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Author: Sima

Published on Leave a comment on Best to Eat Calcium Rich Foods, Not Calcium Supplements

Once again, a study found an association between a worrisome health problem (intestinal polyps) with a dietary supplement (calcium), but no problems with eating the foods (calcium rich foods). The large multi-center study specifically looked at serrated polyps (SPs) because they are considered precursor lesions for colorectal cancer - that is, that while they are not cancerous, some of them will develop into cancer. Persons invited to join the study had a recent colonoscopy with at least one adenomatous polyp detected and removed, and then were scheduled for another colonoscopy 3 to 5 years later. This was considered a "chemoprevention study" to see if certain supplements help prevent polyps (and thus cancer).

People in different parts of the US were randomly assigned to either receive calcium supplements (1200 mg/day of elemental calcium), vitamin D (1000 IU/day of vitamin D3),  both supplements (calcium supplement plus vitamin D), or neither. Supplement treatment continued for 3 to 5 years and then there was an observational period that was 6 to 10 years after the person first started supplementation. The higher incidence of serrated polyps was a "late effect" (6 to 10 years later) and not seen during the treatment time (the first 3 to 5 years). They found that women and current smokers had higher risks of serrated polyps when exposed to supplemental calcium. Vitamin D alone was not linked with polyps.

Other studies have also found an association between calcium supplements and increased risk of certain health problems, and a lower incidence of polyps with a higher intake of dietary calcium (real food). The researchers said: "Patients with a history of premalignant serrated polyps, especially women and smokers, may wish to avoid vitamin D and calcium supplementation." BOTTOM LINE: General guidelines should be to eat foods, not supplements, to get your nutrients, vitamins, and minerals. There are many studies also at this point that a high fiber diet with lots of fruits, vegetables, whole grains, legumes (beans), nuts, seeds are associated with better intestinal health and fewer polyps (here, here). Another way to view it is: feed your beneficial gut microbes with good, real food. And especially not highly processed junk. From Medical Xpress:

Calcium supplements may boost risk of abnormal bowel growths

Calcium supplements, taken with or without vitamin D, may increase the risk of small growths in the large bowel (colon) called polyps, suggest results from a large US trial published online in the journal Gut. Polyps are small growths in the lower part of the large bowel. They are non-cancerous, but some could eventually turn into cancer if they are not removed. Polyps come in different shapes and sizes, and this study specifically focused on the risk of serrated polyps, which are less common than conventional "adenomatous" polyps, but likely have the same risk of developing into cancer. 

...continue reading "Best to Eat Calcium Rich Foods, Not Calcium Supplements"

Published on Leave a comment on Can We Avoid the Endocrine Disruptors Around Us?

Today I am posting the story of one person writing about how hard it is to reduce contaminants, that is, unwanted chemicals, in our bodies. The story is by Nicholas Kristof, who has been eating organic foods and trying his best to avoid endocrine (hormone) disrupting chemicals (such as BPA) for a number of years. But the analysis of his urine showed that he wasn't able to totally avoid them.

This also raises the question - how many more unwanted chemicals would have been in his body if he hadn't been so diligently trying to avoid them? And as usual, the question remains - what are all these chemical mixtures doing to him and to us? How about developing fetuses and children? To men and women trying to conceive a baby? To the ill and elderly? Right now an experiment is going on in the world, one which we can't escape - chemicals, including endocrine disruptors (all produced by the chemical industry) are being tested on us (the research subjects). For more information on this topic, click on category ENDOCRINE DISRUPTORS and scroll through the posts, or go to Environmental Working Group - ewg.org, or get a Detox Me Action Kit from the Silent Spring Institute (and get your urine analyzed).  Excerpts from the article by Nicholas Kristof, from the NY Times:

What Poisons Are In Your Body?

Our bodies are full of poisons from products we use every day. I know – I’ve had my urine tested for them. But before I get into all that, let’s do a quick check for poisons that might be in your body. 

