Study Links Eating Whole Grains with Lower Risk of Liver Cancer

A large new study has found that regularly eating whole grains may significantly lower the risk of liver cancer. The study, published online in JAMA Oncology, followed 125,000 men and women for an average of 24 years, gathering information on participants' diet at regular intervals over that time.

The researchers found that those who ate the greatest amount of whole grains had a 37 percent lower risk of a common type of liver cancer (hepatocellular carcinoma) compared to those who ate the least. And benefits accrued with a relatively modest intake of whole grains, only around 33 grams a day. That's just over the amount in two slices of 100 percent whole-wheat bread, which has about 16 grams of whole grains per slice.

Despite being a large, well-designed study, the researchers were appropriately cautious in their conclusions and highlighted their study's limitations. There were relatively few cases of liver cancer among the participants, which makes it harder to rule out chance findings. Hepatitis infection, which is an important risk factor for liver cancer, was not well documented in participants, and so could not be fully taken into account in analyses, possibly impacting the accuracy of results.  And finally, the link between whole grains and liver cancer has only been looked at in a very small number of studies, so there is not yet enough evidence to draw solid conclusions about the links between the two.

Taking all that into account, the paper ends:

If our findings are confirmed, increasing whole grain consumption may serve as a possible strategy for prevention of primary HCC [liver cancer]. 

And if confirmed, these results would also further build on the already great evidence on the overall health benefits of a diet rich in whole grains, which we've written about previously in CNiC. From Be Less Refined: Eat More Whole Grains:

Whole grains are packed with fiber and other key nutrients and have been found to lower the risk of diabetes, heart disease, and certain cancers. They can also help keep weight in check and the digestive system running like clockwork.

For overall health benefits, the goal should be to eat three or more servings of whole-grains a day. One serving of whole grains is: 

• 1 slice of 100 percent whole-wheat bread 
• 1 cup of dry whole-grain cereal 
• 1/2 cup of cooked brown rice, wild rice, or hot whole-grain cereal, like oatmeal 

While whole grains taste great, they can also take a bit of getting used to if you're used to eating mostly refined-grain foods, like white bread and white rice. So, take a little time to transition. Add one slice of 100 percent whole-wheat bread to your sandwich to start. Or mix equal parts, brown rice and white rice, or regular pasta with whole-grain pasta. Then, slowly make whole grains a bigger part of the total grains in your diet. 

The benefits are well worth the effort. 

Video Tour: 8 Ways to a Healthier Weight - and Lower Risk of Cancer

Take a quick video tour of the latest from our 8IGHT WAYS series: 8IGHT WAYS to a Healthier Weight - and Lower Risk of Cancer.  Whether you're looking to maintain your weight or lose a few pounds, this new guide is filled with simple, useful, and brief tips to help you on your way.  Find it, and other in the series, here. 

Physical Activity Lowers Cancer Risk - More People Should Probably Know That

A new study has found that a large majority of the public may be unaware that lack of physical activity can increase the risk of cancer.

The study, out of Washington University in St. Louis and published Wednesday in the Journal of Health Communication, included a diverse sample of participants who were asked to list three diseases caused by physical inactivity. Just three percent of 351 respondents listed cancer, while over 60 percent listed diseases such as heart disease or diabetes.

These findings add to those of other studies and surveys that have shown that: while many people know that a healthy lifestyle overall can help prevent cancer, many are often unsure about the exact types of behaviors that can lower cancer risk.

A 2017 American Institute for Cancer Research (AICR) survey, for example, found that the vast majority of respondents knew that smoking and sun exposure increased cancer risk, yet well under half identified physical inactivity as a risk factor.

There is a large amount evidence, however, showing the benefit of regular physical activity in relation to cancer.  It can lower the risk of breast cancer, colon cancer, and endometrial cancer. It can help with weight control - a key cancer risk factor. And in cancer survivors, it can improve mood, boost energy level, and possibly lower the chance of recurrence.

Physical activity has been an integral part of the Siteman Cancer Center's Your Disease Risk tool since its launch in 2000, and regular physical activity is recommended throughout Siteman's 8IGHT WAYS cancer series (see below).

Erika Waters, lead author of the Washington University study and Associate Professor of Surgery at the School of Medicine, commented: "People might be more likely to exercise if they understand just how important physical activity is to their overall health - not just their heart health."

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HPV Vaccine Prevents Cervical Pre-Cancer - New Report

By Hank Dart

An important new report further confirms that the HPV vaccine is both safe and extremely effective at preventing cervical pre-cancers that could develop into cervical cancer.

The report, published Wednesday in the Cochrane Library, reviewed the results of 26 HPV vaccine clinical trials that included over 73,000 girls and women ages 15 - 45 followed for between six months and eight years.

Human papillomavirus (HPV) is a common sexually transmitted infection, with up to half or more of adults -- men and women -- getting infected at some point in their lives.  Most of these infections clear up on their own.  Some, however, can persist.  And if they are of a high-risk type of HPV, they can increase the risk of certain cancers -- particularly cervical cancer.  Around 70 percent of cervical cancers are linked to HPV16 and HPV18. This new review assessed the potential benefits and risks of HPV vaccines that target these two high-risk types.

The researchers found the HPV vaccine to be very effective at preventing cervical pre-cancers -- abnormal changes in cervical cells that can develop into cancer.

In females aged 15 - 25 who did not have a high-risk HPV infection at the beginning of the study, those who received the HPV vaccine had a 99% lower risk of developing HPV16/18-linked cervical pre-cancer (CIN2+) compared to those who did not receive the vaccine (see figure).  And even when including those who may have had an HPV infection at the beginning of the study, those who were vaccinated had a 54 percent lower risk of HPV16/18-linked cervical pre-cancer (CIN2+) than those were weren't.

