So I recently turned 30 and I decided that I wanna take my health a lot more seriously than I have done in the past.

我最近剛滿 30 歲，我決定要比過去更重視自己的健康。

And I've been trying to figure out what are genuinely the scientific evidence-based habits that I can add to my life that will help me be healthier.

我一直在試圖找出哪些真正有科學依據的生活習慣可以讓我的生活更健康。

Now in this video, we're gonna be talking about three specific health habits.

在本視頻中，我們將討論三個具體的健康習慣。

We're gonna be talking about should you be getting 10,000 steps a day?

我們要討論的是，你應該每天走一萬步嗎？

We're gonna talk about how much sun exposure should you get and should you actually be going out in the sun first thing in the morning?

我們要討論的是你應該晒多少太陽，以及你是否真的應該一早出門晒太陽？

Thirdly, we're gonna talk about how much water should you actually be drinking and should you aim for two and a half liters per day?

第三，我們要談談你究竟應該喝多少水，是否應該以每天兩升半為目標？

I was kind of surprised doing the research for this video because it seems like a lot of the recommendations we get aren't really that evidence-based.

在為這段視頻做研究時，我感到有點驚訝，因為我們得到的很多建議似乎並不是真的那麼有依據。

Oh, and by the way, if you're new to the channel, hi, my name is Ali.

對了，如果你是頻道的新成員，你好，我叫阿里。

I'm a doctor turned entrepreneur and YouTuber and author of the book, Feel Good Productivity, which is about how to be more productive in a way that feels good.

我是一名醫生，後來成為了一名企業家、YouTuber 和《感覺良好的生產力》一書的作者，這本書講述瞭如何以一種感覺良好的方式提高生產力。

And so in this video, I'm excited to dive into some of the scientific research around these three fairly simple but important health habits.

是以，在這段視頻中，我很高興能圍繞這三個相當簡單但卻非常重要的健康習慣，深入探討一些科學研究。

So let's get into it.

那我們就開始吧。

All right, so back in 1964, before the Tokyo Olympic Games, there was a marketing campaign that was used to promote walking 10,000 steps a day.

好了，早在 1964 年東京奧運會之前，就有一場營銷活動，用來宣傳每天步行一萬步。

And this number was chosen because the Japanese character for 10,000 looks like a person walking, apparently.

之所以選擇這個數字，是因為 "10,000 "的日文字形顯然像一個人在走路。

And during this campaign, they were promoting this device called the manpoukei.

在這場運動中，他們正在推廣一種叫做 manpoukei 的裝置。

And in Japanese, manpoukei literally means 10,000 steps meter, which counts the number of steps you've taken.

在日語中，manpoukei 的字面意思是萬步計，它可以計算你走過的步數。

So this number was chosen pretty randomly for the campaign, but it's become mainstream all over the world.

是以，這個數字是隨機選擇的，但它已成為全世界的主流。

And now it's like the number that everyone talks about when it comes to walking.

現在，一提到走路，大家都會談論這個數字。

But does the science actually support this?

但科學是否真的支持這一點呢？

Should we actually be walking 10,000 steps a day?

我們真的應該每天走一萬步嗎？

Now, this is something I've been really keen to find out because 10,000 steps a day is actually quite a lot and left to my own devices,

現在，我非常想知道這一點，因為每天走 10,000 步實際上已經很多了，如果由我自己來決定的話、

I only get maybe 4,000 or 5,000 steps a day.

我每天大概只能走 4000 或 5000 步。

So I've been trying to figure out should I actually be walking more?

所以我一直在想，我是否應該多走一些路？

Is it genuinely good for my health?

它真的對我的健康有益嗎？

Now, you might not know this, but 10,000 steps is about five miles or eight kilometres with a little bit of variation depending on the individual.

你可能不知道，一萬步約等於五英里或八公里，因人而異。

And it roughly takes one hour and 40 minutes to walk 10,000 steps.

而走 1 萬步大概需要 1 小時 40 分鐘。

Conveniently, this roughly translates to 10 minutes per 1,000 steps.

方便地說，這大致相當於每走 1000 步需要 10 分鐘。

This was new to me.

這對我來說很新鮮。

I had no idea until we were doing research for this video.

直到我們為這段視頻做研究時，我才知道。

It's like, oh, every 1,000 steps you do, you need to walk for about 10 minutes.

