Recently, the latest research report of the American Association for Cancer Research's official journal CA:Clinicians pointed out that in 2012, nearly 4% of the world's cancers (544,300 cases) were derived from obesity, and there is sufficient evidence that obesity and 13 cancers are highly risky. Related, including postmenopausal breast cancer, colorectal cancer, endometrial cancer, esophageal adenocarcinoma, gallbladder, kidney cancer, liver cancer, meningioma, multiple myeloma, ovarian cancer, pancreatic cancer, gastric cardia cancer, and thyroid cancer. In addition, there are three types of cancer, including advanced prostate cancer, oral cancer, and throat cancer that may also be associated with obesity.
World population obesity status
Since the 1970s, the prevalence of overweight and the associated cancer burden worldwide have been rising. Between 1975 and 2016, the prevalence of male obesity (BMI ≥ 30 kg / m2) quadrupled from 3% to 12%, and women more than doubled, from 7% to 16%, plus With population growth, the number of obese adults worldwide has more than tripled (from 100 million to 671 million). In 2016, about 40% of adults and 18% of children (aged 5 to 19) were overweight, equivalent to nearly 2 billion adults and 340 million children. Among them, in high-income western countries, the absolute increase in obesity among men and boys is the largest. In Central Asia, the Middle East and North Africa, the absolute increase in obesity among women and girls is also the highest.
The rate of overweight at the same time in almost all countries is increasing, and the analysis suggests that it may be due to the introduction of “Western lifestylesâ€: energy-intensive, malnourished foods and reduced frequency of physical activity.
Obesity is associated with cancer risk
The study pointed out that in 2012, overweight accounted for 3.9% (544,300 cases) of all cancer causes, of which low-income countries accounted for less than 1%, while the proportion of some high-income countries in the West, Middle East and North Africa was 7% or 8%. And according to the conclusions reached by the International Agency for Research on Cancer (IARC) Body Obesity in 2016, there is sufficient evidence that body obesity is associated with 13 cancer risks, most recently the World Cancer Research Foundation and the American Cancer Institute (WCRF/AICR). The expert report listed early prostate cancer as a possible association with oral cancer and throat cancer.
The causal relationship between overweight and cancer risk is supported by a large body of epidemiological evidence that there is a strong dose-response relationship between overweight and cancer risk, and experimental studies have suggested multiple Reasonable biological mechanism.
Table 1 summarizes current epidemiological evidence that there is a link between human lipids and the risk of 15 different cancer sites. The data is based primarily on the European population living in high-income countries.
The proportion of cancer caused by obesity varies from 0.4% to 8.2% in different countries.
Several studies used population-attributable score (PAF) estimates to quantify the proportion of cancer burdens globally due to overweight, and the study included a meta-analysis of BMI and cancer incidence, as well as overweight specificity by age and gender. National prevalence rate. In a recent study, Pearson Stuttard et al. studied cancer incidence PAF for 12 cancer types from 175 countries in nine regions of the world and set a 10-year lag between cancer determination and cancer development. . The study found that about 544,300 cancers (3.9% of all cancers worldwide) in 2012 were attributable to excess body weight in 2002.
The differences in countries vary from 0.4% to 8.2%. The countries with the highest PAF are Egypt (8.2%), Mongolia (8%), Puerto Rico (7.7%), Saudi Arabia (7.5). %), Russia (7.3%), Fiji (7.2%), Czech Republic (7.2%), United States (6.9%), Jordan (6.9%), and 6 Middle East and nearby North African countries (both > 6.5%). Countries with PAF <=1% include Ethiopia (1.0%), India (0.9%), Uganda (0.8%), Bangladesh (0.7%), Malawi (0.4%) And 10 other countries, these countries are located in sub-Saharan Africa, South Asia or Southeast Asia.
Obesity-caused cancer varies greatly in location, gender, and region
PAF caused by overweight varies greatly depending on the location of the cancer
For example, female overweight causes approximately one-third of endometrial cancer (98,400 out of 317,000 cases) and esophageal adenocarcinoma (2200 out of 7300 cases), while for ovarian cancer (235,000) The proportion of 9100 cases in the example is only 4%. In men, approximately 29% of esophageal adenocarcinomas can be attributed to overweight, while pancreatic, colorectal or thyroid cancers are approximately 6%.
