News Release 8-Jul-2020

Findings further support advice to eat more of these foods to prevent disease

BMJ

Higher consumption of fruit, vegetables and whole grain foods are associated with a lower risk of developing type 2 diabetes, according to two studies published by The BMJ today.

The findings suggest that even a modest increase in consumption of these foods as part of a healthy diet could help prevent type 2 diabetes.

In the first study, a team of European researchers examined the association between blood levels of vitamin C and carotenoids (pigments found in colourful fruits and vegetables) with risk of developing type 2 diabetes.

Vitamin C and carotenoid levels are more reliable indicators of fruit and vegetable intake than using dietary questionnaires.

Their findings are based on 9,754 adults who developed new-onset type 2 diabetes and a comparison group of 13,662 adults who remained free of diabetes during follow-up from among 340,234 participants who were taking part in the European Prospective Investigation into Cancer and Nutrition (EPIC)-InterAct study in eight European countries.

After adjusting for lifestyle, social and dietary risk factors for diabetes, higher blood levels of each of vitamin C and carotenoids and their sum when combined into a “composite biomarker score” were associated with a lower risk of developing type 2 diabetes.

Compared with people who had the lowest composite biomarker score, the risk in people whose biomarker score was in the top 20% of the population was 50% lower. The risk in those with biomarker scores between these two extremes was intermediate.

The researchers calculate that every 66 grams per day increase in total fruit and vegetable intake was associated with a 25% lower risk of developing type 2 diabetes.

In the second study, researchers in the United States examined associations between total and individual whole grain food intake and type 2 diabetes.

Their findings are based on 158,259 women and 36,525 men who were free from diabetes, heart disease and cancer and were taking part in the Nurses’ Health Study, Nurses’ Health Study II, and Health Professionals Follow-Up Study.

After adjusting for lifestyle and dietary risk factors for diabetes, participants in the highest category for total whole grain consumption had a 29% lower rate of type 2 diabetes compared with those in the lowest category.

For individual whole grain foods, the researchers found that consuming one or more servings a day of whole grain cold breakfast cereal or dark bread was associated with a lower risk of type 2 diabetes (19% and 21% respectively) compared with consuming less than one serving a month.

For other individual whole grains with lower average intake levels, consumption of two or more servings a week compared with less than one serving a month was associated with a 21% lower risk for oatmeal, a 15% lower risk for added bran, and a 12% lower risk for brown rice and wheat germ.

These reductions in risk seemed to plateau at around two servings a day for total whole grain intake, and at around half a serving a day for whole grain cold breakfast cereal and dark bread.

Both studies are observational so can’t establish cause, and there’s a possibility that some of the results may be due to unmeasured (confounding) factors. However, both studies took account of several well known lifestyle risk factors and markers of dietary quality, and the findings back up other research linking a healthy diet with better health.

As such, both research teams say their findings provide further support for current recommendations to increase fruit, vegetable and whole grain consumption as part of a healthy diet to prevent type 2 diabetes.

And for fruit and vegetables, the findings also suggest that consumption of even a moderately increased amount among populations who typically consume low levels could help to prevent type 2 diabetes.

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Peer reviewed? Yes
Evidence type: Observational
Subjects: European and US adults

3907/5000研究結果進一步支持建議多吃這些食物以預防疾病

英國醫學雜誌

BMJ今天發表的兩項研究表明，水果，蔬菜和全穀類食品的高消費與患2型糖尿病的風險降低有關。

研究結果表明，即使這些食物作為健康飲食的一部分適度增加，也可以幫助預防2型糖尿病。

在第一項研究中，一組歐洲研究人員研究了血液中維生素C和類胡蘿蔔素（在五顏六色的水果和蔬菜中發現的色素）之間的關聯，類胡蘿蔔素易患2型糖尿病。

與使用飲食問卷相比，維生素C和類胡蘿蔔素水平是更可靠的水果和蔬菜攝入量指標。

他們的發現是基於參與歐洲前瞻性癌症和營養調查（EPIC）的340,234名參與者中的9,754名發展為新發2型糖尿病的成年人和13662名在隨訪期間未患糖尿病的成年人的比較組中的）-InterAct在八個歐洲國家的研究。

在調整生活方式後，糖尿病的社會和飲食風險因素，維生素C和類胡蘿蔔素各自的較高血液水平以及它們的總和（與“綜合生物標誌物得分”相結合）與罹患2型糖尿病的風險較低相關。

與生物標記綜合得分最低的人群相比，生物標記得分最高的20％人群的風險降低了50％。生物標誌物得分介於這兩個極端之間的風險是中等的。

研究人員計算出，每天水果和蔬菜攝入量每增加66克，患2型糖尿病的風險降低25％。

在第二項研究中，美國的研究人員檢查了全穀物食物攝入總量和個體與2型糖尿病之間的關聯。

他們的發現基於158259名女性和36525名男性，他們沒有糖尿病，心髒病和癌症，並且參加了護士健康研究，護士健康研究II和健康專業人員隨訪研究。

在調整了生活方式和糖尿病的飲食風險因素後，總穀物消費量最高的類別的2型糖尿病患病率比最低類別的參與者低29％。

對於單個全穀物食品，研究人員發現，一天食用一份或多份全穀物冷早餐麥片或黑麵包與2型糖尿病的發生風險相比較低（分別為19％和21％），而少於一次服務一個月。

對於其他平均攝入量較低的單獨全穀物，每週食用兩份或以上與每月少於一份相比，燕麥片的風險降低了21％，麩皮的風險降低了15％，而穀物的攝入量降低了12糙米和小麥胚芽的風險降低％。

這些風險降低似乎使全穀物的總攝入量每天減少約兩份，而全穀物的冷早餐穀物和黑麵包則減少到每天約半份。

兩項研究都是觀察性的，因此無法確定原因，並且有可能某些結果可能歸因於無法衡量的（混雜）因素。但是，兩項研究均考慮了幾種眾所周知的生活方式風險因素和飲食質量標誌物，這些發現支持了其他將健康飲食與更好的健康聯繫起來的研究。

因此，兩個研究小組都說，他們的發現為當前建議增加水果，蔬菜和全穀物的消費量提供了進一步的支持，以作為預防2型糖尿病的健康飲食的一部分。

對於水果和蔬菜，研究結果還表明，在通常攝入量低的人群中，即使攝入適度增加的量也可以幫助預防2型糖尿病。