Abstract
In an international comparison of recent mortality statistics among G7 countries, Japan had the longest average life expectancy, primarily due to remarkably low mortality rates from ischemic ...heart disease and cancer (particularly breast and prostate). As recently as the 1960s, life expectancy in Japan was the shortest among the G7 countries, owing to relatively high mortality from cerebrovascular disease—particularly intracerebral hemorrhage—and stomach cancer. Mortality rates for these diseases subsequently decreased significantly while the already low rates for ischemic heart disease and cancer also decreased, resulting in Japanese life expectancy becoming the longest. The low mortality rates from ischemic heart disease and cancer are thought to reflect the low prevalence of obesity in Japan; low intake of red meat, specifically saturated fatty acids; and high intakes of fish, specifically n-3 polyunsaturated fatty acids, plant foods such as soybeans, and nonsugar-sweetened beverages such as green tea. The decreasing mortality rates from cerebrovascular disease are thought to reflect the increases in animal foods, milk, and dairy products and consequently in saturated fatty acids and calcium, together with a decrease in salt intake which may have led to a decrease in blood pressure. This decrease in salt and highly salted foods also seems to account for the decrease in stomach cancer. The typical Japanese diet as characterized by plant food and fish as well as modest Westernized diet such as meat, milk and dairy products might be associated with longevity in Japan.
Because gastric cancer is still the most common cancer, its prevention is one of the most important aspects of Japan's cancer control strategy. Observations among Japanese immigrants in the USA and ...Brazil based on the geographic differences, the trend in cancer incidence with time, and the change in incidence patterns indicate that gastric cancer is closely associated with dietary factors, such as the intake of salt and salted food. In international and intra‐Japanese ecological studies, the average salt excretion level, estimated using randomly selected 24‐h urine samples in each population, was closely correlated with gastric cancer mortality. Several case–control and cohort studies, including the author's recent works, have shown that a higher intake of some traditional salt‐preserved food and salt per se, which was estimated using a validated food‐frequency questionnaire, was associated with a risk of gastric cancer. While salted food intake may increase the risk of Helicobacter pylori infection, it can also act synergistically to promote the development of gastric cancer. Based on substantial evidence about the association between salt and salted food intake and the risk of gastric cancer from ecological, case–control, and cohort studies conducted in Japan and other countries, as well as mechanistic plausibility, dietary modification involving less salt and salted food intake is a practical strategy with which to prevent gastric cancer. (Cancer Sci 2005; 96: 1–6)
Over the last 60 years, Japanese people have experienced a rapid and drastic change in lifestyle, including diet. Suspicions have been raised that so‐called ‘Westernization’, characterized by a ...high‐calorie diet and physical inactivity, is associated with increasing trends in the incidence of cancer of the colon, liver, pancreas, prostate, and breast, as well as type 2 diabetes. Epidemiological evidence from our prospective study, the Japan Public Health Center‐based Prospective (JPHC) study, and systematic literature reviews generally support the idea that factors related to diabetes or insulin resistance are associated with an increased risk of colon (mostly in men), liver, and pancreatic cancers. These cancers are inversely associated with physical activity and coffee consumption, which are known to decrease the risk of type 2 diabetes. The suggested mechanism of these effects is that insulin resistance and the resulting chronic hyperinsulinemia and increase in bioavailable insulin‐like growth factor 1 (IGF1) stimulate tumor growth. In contrast, associations with diabetes are less clear for cancer of the colon in women, and breast and prostate, which are known to be related to sex hormones. The effect of insulin resistance or body fat on sex‐hormone production and bioavailability may modify their carcinogenic effect differently from cancers of the colon in men, and liver and pancreas. In conclusion, there is substantial evidence to show that cancers of the colon, liver, and pancreas are associated with insulin resistance, and that these cancers can be prevented by increasing physical activity, and possibly coffee consumption.
(Cancer Sci 2010; 101: 1073–1079)
The Japan Public Health Center-based prospective Study conducted a baseline survey for 140 000 registered residents aged 40-69 years within 11 public health center areas nationwide in 1990-94. Five- ...and 10-year follow-up surveys were conducted to update information on lifestyle habits and health conditions. In total, 130 000 participants responded to at least one of the three questionnaire surveys, and 78 000 to all three. In addition, 60 000 participants provided blood samples on at least one of the two sampling times, and 23 000 on both. The subjects have been followed for vital status and the occurrence of cancer and other diseases. As of December 2011, 24 000 deaths have been documented, as well as 17 000 cases of cancer, 6000 cases of stroke and 1100 cases of myocardial infarction. We have tested the association between potential causal factors and the incidence of or mortality from cancer and other diseases, and published >250 papers to date. Typical dietary habits in Japan are high consumption of soy/isoflavones, fish/n-3 fatty acids, salt/salted foods and green tea, and low consumption of red meat and saturated fat. This paper briefly summarizes the observed associations of these foods/nutrients with cancer, cardiovascular diseases and diabetes. The Japan Public Health Center-based prospective Study is scheduled to conduct active follow-up for a total of 30 years, and we plan to publish additional evidence on the potential causes of a shorter life and major disease occurrence.
