Weekly Health Update: breast cancer

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Sunday, November 28, 2010

Mammograms Save Lives in Women with Family History of Breast Cancer

Weekly Health Update:

Mammograms Save Lives in Women with

Family History of Breast Cancer

"A critical weekly review of important new research findings for health-conscious readers..."

By, Robert A. Wascher, MD, FACS

Updated: 11/28/2010

The information in this column is intended for informational purposes only, and does not constitute medical advice or recommendations by the author. Please consult with your physician before making any lifestyle or medication changes, or if you have any other concerns regarding your health.

Welcome to Weekly Health Update

“A critical weekly review of important new research findings for health-conscious readers”

MAMMOGRAMS SAVE LIVES IN WOMEN WITH FAMILY HISTORY OF BREAST CANCER

While the debate about whether or not routine screening mammograms can save lives continues in some circles, the clinical research evidence supporting mammograms as a lifesaving cancer screening exam continues to accumulate. Now, a newly published public health study, which appears in The Lancet Oncology, examines the survival benefit associated with routine screening mammograms in women who have a family history of breast cancer.

In this large multicenter prospective clinical research study, which was performed in the UK, 6,710 women between the ages of 40 and 42 were enrolled in this study, and were followed for an average of about 4 years. These women, who had at least some family history of breast cancer, underwent annual screening mammograms as part of this clinical research study. This study used two important control groups to assess the impact of regular annual screening mammograms on the risk of mortality in these young women. The first control group consisted of women who were at average risk for breast cancer (these women, themselves, served as the control group for the enormous UK Age Trial, which included more than 106,000 patient volunteers, and which recently reported a 10-year follow-up of its results). The second control group, against which these 6,710 women with an intermediate familial risk of breast cancer were compared, included young women from another large public health study that was performed in the Netherlands.

Among the 136 women who were diagnosed with breast cancer during the relatively brief course of this ongoing study, 77 percent were diagnosed by screening mammography, while 21 percent were diagnosed when they presented with a new breast lump (or with other clinical signs or symptoms of breast cancer). (Another 2 percent of patients failed to attend their scheduled screening mammograms, and subsequently developed clinical signs or symptoms of breast cancer.)

In this study (and as other studies have shown, even among women who are at average risk of developing breast cancer), breast cancers that were detected by annual screening mammograms were significantly smaller in size, and significantly less likely to be associated with the spread of cancer to the lymph nodes. In addition to these very important breast cancer prognostic factors, women who were diagnosed with breast cancer as a result of annual screening mammograms had much less aggressive appearing tumors under the microscope when compared to women who were diagnosed with breast cancer only after a lump, or other signs of breast cancer, appeared.

Based upon the findings of this newly published study, young women with even an intermediate risk of breast cancer, based upon having one or more relatives with breast cancer, were 20 percent less likely to die within 10 years when compared with a poorly screened, or unscreened, average-risk population of young women. Moreover, this survival advantage appeared to be directly related to annual screening mammograms, once all other breast cancer risk factors among these three populations of women had been considered.

For a complete discussion of the compelling scientific evidence linking routine screening mammograms with a decreased risk of death due to breast cancer, please see the extended clinical section on breast cancer in my new book, A Cancer Prevention Guide for the Human Race.

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Disclaimer: As always, my advice to readers is to seek the advice of your physician before making any significant changes in medications, diet, or level of physical activity

Dr. Wascher is an oncologic surgeon, professor of surgery, cancer researcher, oncology consultant, and a widely published author

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Robert A. Wascher, MD, FACS

Dr. Wascher's Archives:

11-28-2010: Mammograms Save Lives in Women with Family History of Breast Cancer

11-14-2020: Low Dose Aspirin Reduces Colorectal Cancer Risk

11-7-2010: Coffee, Tea, Caffeine and Brain Cancer Risk

10-28-2010: Diet and Lifestyle Habits that Decrease Colorectal Cancer Risk

10-21-2010: The Silent Epidemic of Surgeon Burnout and Depression

10-14-2010: Gum Disease (Gingivitis) and Breast Cancer Risk

10-7-2010: Hormone Replacement Therapy (HRT) and Breast Cancer Risk

10-3-2010: Mammograms Between 40 and 49 Years of Age

9-26-2010: Vitamin D, Cardiovascular Disease, Cancer, and Death

9-19-2010: Fruits and Vegetables Improve Memory

9-12-2010: Low-Carb Diet and Risk of Death

9-5-2010: Non-Compliance with Hormonal Therapy for Breast Cancer and Risk of Death

