Interview with CHE Partner, William B. Grant, PhD, President, Sunlight, Nutrition, and Health Research Center

During this project, I developed a familiarity with the ecologic approach. In this approach, populations defined geographically are the entities, and both disease outcomes and risk-modifying factors are averaged at the population level. When I read in late 1996 that Japanese men in Hawaii had 2.5 times the risk of developing Alzheimer’s disease (AD) than native Japanese, I made the connection between acid rain and AD and increased uptake of aluminum by trees and humans, and hypothesized that dietary factors played a very important role in the etiology of AD.

Following the footsteps of Bruce Armstrong and Richard Doll, I obtained the AD prevalence data for 11 countries along with the dietary supply data and compared them in a statistics package. I quickly determined that total energy (calories) and total fat were primary risk factors, while fish and cereals/grains were risk reduction factors. This paper was published in Alzheimer’s Disease Review on June 17, 1997 and I held a press conference at the National Press Club in DC to announce the findings. Both Dan Rather and CNN covered the story. The results were confirmed in 2002 and 2003 in case-control studies. Buoyed by quick success in a new field, I set about to study dietary and environmental risks for other diseases including coronary heart disease and cancer. That eventually led to my current primary interest of studying the role of solar ultraviolet-B (UVB) and vitamin D in reducing the risk of cancer and other diseases.


What is your primary mission in your work?

The primary mission in my work is to identify and quantify risk-modifying factors for chronic diseases. I am particularly interested in UVB and cancer, but have also studied dietary factors. I have a background in environmental issues, and am trying to find data to use to identify roles of environmental pollutants in disease risk as well.


What are the most important recent developments in your work, scientific or otherwise?

Since I began my work on UVB/vitamin D and cancer around 2000, the list of vitamin D-sensitive cancers has grown from 4 to somewhere between 20 and 27. My findings interested Harvard University in including solar UVB in their cohort studies, and the findings by Edward Giovannucci and coworkers have done much to convince many others that vitamin D is very important for cancer and other diseases. During 2006, the health community seems to have awaken to the fact that vitamin D is required for optimal health, and that between 1000 and 2000 I.U. of vitamin D3 per day is indicated.


What successes have most encouraged you in your work recently?

Continued research showing that vitamin D is important for optimal health and increased awareness by policy makers. The American Cancer Society finally added vitamin D to its list of cancer reducing dietary components in 2006.


What have been some of the greatest recent challenges?

Overcoming the reluctance of dermatologists to admit that solar UVB is the primary source of vitamin D for most humans, and that if they counsel to reduce solar UV irradiance, they should mention that 1000-2000 I.U. of vitamin D/day is required for optimal health and if they don’t get it from solar UVB, they have to get it from supplements or fortified food. I just published a paper on cancer mortality rates in Spain where I was able to show that mortality rates for 17 types of cancer were inversely correlated with non-melanoma skin cancer. Melanoma was one of them, and others have shown that vitamin D reduces the risk of melanoma. The primary risk factor for melanoma is the longer-wave UV, called UVA, and sunscreen sold in the U.S. does not protect adequately against UVA.

The other challenge is to get policy makers to accept the findings of ecologic studies. Richard Doll and Richard Peto essentially dismissed the ecologic approach as being useful only for developing hypotheses in their 1981 paper on cancer in the U.S. and the health community followed suit. What they don’t realize is that many important findings regarding disease risk have been identified and even well quantified using the ecologic approach, often years before standard epidemiologic approaches can confirm the findings. They also seem not to realize that multicountry studies have much larger dietary variations than single-country cohort studies, so are better able to determine risks related to dietary factors elevated but common in Western Developed Countries.


What would you regard as the most significant potential future developments in your field?

To solidify the UVB/vitamin D/cancer theory, the policy makers desire successful prospective studies. The recent Women’s Health Initiative study on calcium and vitamin D supplementation failed in this regard because only 400 I.U./day was used. However, those who had higher intakes of vitamin D prior to the beginning of the study had a 40% reduced risk of developing colorectal cancer. However, they are beginning to accept the ecologic study findings since they have been replicated so many times recently, and vitamin D has few adverse side effects.

What I would like very much to see is vitamin D3 being used in conjunction with other modalities to treat those diagnosed with cancer. Starting in 2004, papers have reported that cancer survival in Norway, the U.S., and England depends on season of diagnosis, with those diagnosed in summer or fall having 10-50% greater 18 month to 5-year survival rates.


What or who continues to inspire you in your work?

I am motivated by being able to use my scientific abilities to make important findings regarding human health and seeing my results used by others in their research programs or policy decisions. I am also motivated by the desire to help people realize that being healthy is up to them and not our disease treatment system, which makes more money off of illness than wellness.


Do you have any comments/suggestions regarding CHE itself?

Just that in looking for effects of environmental contaminants in cancer other factors should be included in the analysis. In my latest paper on cancer mortality rates in the U.S., I included alcohol consumption, ethnic background, poverty, smoking, urban residence, and solar UVB. This analysis actually led to finding more UVB-sensitive cancers than my earlier study using only UVB. I found one region of the country in the Atlas of Cancer Mortality in the United States, 1950-94 that I can attribute to environmental pollution – southeast Louisiana. It appears that chemical factory emissions get into the Mississippi River. When the river water is treated with chlorine for drinking, chlorinated hydrocarbons are created. Those who drink well water in Louisiana have much less cancer than those drinking treated river water.

Find out more about Dr. Grant's work at: http://www.sunarc.org/.

 
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Posted: 10 January 2007