Could This Diet Raise your Risk of Colon Cancer?

A pro-inflammatory diet replete in red, processed, and organ meat, among other foods, increases the risk for colorectal cancer (CRC) in both men and women. It is especially risky in overweight and obese men, and, paradoxically, also in lean women.

Today, we turn again to ways you can use your diet to reduce your risk of cancer; more specifically, we will focus on the harm of a so-called pro-inflammatory diet. Researchers at the Harvard T.H. Chan School of Public Health (USA) reported two provocative findings this week in the online issue of JAMA Oncology. Let’s cut to the chase and tell you what you need to know. There were two major findings from this study: 1) Higher dietary inflammatory potential was associated with an increased risk of developing colon or rectal cancer among both men and women; and 2) the risk of colon or rectal cancer appeared even higher amongst overweight and obsessive men and in lean women and among men and women not consuming alcohol.

The team rated 18 food groups for their inflammatory potential, using a score based on three inflammatory biomarkers (interleukin-6, C-reactive protein, and tumor necrosis factor-alpha receptor 2. They then rated diets on a continuum from a maximally anti-inflammatory diet to a maximally pro-inflammatory one. Foods that raised the concentrations of these inflammatory markers included tomatoes; high- and low-energy carbonated beverages; vegetables other than green leafy and dark yellow vegetables, and processed or red meat, organ meat, and fish other than dark-meat fish. On the other hand, beer, wine, tea, coffee, dark yellow and dark yellow vegetables, snacks, fruit juice, and pizza were inversely related to concentrations of these same inflammatory markers.

The bottom line? Colorectal cancer risk was nearly 1.5-times higher among overweight or obese men with the most pro-inflammatory diets, as compared to those with the least inflammatory diets. Even lean women had a higher risk with the pro-inflammatory diet, with the chances for getting colorectal cancer rising by a factor of 1.31.

The alcohol finding is puzzling, as it is in contrast to many previous studies in which alcohol raised cancer risk. It may be that alcohol increases that risk through mechanisms unrelated to inflammation.

So, you may be able to reduce your own chances of getting colorectal cancer. Multiple studies have shown a baby aspirin reduces the risk, perhaps partly through inhibition of inflammation. Now, we know that diet can similarly affect your state of inflammation, perhaps independently of the aspirin effect. Finally, if you are at higher risk of colorectal cancer (say, a family member had the disease, or through some personal risk factors), please discuss other potential interventions (e.g. more frequent colonoscopy; consideration of a baby aspirin daily). And all of us should check in with our healthcare provider to see when we are due for a colonoscopy. And yes, I am personally overdue! I’m Dr. Michael Hunter.

Wanna learn more? Click here to explore my new site, devoted to wellness: Wellness!

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JAMA Oncol. Published online January 18, 2018.

Medscape Oncology 2018

Poor adolescent diet associated with premenopausal breast cancer

“During adolescence and early adulthood, when the mammary gland is rapidly developing and is therefore particularly susceptible to lifestyle factors, it is important to consume a diet rich in vegetables, fruit, whole grains, nuts, seeds, and legumes and to avoid soda consumption and a high intake of sugar, refined carbohydrates, and red and processed meats.”

– lead author Karin B. Michels, ScD, PhD, professor and chair of the Department of Epidemiology at the UCLA Fielding School of Public Health, Los Angeles

Key points: Women who consumed a diet associated with chronic inflammation  as adolescents or young adults appear to have a higher risk of developing premenopausal breast cancer, as compared with those who had a diet not linked to inflammation.

Background: Researchers used data from 45,204 women in the Nurses’ Health Study II who had completed a food frequency questionnaire in 1998, when they were ages 33 to 52, about their diet during high School. The investigators then assed adult diet by first using a food frequency questionnaire in 1991, when participants were ages 27 to 44, and then every 4 years thereafter. They gave each woman’s diet an inflammatory score using a previously method that links diet with inflammatory markers in the blood.