8-29-2010: New Treatment for Irritable Bowel Syndrome (IBS)

8-22-2010: Lactoferrin Reduces Abdominal (Visceral) Obesity

8-15-2010: Blueberries, Obesity, Diabetes and Metabolic Syndrome

8-8-2010: High LDL Cholesterol in Young Adults and Heart Disease Risk in Middle Age

8-1-2010: Physician Error

7-25-2010: Obesity and Cancer Risk

7-18-2010: Vitamin D Reduces Risk of Cognitive Decline & Dementia

7-11-2010: All Forms of Hormone Replacement Therapy (HRT) Increase Breast Cancer Risk

7-4-2010: Irritable Bowel Syndrome: Cause Discovered?

6-27-2010: Soy, Curcumin & Prostate Cancer Risk

6-20-2010: Green Tea Epicatechin Reduces Heart Damage & CHF

6-13-2010: Diacylglycerol (Diglyceride) Oil Reduces Obesity

6-6-2010: Important New Advance in the Breast Cancer Treatment: Intraoperative Radiation Therapy

5-30-2010: Medical Research Studies & “Spin”

5-23-2010: Soy & Curcumin Reduce Prostate-Specific Antigen (PSA)

5-16-2010: Coffee & the Risk of Death from Heart Disease & Cancer

5-9-2010: Soy Foods & Stomach Cancer Risk

5-2-2010: Chemotherapy for Breast Cancer & Memory Loss

4-25-2010: Smoking, Teenagers & Tobacco Company Advertising

4-18-2010: Coffee Improves HDL Cholesterol Levels

4-11-2010: Cruciferous Vegetables, Soy & Breast Cancer Risk

4-4-2010: Avodart (Dutasteride) & Prostate Cancer Prevention

3-28-2010: Aspirin & Breast Cancer Survival

3-21-2010: Obesity, Alcohol & Liver Disease

3-14-2010: Nuts, Diet & Obesity

3-7-2010: Walnuts, Cholesterol, LDL & Triglycerides

2-28-2010: Soy Isoflavones & Recurrent Prostate Cancer

2-21-2010: Testosterone Supplements in Frail Elderly Men

2-14-2010: Pancreatic Cancer Risk, Sodas & Juice

2-7-2010: Vitamin D, Cardiovascular Disease & Death

1-31-2010: Concord Grape Juice Improves Memory

1-24-2010: Mozart, Music, Babies & Health

1-17-2010: Breast Cancer, Physical Therapy & Lymphedema

1-10-2010: Prevention of Surgical Site Infections (SSIs) after Surgery

1-3-2010: Ginkgo Biloba, Memory & Cognitive Health

12-20-2009: CT Scans & Cancer Risk

12-13-2009: Soy Isoflavones Decrease Breast Cancer Recurrence Risk

12-6-2009: Salt (Sodium) Intake, Stroke & Cardiovascular Disease

11-29-2009: Exercise & Prostate Cancer Risk

11-22-2009: Genistein (Soy Isoflavone) & Prostate Cancer

11-15-2009: Breast Cancer Treatment & Chronic Pain

1-8-2009: Vitamin D & Breast Cancer Risk

11-1-2009: Exercise & Prostate Cancer Risk

10-25-2009: HPV Virus & Risk of Breast Cancer

10-18-2009: Post-Cholecystectomy Syndrome (Symptoms after Gallbladder Surgery)

10-11-2009: Vitamin D & Falls in the Elderly

10-4-2009: Surgery, NSQIP, Complications & Death

9-27-2009 Stress, Heart Disease, Exercise & Death

9-20-2009: Vitamin D & Colorectal Cancer Survival

9-13-2009: H1N1 Swine Flu Update

9-7-2009: Green Tea, Aging & Lifespan

8-30-2009: Irritable Bowel Syndrome (IBS), Diet & Fiber

8-23-2009: Update on Prostate Cancer and Cryotherapy

8-16-2009: Exercise Improves Lymphedema Symptoms in Breast Cancer Survivors

8-9-2009: Breast Cancer Recurrence, Death & Vitamin D

8-2-2009: Honesty, Dishonesty & Brain Function

7-26-2009: Coronary Artery CT Scans & Cancer Risk

7-19-2009: Hormone Replacement Therapy (HRT) & Ovarian Cancer

7-12-2009: Breast Cancer & Metformin (Glucophage)

