 Felly, y gwrth gweithio gyda ni gyd, y gallwn ni, eich bod yn ei wneud, gymryd ddim yn ei ddweud yn y llunio, a chanolodd yn gweithio'r ffodol a'i ddweud i'ch gweithio'r ffordd sy'n cael ei gweithio'r ffordd.夕b, ychydig y gallwn ni'n ddweud, yw'r ysbyt wedi'u gwybod y gallwn ni'n ddweud, mae'r ddeghau'r ffordd, yn ei ddweud, o'r bwrd, yw'r ffordd, a'r bwrs, yn fwrdd. Mae'r thymau eich ddwyaf yn ffordd yw'r llwyddiadau mewn gwirioneddau'r llawr, lle mae'r llawr yn adroddodol yn lle. Ac mae'r llawr yn ni'n rhaid i'r llwyddiadau, yn llwyddiadau'r llwyddiadau. Felly mae'n cyhoedd o gweithredu'r llwyddiadau a'r llwyddiadau yn bwyd? Mae'r llwyddiadau'r llwyddiadau i'r llwyddiadau a'r llwyddiadau a'r llwyddiadau neu'r llwyddiadau yn cael ei i gael i gyflwyddiadau. Llywodraeth gyda'r cyfnod yw'r cyfnod ffordd yn cyfnodol. Llywodraeth, mae'r cyfnod bwysig, yn ymweld 100. Felly mae'r cyfnod yn cael ei ddweud o'r llwy fwy o'r teidiau o'r cyfrwyr. Mae'n ddweud o'r cyfrwyr. Mae'n ddweud o'r cyfrwyr a'r cyfrwyr. Llywodraeth cyfnod o'r cyfrwyr, mae'r cyfrwyr yn 65. Felly, mae'r cyfrwyr yn mynd. Yn ymddangos yng Nghyrch, mae'r cyfnod o'r cyfrwyr yn 95. Yn y ddweud o'r llwy fwy o'r cyfrwyr yn y cyfrwyr, mae'n singчноch cyfrwyr. Mae ymweld gan yn hyn sy'n falthawr. OK? Bapetatoes, they're like icons of healthy eating. Are they really healthy? So why do we say that baked potatoes are healthy? Because they're high in fiber and low in fat. These carpet tiles are high in fiber and low in fat. It doesn't make it good to eat, does it? But the bulk of what you're eating there is actually quite fast-releasing carbohydrate. So if you eat a baked potato of about this size, it's a bit like spooning that much sugar into your mouth, which is actually quite disruptive. Home-meal bread, fredded wheat are down here. Then we've got pasta. It's not as bad, but it's still relatively fast-releasing. And one of the problems with these foods is this, is that it's not just that they're relatively fast-releasing. It's that when we eat them, we often eat a lot of them, OK? So if you look at, you know, pasta and kiwi fruit, they have similar glycemic indices, but they're not similarly disruptive necessarily. Anyone here ever come home quite hungry quite late at night and needed something quite quick to eat and then eaten a big bowl full or plate full of pasta? Has anyone here ever done that? So this is relatively fast-releasing. You've had it in significant quantity. It's going to be quite disruptive. Who here, however hungry you've got, have come home and polished off a big bowl full or plate full of kiwi fruits? Anyone? You at the back. There's always one. Usually female. Anyway, so most people when they eat kiwi fruits will have one, or if they're going for it two, there isn't very much food there. It can't be very disruptive, do you see? Also, kiwi fruits are reasonably nutritious. I don't think they're fantastic. For me, something more nutritious might be a piece of meat, but they're not bad. Pastry is ostensibly made from refined wheat. And what's in refined wheat other than carbohydrate? And the answer to that is nothing. It's basically a bowl of sugar, not much else. That's more fodder than food. Rice, white rice, what's in it? It's a bowl of sugar really, just so you know. Now, if we were thinking about eating carbohydrate, how about slower releasing carbohydrates that are more nutritious? Would that make sense? Probably. So what have we got? This is a bit depressing, but just so you know, beans and lentils, fruits and vegetables, other than the potato, pretty much fall into these categories. But you might be looking at this list and saying, well, I don't mind eating broccoli and chickpeas and butter beans, but if my diet is going to be based on these foods for me to have a nice, long, healthy life, I may as well be dead. And if you feel that way, I empathise with you, but I've got some good news for you. And that's because there's a whole bunch of foods that we haven't discussed in this section because they don't contain sugar and they can't disrupt blood sugar. And these are foods rich in what? Protein, that's exactly right. So foods rich in protein include things like what? Meat, fish, eggs. If you like plant foods nuts and possibly seeds. So if we're thinking about eating these foods, then we're going to have stable levels of blood sugar, less likely to be hungry, not huge peaks of insulin, causing fat deposition in our fat cells. It's fantastic. So I said I was going to present to you the one single thing you need to bear in mind to judge whether a food is healthy or not. Here it comes. What is common sense dictate would be the best diet for us as a species? Probably a diet based on the foods we've been eating the longest, right, in terms of our time on this planet. Those are the foods we've evolved to eat. They're going to be the best foods for us because we're best adapted to those foods. So how long have we been on this planet? It depends who you ask, but evolutionists roughly agree on this figure of about two and a half million years. Now for most of that time, we've been hunter-gatherers, right? Eating hunted and gathered foods, these foods. When do we start to eat grain, anyone? About 10,000 years ago, that's right. Relatively recent in evolutionary terms, but it's not just a theory because we saw generally how disruptive