Do staples and meat decide life and death?

Original title: Do Staples and Meat Determine Life and Death
Interviewed Experts:
American Medical College Fellow, Director of the Department of Nutrition at Harvard University Hu P. Chang
Liu Simin, Tenure Professor of Medicine and Epidemiology, Brown University, USA
Fan Zhihong, Associate Professor, School of Food Science and Nutritional Engineering, China Agricultural University
Recently, a wave of nutrition in China and the world. On August 29th The Lancet, the UK's authoritative medical journal, published three large epidemiological observational research papers from the same team. The study, conducted by Canadian academics, looked at nutrient intake in 135,000 people in 18 countries, as well as deaths from cardiovascular disease and various causes. The study followed an average of 7.4 years and used statistical methods to try to find out if diet was related to the above-mentioned diseases.
paper found that eating enough vegetables, fruits and legumes is good for your health. This result is consistent with known health concepts and is not controversial. The other two papers caused a stir. The study found that high carbohydrate intake was associated with an increase in overall mortality, while a high-fat diet was associated with a decrease in total mortality. The results upended the long-standing belief that "fat is harmful" and "a healthier diet with low fat" quickly went on the Internet. There have been many out-of-context, over-interpreted reports on websites at home and abroad. These "problem" articles cheered those who liked to eat oil and fat, and excited those who advocated eating less staple food.
experts after rational analysis, said that the study itself there are some problems, coupled with some people do not understand the specific content, eager to come to an extreme conclusion, this misleading may affect thousands of people.
Focus One
Study: Eating too many staple foods at high risk of premature death
Experts: Chinese staples eat the right amount
Chinese like to eat staples, while staples are carbohydrate-rich "big households". The study found that the highest group (77.2%) was 28% higher and 36% higher in total mortality and non-cardiovascular disease mortality when carbohydrate energy ratios were divided into five groups from low to high. As a result, the findings have evolved a view: "It's not good to eat more carbs or staples."
study also showed that Carbohydrate energy supply was relatively high in China, with respondents 67.0%, 17.7% and 15.3% on average, and 43% of Chinese respondents had carbohydrate energy ratios of more than 70% and more than 77% over 60%, respectively.
experts have disputed China's data. "I'm afraid the results of this article only represent the living conditions Chinese 30 years ago." Fan Zhihong, an associate professor at the School of Food Science and Nutritional Engineering at The Agricultural University of China, said the study, which covered more than 40,000 Chinese respondents, was mostly primary or secondary school culture, engaged in moderate or heavy manual labor, with low-income manual workers as the main subjects of the study.
" into specific food, we will be better judged. For an adult woman with an energy need of 1,800 kca per day, for example, 77.2% of carbohydrate contribution ratios equivalent to 347 grams of carbohydrate can be converted into more than 9 foods or 463 grams of rice (nearly 5 bowls of cooked rice). Many women with light physical activity can't eat a small bowl of rice at every meal, and even 50% of their carbohydrate ratio is not enough.
The Report on Nutrition and Chronic Diseases in China (2015) (hereinafter referred to as the "Slow Disease Report") shows that the average dietary carbohydrate energy ratio of Chinese residents in 2012 was 55.0%, the protein was 12.1% and the fat was 32.9%. Overall mortality, mortality from non-cardiovascular diseases and stroke risk were all low, according to the study. In other words, the carbohydrate ratio of the majority of our residents cannot be called "high" but "appropriate", according to this article. The study did not find any benefit in reducing carbohydrate supply to less than 40 percent over the long term, and did not support "eating less or even eating staples."
from 1992 to 2012, the carbohydrate energy ratio of our residents has been on a downward trend, but at a reasonable level. It is worth noting that some young people in order to lose weight basically do not eat or eat very few staple foods, and some professionals are busy paying to ignore staple foods, these are not in line with the balanced diet model. The Dietary Guidelines for Chinese Residents (2016) (hereinafter referred to as the Dietary Guidelines) recommend a carbohydrate energy ratio of 50% to 65%, daily intake of cereals and potatoes 250 to 400 grams, including whole grains and mixed beans 50 to 150 grams, potatoes 50 to 100 grams.
