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How To Reverse Nonalcoholic Fatty Liver Disease

如何才能造成非酒精性脂肪肝〈Nonalcoholic Fatty Liver Disease〉的迴轉

〈註：原圖源自於原文〉

The key to disrupting the vicious cycle of fatty liver disease before it damages the liver is exercise and diet.

要在脂肪性肝疾病損害肝臟前，阻斷脂肪肝疾病的惡性循環的關鍵在於運動跟日常飲食。

That’s right — Treating obesity of the liver is similar to treating obesity of the body. In fact, many scientific papers agree that the treatment of nonalcoholic fatty liver disease should be focused on controlling diabetes, obesity, insulin resistance, and hyperlipidemia. We should only focus on treating the liver in those with nonalcoholic steatohepatitis.

這樣沒有錯-改善肝臟的肥大的方法與減重的方式的確相近。事實上，許多相關的科學論文的內容正好認同非酒精性脂肪肝的療法是應該要將焦點放在糖尿病、肥胖、胰島素抗性及高脂血症〈hyperlipidemia〉等的病情控制。所以說，如果要讓造成非酒精性脂肪肝的迴轉，我們應該要把注意力放在非酒精性肝炎的治療方式。

This means that the best way to reverse nonalcoholic fatty liver disease and prevent liver damage is with a diet that has been proven to control diabetes, obesity, insulin resistance, and hyperlipidemia

這代表著，利用改善飲食這樣的方式是迴轉酒精性脂肪肝與預防肝的損傷的最佳方式，而且這種方法也被證實對於糖尿病、肥胖、胰島素阻抗及高脂血症的控制是有效的。

Luckily, this diet already exists and has been found to more effective than caloric restriction and low-fat diets. This diet is called the ketogenic diet. A diet that focuses on restricting carbohydrates, removing one of the main drivers of fatty liver disease from the diet.

很幸運的，我們無須為了治療非酒精性脂肪肝，還特地尋找適合的飲食方式，因為這種方法比控制熱量和低脂飲食還要更有效〈你看，這種飲食法是不是容易多了呢〉。這種方法稱為生酮飲食，簡單來說就是限制水化合物的攝取量，而這樣正好去除了飲食中最主要造成脂肪肝疾病的成因。

However, we cannot call the ketogenic diet the ideal diet for fatty liver disease yet. This is only a theory that is based on evidence for how the ketogenic diet helps people with issues related to nonalcoholic fatty liver disease. To see what works best for the disease itself, we must dig through the research.

雖然到目前為止，我們不能將生酮飲食稱做治療脂肪肝疾病的理想飲食方式。而且這樣的理論基礎是源自於生酮飲食對於罹患與非酒精性脂肪肝相似疾病的人是有幫助的。為了要了解到底要用什麼方式才最適合治療這樣的疾病，我們需要更深入地探討相關的研究。

What Is The Best Fatty Liver Reducing Diet and Lifestyle?

抑制脂肪肝的最佳飲食法以及生活方式

〈註：原圖源自於原文〉

In a review of studies on nonalcoholic fatty liver disease treatments, the researchers found that weight loss leads to a substantial improvement in the disease. Weight loss of 3-5 % improves fatty liver disease, but to reduce inflammation and liver damage, a weight loss of 10% may be needed. To accomplish this, researchers used the most well-known way to promote weight loss: caloric restriction and exercise.

在非酒精性脂肪肝療法的相關研究的文獻回顧中，研究人員發現，減重會大幅改善病情。百分之三至五的減重幅度會改善脂肪肝，但是要抑制炎症以及肝的損傷，需要百分之十的減重幅度才能辦到。為了要達到這樣的幅度，研究人員就試用控制熱量以及運動這種最常見的方式來減重。

Let’s start with exercise. Physical activity alone improves insulin sensitivity and reduces fat in the liver.

先從運動的效果講起，單就運動來說的確能改善胰島素敏感度且能減少肝臟裡的脂肪。

In fact, one study kept the body weight of their subjects constant while they implemented an exercise training program. They found that it leads to a distinct decrease in liver fat.

但是事實上，有一項實行運動計畫搭配維持相同體重的研究中，結果顯示，這樣的方式會明顯造成肝臟脂肪量的下降。

In studies that combine caloric restriction with exercise, the results are even more promising. For example, one study took twenty-five obese patients with fatty liver and put fifteen of them on a calorie restricted diet and exercise program for 3 months.

在搭配熱量控制與運動的研究顯示，這樣的效果會更明顯。以其中一項研究為例，25位有脂肪肝的肥胖的病患當中，研究人員挑了其中的15位進行為期3個月的熱量控制飲食法並搭配運動計畫。

The calorie restricted diet was based on a daily calorie intake of the patient’s ideal weight in kilograms multiplied by 25 calories, and the exercise program is described as “walking or jogging”.

