studies showing that replacing meat with chicken and fish would be advantageous,” notes Willett.

That’s partly because chicken and fish have less saturated fat than red meat and partly because the omega-3 fats in fish may lower the risk of heart attacks. “You’re better off replacing meat not just with fish and chicken, but also with some nuts, beans, soy products, and other plant proteins,” says Willett. They’re rich in fibre, vitamins, and minerals, and the unsaturated fat in nuts can help lower blood cholesterol.

Colorectal Cancer

“When it comes to red and processed meats, the evidence has always been strongest for colorectal cancer,” says Arthur Schatzkin, chief of the Nutritional Epidemiology Branch of the Division of Cancer Epidemiology & Genetics at the National Cancer Institute in Bethesda, Maryland. Schatzkin was a co-author of the NIH-AARP study. Before NIH-AARP, Swedish research­ers who examined 15 studies reported a 28% higher risk of colorectal cancer in red-meat eaters and a 20% higher risk in processed-meat eaters.

“The evidence linking high consump­tion of red and processed meat to in­creased risk of colorectal cancer is highly consistent,” says Michael Thun, vice president of epidemiology and surveil­lance research at the American Cancer Society. When it comes to food, “only the relationship between obesity and cancer is stronger”.

How might red and processed meat cause malignant tumours in the colon and rectum? There are 2 key explanations: N-nitroso compounds (Nitrites are added to processed meats like bacon, hot dogs, sausage, and bolo­gna to preserve and colour the meat). Scientists have known for decades that N-nitroso compounds cause cancer in laboratory ani­mals. So back in the 1970s, when carcinogens were discovered in cooked bacon, researchers came up with a fix. “When the meat industry realised that N-nitroso compounds were being formed in meats that had nitrites added, they started to add ascorbic acid to the meats,” explains Amanda Cross, a co-author of the NIH-AARP study who works with Schatz­kin at the National Cancer Institute.

Nearly all processed meats now contain either sodium ascorbate (Vitamin C) or its cousin sodium erythorbate. They prevent the N-nitroso compounds from forming in the meat, but that doesn’t entirely solve the problem. Recent studies indicate that N-nitroso compounds can form in the gut when people eat processed meats, and giving them Vitamin C doesn’t stop it. In fact, any meat may trigger the reaction. “When we did some feeding studies with non-processed red meat, we found that a considerable amount of N-nitroso com­pounds still form in the gut,” says Cross.

For N-nitroso compounds to form, you need amines and amides, which come from protein, plus a nitrosating agent, which can come eitherfrom nitrites in processed meats or from nitrates that can be converted to nitrites in the mouth and elsewhere in the body. “Nitrates can come from water and some vegetables,” Cross explains. At first Cross thought that more amines and amides in the gut would mean that more N-nitroso compounds would form. “But when we tried feeding a high-protein white meat diet or a high protein vegetarian diet, we didn’t see an increase in N-nitroso compound formation,” she says. N-nitroso compounds only increased after red meat, suggesting that the meat’s heme iron might be at fault. (Heme iron gives red meat its colour.) “We think heme iron is catalysing the reaction between the amines and the nitrosating agent,” explains Cross.  “When we fed non-heme iron, we didn’t see an increase in N-nitroso formation in the gut at all.” Non-heme iron is found in grains, beans, leafy greens, and iron-containing vitamin supplements, cereals, and other fortified foods. “So we think it has more to do with how much heme iron and bacteria are there,” says Cross. The normal bacteria that live in your gut seem to play a key role. “If you feed these nitrates to rats that have no bacte­rial flora, you do not see N-nitroso com­pound formation,” says Cross. “If you add bacteria, you see an increase.” And some people have bacteria that produce far more N-nitroso compounds than others.

Cooked meat mutagens. Grilling meat or cooking it at high temperatures creates two classes of mutagens — heterocyclic amines (HCAs) and polycyclic aromatic hydrocarbons (PAHs). (A mutagen causes changes in DNA, which can lead to cancer.) To the body, they’re foreign sub­stances that need to be expelled. “Because the body really wants to get rid of HCAs, the liver adds oxygen to them and other parts of the body add acetyl groups to make them more soluble,” says Rashmi Sinha, deputy chief of nutritional epidemiology at the National Cancer Institute. Once soluble, they can be washed out in the urine.

Ironically, the efforts to get rid of HCAs can make them more dangerous. “In some cases, that can make them more active and damage DNA,” says Sinha. Her research is trying to identify the genes that make HCAs more active. “It’s not one gene,” she notes. “It’s a multi­step pathway, so it would have to be a combination of genes.” In the meantime, consumers can avoid cooking meat at high temperatures and   for a long time. “The more brown the meat is, the more likely it is that hetero­cyclic amines have formed on the surface,” says Sinha. They’re there, she adds, “when it’s that nice crusty brown.” Marinating meat before cooking it may remove compounds that turn into HCAs. So does microwaving. “It gets rid of some of the precursors,” explains Sinha. The goal is to minimise high-temperature cooking. “A simple way to think about it is if water is available — like when you’re stewing — the temperature of the meat never rises above the boiling point of water,” says Sinha.

