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  • Why don't we give a big, warm welcome to Dr. Michael Greger!

  • [Applause]

  • Surely, if there was some safe, simple, side-effect-free solution

  • to the obesity epidemic, we would know about it by now, right?

  • I'm not so sure.

  • It may take up to 17 years before research findings make it

  • into day-to-day clinical practice.

  • To take one example that was particularly

  • poignant for my family: heart disease.

  • You know, decades ago, Dr. Dean Ornish and colleagues published evidence

  • in one of the most prestigious medical journals in the world

  • that our leading cause of death could be reversed with diet

  • and lifestyle changes aloneyet, hardly anything changed.

  • Even now, hundreds of thousands of Americans continue to needlessly die

  • from what we learned decades ago was a reversible disease.

  • In fact, I had seen it with my own eyes.

  • My grandmother was cured of her end-stage heart disease

  • by one of Dean's predecessors, Nathan Pritikin, using similar methods.

  • So, if effectively the cure to our number-one killer of men and women

  • could get lost down some rabbit hole and ignored,

  • what else might there be in the medical literature

  • that could help my patients, but that just didn't have

  • a corporate budget driving its promotion?

  • Well, I made it my life's mission to find out.

  • That's why I became a doctor in the first place and why I started

  • my nonprofit site, NutritionFacts.org.

  • Everything on the website is free.

  • There are no ads, no corporate sponsorship.

  • It's strictly noncommercial, not selling anything.

  • I just put it up as a public service, as a labor of love,

  • as a tribute to my grandmother.

  • [Applause]

  • New videos and articles nearly every day

  • on the latest in evidence- based nutritionwhat a concept.

  • Ok, so, what does the science show is the best way to lose weight?

  • If you want testimonials and before-and-after pictures,

  • you have come to the wrong place.

  • I'm not interested in anecdotes; I'm interested in the evidence.

  • When it comes to making decisions as life-and-death-important

  • as the health and well-being of yourself and your family,

  • there's really only one question:

  • What does the best available balance of evidence show right now?

  • The problem is that even just sticking to the peer-reviewed medical literature

  • is not enough as, “False and scientifically [misleading] unsupported beliefs

  • about obesity are pervasiveeven in scientific journals.

  • The only way to get at the truth, then, is to dive deep

  • into the primary literature and read all

  • the original studies themselves.

  • But, who's got time for that?

  • There are more than half a million scientific papers

  • on obesity with a hundred new ones published every day.

  • Even researchers in the field might not be able to keep track

  • beyond their narrow domain.

  • But that's what we do at NutritionFacts.org.

  • We comb through tens of thousands of studies a year so you

  • don't have to.

  • Very nice!

  • And indeed, we uncovered a treasure trove of buried data,

  • like today I'll cover simple spices, for example, proven in

  • randomized, double-blind, placebo- controlled trials to accelerate weight loss

  • for pennies a day, but with so little profit potential,

  • it's no wonder these studies never saw the light of day.

  • The only profiting I care about, though, is your health.

  • That's why 100% of all the proceeds I receive from all of my books,

  • and DVDs, and speaking engagements are all donated to charity.

  • I just want to do for your family what Pritikin did for my family.

  • But wait, isn't weight loss just about eating less and moving more?

  • I mean, isn't a calorie a calorie?

  • That's what the food industry wants you to think.

  • The notion that a calorie from one source is just as fattening

  • as any other is a trope broadcast by the food industry

  • as a way to absolve itself of culpability.

  • Coca-Cola itself even put an ad out there emphasizing

  • thisone simple common-sense fact.”

  • As the current and past chairs of the Harvard's nutrition department put it,

  • thiscentral argumentfrom industry is that theoverconsumption of calories

  • from carrots would be no different than the overconsumption of calories from soda

  • If a calorie is just a calorie, why does it matter what we put in our mouths?

  • Let's explore that example of carrots versus Coca-Cola.

  • It's true that in a tightly controlled laboratory setting,

  • 240 calories of carrots (10 carrots) would have the same effect

  • on calorie balance than the 240 calories in a bottle of Coke,

  • but this comparison falls flat on its face out in the real world.

  • You could chug those liquid candy calories in less than a minute,

  • but eating 240 calories of carrots would take you more than

  • two-and-a-half hours of sustained constant chewing.

  • Not only would your jaw get sore, but 240 calories of carrots

  • is like five cupsyou might not even be able to fit them all in.

