5. SSF Method and Gut Health（SSFメソッドと腸の健康）
何事にも言えることですが、良いものでもやりすぎは禁物です。腸の健康のためのファスティングとは、通常は16〜36時間の断食をときどき（1〜3週間に1回程度）行うことを指します。これ以上行うと、菌が育つために必要な栄養が枯渇しすぎてしまいます。有益な菌が死に始めると、いわゆる日和見菌（より有害な菌）が増え、腸内ディスバイオーシスを招きます。同様に、ファスティングのやりすぎは腸の粘液産生も低下させます。この粘液層は食べ物によって補充される必要があり、それがないと重要な層が失われてしまいます。その結果、腸の細胞がダメージにさらされやすくなり、リーキーガットにつながります。
原文（英語）を表示
### **The Crossover: SSF METHOD for Gut Health**
Fasting is another powerful tool that we can use to support the health of your gut, and its completely free. Here are some of the ways in which it helps:
**Microbiome Benefits:** As you now know, the gut contains trillions of small bacteria that all play important roles in areas from digestion to immunity and mood. Well, incorporating some fasting will improve the diversity of these bacteria, whilst increasing the prevalence of beneficial bacteria and decreasing the abundance of harmful bacteria. This happens because there is less food coming into your system, creating a less favourable environment for the dominant bacteria (that depend on this continuous supply) of food to survive. This allows those slower-growing/less competitive (but still beneficial) bacteria a chance to thrive and grow, overall leading to increased microbiome diversity. A particular bacteria called Akkermansia is a great example of one of these less competitive, but still significant bacterium. This bacterium in particular thrives on substances called mucins and glycoproteins, both found in the gut mucus lining. When you fast, the Akkermansia stops getting nutrients from food, and so starts feeding on these endogenous sources, allowing them to thrive. why is this good? Well, Akkermansia has been shown to reduce leaky gut, and thus inflammation, but even more significantly, it improves your metabolism by increasing compounds called GLP-1 and PYY, both of which either improve insulin secretion and glucose metabolism, or reduce appetite. Finally, in terms of microbiome benefits, fasting not only increases beneficial bacteria, but also reduces the harmful bacteria population. Basically, pathogenic (harmful) bacteria often rely on a constant supply of sugar and nutrients for them to grow and outcompete the beneficial nutrients. Well, fasting cuts off this supply and allows the beneficial bacteria to dominate. This reduces what is called gut dysbiosis and inflammation.
**Gut Lining Benefits:** Aswell as microbiome benefits, fasting directly improve the gut lining's integrity aswell. When you fast, your body enters a state called autophagy as we have discussed previously. This is where the body regenerates cells and repairs old tissues etc. This process also applies to the gut lining, and leads to reduced leaky gut, leading to reduced inflammation.
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### **Beware of Overfasting: Gut Damage**
Like with anything there in life, there does exist too much of a good thing. Fasting for gut health normally just means a 16-36 hour fast every once in a while (every 1-3 weeks or so). Doing more than this, however, can overdeplete the bacteria of the food they need to thrive and continue to grow. When beneficial bacteria start to die from this, so-called opportunistic bacteria (more harmful), start to grow, leading to gut dysbiosis. Similarly, overfasting depletes mucus production in the gut. This mucus layer needs replenishment from food, and without this, this crucial layer is depleted. This leads to increased exposure of intestinal cells to potential damage, leading to leaky gut.
There are actually more methods in which overfasting damages the gut, but this is the basic idea - **fasting is a good tool, but should not be overdone.**