1 00:00:06,000 --> 00:00:09,440 Speaker 1: Everyone, Welcome to another edition of Wisdom Wednesdays. Today, I 2 00:00:09,480 --> 00:00:11,520 Speaker 1: want to talk about something that most of us consume 3 00:00:11,720 --> 00:00:15,239 Speaker 1: every day, which is coffee and tea, and how they 4 00:00:15,320 --> 00:00:20,520 Speaker 1: might influence our risk of neurodegenerative diseases, including Alzheimer's, Parkinson's, 5 00:00:20,920 --> 00:00:24,200 Speaker 1: and vascular dementia. There's been a lot of research over 6 00:00:24,239 --> 00:00:28,240 Speaker 1: the years looking at coffee or tea individually, but a 7 00:00:28,240 --> 00:00:32,000 Speaker 1: new study using data from the UK Biobank, which I've 8 00:00:32,040 --> 00:00:34,120 Speaker 1: talked about before. This is the gift that keeps on 9 00:00:34,240 --> 00:00:37,760 Speaker 1: giving for research, but this study looked at something slightly different. 10 00:00:38,080 --> 00:00:40,400 Speaker 1: Instead of looking at coffee and tea in isolation, the 11 00:00:40,520 --> 00:00:44,000 Speaker 1: researchers asked what happens when we look at coffee and 12 00:00:44,040 --> 00:00:46,599 Speaker 1: tea together, because if you think about it, a lot 13 00:00:46,600 --> 00:00:49,879 Speaker 1: of people drink both. Now, this is a pretty big study. 14 00:00:50,240 --> 00:00:54,160 Speaker 1: There's about one hundred and thirty four thousand participants aged 15 00:00:54,200 --> 00:00:57,240 Speaker 1: over sixty and they were followed for a median of 16 00:00:57,320 --> 00:01:01,080 Speaker 1: thirteen half years, and during that time, more than six 17 00:01:01,600 --> 00:01:07,560 Speaker 1: four hundred of them developed neurodegenerative diseases, including Alzheimer's, Parkinson's, 18 00:01:07,680 --> 00:01:12,120 Speaker 1: vascular dementia, and als. And the findings were pretty interesting. 19 00:01:12,480 --> 00:01:16,080 Speaker 1: What they find with coffee. First of all, coffee on 20 00:01:16,160 --> 00:01:20,800 Speaker 1: its own was a jay shaped relationship between coffee consumption 21 00:01:21,040 --> 00:01:25,679 Speaker 1: and neurodegenerative disease risk. In simple terms, what that means 22 00:01:26,080 --> 00:01:29,759 Speaker 1: is that moderate coffee intake seemed to be a little 23 00:01:29,800 --> 00:01:33,680 Speaker 1: bit beneficial, but higher intake appeared to increase the risk 24 00:01:33,800 --> 00:01:38,240 Speaker 1: of neurodegenerative diseases. And in this study the risk increased 25 00:01:38,280 --> 00:01:42,600 Speaker 1: with anything from four to six cups, and specifically, more 26 00:01:42,640 --> 00:01:45,640 Speaker 1: than five cups of coffee per day was associated with 27 00:01:45,680 --> 00:01:50,600 Speaker 1: the higher risk of primary neurodegenerative diseases compared with people 28 00:01:50,600 --> 00:01:54,160 Speaker 1: who didn't drink anything. Now, that is actually pretty consistent 29 00:01:54,280 --> 00:01:59,120 Speaker 1: with previous research. In fact, earlier uko by bag studies 30 00:01:59,240 --> 00:02:02,200 Speaker 1: have shown that very very high coffee consumption six or 31 00:02:02,240 --> 00:02:06,120 Speaker 1: more per day is associated with increased dementia risks, So 32 00:02:06,200 --> 00:02:10,560 Speaker 1: this really reinforces it. Now, let's talk about TA. That 33 00:02:10,639 --> 00:02:15,880 Speaker 1: showed a completely different story. TA consumption showed protective associations 34 00:02:16,240 --> 00:02:21,320 Speaker 1: across multiple neurodegenerative diseases. People who drank any T at 35 00:02:21,360 --> 00:02:25,160 Speaker 1: all had lower risk of all cause neurodegenera of diseases, 36 00:02:25,600 --> 00:02:31,280 Speaker 1: primary neurodegeneral diseases, vascular ones, Parkinson's disease and vascular dementia. 