  • Our stomach is only so big.

  • Once we fill it up, stretch receptors

  • in our stomach wall tell us when we've had enough,

  • but different foods have different amounts of calories per stomachful.

  • Some foods have more calories per cup, per pound, per mouthful than others.

  • This is the concept of calorie density:

  • the number of calories in a given amount of food.

  • Three pounds is about what the average American eats in a day.

  • As you can see, for example, oil, is a high calorie density,

  • meaning a high calorie concentration, lots of calories packed into a small space, so

  • drizzling just a tablespoon of oil onto a dish adds over a hundred calories.

  • For those same calories, you could have instead eaten about

  • two cups of blackberries, for example, a food with a low calorie density.

  • So, these two meals have the same number of calories.

  • You could swig down that spoonful of oil

  • and not even feel anything in your stomach,

  • but eating a couple of cups of berries could start to fill you up.

  • That's why yes, biochemically a calorie is a calorie,

  • but eating the same amount of calories in different foods,

  • can have different effects.

  • The average human stomach can expand to fit about four cups of food;

  • so, a single stomachful of strawberry ice cream, for example,

  • could max out our caloric intake for the entire day.

  • For the same 2,000 calories, to get those same 2,000 calories

  • from strawberries themselves

  • you'd have to eat 44 cups of berries.

  • That's 11 stomachfuls.

  • As delicious as berries are, I don't know if I could fill my stomach

  • to bursting 11 times a day.

  • Some foods are just impossible to overeat.

  • They're so low in calorie density, you just physically

  • couldn't eat enough to even maintain your weight.

  • In a lab, a calorie is a calorie, but in life, far from it.

  • Traditional weight-loss diets focus on decreasing portion size,

  • but we know theseeat lessapproaches can leave people

  • feeling hungry and unsatisfied.

  • A more effective approach may be to shift the emphasis from restriction

  • to positiveeat moremessaging of increasing intake of healthy,

  • low-calorie-density foods, but you don't know, until you

  • put it to the test.

  • Researchers in Hawaii tried putting people on more of a traditional,

  • Hawaiian diet with all the plant foods they could eat,

  • unlimited quantities of fruits, vegetables, whole grains, beans.

  • And, the study subjects lost an average of 17 pounds in just 21 days.

  • Calorie intake dropped by 40%, but not because they were eating less food.

  • They lost 17 pounds in three weeks eating more food,

  • in excess of four pounds a day.

  • How could that be?

  • Because whole plant foods tend to be so calorically dilute,

  • you can stuff yourself without getting the same kind of weight gain.

  • They lost 17 pounds in three weeks eating more food.

  • That's why in my upcoming new book, How Not to Diet,

  • which I am very excited about, [clears throat],

  • that's whyLow in Calorie Densityis on my list of the 17 ingredients

  • for an ideal weight loss diet.

  • As noted before, Americans appear to average about three pounds of food a day.

  • So, if you stuck with mostly these foods, you can see how you can eat more food

  • and still shed pounds.

  • A landmark study set to be published next month, found that

  • even when presented with the same number of calories,

  • and the same salt, sugar, fat, fiber and protein,

  • processed foods led to weight gain, two pounds gained over two weeks;

  • and unprocessed foods led to weight loss, two pounds down in the same two weeks.

  • Here's one of their processed food meals

  • which is probably healthier, actually, than what most people eat.

  • Non-fat Greek yogurt, baked potato chips, sugar-free diet lemonade

  • with a turkey sandwich, has the same number of calories as this

  • what the unprocessed-meal-food folks were eating,

  • a kind of a southwest entrée salad with black beans, avocados, nuts

  • that's the calorie density effect.

  • Same calories but there's just more food,

  • no wonder it satisfied their hunger.

  • And they ended up four pounds lighter in two weeks eating more food.

  • So, how can you decrease the calorie density of your diet?

  • Well, just a quick peek at the two extremes should suggest two methods:

  • abandon added fats and add abandoned vegetables.

  • Method number one: Covertly put people on a relatively low-fat diet,

  • and they tend to lose body fat every day even though

  • they can eat as much as they want.

  • But if you instead give those same people the same meals,

  • but this time sneak in enough extra fats and oils

  • to change it to a high-fat diet, they gain body fat every day.

  • In fact, in a famous prison experiment in Vermont,