Timothy J Key and colleagues describe the evidence linking diet and nutrition to cancer risk, concluding that obesity and alcohol are the most important factors
Although our understanding of the etiology of breast cancer has improved, many well‐known risk factors are not modifiable and present knowledge has proved insufficient to allow the disease to be ...overcome. Indeed, incidence and mortality among Japanese women have increased over the past three decades. Here, we review epidemiological evidence from our cohort and case–control studies among Japanese women in comparison with other published findings. Our studies confirm the important role of established factors derived primarily from Western populations, such as menstrual and reproductive factors, anthropometric factors, physical activity, and alcohol intake, in the development of breast cancer. In addition, we provide further evidence to better understand the role of traditional Japanese foods in the etiology of breast cancer. Our cohort study found that a higher intake of isoflavone and higher levels of plasma genistein, but not daidzein, were associated with a decreased risk of breast cancer. Our case–control studies reveal a dose–response pattern for these compounds; specifically, decreased risk as women move from “no” to “moderate” intake and leveling off thereafter. In addition, gene–environment interactions have been revealed in the effects of isoflavones. The evidence reviewed suggests that isoflavone has a protective effect against breast cancer in Asian populations. Conversely, our cohort study did not observe an inverse association between breast cancer risk and the intake of green tea and/or the plasma level of tea polyphenols, but we did find an association between increased risk and active and passive smoking. In conclusion, based on current knowledge, primary prevention according to individual lifestyle modification should focus on alcohol intake, weight control, physical activity, and tobacco smoking. (Cancer Sci 2011; 102: 1607–1614)
Diet and the risk of gastric cancer: review of epidemiological evidence Tsugane, Shoichiro; Sasazuki, Shizuka
Gastric cancer : official journal of the International Gastric Cancer Association and the Japanese Gastric Cancer Association,
06/2007, Letnik:
10, Številka:
2
Journal Article
Recenzirano
Odprti dostop
There are geographic and ethnic differences in the incidence of gastric cancer around the world as well as with its trends for each population over time. The incidence patterns observed among ...immigrants change according to where they live. All of these factors serve to indicate the close association of gastric cancer with modifiable factors such as diet. This review presents epidemiological evidence on the association between dietary factors and gastric cancer based on previous systematic reviews and subsequent updates. Infection with Helicobacter pylori is a strong and established risk factor of gastric cancer but is not a sufficient cause for its development. Substantial evidence from ecological, case-control, and cohort studies strongly suggests that the risk may be increased with a high intake of various traditional salt-preserved foods and salt per se and decreased with a high intake of fruit and vegetables, particularly fruit. However, it remains unclear which constituents in fruit and vegetables play a significant role in gastric cancer prevention. Among them, vitamin C is a plausible candidate supported by a relatively large body of epidemiological evidence. Consumption of green tea is possibly associated with a decreased risk of gastric cancer, although the protective effects have been, for the most part, identified in Japanese women, most of whom are nonsmokers. In contrast, processed meat and N-nitroso compounds may be positively associated with the risk of gastric cancer. In conclusion, dietary modification by reducing salt and salted food intake, as well as by increasing intake of fruit and vitamin C, represents a practical strategy to prevent gastric cancer.
Human height is a representative phenotype to elucidate genetic architecture. However, the majority of large studies have been performed in European population. To investigate the rare and ...low-frequency variants associated with height, we construct a reference panel (N = 3,541) for genotype imputation by integrating the whole-genome sequence data from 1,037 Japanese with that of the 1000 Genomes Project, and perform a genome-wide association study in 191,787 Japanese. We report 573 height-associated variants, including 22 rare and 42 low-frequency variants. These 64 variants explain 1.7% of the phenotypic variance. Furthermore, a gene-based analysis identifies two genes with multiple height-increasing rare and low-frequency nonsynonymous variants (SLC27A3 and CYP26B1; P
< 2.5 × 10
). Our analysis shows a general tendency of the effect sizes of rare variants towards increasing height, which is contrary to findings among Europeans, suggesting that height-associated rare variants are under different selection pressure in Japanese and European populations.
The health impact of alcohol drinking, cigarette smoking and obesity differs between Asian and Western countries. The epidemiology of cancer and death related to these lifestyles are described in ...this article. In Japan, heavy alcohol drinking and cigarette smoking are rather high in men. While there is a worldwide anti‐smoking policy, Japan is still on the way to aiming at this goal, and this delay in health promotion has maintained the high impact of smoking, whether active or passive, on people's health in that country. Public health policy should focus more strongly on the control of smoking and heavy drinking, especially among men. Maintaining the consumption of alcohol at a level below 46 g a day in men and 23 g a day in women appears to minimize the risks of mortality and cancer in the Japanese population. On the other hand, the obesity rate is low and being underweight is common both in men and women. Proportions of cancer attributable to a body mass index of 25 or more are only 0.5% in men and 1.1% in women. Given that many previous studies in Japanese and Asian populations have associated a low body mass index with an increased risk of cancer, the impact of being underweight—not only obese—may warrant further investigation.
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