grains can be to our chemistry. We saw they're not fabulously nutritious either, generally speaking, okay? Now, if you go along with this theory, you might be looking at this and then say, well, how come meat is bad, okay? Because we're told not to eat much meat, particularly red meat, particularly fatty meat, eggs, heart attack on the plate, don't eat nuts, they're very fattening because they're full of fat. So something's wrong. Either the primal and evolutionary theory is true or these foods are unhealthy. You cannot have both. So let's go back to the science, okay? Away from the common sense for a moment and back to the science to look at saturated fat. Now, you've all heard of this. This is in red meat and eggs and dairy products and we're told two things. It's fattening, okay? And if we eat enough of it, we're going to get what? Heart disease, that's exactly right. Well, we've just explored this. Fat is not inherently fattening. Neither do low-fat diets work for the purposes of weight loss. But why do we think that saturated fat is a cause of heart disease? Because someone basically said that in the 1970s, okay? But let me just tell you. We have had literally dozens of studies over the last 30 or 40 years that show no relationship basically between saturated fat and heart disease. But the most important thing is this. What happens when people eat less saturated fat? And the answer is nothing. No reduced risk of heart disease, stroke, diabetes, any form of cancer. And it does not extend life by a single day. Now, there's pretty good evidence to suggest that saturated fat does not cause heart disease, all right? That's what the bulk of the evidence shows. And while that might be a bit of a surprise sometimes, think of it. In terms of primal and evolutionary nutrition, saturated fat is a constituent in red meat. Let's say we've been on this planet two and a half million years. How long have we been eating saturated fat for? And the answer is all the time. That's exactly right. And therefore, something we should be relatively well adapted to by now. Now, could you take this principle and apply it to other foods? Here's some oily fish. These are sardines, but mackerel, trout, herring, also contain what are called omega-3 fats. They appear to be good for the heart. They also appear to be good for another part of the body. Where am I thinking? The brain, that's exactly right. They appear to reduce the risk of things like depression and dementia, for example. Could we have worked it out for ourselves? Yeah, probably been eating them for a very long time. Relatively natural food, likely to be good, right? How about nuts? What have we told about nuts? Don't eat too many? They're very fatty. They must be fattening. There are over a dozen studies that have looked at the impact of nut eating on weight and none of them found that they caused weight gain. Why not? So first of all, eating nuts is like putting the right fuel on the fire. They actually stimulate the metabolism quite effectively as well. Number two, probably not going to get huge surges of insulin from nuts because there isn't a huge amount of sugar or carbohydrate in them. And finally, they satisfy people. Whether a food is fattening or not depends on how much you eat of it to a certain degree and what you go on to eat later on. And there's a couple of things that seem to be important here. One is the glycemic index, the slower the better. And also protein appears to be more satisfying and nuts are relatively rich in protein. So one thing that happens when people eat nuts very often is that they just naturally eat less of other foods because they're less hungry because they've eaten something that's satisfied their appetite. Nuts also are a supremely nutritious food and quite strongly linked with this reduced risk for example of heart disease. Could we have worked it out for ourselves? Probably. Let's try another food, margarine. So what do we hear about margarine? It's better than butter. Why? It's low in saturated fat. But saturated fat doesn't appear to cause heart disease or anything. So that's a bit of a non-starter. The fact is margarine is generally made from processed vegetable oils. So one way you can process them is to bubble-hydrate them through them at very high temperature and pressure to make oils that are now solid so you can spread them. And it also extends their shelf life. But they've only been in the diet, I don't know, a few decades, okay? So what's the likelihood that we're well adapted to these? Not high, right? Turns out that they're strongly linked with heart disease. So is margarine really better than butter? Is it? Yes or no? Well, saturated fat is a non-starter. But then we're told that margarine reduces cholesterol. Well, when people take dietary steps to reduce cholesterol it doesn't reduce the risk of heart disease. That's what the studies show. But even if it did, does the fact that something reduced cholesterol make it automatically healthy? If in this glass of water here I had a mixture of arsenic and cyanide and I've found this to be an effective cholesterol-reducing agent would it make sense for me to recommend that we all have arsenic and cyanide every day? And the answer is no. Because the important thing is not the impact that a food has on cholesterol. It's the impact that it has on what? Health. And it's not the