The researchers also found no difference in rates of serious side effects between those who were vaccinated and those who weren't. But they also noted that more extensive data are likely needed to fully explore any impact on such rare health events.

Our very first post in Cancer News in Context way back in 2003 was on the potential benefits of the, then new, HPV vaccine - "A Shot in the Arm for Cancer Prevention."  Now in 2018, this new report in the Cochrane Library demonstrates further the true prevention benefits of the vaccine.

In a prepared statement, Dr. Jo Morrison, Consultant in Gynaecological Oncology at the Musgrove Park Hospital in the United Kingdom, said:

"These data show that immunizing against HPV infection protects against cervical pre-cancer, and it is very likely that this will reduce cervical cancer rates in the future."

Yet, rates of vaccination in the United States lag.

Current guidelines recommend a 2-dose series of the vaccine for both boys and girls at age 11 or 12. In 2016, however, only 44 percent of boys and 55 percent of girls ages 13-17 had had 2 or more doses.  Rates of other childhood vaccinations, by comparison, are often around 90 percent or higher.

To bring rates of HPV vaccination up, we need to effectively communicate to parents the importance of the vaccine and its demonstrated safety, train physicians to recommend it, and implement policies that promote and sustain its use.

Compared to many other steps to lower cancer risk, HPV vaccination is relatively quick and simple. And it potential benefits are huge.  To realize these benefits, we just need more shots in the arm.

New Diet Study Finds "Ultra-Processed" Foods May Be Linked to Cancer Risk

by Hank Dart

A new study out of France highlights another possible reason to avoid eating too many highly processed foods:  They may increase the risk of cancer.

The paper, published yesterday in the British Medical Journal, followed close to 105,000 adults for an average of 5 years.  Along the way, participants were asked to regularly report their dietary intake and any health events, such as a diagnosis of cancer.

Foods were then categorized into groups, with an "ultra-processed" group including foods like: soda (diet or sugary); mass-produced sweets; meats with preservatives other than salt; instant noodles and soups; and foods with industrial food additives and agents.

The proportion of participants' diets that was made up of ultra-processed foods was determined by the weight of food, rather than by calories.  This was done to take into account the potential impact of processed foods that have few, if any, calories, like diet sodas.

The researchers found that for every 10 percent increase in the proportion of ultra-processed foods in the diet, the overall risk of cancer increased by 12 percent and the risk of post-menopausal breast cancer increased by 13 percent.  

Risks were more pronounced when comparing high intake of processed foods with low intake. Participants who ate the most ultra-processed foods had a 21 percent higher risk of cancer overall and a 39 percent higher risk of post-menopausal breast cancer.  They also may have had a higher risk of colorectal cancer, but those results were less reliable.

In the analyses, researchers took into account many factors that could have swayed the results because they could be related to both processed food intake and cancer.  These included factors such as physical activity level, body mass index, alcohol intake, tobacco use, and overall diet quality.

In an accompanying editorial, Adriana Monge of the National Institute of Public Health in Mexico City and Martin Lajous of the T.H. Chan School of Public Health at Harvard University praised the researchers for their detailed study but recommended caution in interpreting such initial results.

"...as with any observational study, confounding by unknown factors common to consumption of ultra-processed foods and cancer outcomes cannot be excluded." 

"Their interesting results require replication and further refinement."

"We are a long way from understanding the full implications of food processing for health and wellbeing."

While more study is needed on the possible links between ultra-processed foods and cancer, well-established dietary recommendations call for limiting certain types of processed foods, which can be high in calories, sodium, refined grains, added sugar, and unhealthy fats -- and low in healthy nutrients.

A largely plant-based diet that is low in unhealthy processed foods and filled with fruits, vegetables, beans, and whole grains is best for overall health and can lower the risk of many important chronic diseases, including cancer.

Ready for the Taking: The Economic & Health Benefits of Implementing Cancer Prevention

For a topic that always gets a lot of news coverage, health and healthcare has been in the media even more than usual since the 2016 election. While it’s unclear exactly where the current debates on Obamacare and the American Health Care Act will lead, a Sounding Board article in today’s New England Journal of Medicine by Karen Emmons, PhD and Washington University’s Graham Colditz, MD, DrPH makes one thing clear: we could drastically cut the burden of cancer if we invest appropriate health resources to successfully implementing the things we already know could prevent more than half of all cancers. 

In the sweeping article, Emmons and Colditz detail the often large disparities between states in rates of healthy behaviors that can lower cancer risk. In the nation as a whole, for example, 15 percent of people smoke, but rates vary by 17 percentage points between Utah (9.7 percent) and West Virginia (26.7 percent). Rates of obesity vary by 16 percentage points between Colorado (20.2 percent) and Louisiana (36.2 percent). And rates of physical inactivity vary 15 points between Colorado (16.4) and Mississippi (31.4 percent). Such inequality can be parsed further, with rates varying within states by county and socioeconomic groups, for example.  Vulnerable populations — those in poverty, or with mental health issues, or in minority groups — often have worse health profiles and health outcomes compared to others.

The effort to combat smoking — one of the greatest public health success stories of the past 50 years — still has great room for improvement. State cigarette taxes on a pack of cigarettes, which demonstrably leads to lower smoking rates, vary from less than 25 cents a pack to over four dollars. And evidence-based programs to help people quit smoking are unevenly implemented and unevenly funded not only between states but across town. Devoting enough resources to fully realize the benefit of controlling tobacco use nationwide will have large health and economic benefits.

