Processed meats are known to cause cancer. The World Health Organisation, has placed processed meats in the risk category of other known toxins such as asbestos, arsenic, alcohol and tobacco! The World Cancer Research Fund International (www.wcrf.org) looked at about 7000 studies showing the link between diet and cancer. They concluded that these processed meats are unhealthy and are major contributors of cancer. The meat contains various chemicals and additives that cause this unhealthy effect.
This brings us to the question, what is processed meat?
Processing for preservation includes using methods like curing, salting, canning, smoking and drying. Meats like sausages, salami, bacon, pepperoni and hot dogs are classified as processed. The preservation techniques are meant to extend shelf life, but the chemicals involved could increase the risk of cancer. In addition, the high temperatures used in certain cooking methods like grilling and barbequing could further increase this effect. In addition, consumption of processed meat has been linked with unhealthy eating habits. This means that vegetable and fruit consumption is low. The antioxidants in fruits and vegetables if eaten offer protective effects.
Let’s take a look at what are the drawbacks of regular consumption of these meats and how they increase cancer risk.
1. Unhealthy preservatives
Processed meat contains compounds such as N- Nitroso, nitrite and nitrosamines. Sodium nitrite is used to preserve the colour of the meat and to supress the fats from becoming rancid- thereby leading to spoilage. They also act as a preservative and prevent the growth of bacteria which could cause food poisoning. These preservatives form nitrosamine which increases the risk of developing cancer.
2. High heat cooking is harmful
Nitrosamines are formed when meat is exposed to high temperatures above 130 degrees centigrade. This is why cooking using high heat methods is not advisable. High temperature cooking also releases Heterocyclic Amines or HCA’s. They are known to cause colon, breast and prostate cancer. Lean meats are also prone to form HCA when cooked at high temperatures. Alternate cooking methods like boiling, poaching or low heat pan searing/ frying can help lower this risk.
3. Preservation by smoking
Smoking is a commonly used method to preserve meat. However, this tends to release harmful substances called polycyclic aromatic hydrocarbons or PAH’s. These particulates settle over the meat when it is cooked/ cured over an open fire. The fat drippings from the meat on exposure to smoke can also form these harmful compounds. These chemical contaminants are known to cause breast, colorectal, prostate and pancreatic cancer.
4. Salt is a commonly used meat preservative.
Processed meats usually contain high amounts of salt. This also helps to improve on taste. While it is known that salt increases the risk for high blood pressure, stroke and cardio vascular incidents, some studies have reported a link between a high salt diet and stomach cancer. This is due to the increase of a bacteria called Helicobacter pylori, which leads to the formation of stomach ulcers.
For those who consume processed meats frequently, it is advisable to cut down and replace these with healthier alternatives. Chicken and fish with the skin removed and eggs are good sources of animal protein. Red meat can be taken in limited amounts and should be cooked using healthy cooking methods over low heat.
It would also help to:
• Read and understand food labels
• Avoid meat with sodium nitrite or monosodium glutamate (MSG)
• Include fresh fruit and vegetables with meals
• Opt for healthier sources of protein and include vegetarian protein like soy and its products, daals, legumes and pulses.
Does red meat have any importance in the diet?
It is important to follow a balanced diet. Red meat contains nutrients such as iron, zinc and protein. This can be included along with the healthier sources of protein. Moderation is important. A palm sized serving once in a month will not harm you. But consumption on a daily basis poses serious health risks. Freshly ground red meat or sliced meat do not come under the processed meat category. Healthy living includes moderation and enables us to live happy and healthy lives.
With inputs from:
2. Meat consumption patterns and preparation, genetic variants of metabolic enzymes, and their association with rectal cancer in men and women. Murtaugh MA1, Ma KN, Sweeney C, Caan BJ, Slattery ML. J Nutr. 2004 Apr;134(4):776-84.
3. Effect of cooking temperature on the formation of heterocyclic amines in fried meat products and pan residues. Skog K, Steineck G, Augustsson K, Jägerstad M. Carcinogenesis. 1995 Apr;16(4):861-7.