Category Archives: Cancer

Paleo Diet Linked to Lower Risk of Colorectal Cancer

He has no interest in colon cancer prevention

Excluding skin cancers, colorectal cancer is the 3rd most common cancer diagnosed in Los Estados Unidos. I bet it’s the same in Europe. Overall, the lifetime risk of developing colorectal cancer is about 1 in 23 (4.3%) for men and 1 in 25 (4.0%) for women. Physicians believe that colon cancer originates in colon polyps (usually adenomas), which is why your gastroenterologist removes polyps when he finds them during colonoscopy.

From the American Cancer Society:

Most colorectal cancers start as a growth on the inner lining of the colon or rectum. These growths are called polyps.

Some types of polyps can change into cancer over time (usually many years), but not all polyps become cancer. The chance of a polyp turning into cancer depends on the type of polyp it is. There are different types of polyps.

  • Adenomatous polyps (adenomas): These polyps sometimes change into cancer. Because of this, adenomas are called a pre-cancerous condition. The 3 types of adenomas are tubular, villous, and tubulovillous. 
  • Hyperplastic polyps and inflammatory polyps: These polyps are more common, but in general they are not pre-cancerous. Some people with large (more than 1cm) hyperplastic polyps might need colorectal cancer screening with colonoscopy more often. 
  • Sessile serrated polyps (SSP) and traditional serrated adenomas (TSA): These polyps are often treated like adenomas because they have a higher risk of colorectal cancer.

A recent study suggests that the paleo diet may lower risk of colorectal cancer. I haven’t read the full study report. Are we changing the “paleo diet” to “evolutionary-concordance diet and lifestyle pattern”? ECDLP? I don’t think so.

Abstract

Differences in diet and lifestyle relative to those of our Paleolithic-era ancestors may explain current high incidences of chronic diseases, including colorectal cancer (CRC), in Westernized countries. Previously reported evolutionary-concordance diet and lifestyle pattern scores, reflecting closeness of diet and lifestyle patterns to those of Paleolithic-era humans, were associated with lower CRC incidence. Separate and joint associations of the scores with colorectal adenoma among men and women are unknown. To address this, we pooled data from three case-control studies of incident, sporadic colorectal adenomas (n = 771 cases, 1,990 controls), used participants’ responses to food frequency and lifestyle questionnaires to calculate evolutionary-concordance diet and lifestyle pattern scores, and estimated the scores’ associations with adenomas using multivariable unconditional logistic regression. The multivariable-adjusted odds ratios comparing those in the highest relative to the lowest diet and lifestyle score quintiles were 0.84 (95% confidence interval [CI] 0.62, 1.12; Ptrend:0.03) and 0.41 (95% CI 0.29, 0.59; Ptrend:<0.0001), respectively. The inverse associations were stronger for high-risk adenomas, and among those with both high relative to those with both low diet and lifestyle scores. These results suggest that more evolutionary-concordant diet and lifestyle patterns, separately and jointly, may be associated with lower risk for incident, sporadic colorectal adenoma.


Steve Parker, M.D.

Reference at Nutrition and Cancer: Associations of Evolutionary-Concordance Diet and Lifestyle Pattern Scores with Incident, Sporadic Colorectal Adenoma in a Pooled Case-Control Study

PS: Another diet linked to lower risk of colon cancer is the Mediterranean diet.

Is “evolutionary-concordance lifestyle” the new “paleo diet”?

From the March 6, 2021, European Journal of Nutrition:

Sedentary lifestyle NOT an option back then

Purpose:

Evolutionary discordance may contribute to the high burden of chronic disease-related mortality in modern industrialized nations. We aimed to investigate the associations of a 7-component, equal-weight, evolutionary-concordance lifestyle (ECL) score with all-cause and cause-specific mortality.

Methods:

Baseline data were collected in 2003-2007 from 17,465 United States participants in the prospective Reasons for Geographic and Racial Differences in Stroke (REGARDS) study. The ECL score’s components were: a previously reported evolutionary-concordance diet score, alcohol intake, physical activity, sedentary behavior, waist circumference, smoking history, and social network size. Diet was assessed using a Block 98 food frequency questionnaire and anthropometrics by trained personnel; other information was self-reported. Higher scores indicated higher evolutionary concordance. We used multivariable Cox proportional hazards regression models to estimate ECL score-mortality associations.