...continue reading "Can We Avoid the Endocrine Disruptors Around Us?"

Published on Leave a comment on Heavy Drinking And Risk of Dementia

Study after study has found negative health effects from frequent heavy drinking of alcohol, including a number of cancers. On the other hand, light to moderate drinking seems to have some health benefits (here and here). Recently a large study conducted in France found that chronic heavy drinking, which has resulted in alcohol use disorders (alcohol abuse, alcohol dependence, or alcoholism), is the biggest risk factor for developing dementia, especially early onset dementia. Only people with alcohol use disorders which resulted in them being hospitalized were included in the study.

But the surprising thing was that lower levels of "chronic heavy drinking" doesn't seem so much - it's daily consumption of more than 60 grams of pure alcohol  for men, and more than 40 grams of pure alcohol for women. In the United States, a standard drink contains about 14 grams of alcohol - which is a 12 ounce (350 ml) glass of beer, a 5 ounce (150 ml) glass of 12% wine, or a 1.5 ounce (44 ml) glass of spirits. In other words, drinking 3 glasses of wine daily (or more) is heavy drinking for a woman. (Note: The Centers for Disease Control (CDC) views moderate drinking as 1 glass of wine daily for women, and 2 glasses of wine daily for men).  ...continue reading "Heavy Drinking And Risk of Dementia"

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Published on 4 Comments on Common Medicines That Disrupt the Normal Gut Microbiome

Research has found that antibiotics disrupt a person's normal gut microbiome (microbial community), especially because the antibiotics kill both bad (pathogenic) and beneficial bacteria. But what about other medicines? Do they also have an effect?

A recently published study that reviewed the research looked precisely at that topic and found that YES - other medicines (besides antibiotics) also have an effect on (disrupt) the gut microbiome. The different categories of drugs - proton pump inhibitors (PPIs), metformin, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, statins and antipsychotics - all had different kinds of impacts on the gut microbiome.

The researchers also suggest that other types of commonly prescribed medicines now need to be examined for their impact on the intestinal (gut) microbiome, such as thyroid hormones, contraceptive drugs, and antihypertensive (high blood pressure) drugs. Excerpts from Dr. Paul Enck's article about the study at Gut Microbiota Research and Practice:

A systematic review explores the role of non-antibiotic prescription drugs in gut microbiota dysbiosis

Both diet and medications are among the strongest variables affecting the gut microbiome. When it comes to medications, although antibiotics have been repeatedly shown to affect the human gut microbiome, little is known regarding the impact of non-antibiotic prescription drugs on the gut microbiome.

A review, led by Dr. Emmanuel Montassier from the MiHAR Lab at Institut de Recherche en Santé 2, Université de Nantes (Nantes, France), has concluded that some non-antibiotic prescription drugs have a notable impact on the gut microbiome to the same extent as antibiotics.  ...continue reading "Common Medicines That Disrupt the Normal Gut Microbiome"

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Published on 2 Comments on Five Years of Sinusitis Treatment Success

It's official. This month is 5 whole years being free of chronic sinusitis and off all antibiotics! Yes, that's correct - 5 whole years for all 4 family members, and our sinuses feel great!

Back in February 2013 - first I, and then the rest of my family, started using easy do-it-yourself sinusitis treatments containing the probiotic (beneficial bacteria) Lactobacillus sakei. Now we only treat with a L. sakei  product when occasionally needed - and it still works great. In fact, the best way to use Lactobacillus sakei is to use only when there are sinusitis symptoms, and not when feeling well. The whole process still feels miraculous.

After reading the original ground-breaking research on sinusitis done by Abreu et al (2012), it led to me trying L. sakei as a sinusitis treatment. Of course, there is an entire community of microbes (bacteria, fungi, viruses) that live in healthy sinuses - the sinus microbiome - but L. sakei seems to be a key one for sinus health. Since that original 2012 study, other studies have also found that in people with chronic sinusitis, the sinus microbial community is out of whack (dysbiosis). 