same thing. Now, there is no evidence that I can find in the scientific literature that margarine is healthier than butter. In fact, there is some evidence that points in the opposite direction, okay? Now, can we explain this somehow? Butter is not a primal food. It just isn't, okay? You don't see early man, do you? Sitting around campfires, slathering butter onto it. You don't see bread either, but you don't see butter. But the good thing about butter is it's got two main constituents, two main fats in it. Saturated fat, which has been in the diet forever, as well as mono-unsaturated fat that's in things like nuts and seeds and avocado that's also been in the diet forever. So it's relatively primal from that perspective. Can you say that for margarine? Not really. You take a blend of vegetable oils that you partially hydrogenate, say, to make a class of fats never before known in the human diet until about, I don't know, 50 years ago. Now, you've got something that is grey and stinks. To make that edible, and I use that term very loosely indeed, you would have to, number one, bleach it chemically, then deodorise it chemically, colour it chemically, flavour it chemically, stabilise it chemically, add an emulsifying agent, stop it separating out, and then you'd extrude that into a plastic tub and sell that to us, the unsuspecting public, as something healthier than we've basically been consuming for all of our time on this planet. It doesn't really make sense. This is the chemical processing of margarine just so that you're aware. I'm just going to show you the chemical processing now of butter, and that more or less tells you everything you need to know. Now, most of you will know and will have gleaned from this that another relatively new food that we don't want to be eating too much of is sugar that's taken out of sugar beet or sugar cane or now corn, and then added into whatever, a can of cocoa or chocolate bar. Now, there's links between sugar consumption and a variety of health issues. Most people are familiar with a lot of this, but maybe not heart disease, which has been out there for quite a long time, but it hasn't really got so much attention because of our focus on fat. So, is there a healthy alternative to sugar? Well, we're told that artificial sweeteners are better because they're sweet, but they contain no calories. So, we'll look at that in a moment. Are they effective for the purpose of the weight loss? But let's choose one artificial sweetener here as spartane. Look at the chemistry of it. It's actually got three molecules in it, aspartic acid, phenylalanine, and methanol, and all of these are potentially toxic to the nervous system and actually are associated with some adverse effects on health. So, there is at least some scientific evidence linking them with problems such as depression. There's lots and lots of anecdotal evidence that suggests that these things can be damaging to health. But also, there is some evidence that's generally supplied by the industry that tells us that everything's fine and we don't need to worry about the links with headaches or depression or whatever. The fact is that whether a study is funded by the industry or not appears to have a very important bearing on the results that you get from that study. So, every single industry funded study says it's fantastic and more than 90% of independently funded work says there's cause of a concern here. We don't need to get too bogged down in this and the reason is that ultimately you need to ask yourself this question is this going to be effective for the purposes of weight loss? To know that, you'd have to conduct what are called placebo-controlled studies and there is not one of these in the scientific literature. So, why not? Well, they either haven't been done or they have been done and maybe haven't been published. I don't know the answer. What I do know is this. There is independently funded work in animals that shows when you feed them artificially sweetened foods compared to when they're eating sugar-sweetened foods they get hungrier, eat more and get fatter. Could we have worked this out for ourselves? Probably. Here's how. Is this a relatively new or an old food? New or old? It's new. It's very new. Likely that we have the biochemical metabolic machinery necessary to deal with this stuff is low. Likely that this might be actually quite problematic to health. It's actually quite high overall. So, when should we eat? So, what we told? Eat three meals a day. We looked at that earlier. That may not be the best way for you and also don't eat in between meals. Why? More calories means more weight. However, sometimes if you have your lunch at 12.30 and dinner isn't going to be till 8.30 you might want to eat something to stop yourself getting very hungry, right? This is a very important tactic that some people can use to control their diet and control their weight much more easily. It is not necessarily a good thing to sit in a restaurant or on a plane or in your home starving hungry. So, if you are going to snack on something, okay, save between your lunch and your evening meal to keep you from running into problems what might it be? What food specifically? What snack food? Nuts. That's exactly right. And probably not fruit. The reason being mainly for many people fruit does not effectively shake the appetite.