編者按2020年6月，美國鹽城湖山間醫學中心的Benjamin Horne教授在JAMA雜誌發表了一篇觀點文章，闡述了間歇性禁食對2型糖尿病患者的健康影響以及其安全性。JAMA雜誌的主編Howard Bauchner博士就該話題與Benjamin Horne教授進行了討論。接下來的幾期，我們將圍繞間歇性禁食這一話題展開討論。

Howard Bauchner博士（左一），JAMA雜誌主編；

Benjamin Horne教授（右一），美國鹽城湖山間醫學中心

中英文字幕

Howard Bauchner：我是Howard Bauchner，本期我將和Benjamin Horne對話。Ben為JAMA雜誌撰寫了一篇題為《間歇性禁食對2型糖尿病患者健康影響和安全性的證據有限》的觀點文章。Ben是美國鹽城湖山間醫學中心的心血管和遺傳流行病學主任，他從1996年開始就在那裡工作。他同時還是斯坦福大學心血管醫學部的臨床副教授。歡迎Ben。

This is Howard Bauchner, and I'll be talking with Benjamin Horne. Ben has authored a viewpoint for JAMA that's entitled “Limited evidence to the health effects and safety of intermittent fasting among patients with type 2 diabetes mellitus”. Ben is the director of cardiovascular and genetic epidemiology at Intermountain, where he's been since 1996. And he holds an appointment as a clinical associate professor in the division of cardiovascular medicine at Stanford University. Welcome Ben.

Thank you. Thank you for having me.

Oh, I'm delighted. So, Ben, before we start, could you say something about your two co-authors?

Benjamin Horne：我的合著者Martin Grajower，是紐約阿爾伯特·愛因斯坦醫學院的內分泌學家，他一直在治療患有糖尿病但同時也渴望進行間歇性禁食或出於宗教目的禁食的患者。所以他深耕這個領域。Jeffrey Anderson博士是一位心臟病學專家，我和他在山間醫學中心做了24年同事。多年來我們倆共同撰寫了大量文章，後來他成了我的導師，他在臨床心臟病學方面有很好的見解。

My co-authors are Martin Grajower who is a endocrinologist at Albert Einstein College of medicine in New York and he has been treating people who both have diabetes, of course, but also are anxious to engage in intermittent fasting or fasting for religious purposes. And so he's had an interest in this field. Dr Jeffrey Anderson is a cardiologist that I've been colleagues with him in Inner mountain, for about 24 years now and have been able to be co-authors with him on myriad of articles over the years. But then one of my mentors, and has great insights into the clinical cardiology side.

Well certainly, the relationship between intermittent fasting and type 2 diabetes calorie restriction has grown in popularity over the last few years. But before we discussing detail the data around the relationship, could we first start by defining what intermittent fasting is?

Benjamin Horne：它有各種各樣的定義，取決於您想要如何定義它。實際上，最具宗教意義的禁食可以歸屬於間歇性禁食。但當間歇性禁食被用作一個術語時，它通常與為健康目的而進行的間歇效能量限制有關。有很多種流行的禁食方式，不同的禁食方式，人們會停止攝入熱量一天，一週兩次，甚至隔日禁食。還有另一種說法，即時間限制性進食，每天堅持16小時內不吃東西，在8小時內只攝入需要消耗的熱量。還有很多其他的禁食方式，我們目前正在研究。在我們的一些臨床研究中，我們要求人們每週禁食一天，即每週禁食24小時。還有各種各樣的其他方式，比如少量的熱量攝入，在齋戒日的中途，小加餐一頓，還有一些其他的方式。我們一直在進行禁食期間只喝水的研究，即在24小時內不攝入熱量。

There are variety of definitions, and depending on how you want to define it. The finding intermittent, actually, a most religious fasting could fall into that, but usually when intermittent fasting is used as a term, it relates to engaging in intermittent energy restriction for health purposes. And there are a variety of popular ways of doing that, different regiments where people will cease their caloric intake for a period of about 1 day, twice per week, or even every other day, which they call alternate day fasting. And then there's another version, another regiment, which is time restricted feeding, where every day people will not eat for a period of about 16 hours and then only eats whatever calories they do consume during an eight-hour period. There are variety of others we actually are looking at a regimen. And some of our trials, where we're asking people to fast for just 1 day per week, so a-24-hour period just once per week. There are variety of others, some of them include a small caloric intake, a small meal about half way through the fasting day, and others are not. We have been studying water, only fasting, so no caloric intake during a-24-hour period.