Results:

Over a median follow-up of 10.3 years, 3771 deaths occurred (1177 from cardiovascular disease [CVD], 1002 from cancer). The multivariable-adjusted hazard ratios (HR) (95% confidence intervals [CI]) for those in the highest relative to the lowest ECL score quintiles for all-cause, all-CVD, and all-cancer mortality were, respectively, 0.45 (0.40, 0.50), 0.47 (0.39, 0.58), and 0.42 (0.34, 0.52) (all P trend < 0.01). Removing smoking and diet from the ECL score attenuated the estimated ECL score-all-cause mortality association the most, yielding fifth quintile HRs (95% CIs) of 0.56 (0.50, 0.62) and 0.50 (0.46, 0.55), respectively.

Conclusions:

Our findings suggest that a more evolutionary-concordant lifestyle may be inversely associated with all-cause, all-CVD, and all-cancer mortality. Smoking and diet appeared to have the greatest impact on the ECL-mortality associations.

Source: A novel evolutionary-concordance lifestyle score is inversely associated with all-cause, all-cancer, and all-cardiovascular disease mortality risk – PubMed

Steve Parker, M.D.

Could a paleolithic lifestyle intervention help breast cancer patients undergoing radiotherapy?

A modern paleo meal

We don’t know from the study at hand.

This pilot and feasibility study involved only 11 patients that completed the study. The main finding was a loss of about a pound of fat weight weekly. Hey abstract writer, how about telling us how long the study lasted? Anyway, breast cancer patients primarily want to know what a particular management approach will do for their cure rate and quality of life.

Abstract

Evolutionary principles are rarely considered in clinical oncology. We here aimed to test the feasibility and effects of a dietary and physical activity intervention based on evolutionary considerations in an oncological setting. A total of 13 breast cancer patients referred to our clinic for curative radiotherapy were recruited for this pilot study. The women were supposed to undertake a “Paleolithic lifestyle” (PL) intervention consisting of a Paleolithic diet and daily outdoor activity of at least 30 min duration while undergoing radiotherapy. Body composition was measured weekly by bioimpedance analysis. Blood parameters were assessed before, during, and at the end of radiotherapy. A control group on an unspecified standard diet (SD) was assigned by propensity score matching. A total of eleven patients completed the study. The majority of patients (64%) reported feeling good or very good during the intervention. The intervention group experienced an average decrease of 0.4 kg body weight (p < 0.001) and 0.34 kg (p < 0.001) fat mass per week, but fat-free and skeletal muscle mass were not significantly affected. Vitamin D levels increased slightly from 23.8 (11-37.3) ng/ml to 25.1 (22.6-41.6) ng/ml (p = 0.053). β-hydroxybutyrate levels were significantly increased and triglycerides and free T3 hormone levels significantly reduced by the PL intervention. This pilot study shows that adoption of a PL intervention during curative radiotherapy of breast cancer patients is feasible and able to reduce fat mass. Daily outdoor activity could eliminate vitamin D deficiency (vitamin D < 20 ng/ml). Future studies are needed to confirm these findings.

Source: Short-term effects of a Paleolithic lifestyle intervention in breast cancer patients undergoing radiotherapy: a pilot and feasibility study – PubMed

We don’t know if the paleo diet prevents breast cancer. But I know one diet that does: the traditional Mediterranean diet.

Steve Parker, M.D.

Reduce Your Risk of Cancer By Up to 25%

hypoglycemia, woman, rock-climbing

This activity could increase your odds of accidental death by up to 100%

What I dislike about a phrase like “…up to 25%” is that it includes only 1%.

From UPI:

In findings published Thursday in the Journal of Clinical Oncology, researchers at the National Cancer Institute, the American Cancer Society, and the Harvard T.H. Chan School of Public Health report that people who engaged in physical activity as recommended by the National Institutes of Health were able to reduce their risk for seven different types of cancer by as much as 25 percent.

This included common—and deadly—forms of the disease like colon and breast cancers, as well as endometrial cancer, kidney cancer, myeloma, liver cancer, and non-Hodgkin lymphoma.

*  *  *

Updated federal guidelines for physical activity recommend that people should aim for two and a half to five hours per week of moderate-intensity activity or 75 to 150 minutes per week of “vigorous activity.”

Source: Exercise may reduce risk for cancer by as much as 25 percent – UPI.com

Steve Parker, M.D.

Click pic to purchase book at Amazon.com. E-book versions available at Smashwords.com.

