Written by Cedric F. Garland, Dr. P.H. F.A.C.E.
University of California at San Diego Medical Center
University of California at San Diego Medical Center
Note: References (in parenthesis) are located in the sidebar.
State of the union
Age-adjusted breast cancer incidence rates have tripled in the USA since the mid-1930's. Some of this increase may be due to detecting more cases by mammographic screening, but some is probably real. Either way, it is upsetting for a woman and her family to be told she has breast cancer. The treatments are often painful. The chemotherapy is often nauseating and toxic to heart and lungs.
While incidence rates have gone up, annual age-adjusted breast cancer mortality rates have declined from about 27 per 100,000 in 1930 to about 20 per 100,000 now. That is a little progress, but the USA still has far higher breast cancer death rates than most countries. The decline in mortality may be due to improvements in surgery and post surgical care, and possibly a little due to greater intake of vitamin D in recent years.
If all society does during Breast Cancer Awareness Month is to recommend mammography screening every other year, though, we will sadly continue spinning our wheels for another 50 years in our efforts to defeat breast cancer.
Trying to improve early detection is not the answer. If we make the test more sensitive we will have higher incidence rate of breast cancer each year than we do now.
Primary prevention starts with vitamin D levels
> 40 ng/ml
Where do we go from here? The answer is to place the focus before early detection, on primary prevention of breast cancer. We know that raising the serum 25-hydroxyvitamin D to 50 ng/ml (125 nmol/L) will prevent half of postmenopausal breast cancer(1). This is based on 14 supportive observational studies and a randomized trial in the effective range for vitamin D3.
If every woman maintains a 25-hydroxyvitamin D of 50 ng/ml, incidence of breast cancer will be cut in half. Some might argue that cutting incidence of breast cancer by half is not enough.
50% reduction leads to eradication
This is where the magic of epidemiology enters the picture.
Epidemiology as a science goes back to the venerable Italian epidemiologist, Bernardino Rammazzini (1633-1714), who studied the influence of type of work on risk of disease. There's a long history from which to draw.
Here's the magic. With few exceptions, once humanity has divined enough about the cause of a disease to account for 50% of its incidence, and act upon the knowledge, the disease will soon be defeated.
Table 1 summarizes some diseases where epidemiology determined the cause and allowed action to focus on eradication of the disease.
Once a method is discovered that prevents 50% of a disease, most diseases are defeated, and are usually nearly 100% eradicated within the locale of the discovery. This typically happens within 10-20 years of reaching the 50% point.
It may take hundreds of years to discover how to prevent 50% of a disease. But, after that discovery it takes relatively few years to defeat it. Based on our current data, we're already there!
Age-adjusted breast cancer incidence rates have tripled in the USA since the mid-1930's. Some of this increase may be due to detecting more cases by mammographic screening, but some is probably real. Either way, it is upsetting for a woman and her family to be told she has breast cancer. The treatments are often painful. The chemotherapy is often nauseating and toxic to heart and lungs.
While incidence rates have gone up, annual age-adjusted breast cancer mortality rates have declined from about 27 per 100,000 in 1930 to about 20 per 100,000 now. That is a little progress, but the USA still has far higher breast cancer death rates than most countries. The decline in mortality may be due to improvements in surgery and post surgical care, and possibly a little due to greater intake of vitamin D in recent years.
If all society does during Breast Cancer Awareness Month is to recommend mammography screening every other year, though, we will sadly continue spinning our wheels for another 50 years in our efforts to defeat breast cancer.
Trying to improve early detection is not the answer. If we make the test more sensitive we will have higher incidence rate of breast cancer each year than we do now.
> 40 ng/ml
Where do we go from here? The answer is to place the focus before early detection, on primary prevention of breast cancer. We know that raising the serum 25-hydroxyvitamin D to 50 ng/ml (125 nmol/L) will prevent half of postmenopausal breast cancer(1). This is based on 14 supportive observational studies and a randomized trial in the effective range for vitamin D3.