During 22 years of follow-up, 870 of the women who completed the high school food frequency questionnaire were diagnosed with premenopausal breast cancer and 490 were diagnosed with postmenopausal breast cancer. When women were divided into five groups based on the inflammatory score of their adolescent diet, those in the highest score group had a 35 percent higher risk for premenopausal breast cancer relative to those in the lowest score group. When the same analysis was done based on early adulthood diet, those in the highest inflammatory score group had a 41 percent higher risk for premenopausal breast cancer relative to those in the lowest score group.

I’m Michael Hunter, the Breast Cancer Doctor.

How Can You Reduce Your Risk of Getting Cancer?

Recent reports suggest that about 2 out of 3 cancers may be due to “bad luck.” Today, we focus on the other third: What can you do to reduce your risk of cancer?

What You Need to Know:

  • Maintaining a healthy body weight and being physically active had the greatest impact on overall risk of a cancer-related death. 
  • Restricting alcohol consumption to one drink per day for women and two drinks per day for men was associated with 29% reduced risk for obesity-related cancers. Additionally, the risk was up to 71% lower for the most common site-specific cancers in the United States (breast, prostate, and colorectal).

Background

  • As people make their resolutions for 2015, two new studies — which show that curbing alcohol consumption, adding more plant foods to the diet, and losing excess weight can help reduce the risk of developing cancer — serve as a reminder that a healthy lifestyle is important.
  • In 1997, the World Cancer Research Fund (WCRF) and the American Institute for Cancer Research (AICR) issued cancer prevention guidelines for weight management, diet, and physical activity. These were updated in 2007 and are considered to be the most comprehensive scientific analysis of cancer prevention and causation ever undertaken. Specifically, the guidelines reported that excess body fat is associated with an increased cancer risk and that there is convincing evidence that the consumption of alcohol, red meat, and processed meat elevates cancer risk. Since that time, numerous studies have reported links between colorectal cancer risk and alcohol, between breast cancer mortality and obesity, between breast cancer relapse and obesity, and between breast cancer risk and red meat.

The Evidence: The first study, published online January 6 in Cancer Causes & Control, showed that eating a plant-based diet and limiting alcohol intake, both already included in various cancer prevention guidelines, could help cut the risk for obesity-related cancers (about a third of all of cancers). In a cohort of nearly 3000 adults, the researchers found that restricting alcohol consumption to one drink per day for women and two drinks per day for men was associated with 29% reduced risk for obesity-related cancers. Additionally, the risk was up to 71% lower for the most common site-specific cancers in the United States (breast, prostate, and colorectal). For individuals who consume starchy vegetables, such as corn, potatoes, and yams, sufficient consumption of nonstarchy legumes, fruits, and vegetables was associated with a reduction in the risk for colorectal cancer.

Pronounced Effect on Cancer Risk

In their study, Makarem and colleagues investigated whether the healthful behaviors outlined in the WCRF/AICR guidelines were associated with the risk for obesity-related cancers, in particular, breast, prostate, and colorectal cancer. Of the 2983 adults enrolled in the Framingham Offspring cohort from 1991 to 2008, the researchers identified 480 incident obesity-related cancers.

Data from food frequency questionnaires, anthropometric measures, and self-reported physical activity were used to develop a 7-component score based on recommendations for body fatness; physical activity; foods that promote weight gain; plant foods; animal foods; alcohol; and food preservation, processing, and preparation. The cohort was, on average, middle aged to older and overweight, but had a relatively high level of physical activity. The mean duration of follow-up was 11.5 years.

The overall score was not associated with obesity-related cancer risk after adjustment for confounders such as age, sex, smoking, energy, and pre-existing conditions (hazard ratio [HR], 0.94; 95% confidence interval [CI], 0.86 – 1.02). However, when the score components were considered separately, the researchers found that for every unit increment in the alcohol score (representing an improvement and more closely meeting the guideline recommendations), there was 29% lower risk for obesity-related cancers (HR, 0.71; 95 % CI, 0.51 – 0.99) and a 49% to 71% reduced risk for breast, prostate, and colorectal cancers.

