Vegan Diet or Mediterranean Diet: Which Is Healthier?

thanks again for joining us Mediterranean diets they're healthy they're in the news all the time how do they compare to other kind of diets and is there a little bit of mythology in all of this what I thought I might do is talk about Mediterranean diets and contrast them with vegan diets and other diets and I think what we're gonna see is that it's not one versus the other they overlap in big ways but let's have a look a vegan diet means that you're eating fruits and grains and legumes and vegetables and it can be interpreted in all different ways a vegan diet means grains and fruits and vegetables legumes could have nuts and seeds but it excludes animal products and that could be an Italian meal obviously that could be Mexican with beans and rice and veggie fajitas it could be interpreted through Chinese cuisine so vegan is not a cuisine obviously it's not a part of the world it just means certain things are excluded it could be Japanese now a Mediterranean diet actually means I'm driving down the coast of Tuscany and I don't really care what I eat because it's just so darn beautiful here and the notion of a Mediterranean diet as a term was coined by Ansel keys who was at the University of Minnesota and one February morning he looked out of his window thinking why am I here and he thought wouldn't it be nice to be in southern Italy and found through some really innovative research at the time that diet made a big difference in whether you lived or died from cardiovascular disease and Italy did not do the best but it was pretty good if you see on this graph Japan had the lowest degenerative heart disease death rates Italy was second so the idea of the Mediterranean diet was born to look at the diets of that region now the Mediterranean region is vast it includes all of North Africa parts of the Middle East and all across the bottom of Europe but what Keyes had in mind was really southern Italy and its neighbors to the east and to the west so Greece France and maybe parts of Spain and the diet has had all different kinds of meanings but it has been codified to mean lots of plant foods not so much processing desert is not going to be pudding it'll be fruit if you use fat it would be olive oil dairy products are low eggs are low meat is low and wine is consumed in low to moderate amounts one thing is important he when Kees was using archetypal Italian villages to design with the diet meant he was looking at a place called Nicotero in particular the fat content of their diet was 23% of calories so in other words relatively low for all those people who imagine that a Mediterranean diet means opening up a bottle of olive oil and drowning your food in it not their fat content was much less than ours is here in North America ok so the basics let's go back and just talk about what are we trying to get a diet to accomplish with regard to heart disease of course the higher your cholesterol level the higher your risk of dying of coronary disease and so what makes your cholesterol go up well saturated fat the solid fat every one percent rise in your saturated fat intake will lead to roughly a 2 percent rise in LDL and despite the egg industry trying to make cholesterol look ok dietary cholesterol does contribute to plasma cholesterol as well so which foods have them and if you look at animal products and if you contrast them with plant products you see something quite dramatic animal products have cholesterol and they have a substantial amount of saturated fat plant products have no cholesterol and are extraordinarily low in saturated fat in most cases by the way let's take a look at chinook salmon you see that up there for all the people who imagine that wild-caught Sam is somehow low in saturated fat or low in cholesterol it's much more like beef than it is like broccoli okay now what about things that we wish our foods did have like fiber or vitamin C so animal products are not plant derived they don't have fiber they don't have vitamin C but you see lots of it in plant foods lots of fiber lots of vitamin C and other antioxidants as well okay so there have been a number of clinical trials on plant-based diets and Dean Ornish did his elegant studies and although he described them yesterday I want to just go back over some of the really key points he wanted to see if we could not prevent heart disease but reverse it with a four step program of vegetarian foods half hour walk managing stress which is why no physicians were in the study avoid tobacco and after a year the experimental group had a massive drop in total cholesterol and in LDL compared to an untreated control or a usual care control group their weight loss was impressive despite the fact that there was no calorie counting and what made medical history was an geographic evidence that the arteries were opening up and you could see this in a year's time with no medication in 82 percent of patients a similar trial was done in India to see if in a very different population you could have similar results so in Northwest India in Rajasthan the Mount Abu open heart trial began patients with moderate to severe coronary atherosclerosis and they were given a vegetarian diet that was near vegan and exercises stress management was part of it as well and then they asked the people oh no use of medication challenging to do that nowadays since everyone is on vitamin L but nonetheless when