Cases of cancer caused by obesity vary widely between men and women
The total number of cancer cases caused by obesity in women (368,500 cases) is twice that of men (175,800 cases), with breast cancer accounting for the largest proportion (114,800 cases, 31%), followed by endometrial cancer (98,400 cases). , 27%) and colorectal cancer (42,300 cases, 12%). In contrast, the largest proportion of men were liver cancer (54,600, 31%), followed by colorectal cancer (42,200, 24%) and kidney cancer (37,400, 21%).
Cancers caused by overweight in different countries are very different
Almost half of the cancer cases caused by obesity occur in high-income western countries (252,500, 46%), although the rate of overweight is relatively low, and the eastern and southeastern regions are ranked second because of their large population and high burden of liver cancer ( 87,600 cases, 16%). Central and Eastern Europe ranked third (77,700, 14%), followed by Latin America and the Caribbean (9%), Central Asia, the Middle East and North Africa (6%).
The cancer situation caused by overweight in each region is also very different. In 5 out of 9 regions, female breast cancer is the largest type of cancer - South Asia (30%), Sub-Saharan Africa (30%), Latin America. And the Caribbean (26%), high-income Western countries (25%); in East Asia and Southeast Asia, Oceania and high-income Asia Pacific, the highest incidence of liver cancer, 42%, 30% and 22%. Female-specific cancers, such as breast, endometrial and ovarian cancer, have a particularly high incidence in the highlands (50%), sub-Saharan Africa (53%) and South Asia (51%) in high-income Asia Pacific The incidence rate is low in the region (22%) and in East Asia and Southeast Asia (26%).
13 cancers are highly associated with obesity and evidence is sufficient
Breast cancer
In 2012, about 7% of postmenopausal (50 years and older) breast cancer (114,800 cases) was attributable to overweight, compared with North America and Europe (10%), Asians (37%) were at greater risk Large, this risk will continue to increase in women who have never had menopausal hormone therapy (MHT) or who have previously used but are not currently using it, but this conclusion is not appropriate for HR-negative or triple-negative cancers.
Waist circumference is associated with an increased risk of postmenopausal breast cancer. For every 10 cm increase in waist circumference, the risk of postmenopausal breast cancer increases by 6%. In addition, adult weight gain is also associated with increased risk. In a 40-year female follow-up study, women over the age of 18, who were chronically over 20 kg (about 44 lbs) or more, had a 37% increased risk of postmenopausal breast cancer, but in the early stages (18 - 30 years old), weight gain was inversely associated with risk of postmenopausal breast cancer (every 5 units increase in BMI, risk was reduced by 18%).
Colorectal cancer
In 2012, 7% of women with colorectal cancer (42,300) and 6% of men with colorectal cancer (42,200) were attributable to excessive body weight. For every 5 units of male BMI, the risk increases by 8%. For every 5 units of female BMI, the risk increases by 5%. The relationship between adult weight gain and colorectal cancer risk is more closely related to women.
In addition, for every 0.1 unit increase in waist-to-hip ratio, the risk of colon cancer increases by 20%. In a study comparing various fat indicators, after adjusting for factors such as BMI, waist circumference, percentage of body fat, and subcutaneous fat, only visceral adipose tissue was a determinant of colorectal cancer, which was statistically significant, indicating viscera. The adverse effects of metabolism caused by increased fat may mediate the link between obesity and cancer risk.
Endometrial cancer
Worldwide, overweight accounts for approximately 31% of endometrial cancers in 2012 (98,400 cases). Compared with normal-weight women, the risk of overweight people is linearly increased. The risk of BMI is between 25 and 30, and the risk is linearly increased by 1.5 times. The level of obesity (BMI is between 30 and 35) is 2. 5 times, grade 2 obese (BMI between 35 and 40) is 4.5 times, and grade 3 obese (BMI is above 40) is 7.1 times.
For every 5 units increase in body mass index, the risk of endometrial cancer increases by 50%. Women who have never used MHT are at a higher risk than women who use MHT. For every 5 units increase in the former BMI, the risk increases by 90%, and the latter is 18%. The risk of type I tumors (mainly endometrioid adenocarcinoma) (every 2 units increase in BMI, increased risk by 16% to 23%) than type II tumors (slurry cells and mixed cells) (every 2 units increase in BMI, The risk increases by about 12%). For every 10cm increase in waist circumference, the risk increases by 30, and for every 0.1 unit increase in waist-to-hip ratio, the risk increases by 21%. An analysis of seven prospective studies showed that for every 5 units of body mass index between 18 and 25 years old, the risk of endometrial cancer increased by 42%.