Similarly, each unit increment in the subcomponent score for nonstarchy plant foods (fruits, vegetables, and legumes) for those who eat starchy vegetables was associated with a 66% lower risk for colorectal cancer (HR, 0.44; 95% CI, 0.22 – 0.88).

Healthy Body Weight and Exercise Reduce Mortality

The second study, published online January 7 in the American Journal of Clinical Nutrition, reported similar results. Researchers found that greater adherence to the cancer prevention guidelines of the American Cancer Society (ACS) was associated with a reduction not only in cancer incidence, but also in cancer mortality and total mortality.

The ACS guidelines recommend that individuals avoid smoking, achieve and maintain a healthy weight, be physically active, and eat a healthy diet that emphasizes plant foods. In their study, Geoffrey Kabat, PhD, senior epidemiologist in the Department of Epidemiology & Population Health at the Albert Einstein College of Medicine in Bronx, New York, and colleagues report that maintaining a healthy body weight and being physically active had the greatest impact on overall mortality for both men and women.

The researchers used data from the NIH-AARP Diet and Health Study, a prospective cohort study of 566,401 adults who were 50 to 71 years of age in 1995 and 1996, when they enrolled in the study. They were followed for a median of 10.5 years for cancer incidence, 12.6 years for cancer mortality, and 13.6 years for total mortality.

During the study period, there were 73,784 cases of cancer, 16,193 cancer deaths, and 81,433 deaths from any cause. The patients were stratified by how closely they adhered to ACS guidelines, and adherence to the guidelines was associated with a reduced risk for all cancers combined. When the highest level of adherence was compared with the lowest level, the hazard ratio was 0.90 for men and 0.81 for women.

In addition, increased adherence was associated with a reduction in risk for 14 of 25 specific cancers. Reduction in the risk for gallbladder cancer was 65% in men and women combined, for endometrial cancer was 60%, for liver cancer was 48% in men, for colon cancer was 48% in men and 35% in women, and for rectal cancer was 40% in men and 36% in women.

My Take: These results add to the existing evidence on the potential role of limiting alcohol intake and increasing the intake of plant foods in influencing cancer risk. Dietary advice on cancer should focus on encouraging the consumption of a plant-based diet providing abundant non-starchy fruits, vegetables, and legumes, and restricting alcohol, if consumed at all, to the recommended levels. Try to stick to the ACS Guidelines, as the closer you follow them, the greater the benefit in cancer risk-reduction. Finally, exercise and don’t use tobacco. I’m Dr. Michael Hunter.

References: Cancer Causes Control. Published online January 6, 2015. Abstract; Am J Clin Nutr. Published online January 7, 2015. Abstract; http://www.medscape.com/viewarticle/837976#vp_2

Lower Your Breast Cancer Recurrence Risk

What You Need to Know: Patients with breast cancer who reduced their dietary fat intake for 5 years after a diagnosis of hormone-unrelated early-stage breast cancer had signficantly reduced all-cause death rates, according to data from the Women’s Intervention Nutrition Study (WINS) presented at the 2014 San Antonio Breast Cancer Symposium.

The Study: For WINS, a randomized trial, Dr. Chlebowski and colleagues recruited 2,437 women ages 48 to 79 years with early-stage breast cancer receiving standard-of-care treatments at 39 centers in the United States. Of them, 1,597 had ER-positive breast cancer, 478 had ER-negative breast cancer, and 362 had ER/PR-negative breast cancer. Within 6 months of diagnosis, subjects were randomly assigned either to a dietary intervention group (n=975; 205 with negative cancer, and 147 ER/PR-negative cancer) or to a control group (n=1,462; 273 ER-negative cancer, and 215 ER/PR-negative cancer).