這就像，哦，你每走 1000 步，就需要走 10 分鐘左右。

But 10,000 steps is 100 minutes.

但 1 萬步就是 100 分鐘。

And so should we really be spending 100 minutes every single day just walking?

那麼，我們真的應該每天花 100 分鐘散步嗎？

To answer that question, let's look at what some of the data says.

要回答這個問題，讓我們看看一些數據是怎麼說的。

Now, meta-analyses are these big studies that take data from lots of other research papers and bring them together, which is kind of cool.

現在，薈萃分析是一種大型研究，它從大量其他研究論文中提取數據，並將其整合在一起，這有點酷。

And this meta-analysis from 2022 looked at 15 different studies to see how daily step count was associated with the risk of dying from any cause.

2022 年的這項薈萃分析研究了 15 項不同的研究，以瞭解每日步數與任何原因導致的死亡風險之間的關係。

And in science, this is what we call all-cause mortality.

在科學上，這就是我們所說的全因死亡率。

This graph shows how your risk of death changes with the more steps you take each day.

這張圖顯示了您的死亡風險是如何隨著每天走的步數增加而變化的。

This is what it looks like for people younger than 60, and this is what it looks like for people older than 60.

60 歲以下的人是這個樣子，60 歲以上的人是這個樣子。

So if you're younger than 60 years old, which you probably are if you're watching this channel, the optimal number of steps to take is around 8,000 to 10,000.

是以，如果您的年齡小於 60 歲（如果您正在收看本頻道，您可能就是 60 歲），最佳步數約為 8,000 至 10,000 步。

And for people older than 60, you actually lower your risk of death by about 50% by only walking about 6,000 steps per day.

而對於 60 歲以上的老人來說，每天只需步行約 6000 步，就能將死亡風險降低約 50%。

Now, because both of these lines are really steep at the start, this tells us that increasing our daily step count is really good if you are currently pretty inactive and you don't move around a lot.

現在，由於這兩條線在開始時都非常陡峭，這就告訴我們，如果你目前非常不活躍，也不經常走動，那麼增加每天的步數真的很好。

And then over 10,000 steps per day, you can start to see that the graph sort of starts to level out.

然後，每天走 1 萬步以上，你就會發現圖表開始趨於平緩。

But to be honest, this is probably because there's not actually enough studies that specifically look at people who actually do walk over 10,000 steps per day.

但老實說，這可能是因為沒有足夠的研究專門研究那些每天步行超過 10,000 步的人。

So the data in this range is a little bit more unreliable, and we don't actually know quite yet if your risk of dying keeps on decreasing if you just take more and more and more steps.

是以，這個範圍內的數據有點不可靠，我們實際上還不知道，如果你走的步數越來越多，死亡的風險是否會持續降低。

Now, this graph is for all-cause mortality, but interestingly, we see exactly the same pattern when it comes to your risk of cancer and dementia and heart disease.

現在，這張圖顯示的是全因死亡率，但有趣的是，在癌症、痴呆症和心臟病風險方面，我們看到了完全相同的模式。

In this study, for example, researchers measured the number of steps taken per day by around 80,000 adults in the UK around the age of 61 to see how this changed their risk of getting dementia around seven years later.

例如，在這項研究中，研究人員測量了英國約 8 萬名 61 歲左右的成年人每天走的步數，以瞭解這對他們七年後患痴呆症的風險有何影響。

And as we can see here, the total number of steps per day that showed the greatest reduction in risk of dementia was just under 10,000, this magic number again.

正如我們在這裡所看到的，每天減少痴呆症風險最大的總步數略低於 10,000 步，這又是一個神奇的數字。

We can see a similar sort of pattern for cancer, as in this graph.

在癌症方面，我們也可以看到類似的模式，如圖所示。

And again, here you can see around 10,000 is when things start to get interesting.

同樣，在這裡你可以看到，在 10,000 點左右，情況開始變得有趣起來。

And we also see pretty much an identical pattern when it comes to heart disease.

在心臟病方面，我們也看到了幾乎相同的模式。

And again, if you zoom into the graph, you see that this 10,000 number shows up again and again.