If every woman maintains a 25-hydroxyvitamin D of 50 ng/ml, incidence of breast cancer will be cut in half. Some might argue that cutting incidence of breast cancer by half is not enough.
50% reduction leads to eradication
This is where the magic of epidemiology enters the picture.
Epidemiology as a science goes back to the venerable Italian epidemiologist, Bernardino Rammazzini (1633-1714), who studied the influence of type of work on risk of disease. There's a long history from which to draw.
Here's the magic. With few exceptions, once humanity has divined enough about the cause of a disease to account for 50% of its incidence, and act upon the knowledge, the disease will soon be defeated.
Table 1 summarizes some diseases where epidemiology determined the cause and allowed action to focus on eradication of the disease.
 |
| Click to Expand |
Once a method is discovered that prevents 50% of a disease, most diseases are defeated, and are usually nearly 100% eradicated within the locale of the discovery. This typically happens within 10-20 years of reaching the 50% point.
It may take hundreds of years to discover how to prevent 50% of a disease. But, after that discovery it takes relatively few years to defeat it. Based on our current data, we're already there!
We'll maybe a little facetiously call the above the "Garland Law of Defeating Disease." This is a general rule, but there are occasional exceptions.
An analogous phenomenon was described by Malcolm Gladwell in The Tipping Point. The idea adapted from Gladwell is that a preventive measure, once discovered, confirmed and clearly described is likely in a position to "go viral". Once enough people implement the preventive measure, induction or disease or death by the causal factor will drop rapidly. Widespread application of the newly-discovered preventive measure will lead to its refinement and result in its greater efficacy. Is vitamin D the tipping point for breast cancer?
For vitamin D, the widespread application - that will lead to widespread implementation, is refinement of the dosage, serum concentration target and form of the vitamin (now known to be vitamin D3, not vitamin D2).
We now believe that a serum 25-hydroxy vitamin D concentration of less than 100 ng/ml is safe, according to research collated by the National Academy of Sciences(2).
A distinguished panel of vitamin D scientists and physicians recommends 40-60 ng/ml as the target for serum 25(OH)D(3). Today we may just have reached the tipping point for eradicating postmenopausal breast cancer. The rapid pathway to its defeat could be stunning.
First vitamin D and cancer research in 1989
The knowledge on vitamin D and cancer has been painstakingly acquired through scientific research starting in approximately 1989 with different studies reporting the link of vitamin D deficiency and cancer.(4,5,6) This research was confirmed by a study at Creighton University by Joan Lappe and associates, including the late Dr. Robert Heaney(7) and a cohort study by Sharon McDonnell and colleagues of the GrassrootsHealth cohort(8).
The refinements are usually adjustment of dose and form of administration of the preventive agent. Historical examples include using citrus fruit to prevent scurvy in sailors, sunlight and vitamin D to prevent rickets, and niacin to prevent pellagra. There are many other examples of an originally approximately 50% effective approach ultimately resulting in eradicating 100% of a disease.
Even vaccines that seem relatively ineffective at first can conquer a disease. The Salk polio vaccine was maybe about 70% effective, but it ended up preventing 100% of polio. The concept is that of a tipping point. That tipping point is historically about 50% effectiveness for most diseases.
We do not always know for sure why this happens but it almost always does. It is probably that the blockage to effective prevention was not knowing the right strategy. Once the strategy is identified, it's usually only a matter of time until the strategy evolves in a way that results in preventing 99-100% of the disease.
Divining the right strategy is the bottleneck. Once past the bottleneck, the journey to 100% eradication is a matter of corrections that require faith in the idea and persistence.
In summary, there is good reason from epidemiological history and specialized knowledge to believe that we are on the threshold of eradicating postmenopausal breast cancer. We need just a little more activism now to make this happen. This will be the start of a golden era of preventing cancer.
Join GrassrootsHealth with its Moving Research into Practice program to help make this happen now.
Join GrassrootsHealth with its Moving Research into Practice program to help make this happen now.