7-5-2009: Prostate Cancer & Green Tea

6-28-2009: Air Pollution & the Risk of Deep Venous Thrombosis (DVT)

6-21-2009: Red Yeast Rice, Statins & Cholesterol

6-14-2009: Bone Marrow Stem Cell Transplant & Congestive Heart Failure (CHF)

6-7-2009: Diet, Soy & Breast Cancer Risk

5-31-2009: Diet and Prostate Cancer Risk

5-24-2009: Diabetes, Glucose Control & Death

5-17-2009: Drug Company Marketing & Physician Prescribing Bias

5-10-2009: Hemorrhoids & Surgery

5-3-2009: Statin Drugs & Blood Clots (Thromboembolism)

4-26-2009: Are We Really Losing the War on Cancer?

4-19-2009: Exercise in Middle Age & Risk of Death

4-12-2009: Can Chronic Stress Harm Your Heart?

4-5-2009: Does PSA Testing for Prostate Cancer Save Lives?

3-22-2009: CABG Surgery vs. PCI in Diabetics with Coronary Artery Disease; Sweetened Beverages and Coronary Artery Disease

3-15-2009: Depression, Stress, Anger & Heart Disease

3-8-2009: Coronary Artery Disease: CABG vs. Stents?; Swimming Lessons & Drowning Risk in Children

3-1-2009: Aspirin & Colorectal Cancer Prevention; Fish Oil & Respiratory Infections in Children

2-22-2009: Health Differences Between Americans & Europeans; Lycopene & Prostate Cancer

2-15-2009: Statin Drugs & Death Rates; Physical Activity, Breast Cancer & Sex Hormones

2-8-2009: Hormone Replacement Therapy (HRT) & Breast Cancer; Stool DNA Testing & Cancer of the Colon & Rectum

2-1-2009: Obesity and the Complications of Diverticulosis (Diverticulitis & Bleeding); Obesity, Weight Loss & Urinary Incontinence

1-25-2009: Prostate Cancer, Fatigue & Exercise; Does your Surgeon “Warm-up” Before Surgery?

1-18-2009: Cancer and Vitamins; Teenagers, MySpace and Risky Behaviors

1-11-2009: Exercise Reverses Some Effects of Fatty Meals; Vitamin C and Blood Pressure

1-4-2009: Secondhand Smoke & Heart Attack Risk; Poor Physical Fitness During Childhood & Heart Disease Risk During Adulthood

12-28-2008: Stress & Your Risk of Heart Attack; Vitamin D & the Prevention of Colon & Rectal Polyps

12-21-2008: Breast Cancer Incidence & Hormone Replacement Therapy; Circumcision & the Risk of HPV & HIV Infection

12-14-2008: Vitamin E, Vitamin C and Selenium Do Not Prevent Cancer; Postscript: A Possible Cure for Down’s Syndrome

12-7-2008: Generic vs. Brand-Name Drugs, Stress & Breast Cancer Survival

11-30-2008: A Possible Cure for Down’s Syndrome?; Smoking & Cognitive Decline; Calcium & Vitamin D & Breast Cancer Risk

11-23-2008: Breast Cancer & Fish Oil; Lymphedema after Breast Cancer Treatment; Vasectomy & Prostate Cancer Risk

11-16-2008: Vitamin E & Vitamin C: No Impact on Cardiovascular Disease Risk; Does Lack of Sleep Increase Stroke & Heart Attack Risk in Hypertensive Patients?

11-9-2008: Statins Cut Heart Attack Risk Even with Normal Cholesterol Levels; Statins & PSA Level

11-2-2008: Radiation Treatment of Prostate Cancer & Second Cancers; Sexual Content on TV & Teen Pregnancy Risk

10-26-2008: Smoking & Quality of Life

10-19-2008: Agent Orange & Prostate Cancer

10-12-2008: Pomegranate Juice & Prostate Cancer

10-5-2008: Central Obesity & Dementia; Diet, Vitamin D, Calcium, & Colon Cancer

9-28-2008: Publication & Citation Bias in Favor of Industry-Funded Research?

