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Category: cancer

Published on Leave a comment on Regular Exercise Has Anticancer Effects

Evidence is accumulating that engaging in exercise may not only prevent cancer, but that in those who already have cancer - it may prevent progression of the cancer. Fantastic!

A large 2019 review of 9 studies (755,459 individuals) found that 2 1/2 hours per week of "moderate-intensity" physical activity or exercise (e.g. brisk walks) really lowers the risk of 7 cancers: colon, breast, endometrial, kidney, myeloma, liver, and non-Hodgkin lymphoma. Some (but not all) were lowered in a dose response manner, that is, the more exercise (up to 5 hours per week), the bigger the protective effect.

Another 2019 review article stated that there are hundreds of studies in the field of "exercise oncology" which have examined the effect of exercise on cancer in humans. The studies find that exercise may prevent cancer, control cancer progression, and interact positively with anticancer therapies. (One example: a study found regular moderate or vigorous physical activity is associated with lower rates of death in men diagnosed with prostate cancer.)

In addition, hundreds of animal (mice and rat) and laboratory studies show that the anticancer effects of exercise are causal, not just an association. There is evidence that each exercise session actually has an effect on cancer tumors. And that the more exercise sessions, the bigger the effect!

Bottom line: Get out and move, move, move! Plan to do this every week for years.

An infographic that illustrates how exercise has anticancer effects, from The Scientist:  Infographic: Exercise’s Anticancer Mechanisms

Excerpts from the accompanying April 2020 article by Prof. Bente K. Pedersen (Univ. of Copenhagen) on how regular exercise has anticancer effects. From The Scientist: Regular Exercise Helps Patients Combat Cancer

Physical exercise is increasingly being integrated into the care of cancer patients such as Mathilde, and for good reason. Evidence is accumulating that exercise improves the well being of these patients by combating the physical and mental deterioration that often occur during anticancer treatments. Most remarkably, we are beginning to understand that exercise can directly or indirectly fight the cancer itself.  ...continue reading "Regular Exercise Has Anticancer Effects"

Published on Leave a comment on Breastfeeding Associated With A Lower Risk Of Ovarian Cancer

Some more good news for women who breastfeed their babies. A large international study found an association between breastfeeding and an average 24% lower incidence of ovarian cancer years later (when compared to women who never breastfed).

But if you look at the results more closely, you see that the longer the woman breastfeeds, the lower the risk of ovarian cancer - so that breastfeeding for 3 months was associated with an 18% lower risk, while breastfeeding for 12 months or more is associated with a 34% lower risk.

Over the years, other studies found that breastfeeding is associated with a number of health benefits for the mother, such as a lower risk of diabetes and breast cancer.

From Medical Xpress: Breastfeeding linked to lower ovarian cancer risk ...continue reading "Breastfeeding Associated With A Lower Risk Of Ovarian Cancer"

Published on Leave a comment on Bariatric Surgery, Weight loss, and Lower Risk of Skin Cancer

Another great reason to lose weight if you are really overweight (let's be honest, the term is "obese") is a lower risk of two types of skin cancer: squamous cell carcinoma and melanoma. Obesity is considered a cancer risk, that is, it increases the risk of cancer, and after bariatric surgery there is a lower risk of cancer.

A long-running study in Sweden (Swedish Obese Subjects study) followed 2 groups of obese individuals for 18 years - 1 group received bariatric surgery (2007 persons) and the other group didn't (2040 persons). They found that the group who had received bariatric surgery, along with a large weight loss, had a significantly lower risk of getting squamous cell carcinoma and melanoma  than the group who received conventional "obesity treatment" (such as advice on losing weight).

How much weight did they lose after the surgery? After 2 years the average weight loss in the surgery group was 63.27 pounds (28.7 kg), which leveled off to 47.62 lbs (47.62 kg) by the 15 year follow-up visit. The weight changes in the non-surgery (control) group was small and never exceeded 6.61 pounds in gains or losses.