 Emmons and Colditz write as an example:

“Every $1 expended on a comprehensive smoking-cessation program in Massachusetts was associated with a return on investment of $2.12.”

This Massachusetts program, MassHealth, expanded evidence-based tobacco-cessation coverage in low-income smokers and included effective pharmacological approaches. The program lowered rates of smoking in this group by 26 percent — a group with typically static cessation rates, and the annual rate of admissions for heart attacks dropped 46 percent, and admissions for coronary atherosclerosis dropped 49 percent.

Other cancer-prevention approaches — increasing activity, controlling weight, improving diet, and getting youth vaccinated against HPV, say — also have vast potential for health benefits nationwide.  If they get implemented and implemented effectively.  Yet, efforts to determine the best way to get people and communities to adopt such behaviors — and then to put these into practice — are under-resourced. As Emmons and Colditz write:

“Simply put, as a nation, we continue to underinvest in primary prevention and screening and fail to adopt strategies to ensure that all population groups benefit equally from our knowledge of cancer prevention.”

Yet, as with tobacco cessation, we know certain approaches work with these other risk factors. Rates of HPV vaccination lag significantly between the US and Australia. The US lacks a comprehensive, effective vaccination program, which leads to lower rates overall and large variability between states, with 68.0 percent of girls fully vaccinated in Rhode Island but only 24.4 percent in Mississippi. Australia, on the other hand has an overall rate of 74 percent for girls and one nearly as high for boys.

The difference? HPV vaccination in Australia is mandated for boys and girls and is paid for by the Australian government. The high vaccination rates have led to a substantial drop in positive Pap tests and the need for women to return for after-test follow-up. The future drop in rates of cervical cancer because of HPV vaccination should be substantial.

We should build on such lessons and learn what works best in the US for implementing cancer-prevention strategies. Research should focus on the patient, provider, organization, and policy levels to increase cancer prevention interventions to lower healthcare costs and patient mortality. Such as,

• Funding for safety net clinics (at-risk populations). Health equity is key. We must be sure to focus on preventing cancer in the most vulnerable populations. 
• Implementing environment and policy changes. Talking multiple levels of society works, such as smoking bans at work, schools, and restaurants; and required HPV vaccinations for school children. 
• Fostering a focus on prevention in clinical settings. This can include: Patient education and provider interaction about smoking cessation, lifestyle factors, and recommended screening. 

While learning to effectively put into practice those things we already know can prevent cancer may not be as flashy or newsworthy as the discovery of a new treatment or previously unidentified gene mutation, this doesn’t mean it doesn’t deserve the same attention and the same resources.

The real power of prevention has yet to be realized - or even really appreciated. Yet, prevention has been shown to work in public health interventions, to be cost effective, to lower mortality, and to have a high return on investment.  It is an opportunity that should not be squandered.

As Emmons and Colditz conclude:

“ Although many efforts are under way to maximize our knowledge about the causes and treatments of cancer, we can achieve reductions in the cancer burden right now by doing what we already know works. Enhanced investment in research that increases our understanding of how to implement the knowledge we have is needed. Our moonshot is right here — ready for the taking.”

Cancer Prevention Benefits of the Hepatitis B Vaccine (Infographic)

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A Meaty Topic: Red Meat, Cancer Risk, and the Benefits of a Plant-Based Diet

By Yikyung Park, ScD

A recent report on red and processed meat and cancer risk, written by the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO), sent shockwaves worldwide. After reviewing existing evidence, the report concluded that processed meat consumption is a cause of cancer and red meat consumption is probably a cause of cancer, too. Although the adverse effect of meat on health has been known for quite a while, many people seemed to be surprised by the IARC report.

As a part of IARC’s Monographs Programme, 22 experts from 10 countries reviewed more than 800 different studies on cancer in humans and concluded that high consumption of red and processed meat is carcinogenic to human. Most convincing evidence came from studies on colorectal cancer. For every 100 grams per day of red meat consumption , colorectal cancer risk incased by 17 percent.  One hundred grams is equal to about 3.5 ounces of steak, or a piece of meat about the size of a deck of cards.  Every 50 grams per day of processed meat consumption (about 6 slices of bacon) also increased colorectal cancer risk by 18%.

Although these risks aren't large, they are still important.

Cutting back on red and processed meat offers those at increased risk of cancer (such as those with a family history of the disease or who have previously had cancer) a relatively simple option for helping to lower their risk.

More broadly, the meat/cancer link has huge public health implications simply because so many people eat meat, with consumption increasing worldwide. On average in the United States, people eat about 50–100 grams per day of red meat and some people eat more than 200 grams daily. According to the U.S. Department of Agriculture Commodity Consumption by Population data, in 2012, Americans consumed on average 163 grams of total meat daily, of which 92 grams was red meat and 54 grams was poultry. Red meat consumption was higher in men, younger people, and obese people.

Red meat refers to unprocessed animal meat such as beef, veal, pork, lamb, and goat. Processed meat refers to any meat (such as, beef, pork, chicken, turkey) that has been salted, cured, fermented, smoked, or processed to enhance flavor or improve preservation. Examples of processed meat are hot dogs, luncheon meat, ham, sausages, corned beef, beef jerky, and canned meat. When meat is cooked at high temperatures (e.g., grilling, barbecuing, and pan-frying), it produces heterocyclic amines (HAA) and polycyclic aromatic hydrocarbons (PHA), which are known to cause cancer in animals. Also, meat contains heme iron that increases formation of N-nitroso compounds (NOC), another cancer causing agents. Nitrate and nitrite that are added to processed meats during the processing also forms NOC.

