BBC Learnings · Section 4
Personalised diets
In recent years, new diets with names like vegan, keto and paleo have become very popular.
Level: B2 · 82 sentences
Transcript
- In recent years, new diets with names like vegan,
- keto and paleo have become very popular.
- Are you a vegetarian, Neil?
- Do you follow any particular diet?
- Well, I eat lots of fresh fruit and vegetables and only a little meat from time to time.
- Well, while many diets claim to improve health or help you lose weight,
- recent research shows that what counts is not what you eat,
- but how your body reacts.
- Yes, and that reaction doesn't happen where you might think not in the brain,
- or tongue, or even the stomach, but in the gut another name for the intestines.
- the long tube inside your body which digests food.
- Inside everyone's gut are millions of microbes tiny living organisms too small to see without a microscope.
- Some of them are good for us, some bad.
- Microbes help digest food, but they influence our bodies more than we know.
- Think of them as chemical factories that cause our individual reaction to the food we eat.
- This mix of gut microbes is unique and different for everyone.
- even identical twins.
- And it's the reason why some doctors now recommend a personalised diet
- one that perfectly fits your own unique combination of microbes.
- We'll hear more soon, but first I have a question for you, Neil,
- and it's about the gut the tube which includes the large and small intestine.
- It's very long, but how long exactly is the average adult's gut?
- Is it a three and a half metres?
- b five and a half metres or c seven and a half metres?
- Well, everybody is different of course,
- but I'll say on average the gut is b five and a half metres long.
- OK, Neil, I'll reveal the answer later in the programme.
- Among the first to investigate gut microbes was Dr Tim Spector,
- author of the bestselling book The Diet Myth.
- He wanted to check whether the dietary advice he had heard
- and believed advice like eat little and often
- or avoid fat was really true.
- Listen to Dr Spector explain how he started to doubt some of this advice.
- Food myths, he calls them, to BBC Radio 4 programme The Life Scientific.
- All these so-called myths that I'd believed, whether it was about calories,
- about fats, when to eat, how to eat, were based on...
- flimsy or no evidence, very old,
- very poor quality and had been repeated so much that people didn't think to question them.
- One of the food myths Dr Spector questioned was counting calories,
- the units which measure the amount of energy food provides.
- He discovered that much of the dietary advice he had heard was either incorrect or based on flimsy evidence.
- If evidence is flimsy, it's weak and unconvincing.
- As Dr Spector questioned these food myths,
- he remembered an earlier study involving identical twins pairs of brothers or sisters with the same genes.
- It was the surprising differences in weight between one twin
- and another that made Dr Spector realise
- that no two people have the same gut.
- Even identical twins' guts are different.
- But, as he told BBC Radio 4's The Life Scientific,
- the discovery came in a very smelly way,
- by asking his volunteers to send samples of their poo in the post.
- We collected lots of these samples, sequenced them,
- and then looked at twins where one was overweight and one was skinny.
- And we found in every case, the skinnier twin had a more diverse microbiome,
- greater numbers of different species.
- And they also nearly also had high numbers of a couple of microbes.
- that just stuck out of the crowd and one was called Christensenella and the other one's called Akkermansia.
- Although genetically identical,
- one twin was overweight while the other twin was skinny or very thin.
- Because the weight difference could not be explained genetically,
- Dr Spector suspected the microbes in the skinnier twin's gut held the answer.
- The more diverse someone's microbes, the better their gut was at digesting food.
- regulating fat and maintaining health.
- Two microbes, Christensenella and Acromantia, were especially effective.
- Dr Spector says these microbes stuck out of the crowd,
- meaning they were easy to notice for their positive effect.
- And since everyone's microbes are different,
- it follows that a personalised diet which selects the friendliest food for your gut is best.
- Right, and all this talk of eating is making me hungry.
- So tell me, Sam, was my answer to your question right?
- Ah yes, I asked about the length of the gut in the average adult.
- I said it was five and a half metres.
- Which was the correct answer.
- Well done, Neil.
- That took guts, which is the second meaning of the word courage.
- OK, let's recap the vocabulary we've learned, starting with gut,
- an informal word for the intestines, the tube, which digests food from the stomach.
- Microbes are microscopic organisms living inside the body.
- A calorie is a unit measuring how much energy food provides.
- If an argument or evidence is flimsy, it's weak and hard to believe.
- A skinny person is very thin.
- And finally, if something sticks out of the crowd, it's noticeable in a good way.