The researchers give a number of reasons why a large weight loss may be contributing to reduced risk of skin cancer, including leptin uptake changes, lower chronic systemic inflammation, and changes in gut microbes. In summary, they found a 42% lower risk for both forms of skin cancer combined, and 57% lower risk of malignant melanoma in the surgery group (as compared to the non-surgery group).

BOTTOM LINE: If you are really overweight, then try, try, try to lose a big chunk of weight. Your body will thank you in many ways. Not just lower risk of some cancers (including breast cancer), lower risk of diabetes, increased chance of diabetes reversal, lower risk of dementia, lower chronic systemic inflammation, better sperm quality, and on and on.

The CDC says that a person with a BMI (Body Mass Index) of 30.0 or higher is obese, and being overweight is a BMI of 25 to less than 30. [Body Mass Index table]

From Medical Xpress: Lower risk for malignant melanoma after bariatric surgery   ...continue reading "Bariatric Surgery, Weight loss, and Lower Risk of Skin Cancer"

Published on Leave a comment on Exercise May Lower The Risk Of Some Cancers

Exercise appears to protect against some cancers. Yes, something so simple as merely getting the recommended amount of 2 1/2 hours per week of exercise (e.g. brisk walks) really lowers the risk of 7 cancers: colon, breast, endometrial, kidney, myeloma, liver, and non-Hodgkin lymphoma.

The researchers analyzed 9 studies for a total of 755,459 individuals (median age 62 years, 53% females) who were followed for 10.1 years, and found that 50,620 cancers developed. They specifically looked at 15 cancers and found that exercise lowered the risk of 7 cancers. Some, but not all, were lowered in a dose response manner, that is, the more exercise, the bigger the protective effect (e.g. breast, colon, endometrial cancer). How much the cancer risk was lowered with exercise varied by types of cancer: colon (8%-14% lower risk in men), breast (6%-10% lower risk), endometrial (10%-18% lower risk), kidney (11%-17% lower risk), myeloma (14%-19% lower risk), liver (18%-27% lower risk), and non-Hodgkin lymphoma (11%-18% lower risk in women).

How much exercise was needed for a cancer protective effect? About 2 1/2 to 5 hours per week of moderate-intensity physical activity, such as brisk walking. The study looked at "leisure-time" exercise, which can include exercise, sports or any recreational activity which is typically "moderate to vigorous intensity".

The Physical Activity Guidelines from the US Department of Health and Human Services recommends that adults do at least 150 to 300 minutes of moderate-intensity physical activity a week, or 75 to 150 minutes of vigorous-intensity activity, or an equivalent combination of moderate- and vigorous-intensity activity. Brisk walking is moderate intensity physical activity. Bottom line: get out and move, move, move!

From Medical Xpress: Report links recommended physical activity levels to lower risk of seven cancers   ...continue reading "Exercise May Lower The Risk Of Some Cancers"

Published on Leave a comment on High Fiber Foods, Yogurt, and Lung Cancer

Food is all important for health. A recent study (that analyzed data from 10 large studies in the US, Europe, and Asia) found an association between high fiber intake from foods and also frequent eating of yogurt with a lower incidence of lung cancer. Persons with the highest yogurt and fiber consumption had a 33% reduced risk of lung cancer (when compared to the group who did not consume yogurt and consumed the least amount of fiber).

Think of it this way: The fiber in foods feeds the beneficial bacteria in the gut. High fiber foods that feed microbes in the gut are known as prebiotics. It is good to eat a variety of foods, because they provide a variety of fibers. High fiber foods are whole grains, fruits, vegetables, seed, nuts, and legumes (beans).

Gut microbes use fiber to generate short-chain fatty acids, and these are anti-inflammatory. Evidence suggests that the beneficial effects are not restricted to the gut, but reach organs throughout the body, including the lungs. The researchers suggest that both fiber and yogurt have anti-inflammatory effects, and the combination of fiber and yogurt is stronger against lung cancer than either alone. They also thought that the Lactobacillus and Bifidobacterium species in yogurt somehow help improve the gut microbial system.