Meat is a good source of protein and B vitamins, which are needed to maintain health, but also high in saturated fat and may contain potentially cancer-causing chemicals mentioned above. Numerous studies have showed that high consumption of red and processed meat was related to an increased risk of colorectal cancer, but also an increased risk of coronary heart disease, diabetes, and premature death.

Furthermore, people who eat high amounts of red and processed meat also tend to eat more high-fat foods, sweet desserts, and refined grains, but fewer fruits and vegetables. This kind of overall dietary pattern has also been linked to an increased risk of cancer as well as other chronic diseases. 

On the other hand, a Mediterranean type-diet that is high in fruit, vegetables, beans, and whole grains and low in consumption of red meat has many health benefits. 

This recent wave of media coverage on the risks of red and processed meat - while a bit overblown - did highlight the important role that a largely plant-based diet has in lowering cancer risk and improving overall health.  Cutting back on red and processed meat by choosing more poultry, fish, and legumes is one step you can take.  Choosing more fruits, vegetables and whole grains while cutting back on refined grains and unhealthy fats (like saturated and trans fats) are others.  

Making such changes isn't always easy but everyone can do it.  The key is to start small and build from there. Change just one thing at a time.  Try out "meatless Mondays."  Or add an extra vegetable to your dinners a few times a week.   When such changes become a habit, add on other healthy options.  

For additional healthy eating and lifestyle tips, see our series - 8IGHT WAYS to Prevent Cancer (website).

References

Bouvarda V et al. Carcinogenicity of consumption of red and processed meat. Lancet Oncology, 2015. Available online 29 October 2015

Micha R et al. Red and processed meat consumption and risk of incident coronary heart disease, stroke, and diabetes mellitus: a systematic review and meta-analysis. Circulation. 2010;121(21):2271-83.

Sinha R et al. Meat intake and mortality: a prospective study of over half a million people. Arch Intern Med. 2009;169(6):562-71.

Sofi F et al. Adherence to Mediterranean diet and health status: meta-analysis. BMJ. 2008;337:a1344.

USDA Economic Research Service. http://www.ers.usda.gov/data-products/commodity-consumption-by-population-characteristics.aspx

Photo: Hot Pastrami Albany by Steven Depolo (CC License, CC BY 2.0)

Practical Steps to Prevent Breast Cancer: Day 4 - Don’t Smoke, and Avoid Other People’s Smoke, Too

It's day four in our nine day series highlighting key steps and practical tips that can help women lower their risk of breast cancer. Previous days.   

_ _ _ _

Day 4 - Don’t Smoke, and Avoid Other People’s Smoke, Too

This really goes without saying: Don’t smoke, and avoid other people’s smoke, too. 

Smokers and non-smokers alike know how bad smoking (and secondhand smoke) is to their health. On top of lowering quality of life and increasing the risk of heart disease, stroke, and at least 15 cancers – including breast cancer – it also causes smelly breath, bad teeth, and wrinkles. Now that’s motivation to stay smoke-free or quickly get smoke-free. 

Though electronic cigarettes can seem like safe alternatives to standard cigarettes, so much is unknown about their risks and benefits that it’s important to avoid them as well. For help quitting smoking, there are many FDA-approved nicotine-replacement options that have been shown to be safe and to double chances of success.

Tips and Tricks – Smoking

It’s hard to quit, so keep trying. If there’s one thing we all know about quitting smoking, it’s that it’s hard. It takes most people six or seven tries before they quit for good. So, if at first you don’t succeed, try try again. Don’t give up. Over a thousand Americans successfully quit smoking every day.

Talk to a health-care provider. Seeing a doctor or other health care professional may not be the first thing you think of when thinking about ways to quit smoking, but they can be fabulous sources of information and cessation aids that can help you kick the habit. Studies show that seeing a doctor for help quitting can double your chances of success.

Visit smokefree.gov. Whether you are just thinking about quitting, want help quitting, or are looking for information about quitting for a friend of family member, the federal website smokefree.gov is the place for you. They also host the innovative text message cessation program, smokefreetxt, and sites focused on specific groups: smokefreeVET. smokefreewomen, smokefreeteen, and the Spanish-language smokefreeespanol.

Call 1-800-QUIT-NOW. Similar to the federal smokefree.gov, 1-800-QUIT-NOW (1-800-784-8669) will connect you to cessation information and resources in your state.

Talk to your kids about smoking. If you have kids – or grandkids or nieces and nephews – it’s important to with talk them from a young age about the dangers of tobacco and the need to stay away from cigarettes and other tobacco products.

Next Steps – Smoking

Looking for more in-depth information on smoking? Here are some good sources:

Smokefree.gov
http://smokefree.gov

American Cancer Society
http://goo.gl/glMlZx

The Truth Campaign
http://thetruth.com

Excerpted from TOGETHER - Every Woman's Guide to Preventing Breast Cancer

Photo: Flickr/machechy (CC license)

What Do the Numbers Say About Breast Cancer Prevention?

Larger version - including "presentation mode"

Larger version - including "presentation mode"

Physical Activity and Cancer Prevention: "Step It Up!" Walking Campaign

by Katy Henke

In early September 2015, Vivek Murthy, MD, the Surgeon General of the United States, began a national campaign to increase the amount of physical activity Americans engage in each day (see video below).  The campaign, called Step It Up!, works not only to get Americans walking more but also to help facilitate walking by increasing the number of safe and reliable walking paths in people's cities and neighborhoods (see video below).