9-21-2008: Does Tylenol® (Acetaminophen) Cause Asthma?

9-14-208: Arthroscopic Knee Surgery- No Better than Placebo?; A Healthy Lifestyle Prevents Stroke

8-23-2008: Alcohol Abuse Before & After Military Deployment; Running & Age; Running & Your Testicles

8-12-2008: Green Tea & Diabetes; Breastfeeding & Adult Cholesterol Levels; Fish Oil & Senile Macular Degeneration

8-3-2008: Exercise & Weight Loss; Green Tea, Folic Acid & Breast Cancer Risk; Foreign Language Interpreters & ICU Patients

7-26-2008: Viagra & Sexual Function in Women; Patient-Reported Adverse Hospital Events; Curcumin & Pancreatic Cancer

7-13-2008: Erectile Dysfunction & Frequency of Sex; Muscle Strength & Mortality in Men; Cryoablation for Prostate Cancer

7-6-2008: Sleep, Melatonin & Breast Cancer Risk; Mediterranean Diet & Cancer Risk; New Treatment for Varicose Veins

6-29-2008: Bone Marrow Stem Cells & Liver Failure; Vitamin D & Colorectal Cancer Survival; Green Tea & Colorectal Cancer

6-22-2008: Obesity, Lifestyle & Heart Disease; Effects of Lifestyle & Nutrition on Prostate Cancer; Ginkgo Biloba, Ulcerative Colitis & Colorectal Cancer

6-15-2008: Preventable Deaths after Coronary Artery Bypass Graft (CABG) Surgery; Green Tea & Colorectal Cancer; Attention-Deficit/Hyperactivity Disorder (ADHD) & St. John’s Wort

6-8-2008: Vitamin D & Prostate Cancer Risk; Radiofrequency Ablation (RFA) of Kidney (Renal) Cancer; Antisense Telomerase & Cancer

6-2-2008: Acute Coronary Syndrome- Do You Know the Symptoms?; Green Tea & Lung Cancer; Episiotomy & Subsequent Deliveries- An Unkind Cut

5-25-2008: Early Childhood Screening Predicts Later Behavioral Problems; Psychiatric Disorders Among Parents of Autistic Children; Social & Psychiatric Profiles of Young Adults Born Prematurely

5-18-2008: Can Statins Reverse Coronary Artery Disease?; Does Breast Ultrasound Improve Breast Cancer Detection?; Preventive Care Services at Veterans Administration (VA) Medical Centers

5-11-2008: Smoking Cessation & Risk of Death; Childhood Traumas & Adult Suicide Risk; “White Coat Hypertension” & Risk of Cardiovascular Disease

5-4-2008: Super-Size Me: Fast Food’s Effects on Your Liver; Exercise, Weight & Coronary Artery Disease; Contamination of Surgical Instruments in the Operating Room

4-27-2008: Stents vs. Bypass Surgery for Coronary Artery Disease; The “DASH” Hypertension Diet & Cardiovascular Disease Prevention; Testosterone Therapy for Women with Decreased Sexual Desire & Function

4-20-2008: BRCA Breast Cancer Mutations & MRI Scans; Bladder Cancer Prevention with Broccoli?; Diabetes: Risk of Death Due to Heart Attack & Stroke

4-13-2008: Breast Cancer Recurrence & Hormone Replacement Therapy (HRT); Carotid Artery Disease: Surgery vs. Stents?; Statin Drugs & Cancer Prevention

4-6-2008: Human Papilloma Virus (HPV), Pap Smear Results & Cervical Cancer; Human Papilloma Virus (HPV) Infection & Oral Cancer; Hormone Replacement Therapy (HRT) & the Risk of Gastroesophageal Reflux Disorder (GERD)

3-30-2008: Abdominal Obesity & the Risk of Death in Women; Folic Acid Pretreatment & Heart Attacks; Pancreatic Cancer Regression after Injections of Bacteria

3-23-2008: Age of Transfused Blood & Risk of Complications after Surgery; Obesity, Blood Pressure & Heart Size in Children

3-16-2008: Benefits of a Full Drug Coverage Plan for Medicare Patients?; Parent-Teen Conversations about Sex; Soy (Genistein) & Prostate Cancer

