Carcinogens in foods

You may wonder why there are carcinogens present in our food. Actually there are three different sources of carcinogens in our food The first, they are naturally occurring in the food. And secondly, they may be generated during the cooking processes And thirdly, they may produced during improper storage. So I’m going to give you examples of each cases. The first, there are carcinogens present naturally in our food. One of the examples is safrole. What is safrole? it is a compound found in lots of herbs such as nutmeg, cinnamon or basil. In addition, it is also found in betel pepper when we eat the betel nuts. And you may wonder how it works? Actually it is defined as a carcinogen from animal experiments.

In the past when the scientists gave 0.5% safrole containing diet to animals and after feeding for nine months, half of the animals have gotten cancers. Therefore the safrole was defined as a carcinogen so can we still eat nutmeg, cinnamon, basil Of course, cause from the animal experiments, the animals were fed with purified safrole every day with high dose. And the safrole, the amount of safrole present in the natural food is not that high So although it is defined as carcinogens but from our ordinary diet you should be okay. The second source of carcinogens in our diet is they may be generated during cooking processes. From lots of cooking processes, including heating, some of the carcinogens may be generated.

One of them is polycyclic cyclic aromatic hydrocarbons, we abbreviate it as PAH. And it is from incomplete combustion of carbon containing compounds So from barbecue, from smoked foods, we may found PAH in this kind of foods. And thirdly, the carcinogens may be generated during improper storage. As we know if the food is stored improperly, some microorganisms will be grown. One of the examples is the fungi, Aspergillus species. They can grow under high humanity and the proper temperature environment. Once they grow, they can produce some toxins including aflatoxin B1 And aflatoxin B1 has been found as a potent carcinogen especially for liver cancer. And aflatoxin B1 can be found in molded peanuts, greens, corns, or even wine.

And the second category is there are substances found in diet may affect carcinogen formation. And from this category, we can divided into three different sub groups. First of all, the diet components may provide as a substrate for carcinogen formation. And the secondly, the diet component may alter bile acids excretion or by bacterial flora in our gut. And thirdly the diet composition may alter carcinogen concentrations in feces. So let’s talk about the substrate of the carcinogen formation I’m sure most of you have heard about nitrite or nitrate in our food. Nitrite is you used as a food additives to preserve the meat So nitrite is found in lots of processed meat including ham, sausage. And the other type is nitrate.

Nitrate is an essential compound for lots of plants, so we we may also find nitrate in vegetables. Lots of nitrate can be converted to nitrate and nitrite under the acidic conditions such as in our stomach can interact with the secondary or tertiary amines to generate nitrosamine. And the nitrosamine is also a carcinogen So nitrite although it is used as food additives, it can be also a substrate for nitrosamine formation. And the second type, the FAT. FAT or lipid is one kind of essential nutrients for us but if we consume too too much fat they can increase the secondary bile acids in our gut or in our intestine.

And the secondary bile acid can act as a tumor promoter because the secondary bile acids can alter chemical reactions or the bacteria microflora in our gut So that the presence of high concentrations of secondary bile acid can increase the carcinogen production in our intestine So that, it increases the Colorectal cancer incidence. On the contrary to high-fat diet and the dietary fiber has a reverse reaction. The dietary fiber can also alter the micro bacteria micro flora in our gut but it decreases the carcinogen formation environment. So dietary Fiber has a protective effect on colorectal cancers. The third, the components from our diet can alter carcinogen concentrations in feces. The the most well-known example is dietary fiber.

As we all know that if we increase the consumption of dietary fibers, it can increases the fecal bulk. Once the fecal bulk is increased, the existing carcinogen in the feces can be diluted so that the chances of carcinogen to contact with the intestine cell will decrease. On the other hand, as we increase the fiber consumption, it can increase the transit time of the feces in our gut. so that it also decrease the chances of the carcinogen to contact with the intestinal cells. so that to increase the dietary fibers may decrease the risk of colorectal cancers.