How to reduce the risk of prostate cancer

A way to reduce the risk of prostate cancer

According to a study by scientists from the University of Southern California and the California Institute for Cancer Prevention, eating pan-fried red meat increases the risk of developing prostate cancer by 40%.

Mariana Stern and colleagues at the Keck School of Medicine at the University of Southern California studied the effect of red meat and poultry consumption, as well as the types of preparation and hereditary predisposition, on the risk of Prostate cancer. The information that there is a link between the frequent consumption of red meat and cancer has long been known, but the evidence base for different types of tumors is still insufficient. The dependence of the risk of developing prostate cancer on the method of cooking meat indicates that the leading role in the occurrence of a tumor belongs to carcinogens that are produced in meat under the influence of high temperature.

The authors of the study studied information about 2953 male participants in the study on a case-control basis, of which 717 people were diagnosed with localized forms of prostate cancer, and 1140 with advanced prostate cancer, 1096 did not have prostate cancer and made up the control group.

All participants filled out a special questionnaire, which made it possible to find out what kind of meat, in what dishes and in what quantity was included in the diet of the male participants in the study. For each type of meat preparation (grilling, baking, frying), special photos were offered, with the help of which it was determined how strongly the meat was thermally processed.

"We found that men who ate more than 1.5 servings of pan-fried meat per week had a 30% higher risk of developing advanced prostate cancer," Dr. Stern said. .5 servings of red meat that was cooked at a high temperature increased the risk by 40%." A serving of meat was considered an amount approximately equal to 90 g.

During a detailed analysis, it was found that, for example, eating hamburgers, unlike steaks, had a very strong effect on the risk of developing prostate cancer

At the same time, men who preferred roasted poultry had a lower risk of developing prostate cancer, while eating pan-fried poultry was significantly associated with an increased risk of prostate cancer. Thus, the authors concluded that frying meat in a pan, regardless of its type, in any case leads to an increased risk of developing prostate cancer. Similar results were obtained by scientists in relation to fish in their previous study.

According to the authors, the leading role in the process of tumor formation belongs to carcinogens heterocyclic amines, which can have a harmful effect on DNA. These substances are synthesized by the interaction of sugar and amino acids at high temperatures for a long time during cooking. Other carcinogens are polycyclic aromatic carbohydrates formed when meat is smoked or grilled, when the fat dripping from it burns in an open flame, then carcinogens rise up with smoke and settle on the meat.

"Although the scope of our study is insufficient to make clear recommendations for cancer prevention through dietary modification, but with some understanding of the studied risk factors, clinicians and patients will be able to draw certain conclusions for themselves," Mariana Stern concluded.< /p>

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Prostate cancer: how to reduce the risk?

Researchers from the World Cancer Research Foundation have created eight new lifestyle recommendations for men that can reduce the risk of developing aggressive prostate cancer by several times.

The results of this study, conducted by scientists from the University of California World Cancer Center, led by Professor of Medicine and Biological Chemistry Lenore Arab, were published in the journal Nutrition and Cancer.

Studies have shown that physical activity and eating low-calorie foods (up to 125 kcal per 100 g of food) significantly reduce the risk of developing prostate cancer. So, eating no more than 500 g of red meat significantly reduces the risk of progression of prostate cancer.

The results and conclusions of the research team and its leadership suggest that even men diagnosed with prostate cancer can successfully control the progression of their disease and mitigate the aggressiveness of the oncological process through diet and lifestyle.

Studies have shown that the risk of developing prostate cancer decreased by 13% for each individual following the recommendations, which are as follows:

• Physical activity is required for at least half an hour during the day.
• Eat plenty of fruits and vegetables, whole grains, and legumes.
• You need to watch your weight.
• Sugary drinks and high-calorie foods should be limited.
• It is necessary to minimize or completely eliminate the use of alcoholic beverages.
• It is necessary to limit the consumption of salty foods, as well as red meat.
• Processed meat should be avoided.
• It is strictly forbidden to use supplements to protect against cancer.