, a fellow at the American Medical School and head of Harvard's Department of Nutrition, said the study was problematic in mixing all carbohydrates. Carbohydrate-rich foods include both white rice, white noodles and added sugars, as well as whole grains, potatoes, and legumes, which are harmful to the body, and increased intake, which can reduce mortality. Current U.S. dietary guidelines emphasize that the latter should be used instead of the former.
Focus II
Study: Eating less fat is not good
Experts: Chinese fat intake needs to be controlled
This study found that if the dietary fat supply ratio from low to high divided into 5 groups, of which fat supply than the lowest group (10.6%), total mortality, non-cardiovascular disease mortality, stroke risk is the highest; The findings lead to the idea that "eating less fat is bad."
" does not mean that the more fat you eat, the better. Fan Zhihong said that at present, the average dietary fat energy ratio of China's residents as high as 32.9%, of which urban residents as high as 36.1%, has exceeded the study fat energy ratio of the highest group. There is no evidence of any additional benefits from increased fat intake.
so-called 10.6% too low fat supply than how to eat? The conversion is equivalent to eating 21.2 grams of fat per day. Specifically, eat 1 or 2 pork chops (debony), 11.6 grams of fat, 1 egg, 4.8 grams of fat, 1 cup of milk (200 grams, 3.1 percent fat) and 6.2 grams of fat. Without eating a drop of fried vegetable oil, eating only these three foods has ingested 21.6 grams of fat. The average person has no need to worry about not eating enough fat, and certainly does not rule out that some people lack fat.
recent years, the importance of fat to the human body has been ignored, people seem to remember only "fat harmful", some people even go to extremes, to avoid. The human body can not be separated from fat, diet if long-term lack of fat, may cause fat-soluble vitamins and a variety of trace elements lack, leading to human dysfunction. The more fat, the better. In this study, "fat more good" is based on the total calories of the day unchanged under the condition of the results. But because the fat taste fragrance, low satiety, into the dishes and food does not increase the volume, eat more fat, people often do not reduce the staple food as a remedy, easily increase the total calories, increase the risk of obesity. Dietary guidelines recommend that fat energy ratio of 20% to 30% is appropriate.
to be reminded that cooking oil is an important source of dietary fat, fat content of nearly 100%, especially to limit. In 2012, the average daily intake of edible oil per person in China was 42.1 grams, and only 45% of adult residents' intake met the recommended daily intake of 30 grams, and about 26% consumed more than 50 grams per day. It is recommended that the daily cooking oil consumption is controlled at 25 to 30 grams, in order to facilitate the quantitative use of oil, it is best to pour oil into the gyrations, steaming, cooking, stewing, stewing and other cooking methods to reduce the amount of oil used, fried food although the taste is good, scented enough, but to eat less.
Focus III
Research: Protein can not be too little
Experts: The elderly should pay special attention to
protein is very important to the human body, growth and development, wound repair, immune antibodies, etc. are inseparable from it. The study found that the lowest group (10.8%) had the highest overall mortality rate and the highest mortality rate for non-cardiovascular diseases, and that the risk of protein supply ratio was relatively low between 15% and 20%.
, said the findings suggest it's important to eat enough protein. Fish, meat, eggs, milk, soy products are high-quality sources of protein, but some elderly people in life repeatedly in order to pursue "diet light", adhere to white porridge on small dishes, noodles with salty brine eating method, the result of poor physical fitness, high body fat, blood sugar, blood pressure, blood lipids are not down. For people who have more physical activity or love fitness, eating like this every day is not conducive to a long and healthy life.