37 00:02:32,360 --> 00:02:36,480 Speaker 1: And for example, people who drank more than three cups 38 00:02:36,919 --> 00:02:39,040 Speaker 1: of tea per day, and there was no real upper 39 00:02:39,040 --> 00:02:42,840 Speaker 1: limit here, but they had about on average about a 40 00:02:43,000 --> 00:02:47,120 Speaker 1: seventeen percent lower risk of all of those neurodegenerative diseases 41 00:02:47,160 --> 00:02:49,920 Speaker 1: compared to people who drunk nothing. Now that is a 42 00:02:49,960 --> 00:02:53,960 Speaker 1: pretty significant effect, but it showed that it didn't keep 43 00:02:54,040 --> 00:02:58,160 Speaker 1: on getting better. There kind of was a cap above 44 00:02:58,720 --> 00:03:01,600 Speaker 1: sort of three to five cups of tea. But a 45 00:03:01,639 --> 00:03:05,200 Speaker 1: really interesting finding in this was the combination of coffee 46 00:03:05,240 --> 00:03:09,080 Speaker 1: and tea together, and the researchers looked at both of them. 47 00:03:09,600 --> 00:03:15,280 Speaker 1: Certain combinations appeared to give you some protection. So people 48 00:03:15,280 --> 00:03:18,560 Speaker 1: who drank no coffee but more than three cups of 49 00:03:18,600 --> 00:03:23,640 Speaker 1: tea per day, that's me, it's my bracket. Slightly lower 50 00:03:23,720 --> 00:03:26,600 Speaker 1: risk of neurodegenitive diseases, as we said earlier, on about 51 00:03:26,600 --> 00:03:31,040 Speaker 1: seventeen percent. But people who drank moderate coffee plus moderate 52 00:03:31,360 --> 00:03:36,080 Speaker 1: or high tea intake also had to reduce risk. And 53 00:03:36,400 --> 00:03:40,760 Speaker 1: the researchers suggested that tea may partially offset some of 54 00:03:40,800 --> 00:03:45,240 Speaker 1: the risks associated with coffee, and that the two drinks 55 00:03:45,280 --> 00:03:49,680 Speaker 1: may interact with each other rather than acting independently. So 56 00:03:49,760 --> 00:03:54,160 Speaker 1: what's going on. What's the plausible mechanisms for some of 57 00:03:54,200 --> 00:03:57,320 Speaker 1: these benefits or risks. Well, the first one is about 58 00:03:57,320 --> 00:04:01,280 Speaker 1: caffeine and brain plasticity. We know that other caffeine intake 59 00:04:01,800 --> 00:04:06,320 Speaker 1: can enhance neuronal resilience in plasticity, which may help protect 60 00:04:06,640 --> 00:04:12,880 Speaker 1: against these diseases. And caffeine also influencers neurotransmitters like dopamine 61 00:04:12,880 --> 00:04:18,000 Speaker 1: and adenazine, and they're both implicated in neurodegenerative conditions. However, 62 00:04:18,040 --> 00:04:21,880 Speaker 1: when caffeine intake gets very high, the effects might flip 63 00:04:22,400 --> 00:04:26,360 Speaker 1: and it may cause increased cholesterol and triglycerides, which are 64 00:04:26,400 --> 00:04:30,600 Speaker 1: both risk factors for vascular disease and dementia. So the 65 00:04:30,600 --> 00:04:34,440 Speaker 1: second thing that's going on here is polyphenols and antioxidants. 66 00:04:34,960 --> 00:04:39,800 Speaker 1: Both coffee and tea contain large amounts of polyphenols which 67 00:04:39,800 --> 00:04:45,279 Speaker 1: have anti inflammatory and antioxidant effects and ourselves, but the 68 00:04:45,360 --> 00:04:49,919 Speaker 1: types of polyphenols differ. Coffee is rich in something called 69 00:04:50,360 --> 00:04:58,640 Speaker 1: hydrosnamic acids, and t contains catechins including EGCG. Now, these 70 00:04:58,680 --> 00:05:03,120 Speaker 1: compounds can reduce o of stress, reduce inflammation, protect your neurons, 71 00:05:03,640 --> 00:05:08,080 Speaker 1: and improve your mitrochondrial function, and importantly, they may work 72 00:05:08,120 --> 00:05:13,120 Speaker 1: through different molecular pathways, and this might explain why moderate 73 00:05:13,200 --> 00:05:17,960 Speaker 1: coffee with moderate to high TA might produce additive effects. 