they the researchers did angiography at baseline and at two years they then separated the results based on adherence to the program and the high adherers had a 91% 91% of the high adherers had regression of their lesions the low adherers only 12% and if you look at how many of them had lesions regressing more than 10 percent 15 that was 51% of them and the high adherence group and then if you looked at the average diameter percent diameter changes 18 absolute percentage points in the high adherers this is like really nice result so a Mediterranean diet has been tested for primary prevention and you heard about the printed trial but let me walk you through the weeds on what the trial was attempting to do it occurred in Spain starting in 2003 and it was a big trial and very carefully put together more than 7,000 participants and the average person was overweight the average person was 67 years old and they were split into three groups one group got a Mediterranean diet in a minute I'll tell you what that meant to them plus olive oil and the idea is the olive oils can be healthy for you and they asked them to have 50 grams of olive oil a day about four tablespoons but what they actually did was they delivered to each participant a leader of olive oil per week so they made sure that nobody was low on olive oil the next group got the Mediterranean diet but instead of olive oil they were asked to have nuts roughly an ounce a day of 30 grams and then third group was the control group okay so three groups and then what the Mediterranean diet itself was was oil nuts fruits vegetables fish legumes and there's a tomato sauce that's popular in Spain called sofrito and wine for people who drank wine and the s/m not to have sodas or baked goods or fatty spreads like margarine butter and to favor white meat over red meat but they weren't necessarily pushing me so this is what people actually ate and let me interpret this for you the yellow bars that's the group that was given the olive oil and the brown bars are the group that was given asked to eat nuts and the white are the control group so we could see the yellow bars on the far left the extra-virgin olive oil in take went way up in the group that was asked to eat extra-virgin olive oil but they reduced their risk of refined oils so it wasn't that oily of a diet they were eating the olive oil they were given and not using other oils you'll notice that their vegetable intake went up in all the group's fruit intake went up in all the group's fish went up a little bit meat went down dairy went down and lest we imagine that the Mediterranean diet is all red wine all the time alcohol did not go up okay so this is three months in let me show you the end of the study pretty much the same olive oil way up in the olive oil group nuts up in the nuts group but meat and dairy down in both and alcohol not really emphasized alright so what happened well weight loss didn't really work out so well they lost about this is the first three months of the study they lost about what a quarter of a kilogram and ninety percent of the participants are overweight and to be on a special diet to be monitored this way they only lost about a quarter of a kilogram and then when they looked at did you die this is all cause mortality and you do see a suggestion of a benefit for the olive oil group but the p-value there 0.15 it's nowhere near significance and then how about do you have you died of cardiovascular disease once again a suggestion of a benefit for the oil group but there was so much variability that the p-value was just not significant so this couldn't be differentiated from a chance result but after about five years if you did a composite of did you have a myocardial infarction or stroke or did you die from cardiovascular disease the control group four point four percent olive oil group three point eight percent the nut group three point four percent okay we're at least getting somewhere and that was it that was the headline that you got this rather modest reduction from this composite endpoint now I'm not saying it's bad or a poorly done study but some people were disappointed that they couldn't get more out of it so the researcher said well wait let's look at those participants in the Preda med trial who ate more or less like vegetarians and the food the foods they considered vegetarian foods were fruits and vegetables and nuts and cereals legumes olive oil potatoes including french fries potato chips this wasn't a question of quality it was just are you eating these foods and avoiding the animal products and they made a score called the Pro vegetarian score and what they showed was that the further you went out the more you were eating like a vegetarian they'll lower your risk of dying of anything and the p-value was 0.02 so statistically significant and then specifically cardiovascular mortality same story in other words is this clear the more people adhered to a vegetarian diet avoiding the animal products and including plant products the better they did and the results were really quite dramatic more so than the overall study results and that matched what had been seen right next door in Greece in the epic cohort which is a large group of people who have been studied when you look at who lives and who dies in any given window of time the foods that reduce the risk of dying are vegetables legumes fruits and nuts cereals and ma high monounsaturated - saturated