Anne McTiernan, MD, PhD, of the Fred Hutchinson Cancer Research Center in Seattle, Washington, and author of Starved: a Nutrition Doctor’s Journey from Empty to Full (Central Recovery Press, 2016) talks about a new study showing that diet and exercise may be big factors in determining cancer risk.
Interview conducted by Ivanhoe Broadcast News in December 2016.
Tell us about the latest study and what you found.
Dr. McTiernan: This was a study where we were looking to see if weight loss affects the proteins that are associated with things that can cause tumors to grow. Tumors need nutrition just like other cells and so we wanted to see if these things that are called angiogenesis markers were affected by weight loss. We know that people who are overweight or obese have higher risk of getting cancer and we know that the same people that are overweight or obese also have higher levels of these angiogenesis markers in their blood. Our goal was to see what happens if you get people to lose weight. This was a clinical trial where we randomly assigned people to one of four groups, either to a diet group where they were asked to lose weight -about ten percent of their starting weight over six months, or to an exercise group, or to a combined diet and exercise group, or to a control group. Then we followed them for a year. These were all women; they were postmenopausal women who were either in the overweight or obese category. We were particularly interested in studying these types of women because they’re at increased risks of several cancers especially breast cancer. We wanted to see can we affect these markers of angiogenesis which are things that can promote tumor growth. We found that we saw a significant reduction. We were surprised at how much reduction and the significance of it in these markers – between ten and twenty percent reduction. This is interesting also because nobody had looked at this before. It was really a novel research project and a novel finding.
It’s more than one protein, is it the angiogenesis —
Dr. McTiernan: They were angiogenesis markers. Angio relates to blood vessels and genesis means growth. Tumors tend to make their own blood vessels. That’s what helps them grow. If a tumor has those blood vessels marked off or closed off with some medications, for example, that can stop their growth. But those medications have some adverse effects. We wanted to test a more natural way of reducing the ability of tumors to develop blood vessels.
When you say exercise and eating right what were they doing, is it low carb, is it low cal?
Dr. McTiernan: We gave the women a pretty standard reduced calorie diet. It’s one that’s proven to reduce risk of diseases like diabetes. We asked women to reduce their calories to between twelve hundred and fifteen hundred a day depending on their starting weight. We asked them to reduce their fat intake and that was just as a way of reducing calories. Then we asked them to write down everything they ate which is one of the best ways to lose weight, to know what you’re putting in your mouth. Then the goal was to lose ten percent of their starting weight. We had them work with a nutritionist both individually and in groups. If they were having problems we gave them some extra assistance. If they were in the exercise group, we asked them to exercise for about forty-five minutes a day, five days a week. They exercised three times a week in our facility and two times a week at home. They could use any machines that they wanted but most of the women chose to do walking on a treadmill or walking outside. Then if they were in the combined diet and exercise group, they did both the diet and the exercise programs.
You said it was surprising to you. Are other doctors going to notice this and really start recommending, it’s kind of the old fashioned approach right?
Dr. McTiernan: The paper was published in a major cancer journal so that it got some attention that way, but I think studies like this need to be replicated. It would be really interesting to test the effect of weight loss in cancer patients because cancer patients already have a tumor that has grown. I think we need some further study but there are so many reasons for people to keep their weight down and to lose weight if they’re in the overweight or obese categories. We’ve shown in that same study that reducing weight reduces hormones that can promote tumors’ growth that it reduces inflammation which also promotes tumor growth, and can affect various other things that are causing tumors to either start or to grow. We really see a benefit to weight loss that’s across the board; it can be something that people can do on their own.
Other studies you’ve done that have showed reducing hormones, inflammation as well as diet and exercise can do that naturally versus pills to fight it back. What was the name of that specific study?
Dr. McTiernan: We call it the Nutrition and Exercise for Women Study or the NEW Trial.
What was the journal?
Dr. McTiernan: The [journal that]published the study was called Cancer Research.
Anything else you want to add, it surprises me in terms of weight reduction that’s doable.
Dr. McTiernan: Yes, ten percent. It’s never easy to lose weight but ten percent is something that people can do. If you were two hundred pounds to start with that means losing about twenty pounds. But you don’t need to be a biggest loser in order to see incredible health benefits from weight loss.
END OF INTERVIEW
This information is intended for additional research purposes only. It is not to be used as a prescription or advice from Ivanhoe Broadcast News, Inc. or any medical professional interviewed. Ivanhoe Broadcast News, Inc. assumes no responsibility for the depth or accuracy of physician statements. Procedures or medicines apply to different people and medical factors; always consult your physician on medical matters.
If you would like more information, please contact:
Jennifer Connor
206-667-7979
Sign up for a free weekly e-mail on Medical Breakthroughs called First to Know by clicking here.