同樣，如果放大圖表，你會發現這個 10,000 的數字一再出現。

Now, if we look at all-cause mortality again, and we separate it out into people who sit for more than 10 hours a day, i.e. me, and people who sit less than 10 hours a day, if you sit a lot, then actually the benefit of walking those 10,000 steps is greater than people that don't sit a lot.

現在，如果我們再看一下全因死亡率，並將其分為每天坐10小時以上的人，也就是我，和每天坐10小時以下的人，如果你經常坐著，那麼實際上走1萬步的益處要大於不經常坐著的人。

And so what this data shows is that it looks like walking seems to offset the negative health outcomes associated with sitting at a desk all day.

是以，這些數據表明，步行似乎可以抵消整天坐在辦公桌前對健康造成的負面影響。

Okay, so let's talk about the key takeaways from all these studies.

好了，讓我們來談談這些研究的主要啟示。

So firstly, any amount of walking is good for you, and you don't necessarily need to hit 10,000 steps to start seeing the benefits from walking.

是以，首先，任何數量的步行都對你有益，你不一定要走到一萬步才能開始看到步行帶來的好處。

But in general, the more walking you do, the better.

但總的來說，走得越多越好。

And also the faster you walk too, the better.

而且走得越快越好。

There was a bunch of studies about this, they were too long to include in this video.

有關這方面的研究很多，但篇幅太長，無法收錄在本視頻中。

But if you walk at a brisk pace, you're more likely to get benefits than if you walk super, super slowly.

但是，如果你以輕快的步伐行走，就比你走得超級超級慢更有可能獲得益處。

Also, if you walk faster, it takes less time to get in your 10,000 steps.

此外，如果你走得更快，就能用更少的時間走完一萬步。

Now, a great target to aim for for most people is around 6,000 to 8,000 steps per day, because beyond that, the benefits do start to diminish.

現在，大多數人的目標是每天走 6000 到 8000 步左右，因為超過這個目標，好處就會開始減少。

And if you remember that 1,000 steps is equivalent to about 10 minutes of walking, then this goal actually seems pretty realistic for a lot of us.

如果你記得 1,000 步相當於步行 10 分鐘左右，那麼這個目標對我們很多人來說其實是非常現實的。

This would mean that if you walk, for example, 30 minutes total in your commute to get the train or the bus to work, whatever the thing is, that would be 3,000 steps.

這意味著，如果您在上下班途中步行 30 分鐘，搭乘火車或公共汽車去上班，不管是什麼交通工具，這都將是 3000 步。

And then you only really need another half an hour walk, which you can take during a lunch break or any other time, to be hitting that target of 6,000.

然後，你只需要再步行半小時，可以在午休或其他時間進行，就能達到 6000 步的目標。

So what I'm personally taking away from this is that I'm gonna aim to start off my day with a half an hour walk around the local park with a little coffee, and that will be my first 3,000 steps.

是以，我個人從這件事中得到的啟示是，我每天的目標是在當地公園散步半小時，再喝一點咖啡，這將是我的第一個 3000 步。

And then I'm also gonna try my best to, like, you know, when I have to get to a restaurant that might be half an hour away, aiming to walk there for 3,000 steps rather than getting an Uber or getting the Tube.

然後，我也會盡我所能，比如，你知道，當我要去一家可能要半小時車程的餐館時，我的目標是步行 3000 步，而不是打 Uber 或坐地鐵。

Walking also has a bunch of benefits to creativity, which we're not talking about in this video, but, you know, this is why I find whenever I'm kind of feeling blocked on writing or anything I'm working on, actually just going for a walk really helps clear my mind, and it means that I'm more creative, but I also get the steps in, which is always a good thing.

散步對創造力也有很多好處，我們在這個視頻中沒有談到，但是，你知道，這就是為什麼我發現每當我在寫作或任何事情上感到受阻時，實際上只是去散步真的有助於理清我的思緒，這意味著我更有創造力，而且我還能邁開步子，這總是一件好事。

And as of last week, when we did the research for this video,

截至上週，當我們為這段視頻做研究時、

I've decided to add in my daily walk as part of my ideal week.

我決定把每天散步作為理想周的一部分。

If you haven't yet come across my ideal week method for managing your time, there'll be a completely free template linked down in the video description, so you can check that out.

如果你還沒有接觸過我的理想周時間管理法，視頻描述中會有一個完全免費的模板鏈接，你可以去看看。

It's one of the time management techniques that has most impacted my life.