Red Meat Not Quite as Deadly as Imagined

From New York Times:

Public health officials for years have urged Americans to limit consumption of red meat and processed meats because of concerns that these foods are linked to heart disease, cancer and other ills.

But on Monday, in a remarkable turnabout, an international collaboration of researchers produced a series of analyses concluding that the advice, a bedrock of almost all dietary guidelines, is not backed by good scientific evidence.

Whew…What a relief! Dodged that bullet.

Click for Gina Kolata’s article.

Steve Parker, M.D.

Click pic to purchase book at Amazon.com. E-book versions available at Smashwords.com.

Reduce Your Cancer Risk Via Diet and Exercise

You need to worry about cancer because you have a roughly four in 10 chance of coming down with invasive cancer. (Skin cancers like squamous cell and basal cell are quite common, but rarely invasive.)

Dr. David Gorski is a breast cancer surgeon. He’s looked at the scientific literature on the linkage between diet and exercises, and the risk of developing cancer.

Here’s his conclusion from his review at Science-Based Medicine:

“You can reduce your risk of cancer by staying active and exercising, eating a healthy diet with a lot of plant-based foods and minimizing intake of processed meats, limiting alcohol consumption (although I think the WCRF/AICR guidelines go a bit too far in saying that you shouldn’t drink at all if possible), and maintaining a healthy weight. (Of course, if you stay active and eat a healthy diet, maintaining a healthy weight will probably not be a problem.) Conceptually, it’s easy to do. In practice, as I’m discovering, it’s anything but easy.”

Source: Diet and exercise versus cancer: A science-based view « Science-Based Medicine

The Mediterranean diet seems to protect against cancer.

Steve Parker, M.D.

PS: One of the reasons I write diet books is that I want to keep you from getting cancer.

Exercise Cancels the Cancer-Inducing Effect of Alcohol

Jamesons Irish Whiskey Photo copyright: Steve Parker MD

Jameson Irish Whiskey
Photo copyright: Steve Parker MD

Just recently we learned that you’ll die of cancer if you tipple. Well, a new study says you can counteract the carcinogenic alcohol with adequate physical activity.

A story at CNN tells us how much exercise it takes :

“Specifically, they looked at the impact of the recommended amount of weekly exercise for adults, which is 150 minutes of moderate aerobic activity. That includes brisk walking, swimming and mowing the lawn, according to the US Department of Health and Human Services. HHS also advises strength training for all major muscle groups at least twice a week.”

Source: Exercise can cancel out the booze, says study – CNN.com

The rule of thumb on how much alcohol is relatively safe to drink is 7 typical drinks a week for women, and 14 for men. Don’t drink them all at once.

Also remember that even one or two drinks under the right circumstances can have devastating consequences.

Steve Parker, M.D.

PS: All of my books have extensive recommendations on getting started with exercise, even if you’re a 300-lb couch potato.

It’s the Carbs, Not Saturated Fat: Food consumption and the rate of cardiovascular diseases in 42 European countries 

 

Carcinogenic?

Carcinogenic?

The idea that heart attacks and other cardiovascular diseases are caused by dietary saturated fats is losing credibility. I lost faith in that theory in 2009.

Instead, cardiovascular disease is now linked to high consumption of carbohydrates, particularly those carbs that are rapidly absorbed and turned into blood sugar.

Unfortunately, the diet that reduces risk of cardiovascular disease may increase your risk of cancer. Keep reading.

If you’re a nutrition science nerd, here’s a pertinent report from researchers at Masaryk University in the Czech Republic:

“The results of our study show that high-glycaemic carbohydrates or a high overall proportion of carbohydrates in the diet are the key ecological correlates of cardiovascular disease (CVD) risk. These findings strikingly contradict the traditional ‘saturated fat hypothesis’, but in reality, they are compatible with the evidence accumulated from observational studies that points to both high glycaemic index and high glycaemic load (the amount of consumed carbohydrates × their glycaemic index) as important triggers of CVDs. The highest glycaemic indices (GI) out of all basic food sources can be found in potatoes and cereal products, which also have one of the highest food insulin indices (FII) that betray their ability to increase insulin levels.The role of the high glycaemic index/load can be explained by the hypothesis linking CVD risk to inflammation resulting from the excessive spikes of blood glucose (‘post-prandial hyperglycaemia’). Furthermore, multiple clinical trials have demonstrated that when compared with low-carbohydrate diets, a low-fat diet increases plasma triglyceride levels and decreases total cholesterol and HDL-cholesterol, which generally indicates a higher CVD risk. Simultaneously, LDL-cholesterol decreases as well and the number of dense, small LDL particles increases at the expense of less dense, large LDL particles, which also indicates increased CVD risk. These findings are mirrored even in the present study because cereals and carbohydrates in general emerge as the strongest correlates of low cholesterol levels.