Esophageal adenocarcinoma
In 2012, nearly 30% (11,300) of esophageal adenocarcinomas worldwide were attributable to excessive body weight. After adjusting for smoking status, for every 5 units increase in BMI, the risk increased by 48%. Among non-smokers, the correlation is stronger, the risk increases by 62% for every 5 units of BMI, the risk of esophageal adenocarcinoma increases by 34% for every 10cm increase in waist circumference, and the risk increases for every 0.1 unit increase in waist-to-hip ratio. 38%.
Gallbladder cancer
In 2012, approximately 13% of women with gallbladder cancer (13,000 cases) and 10% of men with gallbladder cancer (7400 cases) were attributable to excessive body weight. For every 5 units of BMI, the risk of gallbladder cancer increased by 25%.
Kidney cancer
In 2012, about 20% of kidney cancers worldwide (25,200 women and 37,400 men) were caused by excessive body weight. For every 5 units of BMI, the risk of kidney cancer increased by 30%, and the waist circumference increased by 10 cm. The risk of kidney cancer increased by 11%, and the risk of kidney cancer increased by 26% for every 0.1 cm increase in waist-to-hip ratio.
Liver cancer
In 2012, about 10% of male liver cancer (54,600 cases) and 14% of female liver cancers (30,200 cases) worldwide are attributable to excessive body weight. For every 5 units of BMI, the risk of liver cancer increases. %. Europeans (for every 5 units increase in BMI, a 59% increase in risk) appear to be more relevant than Asians (every 5 units increase in BMI, an 18% increase in risk).
Meningioma
Meningioma is one of the most common primary central nervous system tumors, accounting for 36% of global cases. Compared with normal weight, the risk of meningioma in overweight people is increased by 20%, and the risk of meningiomas in obese people is increased by 50%.
Multiple myeloma
Worldwide, women with multiple myeloma caused by overweight in 2012 accounted for 7% (4,500 cases), and in men this proportion was 9% (4,400 cases). A comprehensive analysis of three large prospective cohort studies found that for people aged 18 to 30, the risk increased by 28% for every 5 units increased by BMI.
Ovarian cancer
In 2012, about 4% (9100 cases) of ovarian cancer in the world was caused by excessive body weight. For every 5 units of body mass index increase, the risk of ovarian cancer increased by 6%, similar to breast cancer and endometrial cancer. The association seems to be limited to women who have never used MHT (Table 1). Some studies have shown that higher BMI only increases the risk of less common subtypes such as endometrial cancer and mucinous carcinoma; however, further research is needed to confirm the association between these subtypes.
Pancreatic cancer
Worldwide, male pancreatic cancer caused by overweight is about 6% (10,300 cases), and in women, this percentage is 7% (11,200 cases). For every 5 units of BMI, the risk of pancreatic cancer increases by 10%, the risk increases by 11% for every 10 cm of waist circumference, and the risk increases by 19% for every 0.1 units of waist-to-hip ratio. The weight of people aged 18 to 21 is overweight. It seems to be related to an increased risk of pancreatic cancer in later life.
Gastric and cardiac cancer
Overweight causes approximately 9% (6400 cases) of male gastric cardia cancer and 11% (2900 cases) of female gastric cardia cancer. Obesity increases the risk of gastric cancer caused by the risk of gastric cardia cancer. About 27% of global gastric cancer causes are sources. Here, for every 5 units of BMI, the risk of gastric cardia cancer increases by 23%.
Thyroid cancer
Obesity in men and women leads to 7% of thyroid cancer (14,800 cases) and 6% (3900 cases). For every 5 units of BMI, the risk of thyroid cancer increases by 6%. Overweight in 18 to 30 years old seems to be inferior to the later years. Increased risk of developing thyroid cancer (every 5 units increase in BMI, risk increased by 13%).
Cancer that may be caused by obesity
Oral and throat cancer
There is growing evidence that obesity may increase the risk of oral and throat cancer. A comprehensive analysis of 20 cohort studies showed that for non-smokers, for every 5 units of body mass index, the risk of developing these cancers increased by 15%.
Prostate cancer (late stage)
There is growing evidence that obesity may increase the risk of advanced or fatal prostate cancer, and for every 5 units of body mass index, the risk of advanced prostate cancer increases by 8%.