The one thing different this past year is that our sinus microbial community (sinus microbiome) seems better. If we need to treat (for example, after a virus that goes into sinusitis, or when sliding toward sinusitis for whatever reason), then all four of us noticed that we need to use much less of a product than in the past. Incredibly little. So it seems that our sinus microbial community has definitely improved over time.

The post The One Probiotic That Treats Sinusitis (originally posted January 2015 and with many updates since then) contains information using my family's experiences (lots of self-experimentation!) and all the information that people have given me over the years. Thanks everyone! The post has a list of brands and products with L. sakei, treatment results, as well as information about some other promising probiotics (beneficial bacteria).

Thank you all who have contacted me  - whether publicly or privately. Please keep writing and tell me what has worked or hasn't worked for you as a sinusitis treatment. If you find another bacteria or microbe or product that works for you - please let me know. It all adds to the sinusitis treatment knowledge base. I will keep posting updates. 

(NOTE: I wrote our background story - Sinusitis Treatment Story back in December 2013, there is a  Sinusitis Treatment Summary page with the various treatment methods quickly discussed, and the latest information on The Best Probiotic For Sinus Infections. One can also click on SINUSITIS under CATEGORIES to see more posts about what is going on in the world of sinusitis research.)

Published on Leave a comment on Eating Yogurt Associated With Lower Risk of Heart Attack and Stroke

Another study finding health benefits from eating yogurt - that men and women with hypertension who eat at least 2 servings or more per week of yogurt were at a lower risk of having a heart attack (myocardial infarction) and stroke. Women also had a lower risk of a revascularization procedure (such as a coronary artery bypass). The strongest association between yogurt consumption and lower risk of cardiovascular disease was among those with higher DASH (Dietary Approaches to Stop Hypertension) diet scores.The DASH diet is considered a healthy diet, one rich in fruits, vegetables, nuts, whole grains, beans (legumes), etc.

The major thing to keep in mind is that high blood pressure is a major cardiovascular disease risk factor. So anything that helps lower risk of heart attack or stroke is good. Note that in this large study they did not randomly assign people to different groups - so the higher yogurt intake people also tended to have a healthier lifestyle. But other studies have had similar findings to this one. For example, eating dairy products regularly is linked to lower rates of cardiovascular disease and high blood pressure, while eating yogurt regularly is linked to lower rates of hypertension and type 2 diabetes.

Also note that the types of yogurt (whole-fat, low-fat, non-fat) eaten were not looked at, as well as the types of probiotics added to yogurts. Some research suggests that beneficial effects are from whole fat dairy products rather than low-fat dairy products - which is different than DASH diet recommendations. From Science Daily:

Eating yogurt may reduce cardiovascular disease risk

A new study in the American Journal of Hypertension, published by Oxford University Press, suggests that higher yogurt intake is associated with lower cardiovascular disease risk among hypertensive men and women. .... High blood pressure affects about one billion people worldwide but may also be a major cause of cardiovascular health problems. Higher dairy consumption has been associated with beneficial effects on cardiovascular disease-related comorbidities such as hypertension, type 2 diabetes, and insulin resistance.

For the current analyses, participants included over 55,000 women (ages 30-55) with high blood pressure from the Nurses' Health Study and 18,000 men (ages 40-75) who participated in the Health Professionals Follow-Up Study.

Higher intakes of yogurt were associated with a 30 percent reduction in risk of myocardial infarction among the Nurses' Health Study women and a 19 percent reduction in the Health Professionals Follow-Up Study men. There were 3,300 and 2,148 total cardiovascular disease cases (myocardial infarction, stroke, and revascularization) in the Nurses' Health Study and the Health Professionals Follow-Up Study, respectively. Higher yogurt intake in women was associated with a 16 percent lower risk of undergoing revascularization.

