Inulin, and fructooligosaccharides (FOS), Seem to Boost Brain Function in Older Adults

What’s good for your aging gut may also be good for your aging brain. The first twin study of its kind suggests that taking daily protein and prebiotic supplements can improve scores on memory tests in people over the age of 60.

The double-blinded trial involved two cheap plant fiber prebiotics that are available over the counter in numerous nations around the world. Prebiotics are non-digestible consumables that help stimulate our gut microbes.

One is called inulin, and it is a dietary fiber in the class fructan. Another is called fructooligosaccharides (FOS), and it is a plant carbohydrate often used as a natural low calorie sweetener.

To test the effect of these supplements on the aging brain, researchers at King’s College London enrolled 36 twin pairs over the age of 60. Each duo was randomly split so that one twin was assigned a daily prebiotic in a protein powder and the other was assigned a daily placebo in a protein powder.

The twin who unknowingly took inulin or FOS generally scored higher on a cognitive test three months later.

Open Access Paper:

Effect of gut microbiome modulation on muscle function and cognition: the PROMOTe randomised controlled trial

Studies suggest that inducing gut microbiota changes may alter both muscle physiology and cognitive behaviour. Gut microbiota may play a role in both anabolic resistance of older muscle, and cognition. In this placebo controlled double blinded randomised controlled trial of 36 twin pairs (72 individuals), aged ≥60, each twin pair are block randomised to receive either placebo or prebiotic daily for 12 weeks. Resistance exercise and branched chain amino acid (BCAA) supplementation is prescribed to all participants. Outcomes are physical function and cognition. The trial is carried out remotely using video visits, online questionnaires and cognitive testing, and posting of equipment and biological samples. The prebiotic supplement is well tolerated and results in a changed gut microbiome [e.g., increased relative Bifidobacterium abundance]. There is no significant difference between prebiotic and placebo for the primary outcome of chair rise time (β = 0.579; 95% CI −1.080-2.239 p = 0.494). The prebiotic improves cognition (factor score versus placebo (β = −0.482; 95% CI,−0.813, −0.141; p = 0.014)). Our results demonstrate that cheap and readily available gut microbiome interventions may improve cognition in our ageing population. We illustrate the feasibility of remotely delivered trials for older people, which could reduce under-representation of older people in clinical trials. registration: NCT04309292.

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Thanks for great share @RapAdmin

People, this is a good companion thread

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It’s Just - Inulin Prebiotic Fiber

Have you used this one @RapAdmin ?

Anyone else have suggested brands?

Yes - the price is good ($0.74 per oz) and seems good quality. I’ve purchase it a few times. Will do again I think, unless I find a better deal for a quality product.

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Good to know! Trehalose is supposed to be very helpful too.

also found this re brands that people use

In powder:

Or in capsules

@ng0rge and @RapAdmin what’s your protocol / dosing, meal timing? Any other “best practice” when starting?

I’ve cut the dose down to a little less than a teaspoon in my midday green tea. It does cause a little gas and you can feel that it keeps things moving through your intestines - keeps you regular. So not on an empty stomach. I trust that it’s keeping my gut microbiome happy. Just one dose daily. I use the powder (NOW brand).

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I take ca 700 grams of onions weekly average 100 daily.
Per 100 grams onions have 1-8 g of inulin, 2-6 g of FOS, the wide range in large part depending on where it´s grown.
Assuming 2,5g inulin, 3g FOS per 100 grams will give me those amounts daily on an average.


Nothing too complex, I just toss in a heaping large spoonful of inulin into my smoothies in the morning (which I make a couple times a week).

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Or just eat garlic, onions, whole wheat/barley/rye and cruciferous vegetables, plenty of fructans there… unless you have IBS, then it’s a gut bomb.

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I’ve got “IBS”. I did the FODMAP elimination diet and found that fructans and polyols were a problem most of the time. Since I started making homemade yogurt with inulin I have found that I’m very tolerant to it (I can eat loads of the stuff). It’s also improved my gut health in general (the yogurt). Gone are the long nights waking up at 3am with horrible stomach issues. It’s been a few years of effort and trying new things but well worth it. I’m convinced my IBS was caused by regular use of erthromycin for chronic tonsillitis in my 20’s.