Also critical: “You have to minimise how long you keep the meat on the grill.” Both less time and lower temperatures matter. And it’s not just red meat. “Chicken produces a lot of heterocyclic amines,” says Sinha. “But in the NIH-AARP study, we didn’t see an increased risk from poul­try.” In fact, people who ate more white meat — chicken, turkey, and fish — had a slightly lower risk of dying. One explanation: “The majority of the population — close to 60% — doesn’t eat grilled chicken,” says Sinha. “They eat roast chicken, which doesn’t have these compounds, even if it’s well done.”

Another problem occurs when the fat from grilled meat or poultry drops onto the fire or electric element. The heat cre­ates polycyclic aromatic hydrocarbons (PAHs), which travel via smoke to the meat’s surface. It’s a double whammy. “Smoked and grilled meat and poultry   have both heterocyclic compounds and polycyclic hydrocarbons,” says Sinha.

Overall, the evidence that points to N-nitroso compounds and mutagens is compelling, but it’s not enough. “What carries the most weight is not the poten­tial mechanisms but the consistency,” says the American Cancer Society’s Michael Thun.

“The relationship between meat con­sumption and colorectal cancer has been replicated in enough studies and enough different situations that it holds up.”

Other Cancers

Meat mutagens and N-nitroso compounds may damage more than the gut. “In animal models, both HCAs and N-nitroso compounds are multi-site carcinogens,” says the National Cancer Institute’s Amanda Cross. “Once they’re in the blood, there’s no reason they can’t act at any site.” But so far, the evidence for other can­cers isn’t as strong as it is for colorectal.

Here’s a summary of some key cancers:

Prostate. In the Prostate, Lung, Colorec­tal, and Ovarian Cancer Screening Trial, men who averaged at least a third of an ounce of well-done meat a day had a 40% higher risk of prostate cancer than men who ate no well-done meat. And in the Agricultural Health Study, men who ate well-done meat had twice the risk of advanced prostate cancer than men who ate no well-done meat. But overall, most experts are waiting for more evidence. “We’re following up on it,” says Cross.

Pancreas. In an earlier report from the NIH-AARP study, men — but not women — who ate more red meat or more grilled or barbecued meat had a 40-50% higher risk of pancreatic cancer. And in April, researchers reported (but haven’t yet published) data from the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial showing a 60% higher risk in people who preferred well-done steak. “If you could find a risk factor that would reduce your risk by even 20%, that would be a big deal” because pancreatic cancer is so deadly, says the National Cancer Institute’s Arthur Schatzkin. But, he adds, “I don’t think we’re there yet.”

Breast. Studies looking at meat and postmenopausal breast cancer have come up empty. “In two studies that looked at breast cancer, we didn’t see any associa­tion,” says the National Can­cer Institute’s Rashmi Sinha. And a Canadian study of nearly 50,000 women found no link between breast cancer and heme iron. Harvard’s Walter Wil­lett concurs. “Meat consumption was not related to breast cancer in post­menopausal women in our studies.”

However, a link did show up with less common pre­menopausal breast cancer. In the Nurses’ Health Study, women who averaged more than 11/2 serv­ings of red meat a day had twice the risk of estrogen-positive premenopausal breast cancer than women who ate red meat no more than 3 times a week.  “We also saw that meat consumption during high school years is related to risk,” says Willett. But that hasn’t been confirmed, in part because “there’s not another good study in premenopausal women.”

Diabetes

When researchers dug into data from the Women’s Health Study — which monitored more than 37,000 women for roughly 9 years — they found that those who ate processed meat at least 5 times a week had a 38% higher risk of Type 2 diabetes than those who ate pro­cessed meat less than once a week. The most common processed meats: bacon and hot dogs.

“The adverse effect of processed meats shows up repeatedly,” says Willett. “The nitrites may be damaging the islet cells in the pan­creas.” (In Type 2 diabetes, the islet cells continue to secrete insulin, but they can’t keep up with the demand because the body becomes insulin-resistant.)

The Women’s Health Study also found a 28% higher risk of Type 2 diabetes in those who ate the most red meat of any kind. As with colorectal cancer, heme iron may be partly to blame. In the Nurses’ Health Study, women who consumed the most heme iron had a 28% higher risk of diabetes than women who consumed the least. “There’s pretty good evidence that some of the adverse effect of red meat consumption is related to its high iron content, which probably damages the islet cells,” says Willett.

The non-heme iron in grains, beans, and vegetables is not under suspicion. “That’s an im­portant difference because heme iron often gets an A+ because it’s more bioavail­able,” says Willett. But that bioavailability is a double­-edged sword. “The problem with heme iron is that we continue to absorb it even if we don’t need it,” he notes. “It overrides the regulatory mechanisms.” That doesn’t happen with non-heme iron. “If you have adequate iron stores, you won’t absorb non-heme iron very well,” says Willett. “That’s actually good.”

— Source: Nutrition Action, June 2009

Learn 50 reasons why you should eat less meat in the CAP Guide, What's Wrong With Eating meat? and how you can be cancer-free in Prevent Cancer