In both groups, participants consuming more than two servings a week of yogurt had an approximately 20 percent lower risks of major coronary heart disease or stroke during the follow-up period. When revascularization was added to the total cardiovascular disease outcome variable, the risk estimates were reduced for both men and women, but remained significant. Higher yogurt intake in combination with an overall heart-healthy diet was associated with greater reductions in cardiovascular disease risk among hypertensive men and women.  [Original study.]

Published on Leave a comment on Viewing Cancers As Birds, Rabbits, and Turtles

This article by academic physician and cancer researcher H. Gilbert Welch about viewing cancers as a barnyard pen of animals (birds, rabbits, and turtles) is a way to explain why some early screening tests haven't really reduced the rate of deaths from certain cancers, such as breast cancer (here and here). Or another way of looking at it is that some cancers are really "bad" and aggressive (birds that have already flown away to distant points at earliest cancer diagnosis), while others are "good" (rabbits or cancers that are slowly spreading and that can be treated, or turtles - that are such slow growing cancers that they would never cause a problem).

Interesting and thought-provoking reading. Excerpts from an editorial by H.Gilbert Welch from Breast Cancer Research and Treatment:

The heterogeneity of cancer

Cancer used to be so simple. It started as a wayward cell that then underwent a stepwise progression: from in situ to local, local to regional and, finally, regional to distant disease. At least, that is what I was taught in medical school…some (gulp) 40 years ago. Narod and Sopik suggest a wildly different paradigm. Local growth and distant metastasis are independent phenomena. Local control of cancer (e.g., efforts to minimize local recurrence) has no effect on its tendency to metastasize. If a cancer is destined to spread to distant sites, it will have already done so.

Call it the “bad cancers are bad” model. Or, alternatively, “good cancers are good.” Oddly enough, in 1955 a cancer surgeon at the Cleveland clinic—George Crile Jr.—foretold this complexity on the pages of Life magazine: In clinical practice to say that a person has cancer gives as little information about the possible course of his disease as to say that he has an infection. There are dangerous infections that may be fatal and there are harmless infections that are self-limited or may disappear. The same is true of cancers. Cancer is not a single entity. It is a broad spectrum of diseases related to each other only in name. 

..... The conventional model has been that large tumors are more likely to metastasize because they have a large pool of cancer cells to disseminate. Narod and Sopik instead suggest that these tumors became large because they are more aggressive cancers and thus are more likely to metastasize. Large, late-stage, node positive lesions are simply valuable markers for “badness.” The corollary is that small, early-stage, node negative lesions are valuable markers for “goodness.” But not always.

Which brings us to the conundrum of DCIS. It would be simplest if all DCIS was pseudodisease— cancer not destined to ever cause problems for our patients. Most DCIS is pseudodisease, but as Narod documented in earlier work , about 3% of women with DCIS will die from breast cancer in the next 20 years. Over half of these women did not experience an in-breast invasive recurrence prior to death. In other words, bad breast cancers are bad—from the get go.

This phenomenon explains the limited ability of mammography to reduce breast cancer mortality. The lack of value in finding microscopic breast cancers (like DCIS) is one of the least well-recognized findings from the ten randomized trials of mammography. Only one trial addressed this important question, the second Canadian trial ..... Given the finding of no difference in breast cancer mortality between the two groups, the lesson is clear: there is no obvious value to finding breast cancers that are so small they cannot be felt (such as most DCIS).

Overdiagnosis is made possible by cancers at the other end of the spectrum. Overdiagnosis is the detection of cancers that are very good – so good that patients would be better of not having them detected. Overdiagnosis doesn’t limit the ability of mammography to reduce breast cancer mortality—instead it’s a side-effect of the effort.

Such heterogeneity in cancer poses huge challenges for our effort to catch the disease early. It’s been described as the “barnyard pen of cancers” (an analogy that likely originates with Crile). We are trying to catch birds, rabbits, and turtles.

We can’t catch the birds early, because they have already gone—these are the most aggressive cancers, those that have already spread by the time they are detectable. We are able to catch the rabbits—the more slowly progressive cancers— but their earlier detection may not help much, because they weren’t destined to metastasize anyway. And then there are the turtles. There’s no need catch them, because they’re not going anywhere anyway.