The dietary intervention was centered on a goal of lowering fat intake for 5 years while maintaining nutritional adequacy. Centrally trained, registered dieticians implementing a low-fat eating plan, gve women in the intervention group a fat gram goal, and the women underwent 8 biweekly individual counseling sessions with subsequent contacts every 3 months. Subjects also self-monitored their fat/gram intake using a “keeping score” book. Fat intake was externally monitored by unannounced annual 24-hour telephone recalls done.

“The current findings with respect to long-term influence of dietary lifestyle intervention on overall survival are mixed, but of potential importance,” said Rowan Chlebowski, MD, PhD, medical oncologist at the Los Angeles Biomedical Research Institute at the Harbor-UCLA Medical Center. “In a prior report of WINS after 5-years’ follow-up, relapse events were 24% lower in the intervention group. In the current report, the intervention influence on long-term survival was examined. Overall, while the death rate was somewhat lower in the intervention group compared with control group (13.6% versus 17%, respectively), the difference was not statistically significant. However, in exploratory subgroup analyses, in women with estrogen receptor [ER]-negative cancers, a 36 percent, statistically significant reduction in deaths was seen in women in the intervention group,” said Dr. Chlebowski.

  • In women with cancers that were both ER- and progesterone receptor [PR]-negative, the reduction was even more significant (56%), Dr. Chlebowski added.
  • After 5 years of dietary intervention, researchers found that fat calories were lowered by 9.2% and body weight was lowered by nearly 6 pounds in the intervention group, compared with the control group.

“HER2 evaluation was not available when this study was conducted, but it is likely that a substantial number of ER/PR-negative breast cancers were also negative for HER2, making them triple-negative breast cancers, which generally have a poor prognosis,” said Dr. Chlebowski. “The signal that perhaps a lifestyle intervention targeting dietary fat intake associated with weight loss could substantially increase the chances of survival for a woman with triple-negative breast cancer could influence this group of patients.”

My Take: It is wonderful that we have an increasing body of evidence that dietary manipulation may lower your risk of recurrence. The drop is not small: It is more than half for those whose tumors are not driven by either estrogen or progesterone. In addition, you may lower your risk of heart attack, stroke, other cancers, and a myriad of other medical problems. Researchers in this study supported the dietary intervention for a median of 5 years. Aim for a lifelong change rather than be a short-term alteration in your diet. I’m Dr. Michael Hunter.

Reference: 37th San Antonio Breast Cancer Symposium (December, 2014); San Antonio, TX

Fight Prostate Cancer with a Tomato-Rich Diet

What You Need to Know: New research suggests that men who eat over 10 portions a week of tomatoes have an 18 percent lower risk of developing prostate cancer. Prostate cancer is the second most common cancer in men worldwide. Rates are higher in developed countries, which some experts believe is linked to a Westernised diet and lifestyle.

The Evidence:  To assess if following diet and lifestyle recommendations reduces risk of prostate cancer, researchers at the Universities of Bristol, Cambridge and Oxford (England) looked at the diets and lifestyles of 1,806 men aged between 50 and 69 with prostate cancer and compared them with 12,005 cancer-free men. The study is the first study of its kind to develop a prostate cancer ‘dietary index’ which consists of dietary components — selenium, calcium and foods rich in lycopene — that have been linked to prostate cancer.

Men who had optimal intake of these three dietary components had a lower risk of prostate cancer. Tomatoes and its products — such as tomato juice and baked beans — were shown to be most beneficial, with an 18 per cent reduction in risk found in men eating over 10 portions a week.