In addition, previous research published in the American Cancer Society's journal Cancer has shown that exercise can also reduce the risk of prostate cancer.

Thus, diet is one of the important manageable risk factors for inflammation and prostate diseases, including cancer.

Risk factors and prevention of prostate cancer

The incidence of prostate cancer increases dramatically with increasing age. This disease is very rare in men younger than 50 years old, and after this age the incidence of prostate cancer increases exponentially.

The frequency of registration by age category in England and Wales increases from 8 per 1000 men aged 50-56 to 68 per 1000 men aged 60-64; 260 per 1000 men aged 70-74 and peaks at 406 per 1000 men aged 75-90.

In the same population, mortality in 1992 in groups aged 50-54, 60-64 and 70-74 years old was 4, 37 and 166 per 1000 men, respectively. At any age, the incidence of prostate cancer in blacks exceeds the frequency in whites.

Family history and genetics

Approximately 15% of men diagnosed with prostate cancer have a first-degree relative (i.e. brother, father) with the same disease. Approximately 9% of all prostate cancers may be the result of hereditary predisposition genes.

The statistics show that genetics is definitely a risk factor for prostate cancer. This disease is more common in some racial groups - in the US the disease is significantly more common in African Americans than in whites. A man has a much higher risk of developing cancer if his twin has it. A man whose brother or father has/had prostate cancer has twice the risk of developing the disease compared to other men.

Research indicates that two defective genes, BRCA 1 and BRCA 2, which are important risk factors for breast and ovarian cancer, are also implicated in prostate cancer risk.

In another study, scientists have found 7 new sites in the human genome that are associated with the risk of developing prostate cancer.

In a study published in April 2013 in the Journal of Clinical Oncology, scientists reported that a defective BRCA2 gene is associated with an aggressive form of prostate cancer, and that men who inherit the gene are more likely to have the rapidly spreading type prostate cancer. Scientists say these patients should be treated immediately after diagnosis with surgery or radiation therapy, rather than a "wait and see" approach.

The risk of prostate cancer is 2.1-4.9 times higher in men with Lynch syndrome compared to the general population.

The development of the prostate depends on the secretion of dihydrotestosterone (DHT) by the fetal testicles. Testosterone leads to the normal virilization of the structures of the Wolffian ducts and internal genital organs and acts with the help of the enzyme 5-alpha reductase to form dihydrotestosterone. DHT has 4-50 times higher affinity for the androgen receptor than testosterone and this DHT leads to normal prostate development.

Children who are born with a 5-alpha reductase disorder (due to changes in exon 5 of the 5-alpha reductase type 2 gene) are born with indeterminate genitalia but masculinize at puberty due to the testosterone surge at that time.

Clinical, imaging and histological studies of relatives of those born with 5-alpha reductase deficiency have demonstrated a small prostate gland with undetectable levels of prostate-specific antigen (PSA) and signs of prostatic epithelium.Long-term follow-up has shown that they do not develop either benign prostatic hyperplasia (BPH) or prostate cancer.

Other evidence that the degree of cumulative exposure of androgens to the prostate is associated with an increased risk of prostate cancer includes the following:

Men castrated before puberty have neither prostate cancer nor BPH.

Androgen deprivation in almost all forms leads to prostate involution, a drop in PSA levels, apoptosis of prostate cancer cells and epithelial cells, and a clinical response in patients with this disease.

The results of two large chemopreventive studies using 5-alpha reductase inhibitors (finasteride and dutasteride) demonstrated that intraprostatic androgens modulate the risk of prostate cancer. Both studies found a reduction in the overall risk of prostate cancer, although the risk of high-grade disease increased.

Environmental studies have found a correlation between serum levels of testosterone, especially DHT, and the overall risk of prostate cancer in African American, white, and Japanese men. However, data from prospective studies of the relationship between serum levels of sex hormones, including androgens and estrogens, did not support a direct relationship.