Published on Leave a comment on Too Much Cancer Screening Has Misled Us About Risk Factors?

H. Gilbert Welch has written extensively about the issue of "overdiagnosis" and resulting  "overtreatment" of cancers. Cancer screening can cause the problem of overdiagnosis (finding small tumors that may never cause problems) and lead to overtreatment (treating unnecessarily, which can cause harm).

But now Welch and coauthor Otis Brawley discuss the issue of how too much screening and diagnostic testing of people thought to be "high risk"  for certain cancers results in more being found - thus the risk factors are "self-fulfilling". And it occurs the most in "scrutiny dependent cancers" - which are cancers that the more you look, the more you find, and the more of what you find is harmless. Many are referred to as slow-growing, indolent, subclinical, or even as precancerous. Prostate cancer, thyroid cancer, breast cancer, melanoma, and  lung cancer are  examples of "scrutiny-dependent" cancers.

Looking so hard and then finding cancer gives a false impression of an increased incidence of some cancers. The authors also said that risk factors in determining  who should be screened should not be cancer diagnosis (e.g. in a family member), but death from cancer. From STAT News:

Too much screening has misled us about real cancer risk factors, experts say

The best-known downside of cancer screening, such as PSA tests for prostate cancer and mammograms for breast cancer, is that they often flag cancers that pose no risk, leading to overdiagnosis and unnecessary, even harmful, treatment. But widespread screening for “scrutiny-dependent” cancers — those for which the harder you look the more you find, and the more of what you find is harmless — causes another problem, two leading cancer experts argue in a paper published on Monday: increasing the apparent incidence of some cancers. That in turn is misleading doctors and the public about what increases people’s risk of developing cancers — or at least the types of cancer that matter.

“Detecting cancers that would never become apparent is screwing up our understanding of risk factors,” said Dr. H. Gilbert Welch of the Dartmouth Institute for Health Policy and Clinical Practice, co-author of the analysis in Annals of Internal Medicine. The problem is especially clear in prostate, breast, and thyroid cancers, all of which are scrutiny dependent.

Men whose relatives developed prostate cancer are more likely to get PSA and other screening tests, either because they request them or because their physicians, noting their family histories, order them. Men with no such family history are less likely to be screened. .... (More than half of such cancers are so slow-growing that they don’t affect health or longevity.) Men who don’t get screened are less likely to have biopsies and so are less likely to be diagnosed with prostate cancer — not because they develop the disease at a lower rate but because they get screened at a lower rate. What you don’t look for, you don’t find.

“If we biopsied men without a family history of prostate cancer at the same rate that we biopsy men with a family history, we’d find more prostate cancer in them as well,” Welch said. “Family history influences how hard we look for prostate cancer and therefore how much we find. The risk factor becomes a self-fulfilling prophecy.”

A 2016 study of increased prostate cancer screening in men with a family history of the disease concluded that the risk due to family history has been overestimated by nearly half. “The risk factor of family history is spuriously strengthened because men with a family history are exposed to greater scrutiny,” write Welch and Dr. Otis Brawley, chief medical officer of the American Cancer Society, in the Annals report.

Wealthier, better educated women are, however, more connected to the health care system and therefore get more mammograms, breast ultrasounds, and MRIs. The more scrutiny, the more likely that harmless cases of breast cancer are found. (The idea of “harmless” breast cancer sounds like an oxymoron, but an estimated one-half of breast cancers detected by screening would never cause problems even if undetected and untreated.)

Breast tumors found by imaging are much more likely to be harmless than those discovered by women or their physicians finding a breast lump. Income and education are therefore less likely to be a true risk factor for breast cancer and more likely to be a “risk factor” for undergoing screening. If poorer, less educated women were screened for breast cancer at the same rate as wealthier, better educated women, the socioeconomic risk factor would likely vanish.