dietary guidelines recommend a protein-to-energy ratio of 10% to 20%, moderate intake of fish, poultry, eggs and lean meat, eat fish 280 to 525 grams per week, livestock meat 280 to 525 grams, eggs 280 to 350 grams, the average daily intake of 120 to 200 grams;
Focus IV
Study: Eating fruits and vegetables raw reduces the risk of death
Experts: People who don't like to eat vegetables are "big problems
Another study by the same team found that eating three to four servings of fruits and vegetables and beans a day reduced the risk of non-cardiovascular death by 23% and the risk of death by 2% compared to people who ate less than one serving a day (125 grams of fruits and vegetables or 150 grams of cooked beans). The results may not seem fresh, but it's worth noting that people who ate one to two servings of raw vegetables a day had a 19 percent lower risk of death than those who ate less than one serving a month.
is a "big problem" problem because of the insufficient intake of fruits, vegetables and beans among the residents of our country. According to the report, in 2012, the average resident of China consumed 269.4 grams of fresh vegetables, 40.7 grams of fruit, 10.9 grams of soybeans and products per person per day, a total of 321 grams. Dietary guidelines recommend that each person daily intake of vegetables 300 to 500 grams, fruit 200 to 350 grams, soy and nuts 25 to 35 grams, with the minimum recommended amount of 525 grams, there is still a large gap. Therefore, experts suggest that Chinese people should pay special attention to increase the consumption of these three types of food. It's not hard to eat enough 300 to 500 grams of vegetables. For example, 1 small bowl of spinach about 150 grams, 1 bowl of cabbage about 150 grams, and then add half a bowl of fried green pepper carrot silk, raw eat 1 tomato, the total amount of more than 500 grams, divided into three meals to eat, not too much. 350 grams of fruit is also easy to do, such as 1 kiwi plus 1 apple, 1 large orange plus 1 pear, 1 umbilical orange plus a small box of blueberries, just right.
to eating vegetables raw, Fan Zhihong said, the study alone can not conclude that "vegetables must be eaten raw." Eating vegetables raw has a greater sense of satiety, better preserved nutrients, and better promotes intestinal movement. But for everyone, the exact proportion of raw food depends on their chewing function, digestive function and physical resistance.
fact, cooked vegetables are an advantage of traditional Chinese diets, and although cooking may lose some nutrients, it can increase total intake and absorption of some nutrients. In addition, the variety of vegetables that can be eaten raw is very limited, such as tomatoes, radish, lettuce, bell peppers, cucumbers and so on. Some vegetables are nutritious, but do not have raw food conditions, such as orchids, spinach, beans, pumpkins, mushrooms and so on. Encourage everyone to eat vegetables when a variety of varieties, raw and cooked, less oil salt, do not just stare at a small number of raw varieties.
: The publication of the two papers was accompanied by a review in The Lancet. The study "challenges the definition of a healthy diet, but the key issues are not addressed," the authors said. Epidemiologists, for example, point out that this article does not deal well with confuse factors.
Because of the large differences in the economic situation, eating habits, lifestyle, burden of disease, etc. of the respondents in each country, in statistical analysis, the situation of each country should generally be considered separately, and the background conditions are not very different in order to combine the data, otherwise it is easy to get the illusion. Fan Zhihong, for example, when investigating the health effects of air quality, such as Beijing, a city with high air pollution but good medical conditions, high life expectancy and Lhasa, a city with low pollution but low life expectancy, said that although air pollution is small and healthy, it is likely that due to a variety of other factors, it is likely to result in "pollution is good for longevity" absurd results. The findings may not confirm causation.
, a tenured professor of medicine and epidemiology at Brown University in the United States, said the study had much to do with its publication in The Lancet. However, whether the magazine is famous or not, it's just an article. Papers published in medical journals are mainly for professionals to read, need expertise to explain clearly, non-professionals and the media should not over-interpret, according to their own purposes to guide the reader. Research that has implications for clinical and public health needs to be based on evidence-based medicine, consistency and repeatability, and this study is clearly not rigorous enough.
In order to be positive, the Chinese Nutrition Society specifically called for: Mo to take the new research as a new conclusion, scientific truth needs to be supported by multiple studies and evidence; Yan (Reporter Gao Yang)