74 00:05:18,360 --> 00:05:22,000 Speaker 1: And then the third plausible mechanism here is amyloid beta 75 00:05:22,080 --> 00:05:26,120 Speaker 1: and Alzheimer's disease. You have heard that accumulation of amyloid 76 00:05:26,200 --> 00:05:30,120 Speaker 1: beta is associated with Alzheimer's disease. We don't know if 77 00:05:30,120 --> 00:05:33,480 Speaker 1: it's a cause yet, but we know that T polyphenols, 78 00:05:33,560 --> 00:05:40,960 Speaker 1: particularly EGCG, they appear to inhibit amyloid beta aggregation, potentially 79 00:05:41,000 --> 00:05:45,800 Speaker 1: slowing neurodegenerative processes. And animal studies also suggest that T 80 00:05:46,080 --> 00:05:51,360 Speaker 1: polyphenols can protect dopamine neurons, which may explain this association 81 00:05:51,839 --> 00:05:55,800 Speaker 1: with reduced Parkinson's risk. And then the last thing that 82 00:05:55,920 --> 00:05:59,479 Speaker 1: could be at play here is brain structure changes. Some 83 00:05:59,560 --> 00:06:04,560 Speaker 1: research suggests that high coffee consumption, very high coffee consumption 84 00:06:05,000 --> 00:06:09,000 Speaker 1: may reduce gray matter volume in the brain. Our animized 85 00:06:09,440 --> 00:06:13,200 Speaker 1: control trials showed a daily caffeine intake for one week 86 00:06:13,480 --> 00:06:18,960 Speaker 1: significantly reduced gray matter volume and impowered working memory performance 87 00:06:19,000 --> 00:06:23,599 Speaker 1: compared with placebo. Now, the effect may be temporary, but 88 00:06:23,720 --> 00:06:28,279 Speaker 1: it does highlight that caffeine is a powerful neuroactive compound, 89 00:06:28,440 --> 00:06:32,279 Speaker 1: and more isn't always better. Now, there's one other potential 90 00:06:32,320 --> 00:06:36,960 Speaker 1: mechanism that comes from another research paper that showed the 91 00:06:37,000 --> 00:06:40,960 Speaker 1: people who drank coffee primarily in the morning had a 92 00:06:41,000 --> 00:06:43,799 Speaker 1: lower mortality risk. I actually talked about this quite recently, 93 00:06:44,240 --> 00:06:47,760 Speaker 1: whereas people who drank coffee throughout the entire day did 94 00:06:47,880 --> 00:06:52,320 Speaker 1: not see the same benefit. And it appears that caffeine 95 00:06:52,440 --> 00:06:55,160 Speaker 1: later in the day and coffee tens have much more 96 00:06:55,200 --> 00:06:58,800 Speaker 1: than tea. But that can disrupt your sleep, affect your 97 00:06:58,839 --> 00:07:03,039 Speaker 1: circadian rhythms, increased night time cordisol, reduced slow way of 98 00:07:03,080 --> 00:07:05,800 Speaker 1: sleep or deep sleep, and poor sleep is one of 99 00:07:05,880 --> 00:07:11,040 Speaker 1: the strongest risk factors for generaldegenerate diseases, particularly Alzheimer's disease, 100 00:07:11,160 --> 00:07:15,440 Speaker 1: and it's the deep sleep where the brain's glymphatic system, 101 00:07:15,440 --> 00:07:19,240 Speaker 1: which clears the waste is activated and lay a day. 102 00:07:19,400 --> 00:07:24,240 Speaker 1: Caffeine particularly disrupts deep sleep, So that may be what's 103 00:07:24,280 --> 00:07:27,680 Speaker 1: going on here. So what's all the takeaways here? I 104 00:07:27,680 --> 00:07:31,360 Speaker 1: think you can get a few reasonable conclusions here. Moderate 105 00:07:31,400 --> 00:07:35,560 Speaker 1: coffee intake seems fine somewhere for around one to three 106 00:07:35,640 --> 00:07:37,800 Speaker 1: cups a day. It seems to be the sweet spot, 107 00:07:38,480 --> 00:07:41,360 Speaker 1: but when you get to five or more that's where 108 00:07:41,360 --> 00:07:44,880 Speaker 1: you get into the risk range here. But T appears 109 00:07:44,920 --> 00:07:50,960 Speaker 1: to be consistently protective across multiple neurodegenital diseases, and combining 110 00:07:51,040 --> 00:07:53,200 Speaker 1: both of them may be beneficial as long as you 111 00:07:53,280 --> 00:07:57,640 Speaker 1: keep your coffee moderate. But the key really is to 112 00:07:57,680 --> 00:08:00,640 Speaker 1: do it earlier in the day, particularly the coffee UH 113 00:08:00,920 --> 00:08:04,160 Speaker 1: and tee, particularly if it's low caffeine or if it's weak, 114 00:08:04,600 --> 00:08:08,160 Speaker 1: and that's probably fine to have liater in the day, 115 00:08:08,520 --> 00:08:11,600 Speaker 1: So hopefully that gives you a little bit of insight 116 00:08:11,760 --> 00:08:14,840 Speaker 1: in a complex area. But that is it for this week, folks, 117 00:08:14,960 --> 00:08:15,720 Speaker 1: catch you next time.