Thyroid cancers are also scrutiny dependent, which is why when countries launch screening programs the incidence of the disease skyrockets (but death rates don’t, showing that what’s being found is a false epidemic). 

Welch and Brawley call for less focus on risk factors for developing cancers, since those numbers both determine and reflect who gets screened, and more on risk factors for death from cancer.

Published on Leave a comment on How Many Children Have Fetal Alcohol Disorders?

As many (most?) people know nowadays - drinking alcohol during pregnancy can have negative effects on the developing baby. Drinking a lot of alcohol can result in fetal alcohol syndrome, but drinking smaller amounts (frequently or binge drinking now and then) can also have negative effects, even though not as severe. The effects from alcohol are called fetal alcohol spectrum disorders - because the effects are along the spectrum from major to minor effects. Currently they're called  fetal alcohol syndrome, partial fetal alcohol syndrome, or alcohol related neurodevelopmental disorder. Effects are generally determined by the child's facial features, physical growth, neurobehavioral development, and prenatal alcohol exposure (esp. by interviewing the mother).

A recent study tried to determine how common are fetal alcohol spectrum disorders in the United States. The researchers screened 6639 first grade children in 4 communities from different areas of the US, and fully evaluated about 3000 children for fetal alcohol spectrum disorders. They found that the disorders ranged from 1.1% to 5% in the communities studied - and they felt that this is a conservative estimate. Interestingly, almost all of these newly diagnosed children had not been diagnosed with fetal alcohol spectrum disorders before the study. So it's easy to miss, and to misdiagnose- thus a "hidden problem".

How to avoid this problem? Don't drink alcohol during pregnancy. But unfortunately many women don't realize that they are pregnant in the first trimester, especially if the pregnancy is unplanned. The Centers for Disease Control (CDC) says on its site (official advice) that women should: "Stop drinking alcohol if they are trying to get pregnant or could get pregnant." What about men who drink alcohol and then conceive a child? There is also some research (mainly animal research) that alcohol can have negative effects on the father's sperm and the resulting fetus. Not fetal alcohol spectrum disorders, but perhaps other health effects which are still being determined.

From  journalist Pam Belluck's article at the NY Times: Far More U.S. Children Than Previously Thought May Have Fetal Alcohol Disorders

More American children than previously thought may be suffering from neurological damage because their mothers drank alcohol during pregnancy, according to a new study. The study, published Tuesday in the journal JAMA, estimates that fetal alcohol syndrome and other alcohol-related disorders among American children are at least as common as autism. The disorders can cause cognitive, behavioral and physical problems that hurt children’s development and learning ability.

The researchers evaluated about 3,000 children in schools in four communities across the United States and interviewed many of their mothers. Based on their findings, they estimated conservatively that fetal alcohol spectrum disorders affect 1.1 to 5 percent of children in the country, up to five times previous estimates. About 1.5 percent of children are currently diagnosed with autism.

The range of fetal alcohol spectrum disorders (also called FASDs) can cause cognitive, behavioral and physical difficulties. The most severe is fetal alcohol syndrome, in which children have smaller-than-typical heads and bodies, as well as eyes unusually short in width, thin upper lips, and smoother-than-usual skin between the nose and mouth, Dr. Chambers said. A moderate form is partial fetal alcohol syndrome. Less severe is alcohol-related neurodevelopmental disorder, in which children have neurological but not physical characteristics and it is known that their mothers drank during pregnancy.

Then there is the stigma that often makes mothers reluctant to acknowledge alcohol consumption. “When you identify a kid with FASD, you’ve just identified a mom who drank during pregnancy and harmed her child,” said Susan Astley, director of the Fetal Alcohol Syndrome Diagnostic and Prevention Network at the University of Washington, who was not involved in the study. While Dr. Astley, a longtime expert in the field, said she admired the researchers’ hard work, she said the reliability of the study’s numbers was hampered by several factors. For example, only 60 percent of eligible families in the schools allowed their children to be evaluated and more than a third of those children’s mothers declined to answer questions about drinking during pregnancy.