fat ratio more olive oil less butter the foods that are associated with mortality are fish dairy meat and people who don't drink enough and people who drink too much so sort that out however you want to alright so Mediterranean diets have also been used for secondary prevention the Leone trial looked at individuals in around the old France 600 of them they had already had a myocardial infarction and the question is are you gonna have another one are you gonna die and so they split them into two groups and one group got a Mediterranean diet plus a margarine that was loaded with al alpha-linolenic acid this is the omega-3 the 18 carbon omega-3 that your body hopefully lengthens and the other group got nothing so what happened when you look at their dietary intake both groups increase their vegetables then they increase their fruit a lot and both groups are eating some fish and some meat and some high-fat dairy but after 27 months there wasn't much of any effect on weight and I didn't include baseline weight they didn't they were actually heavier during the intervention in both groups than they were at baseline and if you look at their blood pressure you don't see much advantage if you look at their lipids do you make anything out of that really not I mean their total cholesterol in the two groups about the same same with LDL however if you look at their plasma linolenic acid it went up and their EP a which is the 20 carbon omega-3 that comes from it that went up and their plasma ascorbic acid vitamin c went up too okay so their lipids aren't any better really and their blood pressures not better and their weight isn't any better but something is happening in their blood so let's look at see cardiac deaths be in the experimental group there were three deaths in the control group 16 okay cardiac deaths and non-fatal mi-8 in the experimental group 33 in the control group okay now this is looking impressive despite the fact that our typical measures weren't really improving very much so if you ask the authors why did the participants do better on this diet despite the fact they didn't lose any weight and their lipids were no better they would say we gave them a margarine that was loaded with omega-3 and that helped them it's anti thrombotic and anti-arrhythmic and with vitamin C and vitamin E you've got an antioxidant effect that's going to help them as well okay yesterday dr. Freeman talked about heart failure and the medet a hf study looked at heart failure it was an observational study 991 patients everybody had heart failure mean age 80 years old and they classified the patients these heart failure patients as either adherent to a Mediterranean pattern or not adherent to a Mediterranean pattern the question was does a Mediterranean dietary pattern help you if you have heart failure and here's what they found for whether you're gonna die of anything then non-adherent people did marginally worse than the adherent people or to put it the other way the adherent people did a little better but not statistically significant difference on the other hand if you looked at were you hospitalized again okay we're getting somewhere that was a significant reduction in the likelihood of being back in the hospital so that suggests that a Mediterranean dietary pattern ought to be helpful for heart failure so the predamond researcher said alright let's look at that we're not an observational study we're an intervention trial and we can see if it helps so again they brought the individuals in who were average age 67 years old and as a sub study they looked at the heart failure and I have to say they didn't find much of anything there was a modest suggestion of a benefit for the olive oil group but it was nowhere near statistical significance unfortunately so their conclusion was at least in their hands doing the Mediterranean diet in this way it was not really an effective treatment for heart failure that does not mean that I cannot be effective for heart failure but some would argue that we got to go a little bit further so let me shift gears a little bit and talk about tackling the risk factors first is weight loss our research team brought in 64 overweight women and asked them to change their diets either a vegan diet or a National cholesterol education programs step 2 diet that's chicken and fish and no calorie limits no exercise no food given to them they had to make their own food but the typical day's meals are things that would be familiar to you like blueberry pancakes the fat intake dropped in both groups especially the vegans carbohydrates went way up in the vegan group down in the other group however the vegan group lost substantially more body weight five point eight kilograms compared to three point eight kilograms in the other group that was significant after two years the control group regained its weight the vegans never did they were skinny or at two years than before and when you look at every study ever done on plant-based diets and body weight they show a very consistent finding the zero line is on the right all the studies show weight loss okay all right why well the first is you're eating more fiber fiber has effectively no calories so your foods are less energy dense and fat has nine calories in every gram as opposed to carbohydrate which has only four so if you're eating more carbs you're getting fewer calories and that's part of why when you emphasize these plant-based