Dr. Sarah Berry
speaker
566 appearances
3 recordings
3 series
first heard Nov 2024
last heard 18 Dec
Dr. Sarah Berry’s voice in public audio — every appearance, attributed to the second.
Trend
recordings per month · last 12 monthsRecordings per month over the last 12 months — 1 in all, peaking in Dec 2025 with 1.
Appearances
When you swallow it, you chewed it a little bit, I assume.
When people chew it, we know from these lovely chew and spit studies or mastication studies that we do that at the point at which you swallow a nut, the particles, i.e. the size of the bits that you're swallowing that you've chewed, are about maybe half a millimetre to one millimetre in size.
Now, given that this cell of an almond nut is about 50 microns, that means when you're swallowing, within that what we call a macroparticle, you've still got thousands of cells. They're intact, where you've got this lovely cell wall containing all of this fat. And so you're swallowing these intact cells containing, encapsulating the fat. So they're what we call very low by accessibility.
They're not very accessible to us, this fat. Now, what happens is this passes through your gastrointestinal tract. Some of the enzymes can break down the cells a little bit. But actually a lot just comes out the other end. So I don't know whether you've ever eaten a bag of nuts and looked at your poo after.
Go and do that. But you should see some almond particles.
You know, like when I'm, you know, being a mum, when I've looked at a lot of poo in my life through my work, but also through being a mum, you can see whole nut particles in the poo.
So they break down partially. So you break down about 10% in the mouth before you swallow. So about 10% of the calories become available because the calories are contained from the fat, etc. And then you probably break down about another 60% to 70% as it passes through your stomach, your small intestine, your large intestine.
But you have loads of material arriving at your colon, which is your large intestine, that's undigested, which is good for two reasons. One, because you're giving all of this food to your microbiome, which we know is great for your health. Your microbiome is having a party with these nuts.
But also, if you are worried about eating nuts because of their high calorie value, actually 20% to 30% of the calories are just coming out the other end.
But where it gets really interesting is if we then take exactly that nut that you're holding there, and if I was to industrially grind it so that I broke all of those cells walls, so we're breaking it down to less than 50 microns so that you're releasing all of the fat, right? So it becomes 100% bioaccessible, i.e. you absorb 100% of it.
But they could have two identical backup pack labels because they're the same ingredient. All that's happened is you've ground that nut to such an extent that you've released everything. And so having that in its whole form is beneficial because if you are concerned about energy intake, it's reducing the energy. It's providing this amazing food for your gut microbiome.
It's changing also how your blood changes metabolically in that about eight hours after eating it. And this is what I've done lots of work on, looking at how your blood fat increases and decreases in that immediate period after eating either groundnuts or whole nuts. But once you grind it,
I'm not saying it's necessarily bad because the upside of that is all of the other good nutrients contained within that cell, like the vitamin E and some of the other components also become available. So it's this double edged sword.
But that's what I think is so fascinating about processing and about food matrix and why we have to move beyond thinking about food just in terms of the nutrients. Because you can have two foods with identical backpack labeling that have different effects. And we've seen the same with oats. We've been doing studies. as well, where we feed people large oats.
So kind of, you know, like the steel cut sort of old fashioned porridge, or you feed people finely ground oats. And so we've done clinical trials where on one occasion people come in and they'll have 50 grams carbohydrate for breakfast of these large oats. Then they'll come in another day and they'll have exactly the same oats, but where we ground them.
Literally, we've got students just grinding them down. So they're more like a powder. And the difference in the metabolic response in that following six hours after having either the large traditional oats or these finely ground oats is enormous.
Yes. So with the nuts, what we're seeing here is a difference in the amount. as well as the speed. With the oats, what we're seeing is a difference in the speed. So we're seeing a difference in the rate because we know that the food matrix impacts the amount, i.e. with the nuts, the rate, i.e. with the oats, and as well as where the food's absorbed in the gut.
And so you see about a 40% difference in the postprandial glucose response. So this is the increase in circulating blood glucose after you've had these oats. We see about a 50% higher response from the ground oats versus the large oats. And that has subsequent impacts on hunger hormones, fullness hormones...
So fibre is a really interesting one. And it's a really interesting one because we know we're not getting enough fibre. So we should be getting at least 30 grams of fibre. In the UK, and it's similar in the US, we get on average about 20 grams of fibre. 95% of us are not having enough fibre.
Fibre is the one nutrient that we know consistently is associated with beneficial health effects, reduced reduction in many cancers, reduction in cardiovascular disease, reduction in levels of obesity, type 2 diabetes, etc., You know, it's an amazing nutrient fiber and we don't get enough of it.
Showing 121–140 of 566 · page 7 of 29
← Previous
Next →