Howard Bauchner：當人們談到間歇性禁食時，是否意味著他們在你剛才提到的時間段內也不喝水，他們能喝水嗎?

When people talk about intermittent fasting, does that imply that they don't drink during that time period that you just mentioned, can they drink?

Benjamin Horne：通常間歇性禁食期間他們會喝一些飲料，有些會喝果汁或骨湯，有些只喝白開水。但通常需要攝入一些液體。

Usually for intermittent fasting, and they will be drinking, and some regiments include things like juices or bone broth others, it's plain water only. But usually, it includes consuming some kind of fluid.

Howard Bauchner：那麼，禁食時，生理學方面會發生什麼?

Now, when you do fast, what happens physiologically?

Benjamin Horne：這是個好問題。有各種各樣的研究，主要集中在動物實驗，試圖解決兩種通常提及的主要機制，包括酮糖。由於禁食的營養壓力，身體從利用葡萄糖作為其主要的能量來源轉為使用酮類和脂肪酸成為燃料。禁食的作用是把脂肪酸從儲存區域和脂肪細胞中抽提出來。反覆的禁食會導致胰島素抵抗改善。另一種是自噬，由於營養壓力，機體也會進行一些細胞清理，分解不必要的或功能不正常的細胞器或分子。這其中可能包括很多環節，其中一個很有前景。研究發現，功能不理想的線粒體被降解之後，可能引起線粒體的生髮。所以新的線粒體在我們體內產生，此外還有很多其他的機制。我們一年前發表的一個機制和微生物組有關，間歇性禁食可使體內氧化三甲胺減少，而氧化三甲胺與心血管疾病風險有關。還有很多其他途徑正在研究中，它們可能對心血管、代謝風險和認知功能有影響。

That's a good question. There are a variety of studies, primarily in animals that have attempted to address that the two primary mechanisms that are commonly referred to, include ketoses. Where the body, due to the nutritional stress of fasting, the body switches from utilizing glucose as its primary source of energy to using ketones and fatty acids for fuel. And what that does is it pulls those fatty acids out of, presumably, storage areas, fat cells. And over repeated episodes of fasting will cause the insulin resistance to go down. Another is autophagy, where the body also, due to that, nutritional stress engages in some cellular cleanup, disassembles unnecessary or dysfunctional organelles or molecules, and that might include a variety of things. One that's showing a lot of promise. In researches that less than optimally functional mitochondria are degraded, and it might induce mitochondrial genesis. So that new mitochondria are created inside ourselves and a variety of other mechanisms, one that we've published on a year ago link to the microbiome, where we showed that trimethylamine-N-oxide was reduced by intermittent fasting, of TMAO, which is linked to cardiac risk. And they're variety of other pathways that are being examined that may have an effect on cardiac risk, on metabolic risk and on our cognitive function.

相關單詞學習：

intermittent fasting

間歇性禁食

endocrinologist

內分泌學家

religious purposes

出於宗教目的

ketoses /ki'təusi:z/

酮糖（ketosis的複數）

ketones

酮類（ketone的複數）

autophagy /ɔːˈtɑːfədʒi/

自噬

mitochondria /ˌmaɪto'kɑndrɪr/

n. 線粒體（mitochondrion /ˌmaɪtoʊˈkɑːndriən/ 的複數）

microbiome

微生物組

trimethylamine-N-oxide =TMAO

氧化三甲胺