Convincing evidence shows that exercise can lower the risk of breast, colon, and uterine cancers (1). Many national organizations, such as the Centers for Disease Control (2), recommend at least 30 minutes of moderate to vigorous physical activity at least 5 days per week to help prevent cancer.

Even if walking's not your thing, there are many other ways to take part in the Step It Up! campaign while reducing your cancer risk. Choose any physical activity you enjoy, such as gardening, cycling, or dancing. And try doing these activities with someone else to keep you motivated.

For long lasting health effects, make your exercise routine a habit in your household. Set aside time each day to ensure you are able to make exercise a health priority. If you feel overwhelmed at exercising that much at one time, break up your routine into 10 minutes, three times a day in order to meet your goal. For those adults who have children, walk with them to school in the morning and encourage outside activities when appropriate. Healthy habits can start at a young age too, and help reduce their risk of cancer.

In addition to helping prevent cancer, regular exercise has other great benefits, including (3):

• Helping with weight control
• Reducing the  risk of cardiovascular disease, type 2 diabetes
• Strengthening  muscles and bones
• Improving  mental health and mood
• Improving ability to complete daily tasks

To learn more:

Step It Up! walking campaign 

8IGHT WAYS to Stay Healthy and Prevent Cancer.

Photo: Flickr/pensiero (CC license)

References

1. World Cancer Research Fund; Continuous Update Project. Cancer Prevention & Survival: Summary of global evidence on diet, weight, physical activity & what increases or decreases your risk of cancer. September 2015 Edition. http://www.wcrf.org/sites/default/files/CUP-Summary-Report.pdf

2.  Center for Disease Control and Prevention. How much physical activity do adults need? 2015 Jun 4. http://www.cdc.gov/physicalactivity/basics/adults/.

3.  Center for Disease Control and Prevention. Physical activity and health. 2015 Jun 4. http://www.cdc.gov/physicalactivity/basics/pa-health/.

Eating to Lower Cancer Risk: Replacing Superfoods with Science

by Graham Colditz, MD, DrPH

Article originally appeared in the Washington University - Institute for Public Health Blog

When it comes to cancer, there are few topics as supercharged as diet. A quick search of “diet and cancer” in Google News alone returns over 3 million stories. And yet, however large these numbers are, they don’t fully capture the passion that many people feel about the food/cancer link. There’s something special, elemental even, about making sure the food we eat is as safe and as healthy as possible – for us and for our loved ones.

Yet, however motivated people are to make healthy food choices, there are a lot of mixed signals out there on what to eat to lower cancer risk. Magazines and websites often tout “superfoods” and “cancer-busters” that rarely match up with official eating recommendations, and even these official recommendations seem to change month to month with the release of new – and often seemingly contradictory – study results.

Trying to decide what to eat can be an exercise in frustration, a sentiment captured perfectly in findings from a 2007 paper on public beliefs about cancer prevention. In this national sample survey, over 70 percent of respondents agreed with the statement that “there were so many recommendations about preventing cancer that it’s hard to know which ones to follow” (1).

The reality, though, is that when all the evidence on the links between diet and cancer are looked at together, clear and simple messages rise to the surface. These messages contain no “superfoods” or “cancer-busters” and, so, may not always lead the headlines. But what they may lack in headline-grabbing flash, they more than make up for by being recommendations based in solid science. And that’s really what matters.

Watch the calories
We see them listed everywhere and so have become inured to them in a way, but calories really matter when it comes to cancer risk. In fact, they’re probably the single most important aspect of diet when it comes to preventing cancer. Consistently eating too much can lead to weight problems. And, among other health risks, obesity is an established risk factor for at least eight different cancers and is responsible for 120,000 cases each year in the United States (2,3).

Over two-thirds of the nation is either overweight (BMI 25 – 29.9) or obese (BMI 30 or over), and studies consistently demonstrate that people have difficulty recognizing if they – or their children – are an unhealthy weight. Add to this the increasingly sedentary lifestyles that go along with modern society, and it takes a concerted effort by most people to moderate calories and keep weight in check over the course of their lives (4). These simple tips can help keep calories and weight in control:

• Avoid sugary drinks, like sodas, energy drinks, and sports drinks. Even 100% juice should be kept to small amounts each day.
• Focus on eating mostly plant-based foods, like whole grains, fruits, and vegetables. 
• Be a more mindful eater. Start with smaller portions, eat slowly, and try to eat only when truly hungry. 
• Fit physical activity into each day. More is almost always better, but any amount is better than none. 
• Weigh your self on most days. It’s easy, keeps surprise weight gain at bay, and helps you make diet/activity adjustments in a timely manner.

Limit food from animals
You don’t need to go full vegetarian – unless you want to – but there’s compelling data that eating fewer animal-based foods can lower the risk of colon cancer, prostate cancer, and possibly breast cancer (5-7). Try to eat fewer than three servings of red or processed meat each week, and choose more plant-based sources of protein and fat, like nuts, beans, and vegetables.


Focus on fruits, vegetables, and whole grains
The data linking fruits and vegetables as a whole with lower cancer risk aren’t as strong as you might think, but there are still a lot of compelling reasons to eat more plant-based foods when you look at individual cancers and specific foods (4,8). For example, diets rich in fruits and vegetables have been shown to lower lung cancer risk. Tomatoes and tomato-based foods have been shown to lower the risk of prostate cancer (8). Diets with a low glycemic load – which typically have fewer refined grains and sugars – lower the risk of endometrial cancer (9). And diets high in fiber can lower the risk of colon cancer 5. Growing data also suggest that eating higher amounts of vegetable protein in youth (from sources like soy, nuts, and vegetables) may improve breast health and lower the risk of adult breast cancer (10). Shoot for at least five servings of fruits and vegetables each day, and at least three servings of whole grains. Keep refined grains (like white bread and white rice) to a minimum.


