Eating a healthy diet that encourages the growth of 'good' bacteria in your gut doesn't mean swapping all your guilty pleasures for leafy vegetables and expensive superfoods.
In his new book , Dr Michael Mosley explains how your guts have an amazing degree of control over your mood, hunger and general health, so it's important to keep your gut bacteria well-fed with food that improves the health of your biome. It's a topic he also tackles in Gut Feeling, a special episode of Insight screening now available on , or watch it below. )
Some foods are definitely much better than others for "keeping your gut garden in good shape", but Dr Mosley is dismissive of the term 'superfoods'.
"'Superfood' is unfortunately a term often used to basically flog you something which is incredibly expensive and is no better for you than cabbage," Dr Mosley tells SBS.
"So I think cabbage is a superfood, I think that many vegetables are what I would call superfoods, I think betroot is a superfood. But whether it is a sexy superfood is another matter.
"All I'd say is these are foods which are absolutely nutrient-packed, which are very tasty and which provide you with elements which you may not be getting from the rest of your diet."
Watch Dr Mosley on Insight, or keep reading for his thoughts on four gut-friendly foods:
The good news is that some of your favourite foods are also surprisingly good for your gut health.
Cocoa
"Cocoa is full of flavenoids and good things, and the major downside is the sugar," Dr Mosley says.
"It's when you pump it full of sugar and reduce the cocoa content that it's more ambiguous, so I'm afraid the lovely milk chocolate stuff is unlikely to be terribly good for you."
"Traditionally the Mayans or the Aztecs or whoever first grew it and developed it and they drank it as a bitter chocolately drink, and there are peoples in the world who still do that. And there's good evidence that drunk in that form it's bloody good for you."
In The Clever Guts Diet, Dr Mosley explains that cocoa is broken down in your colon to produce nitric oxide, which is good for your cardiovascular system, while also being a great source of flavonoids and polyphenols, which aid your gut bacteria.
Satisfy your chocolate cravings with these from Mosley's new book.
Strange as it may sound, there is eggplant in this dark chocolate brownie. Definitely don't knock it 'til you try it. Source: Simon & Schuster
He gives the thumbs up to dark chocolate with a cocoa content of 70 per cent or more, or drinking unsweetened hot cocoa.
"So I often have a glass of milk with cocoa, but without sugar in it," Dr Mosley says.
"I don't have hot chocolate, I have cocoa. And there's quite a lot of sugar in milk anyway, so it naturally sweetens it. It helps me sleep as well.
"So cocoa, hurrah! Rehabilitated!"
Wine
"On the face of it, your microbiome should really hate alcohol. Pure alcohol is death to anything that is microscopic," Dr Mosley writes in the book.
"But alcoholic drinks contain more than just alcohol. They also contain polyphenols."
Polyphenols are chemicals which have a powerful influence on the microbiome. They are found in tea, coffee, fruit, vegetables, chocolate and wine.
Dr Mosley cites a Spanish study in which researchers recruited 10 healthy middle-aged men, who were randomly allocated to either drinking a large glass of red wine (270ml), alcohol-free red wine, or gin (100ml) nightly with dinner. After 20 days they switched regimes, and throughout they gave blood and stool samples.
"What the researchers found is that when the volunteers were drinking the red wine, and to a lesser extent when they drank the de-alcoholised wine, there were significant drops in blood pressure, in C-reactive protein (CRP - a measure of inflammation) and in their triglyceride levels (the amount of fat circulating in the blood)," he writes.
"In addition, there was a marked change in their gut bacteria, with a particular increase in Bacteroidetes, the type of bacteria associated with slimness. They also noticed a significant increase in Bifidobacteria, which are associated with lowering cholesterol."
But not all alcohol is equal. Red wine seems to be more beneficial than white wine, and there have been no obvious health benefits attributed to spirits.
As for beer, Mosley tends to agree with the nickname "liquid toast" given its high carbohydrate content.
"If you are trying to lose weight or if you have sulphur-reducing bacteria in your gut, then beer is definitely a no-no," he says.
Cheese
You know what goes well with wine? Cheese! And Dr Mosley is a fan of both.
"I love cheese but I gave it up for many years because it contains a lot of saturated fat and this, I assumed, was likely to lead to an early grave," he writes in his new book.
"I tried eating low-fat cheeses but they tasted terrible. Then I looked into the science and realised there is no evidence that eating low-fat cheese has any particular health benefits over eating the full-fat version. So I returned to eating proper cheese and have enjoyed every mouthful ever since."
It turns out your gut bacteria quite likes cheese too.
Source: Simon & Schuster
When questioning why the French, who eat about 20 kilograms of cheese per person every year, and yet have relatively low rates of heart disease and obesity.
"It could be something to do with the fact that they drink lots of wine, or maybe there is something special about their lifestyle, but gut bacteria may also play a part," Dr Mosley writes.
He points to a , in which 15 young men were fed either a diet full of cheese and full fat milk or a control diet for two weeks. The weeks when they ate milk or cheese there were higher levels of butyrate and propionate in their stools - two compounds produced by the biome that have been shown to be good for the gut. It's only a small study, but interesting.
But some cheese is more beneficial others, as not all cheese contains live bacteria. Processed cheese contains virtually none. The cheeses that contain signifcant good bacteria are Gouda, mozzarella, cheddar and cottage cheese, and some blue cheese such as Roquefort.
It's a cheese lover's dream come true. Source: iStockphoto
And feta is rich in Lactobacillus plantarum bacteria, which produces anti-inflammatory compounds.
Apples
An apple a day keeps the doctor away? Well, not quite. But they definitely get a tick of approval from Dr Mosley, who says they are one of the healthiest fruit you can eat (as long as they are eaten whole and not as a juice).
They are a good prebiotic, which is a kind of plant fibre that your body can't digest but which encourages the growth of good bacteria in your gut. Dr Mosley likens prebiotics to fertiliser for good bacteria.
Apples are also low in sugar, high in pectin, high in polyphenol antioxidents, and they increase the production of butyrate, the short-chain fatty cid that feeds 'good' bacteria.
"I love stewed apples, with yoghurt, or diced and cooked in the oven with a scattering of cinnamon," says Dr Mosley.
The Clever Guts Diet by Dr Michael Mosley with Tanya Borowski and Dr Clare Bailey (Simon & Schuster Australia, pb, $29.99) is on sale June 1. Catch Michael Mosley on Insight in Gut Feeling as he talks about gut health and the microbiome, now available on .