In light of these findings, the negative correlation of refined sugar with CVD risk may seem surprising, but the mean daily consumption of refined sugar in Europe is quite low (~84 g/day), when compared with potato and cereal carbohydrates (~235 g/day), and makes up only ~20% of CA energy. Refined sugar is also positively tied to many animal products such as animal fat and total fat and animal protein, and negatively to % PC CARB energy and % CA energy. Therefore, a high consumption of refined sugar is accompanied by a high consumption of animal products and lower intakes of other carbohydrates. Furthermore, the glycaemic index of refined sugar (sucrose) is rather moderate (~65).”

Source: Food consumption and the actual statistics of cardiovascular diseases: an epidemiological comparison of 42 European countries | Grasgruber | Food & Nutrition Research

Elsewhere in this long article:

“Current rates of cancer incidence in Europe are namely the exact geographical opposite of CVDs. In sharp contrast to CVDs, cancer correlates with the consumption of animal food (particularly animal fat), alcohol, a high dietary protein quality, high cholesterol levels, high health expenditure, and above average height. These contrasting patterns mirror physiological mechanisms underlying physical growth and the development of cancer and CVDs. The best example of this health paradox is again that of French men, who have the lowest rates of CVD mortality in Europe, but the highest rates of cancer incidence. In other words, cancer and CVDs appear to express two extremes of a fundamental metabolic disbalance that is related to factors such as cholesterol and IGF-1 (insulin-like growth factor).”

I wish these researchers had looked at over death rates associated with various ways of eating. Perhaps that will be in a future paper.

I’d rather die of a heart attack than cancer.

Steve Parker, M.D.

Don’t Do It: Exercise Promotes Cancer

Needs a bit more hormetic stress

“Would you spot me, bro?”

I’ve always assumed that exercise reduces the risk of cancer, contributing to the well-established fact that folks who exercise live longer than others.

But a recent study found a positive association between exercise and two cancers: melanoma and prostate.

The good news is that exercise was linked to lower risk of 13 other cancers.

Here’s a quote for the New York Times Well blog:

The researchers found a reduced risk of breast, lung and colon cancers, which had been reported in earlier research. But they also found a lower risk of tumors in the liver, esophagus, kidney, stomach, endometrium, blood, bone marrow, head and neck, rectum and bladder.

And the reductions in risk for any of these 13 cancers rose steeply as people exercised more. When the researchers compared the top 10 percent of exercisers, meaning those who spent the most time each week engaging in moderate or vigorous workouts, to the 10 percent who were the least active, the exercisers were as much as 20 percent less likely to develop most of the cancers in the study.

I’m surprised the protective effect of exercise against cancer wasn’t stronger.

Action Plan

So how much physical activity does it take to prevent cancer? And what type of exercise? We await further studies for specific answers.

I’m hedging my bets with a combination of aerobic and strength training two or three times a week.

Steve Parker, M.D.

PS: If you think cancer’s bad, read one of my books. Wait, that didn’t come out right.

PPS: Men with diabetes seem to be less likely than average to get prostate cancer.

Paleolithic and Mediterranean Diets Linked to Lower Incidence of Colon Polyps

Adenomas in the colon (aka colon polyps) are precursors to colon cancer. Experts think that if we can prevent the onset of colon polyps, we’ll see less colon cancer. A recent study suggests that both a Paleo-type diet and Mediterranean-style diet reduce risk of colon polyps. A sample:

“Colorectal cancer (CRC) is the third most commonly diagnosed cancer and the second-leading cause of cancer mortality in the United States. Rapidly increasing incidence rates in previously low-incidence populations in urban China and Japan and among male Polynesians in Hawaii have coincided with the adoption of a more westernized lifestyle by those populations. These changing incidence rates, along with studies of immigrant populations, point to a strong influence of diet and other lifestyle factors on CRC risk.”

Source: Paleolithic and Mediterranean Diet Pattern Scores and Risk of Incident, Sporadic Colorectal Adenomas