‪Drink alcohol in moderation, if at all
‪
Often lost in the messages about the heart-health benefits of moderate drinking are its related cancer risks. Moderate alcohol intake has been shown to increase the risk of colon cancer, with just a few drinks a week increasing breast cancer risk 5. Drinking in youth and young adulthood seems particular hazardous for later adult breast cancer risk (figure) (11).

Older adults who likely stand to benefit from the heart-health benefits of moderate drinking (less than one drink a day for women and less than two for men) probably don’t need to stop drinking. Those adults who don’t drink, though, shouldn’t feel the need to start. Without saying, youth should completely avoid alcohol, and college-aged adults should minimize alcohol and avoid binge drinking, which can lead to problem drinking and other risky behaviors.

‪ Data source: Liu et al, 2013 11

Consider a daily multivitamin.
‪
Though it remains a topic of debate, a daily multivitamin is a cheap and potentially powerful nutrition insurance policy (4). When added on top of a healthy diet, the vitamins and minerals in a daily multivitamin may provide added protection against a number of chronic diseases, including cancer. Calcium and vitamin D have been found in key studies to lower the risk of colon cancer. Folate may also lower colon cancer risk, as well as lower the excess risk of breast cancer in women who regularly drink alcohol (12,13). Choose a simple 100% Daily Value (DV) multivitamin, and avoid “mega” vitamins.


‪The Bottom Line
The food we eat can have an important impact on cancer risk. Key goals are to keep calories in check, eat more plant-based foods, limit red and processed meats, and avoid too much alcohol. A daily 100% DV multivitamin can be a good nutrition insurance policy.

Photo: Flickr/Colin Brace

Key references

1 Niederdeppe, J. & Levy, A. G. Fatalistic beliefs about cancer prevention and three prevention behaviors. Cancer Epidemiol Biomarkers Prev 16, 998-1003, doi:10.1158/1055-9965.EPI-06-0608 (2007).

2 American Institute for Cancer Research. Updated Estimate on Obesity-Related Cancers, <http://www.aicr.org/cancer-research-update/2014/march_19/cru-updated-estimate-on-obesity-related-cancers.html> (2014).

3 Renehan, A. G., Tyson, M., Egger, M., Heller, R. F. & Zwahlen, M. Body-mass index and incidence of cancer: a systematic review and meta-analysis of prospective observational studies. Lancet 371, 569-578, doi:S0140-6736(08)60269-X [pii]10.1016/S0140-6736(08)60269-X (2008).

4 Willett, W. C. & Stampfer, M. J. Current evidence on healthy eating. Annu Rev Public Health 34, 77-95, doi:10.1146/annurev-publhealth-031811-124646 (2013).

5 World Cancer Research Fund / American Institute for Cancer Research. Continuous Update Project Report. Food, Nutrition, Physical Activity, and Cancers or the Colon and Rectum. (2011).

6 Michaud, D. S. et al. A prospective study on intake of animal products and risk of prostate cancer. Cancer Causes Control 12, 557-567 (2001).

7 Colditz, G. A., Bohlke, K. & Berkey, C. S. Breast cancer risk accumulation starts early: prevention must also. Breast Cancer Res Treat 145, 567-579, doi:10.1007/s10549-014-2993-8 (2014).

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10 Berkey, C. S. et al. Vegetable protein and vegetable fat intakes in pre-adolescent and adolescent girls, and risk for benign breast disease in young women. Breast Cancer Res Treat 141, 299-306, doi:10.1007/s10549-013-2686-8 (2013).

11 Liu, Y. et al. Alcohol intake between menarche and first pregnancy: a prospective study of breast cancer risk. J Natl Cancer Inst 105, 1571-1578, doi:10.1093/jnci/djt213 (2013).

12 Zhang, S. et al. A prospective study of folate intake and the risk of breast cancer. JAMA 281, 1632-1637, doi:joc81167 [pii] (1999).

13 Zhang, S. M. et al. Plasma folate, vitamin B6, vitamin B12, homocysteine, and risk of breast cancer. J Natl Cancer Inst 95, 373-380 (2003).

New Dietary Recommendations Take Innovative Approach - and Not Everyone's Happy About It

By Yikyung Park, ScD

Editor's note: Not surprisingly, the recently released report from the Dietary Guidelines for Americans Advisory Committee was met with both praise and scorn.  Many in the medical and health fields lauded the report for its innovative approach to considering both the food environment and sustainability, as well as for its healthy eating recommendations, which focussed largely on consuming more plant-based foods. The food industry, however, took issue with many aspects of the report, with the meat industry seeming particularly up-in-arms to fight the report's recommendation to cut back on both red meat and processed meat.  A recent Op-Ed in New York Times highlights the hot-button issue red meat and health has become since the report's release.  CNiC's Yikyung Park explains these new recommendations, the process behind them, and some details about the new red meat guidelines.   

A recent report from the 2015 Dietary Guidelines Advisory Committee (DGAC) is gathering much attention from the public as well as from the food industries. Why and what is in this report?