這是對我的生活影響最大的時間管理技巧之一。

But of course, mental health is just as important as physical help, and one way to improve that is with therapy provided by BetterHelp, who are the paid partner of this video.

當然，心理健康與身體健康同樣重要，而改善心理健康的方法之一就是接受 BetterHelp 提供的治療，BetterHelp 是本視頻的付費合作伙伴。

BetterHelp is the world's largest therapy service, and it's 100% online.

BetterHelp 是全球最大的心理治療服務機構，100% 在線服務。

With BetterHelp, you can tap into a network of over 30,000 credentialed and experienced therapists who can help you with a wide range of issues.

通過 BetterHelp，您可以利用由 30,000 多名經驗豐富的資深治療師組成的網絡，他們可以幫助您解決各種問題。

It's a platform that makes finding a therapist easy because it's online and it's remote, and by filling out a few questions,

這是一個可以輕鬆找到治療師的平臺，因為它是在線的，而且是遠程的，只需填寫幾個問題即可、

BetterHelp can match you to a credentialed therapist very quickly.

BetterHelp 可以快速為您匹配有資質的治療師。

Then you can talk to your therapist however you feel comfortable, whether it's via message or chat or phone or video call.

然後，您就可以通過資訊、哈拉、電話或視頻通話等方式，與您的治療師進行交談，無論您感覺如何。

Regardless of whether you have a clinical mental health issue like depression or anxiety, or if you're just a human who lives in this world who's going through a hard time, therapy can give you the tools to approach your life in a very different way.

無論你是否有抑鬱或焦慮等臨床心理健康問題，或者你只是一個生活在這個世界上的人，正在經歷一段艱難的時光，治療都能為你提供工具，讓你以一種截然不同的方式對待生活。

You can message your therapist at any time and schedule live sessions whenever it's convenient for you.

您可以隨時給治療師留言，並在方便的時候安排實時治療。

And if your therapist isn't the right fit for any reason, you can switch to a new therapist at no additional charge.

如果您的治療師因任何原因不適合您，您可以免費更換新的治療師。

If any of that sounds good, then BetterHelp can connect you to a therapist who can support you all from the comfort of your own home.

如果這些聽起來都不錯，那麼 BetterHelp 可以幫您聯繫一位治療師，讓他在您舒適的家中為您提供支持。

Head over to betterhelp.com forward slash Ali Abdaal or enter my name Ali Abdaal during the signup process and enjoy a special discount on your first month.

前往 betterhelp.com 轉發斜槓 Ali Abdaal 或在註冊過程中輸入我的名字 Ali Abdaal，即可在第一個月享受特別折扣。

Anyway, thanks BetterHelp, and let's get back to the video.

總之，感謝 BetterHelp，讓我們回到視頻上來。

All right, now we come to health habit number two, which is sun exposure.

好了，現在我們來看第二個健康習慣，那就是晒太陽。

So we're gonna talk about sun exposure in general and also sun exposure specifically in the morning.

是以，我們要談的是一般的陽光照射，以及特別是早晨的陽光照射。

Okay, so let's start with sun exposure in general.

好了，讓我們從一般的陽光照射開始。

Now, back in the day, having darker or tanned skin wasn't very desirable.

現在，在過去，皮膚黝黑或晒黑並不十分可取。

And so they used lead in skin whitening makeup to try and make their skin a little bit more fair, fair and beautiful as they say.

是以，他們在美白化妝品中使用鉛，試圖讓皮膚變得更白皙、更美麗。

The Greeks and Romans did this around 900 BC to 500 AD.

希臘人和羅馬人大約在公元前 900 年到公元 500 年間這樣做。

And from the 1500s to the start of the 1900s, this was fashionable across Europe and America as well.

從 1500 年代到 1900 年代初，這在整個歐洲和美國都很流行。

But then everything changed in the 20th century where going to holiday to a hot sunny country and then getting more tanned suddenly became fashionable.

但到了 20 世紀，一切都變了，去陽光充足的炎熱國家度假，然後晒得更黑，一下子成為了時尚。

But around the same time, scientists were discovering the links between UV radiation and skin cancer.

但與此同時，科學家們也發現了紫外線輻射與皮膚癌之間的聯繫。

So even though people still enjoyed spending time in the sun, we became more conscious of spending too long outside because we were worried about skin cancer.

