伊朗德黑兰医科大学Omid Sadeghi团队研究了α-亚麻酸的膳食摄入和生物标志物与全因、心血管和癌症死亡率的风险。相关论文于2021年10月14日发表在《英国医学杂志》上。

为了研究α-亚麻酸（ALA）的饮食摄入和组织生物标志物与全因、心血管疾病（CVD）和癌症死亡率之间的关系，研究组在PubMed、Scopus、科学引文索引等大型数据库中检索截至2021年4月30日关于全因、CVD和癌症死亡风险估计的前瞻性队列研究的文献，并进行系统回顾和荟萃分析。使用随机效应和固定效应模型计算ALA摄入量最高和最低类别的相对风险和95%置信区间。进行线性和非线性剂量反应分析，以评估ALA摄入量与死亡率之间的剂量反应相关性。

该研究共纳入41篇前瞻性队列研究，涉及1197564名参与者。在2-32年的随访期间，198 113例全因死亡，62773例CVD死亡，65954例癌症死亡。与低摄入ALA相比，高摄入ALA与较低的全因、CVD和冠心病（CHD）死亡风险显著相关，但癌症死亡率略高。

在剂量反应分析中，每天增加1g ALA摄入量（相当于一汤匙菜籽油或0.5盎司核桃仁）可降低5%的全因死亡和CVD死亡风险。与最低组织水平ALA相比，最高组织水平ALA的综合相对风险与全因死亡率呈显著负相关。此外，根据剂量-反应分析，ALA血药浓度每增加1个标准差，CHD死亡率就会降低。

研究结果表明，饮食中摄入ALA与全因、CVD和CHD的死亡率降低相关，与癌症死亡率略微升高相关，而血液中ALA水平升高仅与全因和CHD死亡率降低相关。

附：英文原文

Title: Dietary intake and biomarkers of alpha linolenic acid and risk of all cause, cardiovascular, and cancer mortality: systematic review and dose-response meta-analysis of cohort studies

Author: Sina Naghshi, Dagfinn Aune, Joseph Beyene, Sara Mobarak, Masoomeh Asadi, Omid Sadeghi

Issue&Volume: 2021/10/14

Abstract:

Objective To examine the associations between dietary intake and tissue biomarkers of alpha linolenic acid (ALA) and risk of mortality from all causes, cardiovascular disease (CVD), and cancer.

Design Systematic review and meta-analysis of prospective cohort studies.

Data sources PubMed, Scopus, ISI Web of Science, and Google Scholar to 30 April 2021.

Study selection Prospective cohort studies that reported the risk estimates for death from all causes, CVD, and cancer.

Data synthesis Summary relative risks and 95% confidence intervals were calculated for the highest versus lowest categories of ALA intake using random effects and fixed effects models. Linear and non-linear dose-response analyses were conducted to assess the dose-response associations between ALA intake and mortality.

Results 41 articles from prospective cohort studies were included in this systematic review and meta-analysis, totalling 1197564 participants. During follow-up ranging from two to 32 years, 198113 deaths from all causes, 62773 from CVD, and 65954 from cancer were recorded. High intake of ALA compared with low intake was significantly associated with a lower risk of deaths from all causes (pooled relative risk 0.90, 95% confidence interval 0.83 to 0.97, I2=77.8%, 15 studies), CVD (0.92, 0.86 to 0.99, I2=48.2%, n=16), and coronary heart disease (CHD) (0.89, 0.81 to 0.97, I2=5.6%, n=9), and a slightly higher risk of cancer mortality (1.06, 1.02 to 1.11, I2=3.8%, n=10). In the dose-response analysis, a 1 g/day increase in ALA intake (equivalent to one tablespoon of canola oil or 0.5 ounces of walnut) was associated with a 5% lower risk of all cause (0.95, 0.91 to 0.99, I2=76.2%, n=12) and CVD mortality (0.95, 0.91 to 0.98, I2=30.7%, n=14). The pooled relative risks for the highest compared with lowest tissue levels of ALA indicated a significant inverse association with all cause mortality (0.95, 0.90 to 0.99, I2=8.2%, n=26). Also, based on the dose-response analysis, each 1 standard deviation increment in blood concentrations of ALA was associated with a lower risk of CHD mortality (0.92, 0.86 to 0.98, I2=37.1%, n=14).

Conclusions The findings show that dietary ALA intake is associated with a reduced risk of mortality from all causes, CVD, and CHD, and a slightly higher risk of cancer mortality, whereas higher blood levels of ALA are associated with a reduced risk of all cause and CHD mortality only.

DOI: 10.1136/bmj.n2213

Source: https://www.bmj.com/content/375/bmj.n2213