Since 1980, the Department of Agriculture (USDA) and the Department of Health and Human Services (DHHS) jointly published the Dietary Guidelines for Americans every 5 years. To update the Guidelines, the Dietary Guidelines Advisory Committee (DGAC) is assembled and

reviews scientific and medical literature. The Committee submits a report that includes recommendations (not the actual guidelines) for a new set of dietary guidelines to the Secretaries of the USDA and DHHS. The USDA and DHHS write the actual guidelines after reviewing the report and comments submitted by the public. A new 2015 Dietary Guidelines for Americans is scheduled for release at the end of this year.

The recommendations for healthy eating that make up the Guidelines have been largely consistent through the years, but new scientific evidence results in some changes from edition to edition. Of note, the 2015 Guidelines Committee makes a recommendation that emphasizes dietary patterns and foods over nutrients and in doing so considers the importance of food environments and sustainability. The committee recognizes “the significant impact of food and beverages on environmental outcomes, from farm to plate to waste disposal, and, therefore, the need for dietary guidance to include the wider issue of sustainability.” The committee also highlights the importance of the food environment– those external factors that influence our food choices, from advertising to cafeteria menus – in making healthy choices.

In the report, the Committee recommends a healthy diet which is higher in vegetables, fruits, whole grains, low-fat (or non-fat) dairy, seafood, legumes, and nuts; moderate in alcohol; lower in red meat and processed meats; and low in sugar-sweetened foods and drinks and refined grains. The report also recommends actions for not only individuals and families, but also for communities, industry, and government to achieve and maintain healthy dietary patterns and the levels of physical activity needed to promote a healthy U.S. population. Among those are:

• Aim to make healthy lifestyles and prevention a national and local priority and reality.

• Establish healthy food environments.

• Seek a paradigm shift in health care and public health toward a greater focus on prevention and integration with food systems.

• Establish healthy food environments.

• Support and expand access to healthy built environments and advocate wide community use.

• Maintain strong support for federal food and nutrition programs.

• Recognize and place priority on moving toward a more sustainable diet consistent with the healthy dietary pattern options described in this DGAC report. Access to sufficient, nutritious, and safe food is an essential element of food security for the U.S. population. A sustainable diet helps ensure this access for both the current population and future generations.

The Committee’s recommendation for eating less red meat and processed meat is strongly supported by a large body of scientific evidence on its adverse effects. Diets high in red meat and processed meat have been found to increase the risk of cardiovascular disease, diabetes, and cancer, especially colorectal cancer, as well as an increased risk of premature death. In addition, accumulating evidence as summarized in the report indicates that “in general, a dietary pattern that is higher in plant-based foods, such as vegetables, fruits, whole grains, legumes, nuts, and seeds, and lower in animal based foods is more health promoting and is associated with lesser environmental impact (GHG emissions and energy, land, and water use) than is the current average U.S. diet.”

This new report, however, is being heavily criticized by the meat industry, especially for taking environmental sustainability into consideration in making recommendations. But food industry’s attack on the dietary guidelines is not new. Whenever the DGA is updated, the food industry actively lobbies to influence the recommendation. Why? Because the Guidelines inform a host of governmental nutrition programs, including National School Lunch Program and meals in the military, and also influences food-related policies and laws. A new guideline emphasizing a healthy diet pattern which is mostly plant based and low in red and processed meat may cause the meat industry a huge business loss.

The Committee’s recommendations are based on convincing scientific evidence on diet and health as well as food environments and sustainability. At the same time, the Committee’s report is purely advisory. Whether the final guideline released at the end of this year by the USDA and DHHS will include these exact recommendations remains to be seen. Although historically USDA policies have been heavily influenced by the food industry, public comments can make a difference. The Committee report is currently available on the dietary guidelines website for public comments until May 8, 2015.

Eight Ways to Prevent Cancer - in One Simple Graphic

More information and other 8IGHT WAYS pages.  

Facebook Post by Siteman Cancer Center.

Setting the Record Straight on Cancer Prevention: Lifestyle Trumps "Bad Luck"

While the paper by Tomasetti and Vogelstein is certainly intriguing and will help guide future research on targeting prevention and early detection efforts, it is still a preliminary finding and does not reverse the long-term conclusion that is supported by decades of well-designed research in people:  that cancer is largely preventable.

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It's been hard to avoid the headlines this past week touting the conclusions of a new study in the journal Science that cancer is a disease largely caused by "bad luck."  Some of these headlines have been sensationalized; some have been more measured.  Together, they've seemed nearly ubiquitous.  And in some ways that's been positive, demonstrating that cancer - and its causes and prevention - remain an important topic to both the public and the media.

Unfortunately, the conclusions of the paper - and the subsequent coverage they've received - seem to reach well beyond what the actually findings of the study support, and in doing so, have incorrectly called into question what decades of overwhelming evidence shows:  that over half of all cancers - and up to three quarters of some cancers - could be prevented by regular screening and healthy lifestyle choices.

The new study by Johns Hopkins researchers Cristian Tomasetti and Bert Vogelstein gathered data on the number of stem cell divisions that occur in various tissues in the body and compared these data to annual incidence rates of cancers in those tissues.  Stem cells divide to replace cells in tissue that die or are lost.  This maintains the tissue.  Some tissues need a lot of cell divisions for maintenance.  Others need less.  When cells divide, the DNA in cells also replicate and divide, opening up the chance for random mutations that could eventually lead to cancer.

The researchers found a strong correlation between tissues' number of stem cell divisions and cancer in those tissues, attributing 65% of cancers to these divisions, and the random DNA mutations that can occur with them.

While the study is well-designed and executed, it also has some key limitations that don't fully support its overarching conclusions.