foods with the low fat intake people tend to lose weight all right cheese unfortunately a 70% fat for any worse it would be Vaseline the next thing fat in foods adds easily to body fat your body can turn bread into body fat but that's a challenge for it it would much rather use it for blood sugar or turned it into glycogen but it's really easy for cheese to go to body fat it's already fat and and I oh this is a Kevin hall study that he mentioned yesterday where Hughes used isocaloric diets low fat low carb the low fat group lost about 89 grams of fat per day which was more than the low carb group our research team under Hannah's Direction has looked at the after meal calorie burned the thermic effect of food in patients when you eat lunch or breakfast your calorie burn always increases for three four or five hours but after people have been on a low-fat vegan diet it's substantially higher about 16% higher so what we are suggesting is that a fatty diet slows metabolism let me walk you through why that is this was done at Pennington in Louisiana they brought individuals in game of 50% 50% fat diet and showed that their mitochondrial biogenesis slowed down what I mean is in your cells you've got mitochondria they burn things when you fill yourselves with grease the mitochondria don't work as well anymore here all these mitochondria are trying to function but as your diet packs fat into the cells the mitochondria work less effectively fat in cells slows down your after meal burn so on a low-fat vegan diet the fat dissipates the mitochondria recover you get a better burn so another possibility comes from the gut microbiome and this is somewhat speculative but the bacteria in your gut make endotoxins that can pass into your bloodstream and they can interfere with the cells and at Virginia Tech researchers gave a high-fat diet to volunteers and their idea was that it might the endotoxin from the bacteria in the gut would pass through the digestive tract more easily on a high-fat diet and that that in turn would disrupt cellular metabolism is that true well they used a 55% fat diet for exactly five days and what they showed is that this the amount of endotoxin in the blood went right up okay this is the bacterial poisons getting into the blood and then they looked at if I have a meal does my glucose oxidation rise as it should or does it not normally you eat you oxidize and in the left before the high-fat diet they did but after the high-fat diet they did not so that what's what we think is happening is a high-fat diet somehow causes endotoxins to be swept from the digestive tract into the bloodstream interfering with cellular metabolism theory but stand by okay just finishing up LDL drops very consistently blood pressure drops very consistently on plant-based diets and a1c drops in I'm gonna skip through this in interest of time when fat gets into the muscle cells and the liver cells it interferes with insulins ability to work and that's why if a person has diabetes you don't want to tell them to not eat rice and not eat beans you want to tell them to stop eating cheese and meat and other foods that pack fat into the cells that allows insulin sensitivity to improve okay it and diets have been compared through a study called the car to veg diet a carnival study they compared a Mediterranean diet to a vegetarian diet 118 overweight adults they had high lipids or high glucose no medication use three months diet period and they were isocaloric diets either Mediterranean or vegetarian and what they showed is that total cholesterol dropped more in the vegetarian diet than the Mediterranean which is what you'd expect and LDL dropped more as well triglycerides went up a little bit in the vegetarian group but really relatively trivially from about 110 to about 115 and HDL didn't really do much of anything in either one mike Danziger at tufts compared four different diets for their weight loss effect low-carb macronutrient balance which is a little bit like Mediterranean versus a caloric restriction or an orange type diet and showed the diets are all about the same with regard to long-term weight loss although there was a little bit of an advantage for the Ornish diet but when you put weight loss together for all of these studies whether it's the leone trial or the printer med trial Mediterranean diets really are not good for weight loss but plant-based diets are really rather consistently good so where does this leave us there is a whole range of diets out there from Western to prudent all the way out to say vegan macrobiotic or raw those are ideas of what would be in the diet but they can be interpreted through Mediterranean cuisine Asian cuisine African cuisine Latin American cuisine in other words you can be Mediterranean and vegan or a Mediterranean and an omnivore so what I take from this is that the Mediterranean pattern is a good one but we want to have it be as plant-based as possible so summary we want to shift from animal-based foods to plant-based foods Mediterranean diets are heart healthy to the extent that they emphasize plant foods but we have lots of issues that the research and doing this properly so anyway I hope this has been helpful to you and thank you very much [Applause]

Channel: Physicians Committee

Views: 536,316

Keywords: diets, health, weight loss, vegan, Mediterranean diet, nutrition

Id: Xv_ykZr_8cc

Length: 24min 43sec (1483 seconds)

Published: Thu Jan 03 2019