3-9-2008: Flat Colorectal Adenomas & Cancer; Health Risks after Stopping Hormone Replacement Therapy (HRT); Television, Children & Obesity

3-2-2008: Medication & Risk of Death After Heart Attack; Hormone Replacement Therapy (HRT) & Mammogram Results; Selenium: Cancer, Heart Disease & Death

2-23-2008: Universal Healthcare Insurance Study; Glucosamine & Arthritis

2-17-2008: Exceptional Longevity in Men; Testosterone & Risk of Prostate Cancer; Smoking & Pre-malignant Colorectal Polyps

2-10-2008: Thrombus Aspiration from Coronary Arteries; Intensive Management of Diabetes & Death; Possible Cure for Down's Syndrome?

2-3-2008: Vitamin D & Cardiovascular Health; Vitamin D & Breast Cancer; Green Tea & Colorectal Cancer

1-27-2008: Colorectal Cancer, Esophageal Cancer & Pancreatic Cancer: Update from the 2008 American Society of Clinical Oncology's Gastrointestinal Cancers Symposium

1-20-2008: Testosterone Levels & Risk of Fractures in Elderly Men; Air Pollution & DNA Damage in Sperm; Statins & Trauma Survival in the Elderly

1-12-2008: Statins, Diabetes & Stroke and Obesity; GERD & Esophageal Cancer

1-7-2008: Testosterone Supplements in Elderly Men; Colorectal Cancer-- Reasons for Poor Compliance with Screening Recommendations

12-31-2007: Minority Women, Hormone Replacement Therapy & Breast Cancer; Does Health Insurance Improve Health?

12-23-2007: Is Coffee Safe After a Heart Attack?; Impact of Divorce on the Environment; Hypertension & the Risk of Dementia; Emotional Vitality & the Risk of Heart Disease

12-16-2007: Honey vs. Dextromethorphan vs. No Treatment for Kids with Night-Time Cough, Acupuncture & Hot Flashes in Women with Breast Cancer, Physical Activity & the Risk of Death, Mediterranean Diet & Mortality

12-11-2007: Bias in Medical Research; Carbon Nanotubes & Radiofrequency: A New Weapon Against Cancer?; Childhood Obesity & Risk of Adult Heart Disease

12-2-2007: Obesity & Risk of Cancer; Testosterone Level & Risk of Death; Drug Company Funding of Research & Results; Smoking & the Risk of Colon & Rectal Cancer

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Monday, December 14, 2009

Soy Isoflavones Decrease Breast Cancer Recurrence Risk

Weekly Health Update:

Soy Isoflavones Decrease Breast Cancer Recurrence Risk

"A critical weekly review of important new research findings for health-conscious readers..."

By, Robert A. Wascher, MD, FACS

Updated: 12/13/2009

Welcome to Weekly Health Update

“A critical weekly review of important new research findings for health-conscious readers”

SOY ISOFLAVONES REDUCE BREAST CANCER RECURRENCE RISK

Regular readers of this column are already aware of the controversy surrounding soy isoflavone intake and breast cancer risk. As happens frequently in clinical research (unfortunately), contradictory research findings have made it difficult to understand the true relationship between dietary soy intake and breast cancer risk (if one exists). There is, for example, both laboratory and clinical data suggesting that a diet rich in soybean-derived products may be associated with a lower risk of developing breast cancer. At the same time, because genistein and other dietary isoflavones are known to weakly mimic the effects of estrogen, there has been some concern that a diet rich in isoflavone “phytoestrogens” may increase both the risk of developing a new breast cancer and the risk of developing a recurrence of a previous breast cancer. (In fact, there is data from laboratory research studies showing that genistein can indeed fuel the growth of human breast cancer cells growing in culture dishes, when exposed to high concentrations of this soy-derived isoflavone.)

A growing body of public health research, primarily from Asian countries where tofu and other soy-based foods are frequently consumed, appears to link increased soy consumption with a decreased lifetime breast cancer risk, particularly when soy-based foods are consumed during adolescence, during the time when development of the female breast is most active (Soy & Breast Cancer Risk). (Interestingly, there is also recent research suggesting that soy products might also reduce the risk of prostate cancer, which is another hormonally driven cancer: Genistein & Prostate Cancer Cells, Dietary Soy & Prostate Cancer Risk.)