From Medical Xpress:  High fiber, yogurt diet associated with lower lung cancer risk  ...continue reading "High Fiber Foods, Yogurt, and Lung Cancer"

Published on Leave a comment on Onions, Garlic, and Lower Risk of Breast Cancer

Good news for women who really like to eat onions and garlic! A study conducted in Puerto Rico found that women who more frequently consumed garlic and onions, especially  "sofrito", had a lower risk of breast cancer. Both onions and garlic are an important part of the Puerto Rican diet, and sofrito is a raw onion and garlic based condiment or puree that is the base for many Puerto Rican dishes.

This study found that as consumption of garlic and onions increased, there was a decrease in the risk of breast cancer, which was true for women both before menopause or after menopause. There was evidence of a dose-response (the more eaten, the lower the risk). This association was especially strong for women consuming sofrito more than once a day - they had a 67% decrease in breast cancer risk compared to those who never ate sofrito.

The researchers point out that studies show that the more one eats of onions and garlic, the lower the risk of certain cancers, such as the lung, prostate, colon, and stomach. However, the evidence for whether it has a protective effect on breast cancer has been mixed, but with most studies finding a protective effect with frequent consumption of onions and garlic, especially raw onions and garlic. One study in Mexico found a 70% lower risk of breast cancer in those eating one slice of onion per day, compared to those eating less than one slice. The researchers also mentioned that studies find that cooking onions and garlic reduces their anticancer activity.

From Science Daily: Onion and garlic consumption may reduce breast cancer risk

Onions and garlic are key ingredients in sofrito, a condiment that's a staple of Puerto Rican cuisine. They may also be a recipe for reducing the risk of breast cancer. ...continue reading "Onions, Garlic, and Lower Risk of Breast Cancer"

Published on Leave a comment on Eating Foods Rich In Flavonoids Has Health Benefits

A new large study found that eating a flavonoid rich diet is associated with a lower risk of death. Flavonoids are compounds found in abundance in plant derived foods and beverages, such as fruits, vegetables, dark chocolate, tea, legumes, and red wine. The study followed about 56,000 people in Denmark for 23 years and found that eating higher levels of flavonoid rich foods was associated with a lower risk of death from any cause (all-cause mortality), heart disease (cardiovascular disease), and cancer.

The researchers found that there was an inverse relationship (the more one eats, the lower the risk of death), and that this relationship was strongest among cigarette smokers and people who consume high amounts of alcohol (more than 20 grams per day). Bottom line: Make sure your diet includes lots of fruits, vegetables, legumes, and dark chocolate (yes!).

By the way, while other studies do find a lower incidence of heart disease and cancer in people eating a diet rich in flavonoids, in this study they were not looking at who got the diseases, but looked at deaths. Therefore the following title is misleading. It should instead say "... protects against cancer and heart disease deaths..." From Science Daily: Flavonoid-rich diet protects against cancer and heart disease, study finds  ...continue reading "Eating Foods Rich In Flavonoids Has Health Benefits"

Published on Leave a comment on Are We Looking At Sunlight and Health the Wrong Way?

Are we looking at vitamin D and sunlight the wrong way? Back in 2016 I posted about the results of a long-running Swedish study that made me rethink everything I knew about sunlight and health. (The prevailing view of dermatologists at the time and now is: to always use sunscreen if going outdoors in order to lower the risk of skin cancer. In other words, that sunlight is always harmful.)

The Swedish study followed women for 20 years and found that: Women who had more sunlight exposure experienced a lower mortality rate than women who avoided sun exposure. However, they were at an increased risk of skin cancer. But those with more sun exposure lived longer due to a decrease in heart (cardiovascular) disease and other noncancer reasons. And the most surprising finding: Nonsmokers who avoided sun exposure had a similar life expectancy as smokers with the highest sun exposure. In other words: avoidance of sun exposure = cigarette smoking when looking at life expectancy. And the results of sun exposure was dose-dependent, with the more, the better for longer life expectancy.