Why obesity leads to an increased risk of cancer
Scientists have now proposed various mechanisms to explain how body fat affects cancer risk. Changes in the endocrine system, including peptide metabolism hormones and sex steroid hormones, as well as chronic inflammation are the most studied directions. Studies have shown that the effects of fat on metabolic hormones affect many types of cancer. The effects on steroids affect cancers with high hormone sensitivity, and local inflammation is associated with certain cancers.
Excessive obesity leads to insulin resistance, which in turn leads to hyperinsulinemia, which induces inhibition of intrahepatic insulin-like growth factor (IGF) binding protein production, thereby increasing circulating insulin and bioavailable IGF-1 concentrations, insulin receptor and IGF-1. Activation of the receptor triggers an intracellular signaling cascade that promotes tumor development and spread. A large number of epidemiological studies have found that insulin and/or IGF-1 pathways are particularly relevant for colorectal cancer, prostate cancer, breast cancer, and endometrial cancer. .
In addition, adipose tissue acts as an endocrine organ, affecting the synthesis and bioavailability of sex hormones. Aromatase expressed by adipose tissue converts androgens into estrogens and converts these hormones from the less active form (androstenedione, estrone) to the highly active form (testosterone, estradiol). In addition, hyperinsulinemia and increased biological activity of IGF-1 result in decreased liver synthesis and blood levels of sex hormone binding globulin, which in turn increases bioavailable free estradiol and testosterone. Sex steroids are thought to be a mediator between obesity and breast cancer and endometrial cancer risk, and may also be associated with prostate cancer and colorectal cancer risk. In a large comprehensive analysis combining eight prospective studies, the relationship between BMI and postmenopausal breast cancer risk can almost be explained by an increase in estradiol levels and an increase in BMI levels.
Adiponectin is the most studied adipokines in cancer risk, and serum adiponectin levels are inversely related to body mass index. Studies have found that adiponectin may have an indirect effect on tumor development by sensitizing cells to insulin or through anti-inflammatory effects. Adiponectin may also directly exert anti-tumor effects by regulating metabolism, inflammation, and cell cycle signaling pathways. However, observational studies of the relationship between pre-diagnostic circulating adiponectin levels and several cancer risks have yielded mixed results.
Adipose tissue produces a variety of pro-inflammatory molecules, including tumor necrosis factor alpha and interleukin-6, which can cause local inflammation of adipose tissue and affect other organs. Low-grade chronic inflammation, usually found in obese people, and making this type of population susceptible to certain types of cancer by creating a tissue environment that produces oxidative stress, stimulates DNA damage, increases cell proliferation, and inhibits apoptosis. . Several examples of local inflammation associated with cancer risk include association of nonalcoholic fatty liver with liver cancer, association of chronic acid reflux with esophageal adenocarcinoma, and the like.
The actual cancer burden in the future caused by obesity may be greater
The increase in wealth is the most obvious systemic driver of obesity, and the more affluent economic transformation creates a convenient environment for obesity. For every $10,000 increase in average national income, the adult's body mass index will increase by 0.4. However, economic prosperity is not always associated with overweight, and high-income Asia-Pacific countries have low obesity rates (range 4%-7%), which is likely to benefit from local traditional eating habits and often needed The daily traffic pattern of walking, while in some low-income countries, such as some Pacific island countries (40%-65%) and Egypt (43% women and 24% men), the obesity rate is very high.
It should be noted that the researchers said that due to the PAF calculation method, the true impact of obesity on the cancer burden may be underestimated. According to the American Cancer Society, considering the prevalence of overweight in high-income countries and the increasing prevalence of low- and middle-income countries, the actual future cancer burden caused by obesity may be even greater, and 21.7 million new is expected by 2030. A cancer case.
The World Health Organization has included a measure to curb obesity growth in its 2025 goal to address the global burden of growing noncommunicable diseases, including cancer. Interventions include legislation prohibiting the use of trans fats in food, taxing sugary drinks, subsidizing fruit and vegetable intake, limiting package size, providing convenient public open spaces, and supporting walking and cycling infrastructure.
The lock channel is one of the most important thing for greenhouse, it can lock the film ,shading net ,insect net .
It is hot galvanized or aluminum material.
We have different thickness.
Welcome to contact us
Lock Channel,Greenhouse Lock Channel,Channel Lock,greenhouse profile
JIANGSU SKYPLAN GREENHOUSE TECHNOLOGY CO.,LTD , https://www.skyplantgreenhouse.com