A pooled analysis of 18 prospective studies combining prediagnostic measurements of 3,886 men with prostate cancer and 6,438 control men found no association between risk of prostate cancer and serum concentrations of testosterone, estimated free testosterone, dihydrotestosterone sulfate, androstenedione, androstenedione glucuronide, estradiol or estimated free estradiol.

A caution in interpreting these data lies in the unknown degree of correlation between serum levels and levels in prostatic tissue. Androstenedione glucuronide may most accurately reflect intraprostatic androgen activity, and its measurement has not been associated with prostate cancer risk. This lack of association argues that risk stratification cannot be done on the basis of serum hormone concentrations.

The risk of developing and dying from prostate cancer is significantly higher in blacks, intermediate in whites, and lowest in Japanese. Differing data have been published regarding the etiology of these findings, but some evidence suggests that access to health care may play a role.

Incidence of new cases of prostate cancer by race and ethnicity in the United States

Prostate cancer is more common in North America, northwestern Europe, Australia, and the Caribbean. Less common in Asia, Africa, Central and South America.

The reasons for this phenomenon are not clear. More intensive screening in some developed countries may be responsible for part of this difference, but other factors such as differences in lifestyle (nutrition, etc.) also play a role.

An interesting observation is that although the incidence of latent prostate cancer is the same throughout the world, the incidence of clinical prostate cancer varies from country to country by more than 20 times. Previous environmental studies have shown a direct relationship between prostate cancer mortality and the average total calories of fat consumed by a country's population.

Studies of Japanese immigrants have shown that natural Japanese have the lowest risk of clinical prostate cancer, first-generation Japanese-Americans have an intermediate risk, and subsequent generations have a risk comparable to the US population. Animal models of explanted human prostate cancer have demonstrated a reduction in tumor growth rates in animals fed a low-fat diet. Data from many studies have found an association between dietary fat content and prostate cancer risk, although studies have not uniformly reached these conclusions.

In a review of published studies on the relationship between dietary fat and prostate cancer risk, approximately half found an increase in risk with increasing fat content, and half found no association. About half of the studies found an increase in risk with increased dietary fat, animal fat, monounsaturated and saturated fats, while about half of the studies found no such association. Only three studies reported a negative association between polyunsaturated fat intake and prostate cancer.

Animal fat seems to be associated with the highest risk of this disease. In a group of 384 patients with prostate cancer, the risk of disease progression to advanced stages was higher in men with a high fat intake.The announcement in 1996 in the United States that cancer deaths had declined led to speculation that this might be due to a reduction in dietary fat intake over the same time period.

Two studies were conducted that collected putative nutritional information, and all participants were advised to undergo a biopsy. The results showed that in 9,559 participants there was no association between any dietary supplement or any nutrient (including fat) and overall risk of prostate cancer, but the risk of high-grade cancer was associated with a high intake of polyunsaturated acids.

In a subgroup of 1,658 cancers and 1,803 controls, specific fatty acids were studied: docohexaenoic acid was associated with a risk of high-grade disease, while trans fatty acids 18:1 and trans fatty acids 18:2 were associated with risk high-grade illness is inversely proportional. These large-scale studies show the complex relationship between nutrients such as fat and prostate cancer risk.

The explanation for this possible association between prostate cancer and dietary fat is unknown. Several hypotheses have been put forward, including:

• Dietary fats can increase serum levels of androgens, thereby increasing the risk of prostate cancer. This hypothesis is supported by observations in South Africa and the United States, where changes in dietary fat intake altered urinary and serum androgen levels.
• Some types of fatty acids or their metabolites can initiate or contribute to the development of prostate carcinoma. The evidence for this hypothesis is conflicting, but one study has confirmed that linoleic acid (an omega-6 polyunsaturated fatty acid) can stimulate prostate cancer cells, while omega-3 fatty acids inhibit cell growth.
• An animal model observation has shown that the male offspring of pregnant rats fed a high-fat diet develop prostate cancer at a higher rate than the offspring of rats fed a low-fat diet. This observation may explain some of the differences in prostate cancer rates and mortality among ethnic groups; during the first trimester, androgen levels in pregnant blacks are higher than those in whites.