The researchers suggested that  a person's vitamin D levels might be just a marker of sun exposure, which other studies and articles now also suggest. So while we measure vitamin D levels in studies, maybe we should instead be looking at sunlight exposure.

Since then I read more studies that found other benefits of sunlight exposure, such as sunlight having low levels of "blue light" which energizes T cells. T cells are a type of white blood cell, are part of the immune system, and help protect the body from infection and cellular abnormalities (cancer). An earlier study found that exposing skin to sunlight may help to reduce blood pressure and thus cut the risk of heart attack and stroke.

This year I read the following two nicely written articles about this whole issue, both a little different - so worth reading both to get a good idea about the research and the debate.

1) From Outside: Is Sunscreen the New Margarine?

2) From Elemental Medium: What If Avoiding the Sun Is Bad for You?

And once again, a link to the 20 year Swedish study, from the Journal of Internal Medicine: Avoidance of sun exposure as a risk factor for major causes of death: a competing risk analysis of the Melanoma in Southern Sweden cohort

Published on Leave a comment on Vitamin A and Skin Cancer Risk

A recent large study found that getting high levels of vitamin D from foods, but not supplements, is linked to a lower rate of a common skin cancer (squamous cell carcinoma) years later. Once again: the beneficial health effect is associated with eating real foods, but not supplements.

Researchers found an inverse relationship with vitamin A intake and squamous cell carcinoma - those that had the highest dietary intake of vitamin A had a 17 % reduction of the skin cancer during the next 26 years. The inverse associations were highest among those with moles and those who had sunburns during childhood or adolescence.

The high intake group had the vitamin A amount equivalent to one medium baked sweet potato or 2 large carrots each day. Most of their intake came from fruitsand vegetables. Vitamin A (retinoids) is important in keeping skin cells healthy, and retinoids are considered cancer protective (or anticancer) for several cancers.

What foods are high in vitamin A?  Plant-based sources of vitamin A (carotenoids, including lutein and lycopene) include orange and yellow fruits  and vegetables, such as sweet potatoes, carrots, butternut squash, pumpkin, apricots, cantaloupe, red peppers, tomatoes, as well as broccoli, spinach, and leafy dark vegetables. Animal based sources of vitamin A  (retinol) are dairy foods (milk, cheese, yogurt), eggs, some types of fish (e.g. herring), and beef liver. (More information at National Institutes of Health.)

From Futurity: CAN GETTING MORE VITAMIN A CUT SKIN CANCER RISK?  ...continue reading "Vitamin A and Skin Cancer Risk"

Published on Leave a comment on Vitamin D and Cancer

For years researchers have been finding links between vitamin D and all sorts of health benefits, including lower incidence of cancer with higher vitamin D levels. A recent study by Michigan State physicians found that taking vitamin D supplements for at least 3 years resulted in cancer patients living longer, that is, "having significant reduction of cancer-related mortality" . However, it did not prevent cancer.

One issue with much of the vitamin D research that has been done is whether vitamin D is really  causing these health benefits or is it just an association? Perhaps people who take vitamin D are also different in some way from those who  don't, or something else is going on, and this may be confusing the results.What was nice about this  study is that it was a review of studies already done, but the researchers only included vitamin D studies  that used randomly controlled trials (RCT).

In the RCTs  included in the study, people were randomly assigned to different groups and either they were 1) given vitamin D supplements for 3 years or more, or 2) they did not take vitamin D supplements (the placebo group). Thus they evaluated 10 RCT studies with 79,055 persons who were followed for 4 years or more. Vitamin D was associated with significant reduction of cancer-related deaths (when compared with the placebo group). But there was no reduction in cancer incidence. Meaning the vitamin D did not prevent cancer (have a protective effect) in the studies they looked at.

The researchers did not say what they thought was an optimal vitamin D supplement dose or optimal levels in the blood. By the way, keep in mind that vitamin D can easily be gotten from exposure to sunshine. After all, it is called the sunshine vitamin.

From Science Daily: Vitamin D could help cancer patients live longer   ...continue reading "Vitamin D and Cancer"