First, the study was not done directly in humans.  It correlated data on cancer rates with tissue cell division data generated from cell analyses done in labs.  It is essentially a laboratory-based study, and lab studies in general are fantastic ways to generate hypotheses on cancer causes but bad ways to generate conclusive evidence on actual causes of cancer in humans.  The research world is littered with promising findings in petri dishes and mice that were never proved in actual people.

Second, many of the cancers included in the study are those already known to have few, if any, known lifestyle risk factors.  And while the study included two common preventable cancers, lung and colorectal, it also did not include two other major cancers with key lifestyle factors - breast and prostate cancer.  Together, lung, colorectal, breast, and prostate cancers account for approximately half of newly diagnosed cancers in the United States, a number much higher than the   other serious cancers included in the study.  The study itself even showed that colorectal cancers and lung cancers (in smokers) were less due to "bad luck" mutations than most others in the study. Other analyses based on long-term studies in humans have found that up to 75 percent of lung and colon cancers could be prevented, as well as at least half of breast cancers.

Finally, simply because there is a correlation between stem cell division and rates of cancer does not mean that random DNA mutations are the precipitating cause of cancer.  Multiple cell divisions could accelerate the cancer-causing effects of lifestyle factors. And many lifestyle factors  - from obesity to smoking - are thought to increase the risk of cancer by fostering cell division and DNA changes that begin the cascade to cancer.  So what is described as random "bad luck" may actually have its genesis in lifestyle choices.

While the paper by Tomasetti and Vogelstein is certainly intriguing and will help guide future research on targeting prevention and early detection efforts, it is still a preliminary finding and does not reverse the long-term conclusion that is supported by decades of well-designed research in people:  that cancer is largely preventable.  In our own 2012 paper that also appeared in a Science publication - Science Translational Medicine - we conclude that over half of the 572,000 deaths from cancer in the United States in 2011 were caused by key modifiable risk factors, such as smoking, obesity, and lack of physical activity.

Of course, "bad luck" plays a role in any cancer - any disease, for that matter.  We know people who smoke and drink and weigh more than they should who live until their 90s, and we know the healthiest people in the world who are struck down by disease early in life.  Healthy choices, though, can greatly increase our odds of living longer and healthier lives.  It's no guarantee, but it helps to stack the deck in our favor.

For more on the preventability of cancer, see our page: Preventing Cancer - Today

Evolution of the Science on Aspirin Use and Colon Cancer Prevention

Yesterday, we posted about a new analysis suggesting that long term aspirin use is likely to have an overall health benefit in the general population even when its side effects are taken into account.  At risk of being wonky, we wanted to follow up on that with a figure that shows the general evolution of the science on aspirin use and colon cancer prevention.  

Though it's the cardiovascular benefits that come to most people's minds when they think of reasons to take a daily aspirin, the Cuzick et al analysis shows that most of the benefits from regular aspirin use don't come from the prevention of heart attack and ischemic stroke, they actually come from the prevention of cancer - including colorectal, esophageal, and stomach cancer, and possibly breast, prostate, and lung cancer.  Of these, colorectal cancer is the most important, making up about a third of the total cancer and cardiovascular disease benefits of aspirin use.  

The figure below (full size PDF) shows the evolution of the evidence on aspirin and colon cancer prevention.  Though the science has taken a while to develop, the findings of a number of early positive studies have been confirmed in later studies, and it seems we're finally reaching a point where broad recommendations for daily aspirin use to prevent cardiovascular disease as well as cancer may become a reality.

An Aspirin a Day...May Have Overall Health Benefits

Photo: Flickr/JenR

The writing was on the wall a few years ago, but it seems that we may have finally reached a point

where the scientific evidence points pretty convincingly to the potential health benefits of long-term regular aspirin use outweighing the potential risks for most people. That's the conclusion of a new analysis appearing last week in the Annals of Oncology. 

While the heart attack and stroke benefits of aspirin use, especially in those at high risk of such events, has been accepted for years, the cancer prevention benefits have been slower to catch on - even though the evidence for colon cancer prevention alone has been quite convincing.

This new analysis confirms the cardiovascular benefits of aspirin use while solidifying its benefits in both preventing and lowering mortality for colorectal, esophageal, and stomach cancer - and possibly for breast, prostate, and lung cancer.

Bleeding is the main concern with regular aspirin use, and the analysis found - not surprisingly - that the risks of events such as bleeding strokes (hemorrhagic strokes) and GI (gastrointestinal) bleeding go up with regular use.

However, after looking at all the benefits and risks together, the researchers found that use of a daily 75 - 325 mg aspirin for 5 or more years starting between ages 50 - 65 years had overall positive benefits.

After 10 years of use, risk of cancer, heart attack, and stroke was 9 percent lower in men and 7 percent lower in women after 15 years. Lower rates of cancer made up the large majority of this benefit, with colon cancer by itself making up about a third of the total benefit from aspirin use. Taking the risks of bleeding events into account, the overall health benefit dropped to about 6 percent for men and women. Lower but still overall positive.

Of course there are still many unanswered questions about the best approach to aspirin use. Because risk of bleeding goes up with age, it's unclear at what age people should stop taking aspirin because the risks outweigh the benefits. Figuring out the best way to identify people at risk of bleeding issues is another important topic, as is the best dose to use. While there's good evidence that a low-dose baby aspirin provides most if not all the benefits of, and likely has fewer risks than, a higher dose 325 mg aspirin, there are not yet definitive studies that have looked at the issue.

While anyone interested in starting on daily aspirin should first talk with his or her doctor, the data are now clearer than they've ever been that such use is likely to have real and lasting health benefits for most people.

Related post: Evolution of the Science on Aspirin Use and Colon Cancer Prevention