是以，儘管人們仍然喜歡在陽光下消磨時光，但由於擔心患上皮膚癌，我們變得更加註意避免在戶外逗留太久。

We're told by doctors and dermatologists and big public health bodies to always wear sun cream, always put on your sunglasses and always wear a big hat to avoid sun exposure.

醫生、皮膚科醫生和大型公共衛生機構告訴我們，一定要塗防晒霜，一定要戴太陽鏡，一定要戴大帽子，避免陽光暴晒。

And apparently this was actually a famous campaign in Australia in the 1980s, Slip Slop Slap.

顯然，這其實是澳洲上世紀 80 年代的一項著名活動--"Slip Slop Slap"。

♪ Slip, slop, slap, slip on a shirt, slop on sunscreen ♪ ♪ And slap on a hat. ♪

Slip, slop, slap, slip on a shirt, slop on sunscreen And slap on a hat. Slip, slop, slop on a shirt, slop on sunscreen

And this means slip on a t-shirt, slop on some sun cream and slap on a sun hat apparently.

顯然，這意味著穿上一件 T 恤，塗上防晒霜，再戴上一頂遮陽帽。

So in some ways, sunlight has gotten a bad name for itself over the last 100 years because we've been really worried about skin cancer and ageing of skin.

是以，從某種程度上來說，陽光在過去的 100 年裡名聲不好，因為我們非常擔心皮膚癌和皮膚老化。

But the truth is that sunlight can be both harmful and also beneficial for us.

但事實上，陽光既可能對我們有害，也可能對我們有益。

So we need to find some sort of balance.

是以，我們需要找到某種平衡。

If you get too much exposure to sun and UV light, that can cause skin damage and ageing and contribute to skin cancer.

如果過度暴露在陽光和紫外線下，會造成皮膚損傷和老化，並誘發皮膚癌。

And if you look at this picture, this is a truck driver where because they've been driving on one side, half of their face has been sun exposed for a very long time and the other half hasn't.

如果你看看這張照片，這是一位卡車司機，因為他們一直是單側駕駛，所以半邊臉長期暴露在陽光下，而另一半臉則沒有。

And you can literally see the difference between what sun does to skin and what shade it does to skin.

從字面上就能看出陽光和陰影對皮膚造成的不同影響。

And there's actually a really clear association between sun exposure and living longer.

實際上，晒太陽與長壽之間有著非常明顯的聯繫。

So this graph, for example, shows different age groups along the X-axis and then their all cause mortality per 1000 person years along the Y-axis, i.e. how likely are they to die?

例如，這張圖在 X 軸上顯示了不同年齡段的人，然後在 Y 軸上顯示了他們每 1000 人年的全因死亡率，即他們死亡的可能性有多大？

This is what the line looks like for people who've been avoiding sun exposure.

這就是避免晒太陽的人的紋路。

This is what the line looks like for moderate sun exposure.

這就是中度日晒下的紋路。

And this is what the line looks like for people who have the most sun exposure.

這就是晒得最多的人的紋路。

Now, this doesn't seem like much, but if you zoom in on the graph, you can see that there's actually a pretty reasonable difference in all cause mortality between these different groups.

現在，這看起來並不多，但如果你放大圖表，就會發現這些不同組別之間的全因死亡率實際上存在著相當合理的差異。

So essentially, the more sun exposure you get, the lower your chances are of dying in terms of all cause mortality over time.

是以，從本質上講，晒太陽越多，隨著時間的推移，死於各種原因的機率就越低。

And researchers in 2011 even came to this conclusion.

2011 年的研究人員甚至得出了這樣的結論。

The overall health benefit of an improved vitamin D status from sun exposure may be more important than the possibly increased CMM risk, which is a type of skin cancer, resulting from carefully increasing UV exposure.

通過晒太陽改善維生素 D 狀態所帶來的整體健康益處，可能比小心增加紫外線照射可能導致的 CMM（一種皮膚癌）風險增加更為重要。

And there are lots and lots of reasons for this.

原因有很多很多。

So you probably know that UV rays from sunlight help our skin make vitamin D, which means we absorb calcium and phosphorus to strengthen our bones.