Although epidemiological research is, increasingly, suggesting that a diet rich in soybean-derived foods might lower a woman’s lifetime risk of developing breast cancer, many breast cancer experts have remained apprehensive regarding dietary isoflavone intake in women with a prior history of breast cancer, in view of the estrogen-like effects of these “phytoestrogens.” As I have already noted, there is considerable research data available to suggest that soy-derived isoflavones can, at least under certain laboratory conditions, stimulate estrogen-sensitive breast cancer cells to grow and divide. These research findings have left many oncologists feeling uncomfortable in recommending soy-based foods to their breast cancer patients. Now, a newly publish public health study in the Journal of the American Medical Association suggests that soy-based foods may actually reduce the risk of breast cancer recurrence, and death due to any cause, in women who have previously been diagnosed with this very common form of cancer.

In this study, which was performed in Shanghai, China, 5,042 female breast cancer survivors (ages 20 to 75 years) were followed for an average of almost 4 years. All of these patient volunteers underwent detailed surveys regarding their lifestyle habits, including their diets. These patients, who were originally diagnosed with breast cancer between 2002 and 2006, were surveyed at 6, 18, 36 and 60 months following their original diagnosis with breast cancer.

The results of this study indicate that the breast cancer survivors who consumed the greatest amount of soy-based foods in their daily diets were 32 percent less likely to experience a recurrence of their breast cancer when compared to the women who consumed the least amount of soy-based isoflavones. Moreover, the women who consumed the greatest amount of soy were also 29 percent less likely to die, from any cause, when compared to the women who consumed the least amount of soy-derived foods.

A particularly interesting and unexpected finding of this study was that both women with estrogen sensitive breast cancers and women with tumors that were not sensitive to estrogen appeared to experience a significantly decreased risk of breast cancer recurrence if they frequently consumed soy products. Another important finding of this study was that women who were taking the estrogen-blocking cancer treatment drug tamoxifen also appeared to enjoy a reduced risk of breast cancer recurrence with higher levels of dietary soy intake. Additionally, the researchers noted that high levels of soy intake appeared to be about as effective in reducing the risk of breast cancer recurrence as the breast cancer prevention drug tamoxifen, alone.

The results of this very important study mirror the findings of the only other prospective clinical study that has looked at the impact of soy-based foods on breast cancer recurrence (the “Life After Cancer Epidemiology,” or “LACE,” study). The LACE study, which was performed in the United States, followed nearly 2,000 breast cancer survivors for, on average, more than 6 years. In the LACE study, women who were taking tamoxifen, and who also consumed the highest amount of soy-based dietary isoflavones, were 50 percent less likely to develop a recurrence of their breast cancer when compared to women who reported the lowest consumption of soy-derived foods.

As I have pointed out previously, epidemiological research studies based upon dietary surveys are susceptible to several types of bias which, in turn, can cause researchers to draw the wrong conclusions. In this case, however, there are now two large prospective cohort studies that have reached essentially the same conclusions (albeit with a rather limited duration of patient follow-up). Both studies strongly suggest that high levels of soy-based isoflavones in the diet may be able to significantly reduce the risk of breast cancer recurrence. Based upon the findings of this large Chinese study, the apparent cancer risk reduction effect associated with high levels of soy intake also appears to benefit premenopausal and postmenopausal women, as well as women who are taking the estrogen-blocking drug tamoxifen, women with estrogen-sensitive tumors, and women with (counter-intuitively) estrogen-resistant tumors.

In view of the limited duration of patient follow-up in both of these clinical breast cancer studies, as well as the limitations of survey-based epidemiological research in general, I would like to see updated data from both of these studies after at least 10 years of patient observation before I would be willing to tell my breast cancer patients that they should significantly increase their dietary soy intake. On the other hand, the rather compelling data presented by both of these clinical research studies will also make me less anxious when any of my breast cancer patients decide, of their own accord, to increase their intake of soy-derived isoflavones.

Disclaimer: As always, my advice to readers is to seek the advice of your physician before making any significant changes in medications, diet, or level of physical activity

Dr. Wascher is an oncologic surgeon, a professor of surgery, a cancer researcher, an oncology consultant, and a widely published author