The authors of the study, which was funded by the National Institute on Alcohol Abuse and Alcoholism, acknowledged the study’s limitations and tried to partly compensate by providing a conservative estimate (of 1.1 percent to 5 percent) that is likely low and another estimate (of 3.1 percent to 9.9 percent) that is likely high. Dr. Chambers also said the results might not generalize across the country because although the four communities were diverse, they did not include a large, high-poverty urban area or certain rural or indigenous communities that struggle with high rates of alcoholism. The locations, which are not named in the publication, include small-to-midsize cities in the Midwest and Rocky Mountains, a Southeast county and a Pacific Coast city the authors identified in interviews as San Diego. [Original study.]

Published on Leave a comment on Chronic Diseases Raise Cancer Risk, and Exercise Lowers It

A new observational study from Taiwan found that having one of eight chronic diseases, such as heart disease or diabetes, or their markers (e.g. high cholesterol levels as a marker for heart disease), also significantly raises the person's odds of developing cancer or dying from cancer. The study estimated that these diseases or markers accounted for about 20% of all new cancers and 39% of all cancer deaths. That's about the risk of 5 lifestyle factors combined (smoking, alcohol consumption, obesity, unhealthy diet, and lack of exercise) contributing to cancer development and death.

The eight chronic diseases and markers were: cardiovascular disease (markers for which include blood pressure, total cholesterol, and heart rate), diabetes, chronic kidney disease (markers for which include proteinuria and glomerular filtration rate), pulmonary disease, and gouty arthritis (for which uric acid is a marker). The higher the chronic disease and marker score, the higher the risk of developing cancer and cancer death (a dose-response). Chronic diseases and markers were associated with a shortened lifespan -  about 13.3 years in men and 15.9 years in women.

But the good news is that regular physical exercise lowers the risk of developing cancer by about 48% and the risk of cancer death by 27%. That's huge!  So physical exercise and activity could be viewed as "cancer prevention" strategies. The researchers pointed out that additional cancer prevention strategies are avoiding smoking (very important), avoiding excessive alcohol consumption, maintaining healthy weight, and a healthy diet. From Science Daily:

Substantial impact of chronic diseases on cancer risk

Several common chronic diseases together account for more than a fifth of new cancer cases and more than a third of cancer deaths, finds a study published by The BMJ today. The findings show that the cancer risks from common chronic diseases, such as heart disease and diabetes, are as important as those from five major lifestyle factors combined.

A team of researchers based in the US and Taiwan therefore set out to investigate the combined effect of eight common chronic diseases or disease markers (for example, high blood pressure as a marker of heart disease) on cancer risk compared with lifestyle factors. They also explored whether physical activity could reduce the cancer risk associated with chronic diseases and disease markers. The study involved 405,878 men and women in Taiwan with no history of cancer .... underwent a series of medical tests between 1996 and 2007. .... Participants were followed for an average of 8.7 years.

The researchers found that cardiovascular disease markers, diabetes, chronic kidney disease markers, pulmonary disease, and gouty arthritis marker were individually associated with risk of developing cancer or cancer death. Higher chronic disease risk scores based on these diseases or markers were linked with an increased risk of developing cancer and cancer death, with the highest level associated with a more than twofold increase in risk of developing cancer and a fourfold increase in risk of cancer death.

High chronic disease risk scores were also associated with substantial reduction in life span. The highest scores were associated with 13.3 years of life lost in men and 15.9 years of life lost in women. Together, these chronic diseases and markers accounted for more than one fifth of all new cancers and more than one third of all cancer deaths in this study population, which was similar to the contribution of five major lifestyle risk factors combined -- smoking, insufficient physical activity, insufficient fruit and vegetable intake, alcohol consumption, and obesity.

The researchers also found that physical activity was associated with a nearly 40% reduction in the excess risks of cancer and cancer death associated with chronic diseases and markers. [Original study.]