My Take: The reduction in risk may be due to lycopene, an antioxidant that makes tomatoes and watermelon red in color. Lycopenes may help fight off toxins that can cause damage to your DNA (genes). Tomatoes may reduce the risk of prostate cancer among men, and should be considered as a part of a diet containing a wide variety of fruits, vegetables, and fiber. And don’t forget the physical activity and maintenance of a good weight (e.g. body mass index 20-25). I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad: Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: V. Er, J. Athene Lane, R. M. Martin, P. Emmett, R. Gilbert, K. N. L. Avery, E. Walsh, J. L. Donovan, D. E. Neal, F. C. Hamdy, M. Jeffreys. Adherence to dietary and lifestyle recommendations and prostate cancer risk in the Prostate Testing for Cancer and Treatment (ProtecT) trial. Cancer Epidemiology Biomarkers & Prevention, 2014; DOI: 10.1158/1055-9965.EPI-14-0322

 

 

Breast Cancer Spread: Can Dieting Reduce Risk?

overweight obese woman

What You Need to Know: Women with an aggressive subtype of breast cancer known as “triple negative” may be able to reduce the chance of disease spreading distantly by reducing their calorie intake. But… the data thus far is based on mice (and not human) studies.

Well, it does work for mice: The study published in the Journal Breast Cancer Research and Treatment, used mice models to investigate the impact of diet on triple negative disease, which is found in about one in five women with breast cancer. It found that when mice were given 30 per cent fewer calories, changes occurred in the body in the way cells were regulated. Mice on restricted diets produced more protective proteins in the tissues around the tumour, which make it harder for cancer to spread, the study by Thomas Jefferson University found.

My Take: We know that in among some groups of women (for example, women who are post-menopausal), obesity increases the risk of breast cancer. Unfortunately, treatment such as chemotherapy (and steroids) can cause weight gain. This weight gain can lead to worse cancer outcomes. Human trials are examining the impact of calorie restriction on outcomes. For now, I advise my patients to try to achieve, and maintain, an optimal Body Mass Index (BMI) of 20 to 25. I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad: Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: http://www.telegraph.co.uk/journalists/laura-donnelly/10856597/Dieting-may-reduce-chance-of-cancer-spread.html#source=refresh:

For Oral Health, Have a Tea Party

green tea cup and plants

Epidemiological studies evaluating the association of tea consumption and the risk of oral cancer risk have produced inconsistent results. Thus, the authors of a recent study conducted a meta-analysis (study of studies) to assess the relationship between tea consumption and oral cancer risk.

METHODS: Pertinent studies were identified by a search in PubMed, Web of Knowledge and Wan Fang Med Online. The fixed or random effect model was used based on heterogeneity test. Publication bias was estimated using Egger’s regression asymmetry test.

RESULTS: 14 articles with 19 studies comprising 4675 oral cancer cases were included in this meta-analysis. The relative risk (95% confidence interval) of oral cancer for the highest versus the lowest category of tea consumption was 0.853 (0.779-0.934), and the association was significant between oral cancer risk and green tea consumption [0.798 (0.673-0.947)] but not in the black tea consumption [0.953 (0.792-1.146)]. [This implies that you can reduce the risk by about 1/5th if you consume green tea.]

TAKE-AWAY MESSAGE: Tea consumption may have a protective effect on oral cancer, especially green tea consumption. Previous studies suggested that coffee may lower the risk of cancer of the mouth region, but now we know green tea may work, too! Obviously, more research is needed, but the link seems logical. I’m Dr. Michael Hunter.

The small print: The material presented herein is informational only, and is not designed to provide specific guidance for an individual. Please check with a valued health care provider with any questions or concerns. As for me, I am a Harvard- , Yale- and UPenn-educated radiation oncologist, and I practice in the Seattle, WA (USA) area. I feel genuinely privileged to be able to share with you. If you enjoyed today’s offering, please consider clicking the follow button at the bottom of this page.

Available now: Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Both can be found at the Apple Ibooks store. Coming Soon for iPad:  Understand Breast Cancer in 60 Minutes; Understand Colon Cancer in 60 Minute; Understand Colon Cancer in 60 Minutes; Understand Brain Glioma in 60 Minutes. Thank you.

Reference: Oral Oncol. 2014 Jan 2. pii: S1368-8375(13)00802-6. doi: 10.1016/j.oraloncology.2013.12.014. [Epub ahead of print]