飲食方面，研究人員將熱量控制在體重的25倍〈也就是體重〈kg〉*25大卡〉，而慢跑或是走路則是實驗中採取的運動方式。

The researchers found that the treatment group’s “weight, blood biochemical data such as aminotransferase, albumin, cholinesterase, total cholesterol and fasting blood glucose values, and steatosis (fatty liver) were significantly decreased after the trial.  In the control group, there were no significant differences in the clinical and histological findings before and after the trial.”

研究人員發現，實驗組〈也就是這15位〉的〝體重、血液生化〈blood biochemical〉指標〞像是轉氨酶〈aminotransferase〉、白蛋白〈albumin〉、總膽固醇〈total cholesterol〉和空腹血糖值〈fasting blood glucose values〉和脂肪變性〈steatosis〉〈脂肪肝〉的數值在經過實驗後都下降了。在控制組〈剩下沒參與的那十位〉在臨床和顯微解剖學的研究結果中，歷經了實驗後並無任何明顯的改變。

It’s that simple. Eat less and move more, and you can reverse fatty liver disease. Many review articles on the treatments for nonalcoholic fatty liver disease also agree on this simple principle, but they don’t agree upon what kind of exercise to do.

能有這樣的實驗結果，其實是很容易就能理解的。吃少動多您就能迴轉脂肪肝疾病了。許多非酒精性脂肪肝療法的相關回顧性的文章也同意這樣的原則，但對於運動的方式並沒有獲得共識。

Many studies have been done on different types of exercise and their effects on fatty liver disease, but there is not enough data to come to a clear conclusion about what is best. However, we do know what is better — doing the exercise that you will actually do.

目前已經有針對各式各樣運動和它們在改善脂肪肝疾病的效果的研究，但並沒有足量的資料是可以獲得更明確的結論。不過好消息是，只要作您平常做的運動就會有效果。

The jury is still out on the best diet for nonalcoholic fatty liver disease as well. We know for certain that restricting your calories helps, but another diet may provide even better results, making it worthy of the name “fatty liver diet”.

對於非酒精性脂肪肝的控制最有效的飲食方式到目前為止仍舊沒有明確的答案。我們目前確定的是，控制熱量的攝取的確幫助改善病情，但是有一種飲食法可能提供更好的效果，而這樣的效果足以讓它稱作〝治療脂肪肝的最佳飲食法〞。

The Ketogenic Diet May Be The Best Fatty Liver Diet

生酮飲食可能就是最適合改善脂肪肝的飲食

〈註：原圖源自於原文〉

We mentioned before that weight loss is essential when reversing nonalcoholic fatty liver disease, and an even greater reduction in weight loss is helpful for patients with nonalcoholic steatohepatitis. The best way to achieve this weight loss, however, is not with caloric restriction.

我們在文章前面曾提過，當要迴轉非酒精性脂肪肝症狀時，就需要減重，而且如果減重幅度越大對於罹患非酒精性脂肪肝的病患就有越大的幫助。也就是說最好迴轉此症狀的方式就是減重了，但是，熱量控制並不是減重最好的方法。

In fact, many studies conclude that caloric restriction is inferior to a low-carbohydrate, ketogenic diet when it comes to weight loss. For example, one study split 132 people into two groups: a low-carbohydrate diet (30 grams or less of carbohydrates a day) group and a calorie-restricted, low-fat diet group.

看到目前為止，您一定會覺得很奇怪對吧。一般來說，熱量控制不就等於是減重嗎？先別急，往下看就知道原因了。事實上，許多研究顯示：熱量控制法的減重效果沒有低碳飲食或是生酮飲食來得好〈相關說明看這篇：大學生小廚房《TDEE迷思：不是要吃基礎代謝+300嗎？| 代謝補償 | 甚麼是TDEE？ 》〉。例如，其中一項研究將132個人分為兩組：低碳飲食組〈每日碳水化合物攝取量控制在30克以內〉及熱量控制搭配低脂飲食組。

After six months of this dietary intervention, the researchers concluded that “severely obese subjects with a high prevalence of diabetes and the metabolic syndrome lost more weight in a six-month period on a carbohydrate-restricted diet than on a fat- and calorie-restricted diet.”

在歷經了六個月的實驗後，研究人員得出了這樣的結論：嚴重過胖且有罹患糖尿病及代謝症候群高風險的人減掉的體重經過六個月後，採用低碳飲食的減重幅度優於熱量控制搭配低脂飲食組。〈註：實驗結果為：低碳飲食組減去的平均體重為8.6公斤，而熱量控制搭配低脂飲食組則是4.2公斤〉

The ketogenic diet has also been proven in multiple studies to be more effective than a calorie-restricted diet at reversing type 2 diabetes, obesity, heart disease, and hyperlipidemia. This must mean that it is effective for nonalcoholic fatty liver disease as well, right?

在其他許多的研究中也證實了，生酮飲食在迴轉第二型糖尿病、肥胖、心臟病及高脂血症的效果是比熱量控制的飲食法來得更加有效。那麼這一定就代表著低碳或是生酮飲食也對非酒精性脂肪肝有效，嗎？

A recent pilot study put five patients on the ketogenic diet ( less than 20 grams per day of carbohydrate). At the end of six months, the average weight loss was 28 pounds, but this wasn’t the most surprising finding. Each patient underwent a liver biopsy, and four of the five patients showed a reduction in liver fat, inflammation, and fibrosis. This provides preliminary evidence that the ketogenic diet can reverse fatty liver disease and nonalcoholic steatohepatitis.