您可能知道，陽光中的紫外線能幫助我們的皮膚製造維生素 D，這意味著我們能吸收鈣和磷來強化骨骼。

In theory, you could take a vitamin D supplement, but actually, even though lots of governments and public health bodies recommend vitamin D supplementation, the actual evidence for it is a little bit mixed.

理論上，您可以補充維生素 D，但實際上，儘管許多政府和公共衛生機構都建議補充維生素 D，但實際證據卻有點參差不齊。

And what a lot of the studies around this show is that actual sun exposure is generally better for you than just taking a vitamin D supplement.

很多相關研究都表明，晒太陽比單純服用維生素 D 補充劑對人體更有益。

In fact, this very recent study in 2024 concluded that multiple trials of oral vitamin D supplementation show little benefit.

事實上，2024 年的這項最新研究得出結論認為，口服維生素 D 補充劑的多項試驗表明，其益處甚微。

So basically, the sun does things for our body that taking a vitamin D supplement doesn't really do.

是以，基本上，陽光對我們身體的作用是服用維生素 D 補充劑所無法做到的。

For example, you might not know that UV rays from sunlight actually causes our skin to release nitric oxide into our blood, and this makes our blood vessels relax and therefore reduces our blood pressure.

例如，您可能不知道，陽光中的紫外線實際上會使我們的皮膚向血液中釋放一氧化氮，從而使血管放鬆，從而降低血壓。

And that's why, for example, you can see decreases in blood pressure in summer compared to in winter.

這就是為什麼夏天的血壓會比冬天低的原因。

So sunlight helps protect against things like heart disease and strokes, and it also decreases our risk of things like obesity, autoimmune conditions like arthritis, and lots of different types of cancer as well, including apparently skin cancer.

是以，陽光有助於預防心臟病和中風等疾病，還能降低我們患肥胖症、關節炎等自身免疫性疾病以及許多不同類型癌症（顯然包括皮膚癌）的風險。

So what I'm personally taking away from this is that I should probably spend more time in the sun.

是以，我個人從這件事中得到的啟示是，我也許應該多花點時間晒晒太陽。

Yes, of course, I'm still gonna use my sun cream, but sun exposure is probably not as bad as we were led to believe.

是的，當然，我還是會使用防晒霜，但陽光暴晒可能並不像我們想象的那麼糟糕。

But the other thing around sun exposure is that if you are a fan of Andrew Huberman, which I am, he talks a lot about getting sun exposure first thing in the morning.

另外，如果你是安德魯-休伯曼（Andrew Huberman）的粉絲，我就是他的粉絲，他經常說要在早上第一件事就是晒太陽。

Now, because we are diurnal mammals, we wanna be alert and active during the day, and then we wanna be sleeping, obviously, at night.

現在，因為我們是晝伏夜出的哺乳動物，所以白天我們要保持警覺和活躍，晚上顯然要睡覺。

And we want all the cells and organs in our body to stay in sync with this day and night cycle, which is called our circadian rhythm or our internal clock.

我們希望體內的所有細胞和器官都能與這個晝夜週期保持同步，這就是我們的晝夜節律或體內時鐘。

Now, there is a region in the brain called the suprachiasmatic nucleus in the hypothalamus, which is our master clock.

現在，大腦中有一個區域叫做下丘腦上核，它是我們的主時鐘。

And this master clock sends signals to the rest of our body about whether to feel sleepy or awake.

而這個主時鐘會向我們身體的其他部分發出信號，告訴我們是該感到睏倦還是清醒。

Now, the cool thing about the circadian rhythm is that it's actually slightly longer than 24 hours.

現在，晝夜節律的神奇之處在於，它實際上比 24 小時稍長。

And so we need cues from our environment to keep it in sync.

是以，我們需要環境的提示來保持同步。

And that is why light is so important.

這也是光線如此重要的原因。

So our circadian rhythm is most sensitive to sunlight first thing in the morning, and also late at night, which enters through our eyes, hits the retina, and then sends signals to that master clock in our brain.

是以，我們的晝夜節律對清晨和深夜的第一縷陽光最為敏感，陽光通過眼睛進入視網膜，然後向大腦中的主時鐘發送信號。

So first thing in the morning, firstly, sunlight increases our cortisol levels to make us feel alert and focused.

是以，清晨的第一件事，首先是陽光會增加我們的皮質醇水準，讓我們感到警覺和專注。