a special program of the National Emergency Medicine Association (NEMA)

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Week: 589.7 Pt.1 

Guest: Dr. Delprit Bagga, researcher, UCLA Jonsson Cancer Center 

Topic: Breast cancer/oil study 

Host/Producer: Steve Girard 

NEMA: We’re all interested in lowering our risk of cancer...and reducing our fat intake seems to play a role. A study from UCLA’s Jonsson Cancer Center concentrated on it’s role in breast cancer....we’re with Dr. Delprit Bagga, lead author of the study paper appearing in the Journal of the National Cancer Institute...  

BAGGA: When you look at the literature, in diet and chronic diseases like cancer, one sees a clear correlation between fat intake and incidence of cancer. So, when you compare countries where the intake of dietary fat is relatively low, like Japan, compared to countries like the U.S., where the total fat intake is very high, one clearly sees a difference in cancer incidence. And one could speculate that fat in the diet could be making some difference...and based upon that hypothesis, we decided to intervene in breast cancer patients with a diet which is very low in fat, and we decided to supplement the diet with fish oil, which is very high in omega-3 fatty acids...and soy supplements. And again, these two supplements we used because when you compare the diets of countries where the incidence is very low, again, like Japan... when yo compare the diet, they have a very high intake of omega-3 fatty acids, because of their high consumption of fish and seafood, and they also consume a lot of soy. Whereas the American diet is deficient in these components....apart from being high in fat. So, that’s why we decided to use such a diet, which would be low in fat and high in omega-3 fatty acids, and soy supplements.  

NEMA: Explain the difference between the omega-3 and omega-6 fatty acids...  

BAGGA: Both these families...the omega-3 and omega-6 families of fatty acids...both these are polyunsaturated fatty acids. The difference between these is the kind of fatty acids and how they affect health. The omega-3 fatty acids are predominantly in fish and seafood...they have been shown, at least in the animal experiments and the cell culture studies...they have been shown to inhibit the growth of tumors. On the other hand, the omega-6 family of fatty acids, which are predominantly in corn oil and some other vegetable oils...they tend to promote the growth of cancer cells. Again, that’s experimental evidence. Clinically, whether this story will still hold...that’s what we are testing. Our main aim is to see if we can change the ratio of these two families of fatty acids in the diet, and how they would affect conditions like cancer...especially breast cancer.  

NEMA: Tell me about the study...who made up the population for it...and how did you proceed?  

BAGGA: We studied women who had had treatment for breast cancer...but they had all suffered from advanced breast cancer...that is, stage two and three breast cancer. And we put them on a very low fat diet...which was basically 15% of the calories coming from fat...along with fish oil and soy supplements, for three months. And these women were followed closely, and we studied their, the composition of breast fat in terms of fatty acid composition...whether we could change the ration of different fatty acids in the breast ffat, and what implications that changed ration would have in terms of cancer prevention. So, basically, they were all women who’d had treatment for breast cancer, and they were all in remission when they entered this study.  

NEMA: How long did you follow the participants....and what did you discover?  

BAGGA: The three month intervention...what we basically found was that diet could affect the environment within the breast...that means when we looked at the ratios of the different fatty acids in the breast fat , we could change those in three months be using a specific diet. And this was really encouraging, because nobody was really shown that in such a short time, you can actually make a significant difference in the fatty acids. So, if you can change the environment within the breast, I think that would be very important, because that means you can target the breast itself and in the long run, what that effect would be...would be important to study.  

NEMA: I noticed that the breast fatty tissue seems to be more sensitive to the change in oils in the diet...why is that?  

BAGGA: One could speculate that there is some metabolic difference between the breast fat compared to the fat in other parts of the body. Because in our study, we did compare the breast fat as compared to the gluteal fat, or the buttocks fat. And we saw that within three months, the changes we observed in breast fat were much more significant than the changes that we observed in the buttocks fat. So, basically one could speculate that the buttock fat is basicallymore inert...it’s less metabolically active, that means. The turnover in whatever is stored in the buttock fat is much slower, as compared to the upper body, or the breast fat. And there have been a few studies that have shown that the upper body fat, or adipose tissue, is different when compared to the lower body adipose tissue...or the fat tissue.  

NEMA: Considering the good results of this study...what’s next? What areas does this infomation bridge towards?  

BAGGA: So, this study has basically shown that diet can change the environment in the breast. Now the next step...what we are studying now is whatever changes we’ve observed in the breast tissue of these women...we’re going to see how this affects the growth of cancer cells. So, we’re going to incubate some cancer cells in the ratios that we’ve observed within the breasts of these women, and then see if we can inhibit the growth of cancer cells. And then, the other thing that we want to study is...whether whatever these changes that we’ve observed...can they be maintained long term....so a new group of women will be studied, and they’ll be followed up for a much longer time. Because right now, the study was only for three months, so the future patients will be followed for a much longer time...maybe six months to one year, see if we can maintain these changes...or if the changes increase further with passage of time...you know, if they stay on this diet for another three months...for a total of six months...do we observe more changes? Or do the changes stabilize in six months. So, all that is still under study, and then we would be able to tell much better what the implications of the results would be.  

NEMA: Do Asian families use fish oil as a product with other foods in cooking? Or is it only available in fish and seafood?  

BAGGA: We gave them fish oil capsules, so they were concentrated source of omega - 3 fatty acids. So, the alternative to that is eating certain kinds of fish, which are high in omega-3 fatty acids. And these are the only two sources of the fatty acids which would make a difference. You can’t cook in fish oil...so it’s not like corn oil, or olive oil that you can use for cooking....cause it’s a very long chain fatty acid, and if you heat them, they become succeptible to degradation very easily. So I guess eating fish is the only alternative to taking capsules.  

NEMA: And taking in fewer fat calories....of the omega-6 variety...  

BAGGA: The emphasis should be that people need to eat a low fat diet...it’s not only the quality of fat, but also the quantity that needs to be lowered, so the bottom line is eat a low fat diet, and then probably incorporate omega-3 fatty acids in the diet by eating fish.  

NEMA: Dr. Delprit Bagga, of the UCLA Jonsson Cancer Center in California.