在近期的一項先導性研究〈pilot study，如果看完連結或是不想看的話還是不懂沒關係就略過吧〉中，研究人員選了五位罹患脂肪肝的病患，並讓它們採用生酮飲食〈每天的碳水化合物的攝取量控制在20克以內〉。在經過六個月後，這五個人平均減了28磅〈約12.7公斤〉，但這並不是最讓人驚豔的實驗結果。在經過肝穿刺切片檢查〈liver biopsy〉後，其中有四個病患的肝脂肪、炎症及纖維化的程度有下降。這樣的實驗結果提供了這樣的初步證據：生酮飲食可以迴轉脂肪肝及非酒精性脂肪性肝炎。

However, this is a small pilot study (and the patients took supplements as well). To get a clear answer, we must find more studies on the ketogenic diet and fatty liver disease.

但是上述就只能算是一個小型的先導性研究〈而且參與研究的病患也有吃藥壓〉。為了要得到一個明確的答案，我們需要去找更多有關生酮飲食及脂肪肝疾病的研究。

In a 2016 meta-analysis and systematic review on the effects of low carbohydrate diets on liver function tests in nonalcoholic fatty liver disease patients, the researchers’ conclusions were not as promising.

在一項2016年針對低碳飲食在非酒精性肝病病患的肝功能實驗的整合性分析及系統性回顧中，研究人員所作出的結論並不像前述所說的那麼樂觀。

They found that the low carbohydrate diet decreased fat in the liver significantly, but the liver function tests did not improve. The measurements they looked at to determine liver function were the liver enzymes (AST, ALT, and GGT) that are usually elevated in patients with nonalcoholic fatty liver disease. As a result of the low carbohydrate diet, these levels decreased, but not enough to be statistically significant.

他們發現，低碳飲食法的確能明顯地減少肝裡的脂肪量，但是肝功能並沒有因此獲得改善。其中他們的判別指標為肝消化酶〈AST、ALT、AGT〉，而罹患非酒精性脂肪肝的病患，這些指標都比一般人來得高。在採用低碳飲食後，這些指標的確有降低，但降低的幅度並不明顯。

When we look more closely at the studies in the meta-analysis, they either found no effect on liver enzyme levels or a significant effect. In other words, the liver function of some people stayed the same on the low-carbohydrate diet while others improved significantly. Why the difference?

當在更深入利用整合分析來看這些研究時，研究人員發現，低碳飲食對於肝消化酶水準只有小量或甚至完全沒有任何的影響。換句話說，有些人的肝功能在歷經低碳飲食後，並沒有作改善，但也有些人有改善，那麼為什麼會有這樣的差異呢？

Two factors that we talked about earlier could be at the root of the differences between studies. These factors are genetics and gut health.

這樣差異的原因正好與本系列文章的第一篇裡所提及的基因及腸道健康這兩項不謀而合。

Some people were born with a set of genetic variants that make it harder for them to adapt to the low carbohydrate diet, which may lead to a minimal improvement of liver function. It is possible, however, that these people could get better results if they stay with the diet longer.

有些人一生下來就有一組基因變體〈genetic variants〉使得他們的身體較難去適應低碳飲食，這可能也是為何採用這種飲食法後肝功能的改善幅度小的原因。這樣的基因的緣故是合理的，但是，如果這些人採用生酮飲食的時間再更長的話，就會得到更好的效果。

Gut health is another important variable to consider. When many people first try a high-fat, low-carb diet, they may focus on all of the fatty meat and cheese they can eat and forget about eating vegetables. Excess fat consumption with very little fiber can cause the gut microbiome to change tremendously. This leads to more lipopolysaccharides being absorbed and more inflammation in the body and the liver.

另一個需要考量的重要變因為腸道的健康狀況。當許多人剛開始採用高脂肪低碳水化合物的飲食方式時，他們可能只在意攝取大量高油脂的肉類跟乳酪卻忘了要吃蔬菜。過量的脂肪攝取，然後只攝取一點點的膳食纖維可能會大幅度讓腸道裡的微生物改變。這會造成替體內及肝臟吸收更多的脂多醣〈lipopolysaccharides〉並會造成這兩者更容易有炎症的現象。

To optimize your diet to reverse disease, especially fatty liver disease, it is imperative to have low-carbohydrate vegetables with every meal. The combination of vegetables and carbohydrate restriction is what makes an ideal fatty liver diet.

為了要讓您的飲食方式更能迴轉疾病，特別是脂肪肝疾病，搭配低碳水化合物含量的蔬菜〈低碳蔬菜〉是很重要的。低碳蔬菜的攝取與控制碳水化合物這兩者搭配是改善脂肪肝最理想的飲食方式。

全文連結：Keto: The Best Fatty Liver Diet