Other studies have shown that vitamin D deficiency, a diet high in red meat, may increase the risk of prostate cancer.

Dairy products and calcium intake

A meta-analysis of ten studies found that men with high intakes of dairy and calcium were more likely to develop prostate cancer than men with lower intakes, although the increase in risk was small.

Use of multivitamins

Regular multivitamin intake has not been associated with a risk of early or localized prostate cancer. However, a large study (295,344 men) found a statistically significant increase in the risk of advanced or fatal prostate cancer among men with multivitamin overuse.

Medicines

Some studies suggest that there may be an association between daily use of anti-inflammatory drugs and the risk of prostate cancer.

The study found a clear link between obesity and an increased risk of prostate cancer, as well as a higher risk of metastasis and death in people with obesity and prostate cancer.

A meta-analysis has shown that the risk of aggressive, fatal prostate cancer increases by 12% per 10 cm increase in height.

Sexually transmitted diseases

Men with a history of gonorrhea have a higher risk of developing prostate cancer, according to a University of Michigan study.

Folic acid

Dietary supplementation of 1mg folic acid has been associated with an increased risk of prostate cancer. However, dietary and plasma folic acid levels in men not taking multivitamins were inversely associated with the risk of this disease. These data highlight the potentially complex role of folic acid in prostate carcinogenesis.

Cadmium exposure

Earlier studies have found a link between cadmium and prostate cancer, but better designed studies have failed to confirm it.

Dioxin is a herbicide contaminant used in Vietnam. This agent is a substitute for many components of herbicides used in agriculture. A review of the relationship between dioxin and prostate cancer risk found that the relationship between dioxin and prostate cancer is inconclusive.

Agent Orange

Veterans exposed to Agent Orange have a 48% higher rate of prostate cancer recurrence after surgery compared to their non-exposed peers.Another study found that Vietnam War veterans who were exposed to Agent Orange had a significantly higher risk of prostate cancer and a risk of developing a more aggressive form of the disease.

Most studies have not found an association between smoking and prostate cancer risk. Some studies have associated smoking with a possible small increase in the risk of death from prostate cancer, but these findings need to be confirmed in other studies.

Smoking has been shown to increase the recurrence rate after prostate cancer surgery.

It's never too late to quit smoking. Giving up this bad habit has a lot of benefits for the body.

Exposure to toxins in the workplace

There is evidence that firefighters are exposed to toxic combustion products that can increase the risk of prostate cancer.

Inflammation of the prostate

Some studies have shown that prostatitis may be associated with an increased risk of prostate cancer, but other studies have not found such an association. Inflammation is often found in prostate tissue samples that also contain cancer. The connection between the two has not yet been elucidated, but it is an area of active research.

Vasectomy

Some studies have shown that men who have had a vasectomy (ligation or removal of a piece of the vas deferens) have a slightly increased risk of prostate cancer. But other studies have not found such an increase. Research into this possible connection is ongoing.

Prevention of prostate cancer

Can prostate cancer be prevented?

Because the exact cause of prostate cancer is not known, it is currently impossible to prevent most cases of the disease. Many risk factors - such as age, race, family history - cannot be modified. But based on the knowledge of other risk factors, there are some measures that can reduce the risk of prostate cancer.

Healthy food

There is some evidence that a healthy diet low in fat and high in fruits and vegetables (called the Mediterranean diet) can help reduce the risk of prostate cancer, although this has not been proven specifically.

To reduce the risk, you need to:

• Follow a low-fat diet. Foods that contain fats are meat, nuts, oils and dairy products such as milk and cheese.

While there is no proven link between excess fat intake and prostate cancer, reducing fat intake has other clear benefits, such as weight control and heart health.

To reduce the amount of fat you eat, you should limit fatty foods or choose low-fat types.

• Eat more vegetable fats than animal fats. Animal fats in studies were more likely to be associated with an increased risk of prostate cancer.
• Increase the amount of fruits and vegetables you eat. Fruits and vegetables are rich in vitamins and nutrients that are believed to reduce the risk of prostate cancer, although studies have not proven that any single nutrient is guaranteed to reduce the risk of this disease.
• Eat fish. Fatty fish - such as salmon, tuna, and herring - contain omega-3 fatty acids, which have been linked to a reduced risk of prostate cancer.

Another source of omega-3 fatty acids is flax seeds.

• Reduce dairy.
• Limit calcium supplementation (this does not mean that people who are being treated for prostate cancer should not take calcium supplements if their doctor recommends them).

Maintaining a healthy weight

Men with a BMI greater than 30 may have an increased risk of developing prostate cancer. They need to work on losing weight. If a man is at a healthy weight, he should maintain it through exercise and a healthy diet rich in fruits, vegetables, and whole grains.

Physical activity

Research has shown that men who exercise may have a lower risk of prostate cancer. Exercise has many other health benefits and may reduce the risk of heart disease and other cancers. They also help maintain a healthy weight or aid in weight loss.

Vitamins, minerals and other supplements

Some early research has shown that taking certain vitamin or mineral supplements may reduce the risk of prostate cancer. Vitamin E and the mineral selenium have been of particular interest.

To study the possible impact of selenium and vitamin E on the risk of prostate cancer, doctors conducted a study called SELECT.The men in this large study took one or both of these supplements or an inactive placebo every day for 5 years.

In this study, neither vitamin E nor selenium reduced the risk of prostate cancer. In fact, men who took vitamin E were later found to have a slightly increased risk of prostate cancer. In men who had lower levels of selenium at the start of the study, supplementation of this mineral did not change the risk of prostate cancer. Men who had higher baseline levels had an increased risk of high-grade prostate cancer.

Some research is currently looking into the possible impact of soy proteins (called isoflavones) on prostate cancer risk. The results of these studies are not yet available.

Medicines

Some medications can help reduce the risk of prostate cancer.

5-alpha reductase inhibitors

5-alpha reductase is an enzyme in the body that converts testosterone to dihydrotestosterone, the main hormone that causes prostate growth. Drugs called 5-alpha-redctase inhibitors block this enzyme and prevent the formation of DHT.

Two 5α-reductase inhibitors are currently used to treat BPH:

Large studies have been conducted to investigate whether these drugs can be used to reduce the risk of prostate cancer. In these studies, men taking any of these drugs were less likely to develop prostate cancer after several years than men taking an inactive placebo.

When the results were examined more closely, it was found that men taking these drugs had fewer low-grade prostate cancers, but slightly more moderate-to-high grade prostate cancers. Medium to high grade prostate cancer is more likely to grow and spread than low grade prostate cancer.

These drugs can cause sexual side effects such as decreased sex drive and impotence. But they can help with urinary problems or BPH incontinence.

While these drugs are safe, they are not approved by the FDA for the prevention of prostate cancer.

Some studies show that men who take aspirin daily for a long time may have a lower risk of developing prostate cancer and dying from the disease. But more research is needed to show that the possible benefits outweigh the risks.

Long-term use of aspirin may have side effects, including an increased risk of bleeding from the gastrointestinal tract. While aspirin also has other health benefits, it is currently not recommended by doctors for the sole purpose of preventing prostate cancer.

A study found that statins, which are used to lower cholesterol levels, may reduce the risk of developing prostate cancer.

Other medicines and conditions that may lower your risk of prostate cancer

• Diabetes mellitus - reduces risk by 15-28%.
• Systemic lupus erythematosus - reduces the risk by a third.
• HIV - reduces risk by 30-31%.
• Parkinson's disease - reduces risk by 20%.
• Paracetamol (aggressive prostate cancer) - reduces risk by 38% when taken more than 30 tablets per month.
• Warfarin reduces risk by 17-31%.